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Sample records for ferrous process metallurgy

  1. Improving the effectiveness of heat use in ferrous metallurgy

    Energy Technology Data Exchange (ETDEWEB)

    Yegorichev, A P; Lisiyenko, V G; Rozin, S Ye; Shchelokov, Ya M

    1980-01-01

    Ferrous metallurgy of the USSR consumes about 10% of the total consumption of fuel in the country. The specific consumption of fuel in 100-150-T open-hearth furnaces in the scrap-process flucuate (in kilograms of conventional fuel/T of metal) from 199-206 to 244-249, in 450-T open-hearth furnaces with scrap-ore process from 108 to 135, in method furnaces with step-like beams from 70 to 123, in heating furnaces of low-grade machines ''250'' through 55.4 to 79, and on heating pits of bloomings from 32.5 to 55.3. In openhearth production, the percentage of outlays for fuel is 2.5-4.5%, in rolling 0.6-2% of the net cost of conversion. The overconsumption of fuel up to 5% will increase the net cost of conversion by 0.030.23%. In order to increase the effectiveness of conservation of fuel in ferrous metallurgy, a new method has been proposed for evaluating the energy intensity of the final product of ferrous metallurgy which makes it possible to determine comprehensive energy outlays for the manufactured product. A new system has been developed for stimulating the enterprises of ferrous metallurgy in the struggle for conservation and reduction in the specific consumption norms of fuel. It is based on the establishment of average-sector and progressive standards for single-type units of equal output.

  2. Metallurgy - steel and non-ferrous metals

    International Nuclear Information System (INIS)

    Wusatowski, R.

    1999-01-01

    Several actual problems of metallurgy and processing of the chief metals and their alloys, especially of steel, copper, zinc and aluminium were discussed. The thought was given to the problems of: scientific, technical (also the energy consumption of production, the evolution of technology), organizational, economical, even political nature (influence of the state on the development of industry). (author)

  3. [Factors of working environment and process on non-ferrous metallurgy enterprises in Bashkortostan Republic and workers' occupational health].

    Science.gov (United States)

    Bakirov, A B; Takaev, R M; Kondrova, N S; Shaĭkhlislamova, E R

    2011-01-01

    The authors studied factors of working environment and process on nonferrous metallurgy enterprises in Bashkortostan Republic and evaluated their influence on the workers' occupational health over 1997-2009, with consideration of occupation, sex, age, length of service, work conditions and characters. The article demonstrates that sanitary and hygienic characteristics of occupations connected with machinery operation are prone to increased integral evaluation of work conditions due to underestimation of actual hardiness and intensity of work.

  4. The economic analysis of the evolution of Romanian ferrous metallurgy

    Directory of Open Access Journals (Sweden)

    I. Bostan

    2012-10-01

    Full Text Available The ferrous metallurgy represents a traditional occupation, being extremely important for the national economy. Romania has gone through all the stages foreseen for the restructuring of this industry in compliance with the provisions of the European Council’s Decision (1999/582/EC concerning the partnership for the EU adherence, which included a special chapter on ferrous metallurgy, the provisions of the Protocol no. 2 (ECSC, as well as with other significant normative acts subsequently enacted. Following the performed restructuring – privatizations, state allowances, liquidations, re-technologization – the activity of this sector has developed, still being under the potential of the Romanian metallurgic industry. Nowadays, the disadvantages relating to energy intensity and the increased need for imported raw materials are doubled by the difficulties generated by the global crisis.

  5. Ferrous Metal Processing Plants

    Data.gov (United States)

    Department of Homeland Security — This map layer includes ferrous metal processing plants in the United States. The data represent commodities covered by the Minerals Information Team (MIT) of the...

  6. CURRENT STATE AND TENDENCIES OF DEVELOPMENT OF FERROUS METALLURGY IN THE EAEU COUNTRIES

    Directory of Open Access Journals (Sweden)

    N. P. Dragun

    2016-01-01

    Full Text Available The analysis of modern status and tendencies of development of ferrous metallurgy in the countries of the EAEU is described in the article. On the basis of the conducted analysis are revealed the identified systemic problems of metallurgy and the conclusions on possible ways of their solution using the potential of integration are given.

  7. Development of structural diagram of automated dispatch control system for power consumption at non-ferrous metallurgy enterprises

    Science.gov (United States)

    Klyuev, R. V.; Bosikov, I. I.; Madaeva, M. Z.; A-V Turluev, R.

    2018-03-01

    The structural scheme of the automated control system of power consumption at the industrial enterprise is developed in the article. At the non-ferrous metallurgy enterprise, an energy inspection and a rank analysis of the electrical energy consumption of the main processing equipment were carried out. It is established that the enterprises of non-ferrous metallurgy are a complex process system consisting of a set of thousands of jointly functioning technological facilities. For the most effective estimation of power consumption of enterprises, it is reasonable to use the automated system of dispatching control of power consumption (ASDCPC). The paper presents the results of the development of the ASDCPC structural diagram that allows one to perform on-line control and management of the energy and process parameters of the main production units and the enterprise as a whole. As a result of the introduction of ASDCPC at the non-ferrous metallurgy enterprise, the consumed active power was reduced during the peak hours of the load by 20%, the specific electricity consumption - by 14%, the cost of the energy component in the cost of production of hard alloys - by 3%.

  8. State-of-the-art and main options to improve fuel-energy complex of ferrous metallurgy

    Energy Technology Data Exchange (ETDEWEB)

    Rozenblit, G I; Pashkov, V D; Romanov, G M

    1981-01-01

    In 1980, the State Institute for the Design and Planning Metallury (Gripromez), elaborated ''The main options of Fuel and energy resources conservation (FERG) in ferrous metallurgy of the USSR program of works for the period 1981-1985 and up to 1990''. The Gipromez technical committee recommended: 1) elaborating feasibility studies and reports, developing branch schemes and starting complexes to separate out FERC measures; 2) inclusion of the FERC measures at the starting complexes as the first stages of main projects construction; 3) that the Ministy of Ferrous Metallurgy of the USSR, general designers and enterprises reconsider the starting complexes of the projects constructed during the present five-year period and incorporate in them the urgent FERC actions on heat-utilizing facilities. Changing the steel smelting process structure through more extensive use of the converter process and installation of continuous blank casting allows achievement of considerable fuel conservation, some 4 m trf per year as compared with its consumption in the scheme of open-hearth furnace - blooming mill (slabbing mill). During the 11th five-year-plan period introduction of metallurgy plant. An installation with discharge of the converter gas without its afterburning and successive utilization as a fuel in the converter shop of the Novolipetsk is planned.

  9. [The organization of the comprehensive prevention of urolithiasis among ferrous metallurgy workers].

    Science.gov (United States)

    Egorova, A M

    2009-01-01

    The purpose of study is to evaluate the effectiveness of the set of preventive measures as applied to 321 workers of basic ferrous metallurgy specialties (steel makers, mill men, hot metal shearers). During the clinical examination all the workers were divided on three groups: the workers without any pathology (11.83%, the first group), the workers with metabolic disorders only without urolitiasis (64.81%, the second group) and the workers with urolitiasis diagnosis approved by ultrasonography (23.36%, the third group). The effectiveness of rehabilitation measures was evaluated during half a year (diet therapy, drinking regimen, medicinal plants treatment). After the course of preventive measures was applied the overall health condition of most workers ameliorated and the number of workers with urolitiasis development risk factors reliably decreased up to 6-12%.

  10. Aluminum powder metallurgy processing

    Energy Technology Data Exchange (ETDEWEB)

    Flumerfelt, J.F.

    1999-02-12

    The objective of this dissertation is to explore the hypothesis that there is a strong linkage between gas atomization processing conditions, as-atomized aluminum powder characteristics, and the consolidation methodology required to make components from aluminum powder. The hypothesis was tested with pure aluminum powders produced by commercial air atomization, commercial inert gas atomization, and gas atomization reaction synthesis (GARS). A comparison of the GARS aluminum powders with the commercial aluminum powders showed the former to exhibit superior powder characteristics. The powders were compared in terms of size and shape, bulk chemistry, surface oxide chemistry and structure, and oxide film thickness. Minimum explosive concentration measurements assessed the dependence of explosibility hazard on surface area, oxide film thickness, and gas atomization processing conditions. The GARS aluminum powders were exposed to different relative humidity levels, demonstrating the effect of atmospheric conditions on post-atomization processing conditions. The GARS aluminum powders were exposed to different relative humidity levels, demonstrating the effect of atmospheric conditions on post-atomization oxidation of aluminum powder. An Al-Ti-Y GARS alloy exposed in ambient air at different temperatures revealed the effect of reactive alloy elements on post-atomization powder oxidation. The pure aluminum powders were consolidated by two different routes, a conventional consolidation process for fabricating aerospace components with aluminum powder and a proposed alternative. The consolidation procedures were compared by evaluating the consolidated microstructures and the corresponding mechanical properties. A low temperature solid state sintering experiment demonstrated that tap densified GARS aluminum powders can form sintering necks between contacting powder particles, unlike the total resistance to sintering of commercial air atomization aluminum powder.

  11. Powder metallurgy ferrous synchronizer ring with brass-based friction layer; Tetsu-do niso shoketsu synchronize ring no kaihatsu

    Energy Technology Data Exchange (ETDEWEB)

    Okajima, H; Yoshikawa, K; Miyajima, K; Sugiyama, M [Toyota Motor Corp., Aichi (Japan); Nakamura, M; Ito, M [Japan Powder Metallurgy Co. Ltd., Tokyo (Japan)

    1997-10-01

    Synchronizer rings for manual transmissions are generally made of brass or molybdenum coated brass. Powder metallurgy (PM) synchronizer ring was developed for the purpose of high performance and cost reduction. This synchronizer ring consists of the high strength PM ferrous ring that needs neither special densification nor heat treatment, and it has the brass-based friction layer. New joining technique was required because of that shape and two different materials. Powder of copper-phosphorus alloy are admixed with the friction material. While sintering, that melt and migrate to the interface. Then the friction layer and the ferrous ring are joined tightly. 7 refs., 9 figs., 6 tabs.

  12. Problem concerning the use of secondary fuel energy systems in ferrous metallurgy

    Energy Technology Data Exchange (ETDEWEB)

    Shchelokov, Ia M

    1981-01-01

    Ferrous metallurgy makes available significant amount of secondary fuel energy resources: the possible output of secondary energy resources amounts to about 400 to 450 million gigajoules, the capacity of using secondary energy resources amount to 140 to 150 million gigajoules. Eighty percent of the general amount of the used secondary fuel energy resources is used in mills of open-hearth, rolling, and aneealing production. In the last twenty-five years and in connection with the change in the technological plans in the metallurgical industry, the specific output of secondary energy resources by branch decreased from 4.5 to 2.25 gigajoules per one ton of steel. The designs of mass produced boiler users does not correspond to the technical needs of the developing technology of smelting and annealing production. The Uralenergochermet together with the Ural branch of the F. Dzerzhinski All-Union Heat Engineering Institute, in 1970, introduced into use at the Orsko-Knalilov metallurgical plant, an impulse purification boiler user system. Note is made of the positive test of the operation of the Seversk pipe plant in respect to the dispersion and burning of the grease and fuel oil by products hydrated up to 30 to 40% by using the heat in the boiler users. In a number of Ural metallurgy plants, a 100% use of secondary energy resources in the course of the year was insured. Excellent results were obtained concerning the insurance of the stable operation of the system of the used thermal energy center at the Magnezit Satkin plant.

  13. Scientific Council of the State Committee for Science and Technology on the problem 'New processes in the coking industry', Coke-Chemistry Section of the Scientific-Technical Council of the Ministry of Ferrous Metallurgy of the USSR and of the Central Administration of the Scientific-Technical Branch of Ferrous Metallurgy

    Energy Technology Data Exchange (ETDEWEB)

    Bukvareva, O.F.

    1986-12-01

    A report is presented on 3 conferences on the development of the Soviet coking industry held in February and April 1986. Papers delivered at the conferences and selected recommendations for development of equipment for coking, coking systems, optimization of coal mixtures for coking, environmental protection and research programs on coking are reviewed. The following problems were discussed: modernization of coke oven design, selecting the optimum size of coke ovens, prospects for dry coke quenching in the USSR, evaluation of operation of systems for dry coke quenching, utilization of waste heat from coke quenching for heat treatment of coal mixtures for coking, research programs on coking in the 12th five-year plan (1986-1990), partial briquetting of coal mixtures for coking and selecting optimum binders for partial briqetting, formed coke processes, economic analysis of formed coke processes, fire-resistant bricks and elements for coke oven construction, new coking technologies, pollution control in coking plants.

  14. From the Scientific Council of the State Science and Technology Committee on New processes in the coking and chemical industry, Coking and Chemical Products Divisions of the Science and Technological Council of the Ministry of Ferrous Metallurgy of the USSR and Central Plenum of Scientific and Technological Associations of the Ferrous Metallurgy Industry

    Energy Technology Data Exchange (ETDEWEB)

    Ermolova, V.P.

    1985-06-01

    Joint conference took place on 5-7 December 1984 in Moscow. Reports were presented on the following topics: status of implementing the union-wide scientific and technological programs on coking by-products and organizing the production of coke briquet fuel in 1984; developments in the coking and chemical industry up to the year 2000; developing a raw material base for coking up to the year 2000; state of research on thermal processing with hot coke; training engineers for the coking and chemical industry; on planning the work of the scientific council in 1985.

  15. Estimation of snow pollution in the region of non-ferrous metallurgy enterprises by the neutron activation method

    International Nuclear Information System (INIS)

    Khatamov, Sh.; Khamidova, R.; Kist, A.A.

    1980-01-01

    Possibility of determination of more than 25 chemical elements in snow water selected in the region of non-ferrous metallurgy enterprises has been shown using the methods of neutron activation and γ-spectrometry of high resolution. Elements were determined from one sample by three-fold irradiation in the nuclear reactor depending on the half-life period and other nuclear activation parameters of the formed radioisotopes. The analysis of snow cover has revealed the character of pollution of surrounding medium and air basin by toxical elements

  16. Ferrous alloy metallurgy, liquid lithium corrosion and welding. Final report, April 1, 1973-March 31, 1984

    International Nuclear Information System (INIS)

    Olson, D.L.; Matlock, D.K.

    1984-01-01

    This research program consists of two parts: an evaluation of the corrosion behavior of ferrous alloys in liquid lithium, and a study of microstructure development and properties of dissimilar metal weldments. A ten-year overview of the research accomplishments made is presented. The effects of liquid lithium on both uniform corrosion and grain boundary penetration in ferrous alloys has been investigated as a function of time, temperature, base metal alloy content, and liquid lithium nitrogen content. Kinetic equations for the various corrosion processes have been developed and analyzed with respect to models for corrosion and corrosion product development. The effects of liquid lithium on mechanical properties, particularly fatigue, have been studied. Results have shown that in both austenitic stainless steels and ferritic steels, liquid lithium significantly reduces the mechanical integrity of all materials by inducing liquid metal embrittlement. A model for liquid metal embrittlement induced damage during fatigue was developed and shown to correlate with the experimental results. Microstructural development in austenitic weld metal, with particular emphasis on new grades with reduced chromium contents, has been investigated. The microstructures have been correlated with alloy content and the basics of a thermodynamic model for predicting weld metal microstructure has been developed. The high temperature mechanical behavior of dissimilar metal weldments (austenitic stainless steel to ferritic steel) has been investigated with the impression-creep test technique. Observed microstructural changes with position across the weldment are shown to correlate directly with creep behavior. A model based on deformation of composite materials was developed

  17. Metallurgical aspects of welding. Ferrous and nonferrous materials. 4. new rev. ed.; Die Metallurgie des Schweissens. Eisenwerkstoffe - nichteisenmetallische Werkstoffe

    Energy Technology Data Exchange (ETDEWEB)

    Schulze, Guenter

    2010-07-01

    This is the fourth edition of the standard work on welding metallurgy. The various problems of ferrous and nonferrous materials in the welding process are presented in great detail. In order to prevent corrosion of welded constructions, metallurgical properties and problems of all important technical materials are discussed, i.e. alloyed and unalloyed steels, cast iron materials, and the most relevant nonferrous materials. At the end of each chapter, the interested reader will find exercises for self-studies. Some of these can be solved using the material presented in the book while others are intended for deepening and further training. Easy examples (with solutions) are found all over the book; they are helpful because they provide information on underlying mechanisms and interdependences that are not obvious at first glance. The information was adapted to new EURO standards and international standards (up to March 2009) as far as these are relevant to Germany. New information is provided, e.g., on new steel standards (constructional steels according to DIN EN 10025), heat-treatable steels according to DIN EN 10025-6 and DIN EN 10083, high-alloy steels according to DIN EN 10088, and filler materials for steel welding according to DIN EN ISO 2560. The systematics of the ''law of cohabitation'' was applied to welding engineering for the first time here. (orig.) [German] Das in vierter Auflage erscheinende Buch widmet sich der Schweissmetallurgie mit ihren Besonderheiten. Die vielfaeltigen Probleme der Eisenwerkstoffe und der nichteisenmetallischen Werkstoffe bei ihrer schweisstechnischen Verarbeitung werden ausfuehrlich dargestellt. Um Korrosionsschaeden an geschweissten Konstruktionen vorzubeugen, wird die Metallurgie aller technisch bedeutsamen Werkstoffe, wie unlegierte und legierte Staehle, Eisen-Gusswerkstoffe, die wichtigsten NE-Metalle, ausfuehrlich besprochen. An den Kapitelenden findet der interessierte Leser Aufgaben, von denen ein

  18. Powder-Metallurgy Process And Product

    Science.gov (United States)

    Paris, Henry G.

    1988-01-01

    Rapid-solidification processing yields alloys with improved properties. Study undertaken to extend favorable property combinations of I/M 2XXX alloys through recently developed technique of rapid-solidification processing using powder metallurgy(P/M). Rapid-solidification processing involves impingement of molten metal stream onto rapidly-spinning chill block or through gas medium using gas atomization technique.

  19. Tannins in Mineral Processing and Extractive Metallurgy

    Directory of Open Access Journals (Sweden)

    Jordan Rutledge

    2015-08-01

    Full Text Available This study provides an up to date review of tannins, specifically quebracho, in mineral processing and metallurgical processes. Quebracho is a highly useful reagent in many flotation applications, acting as both a depressant and a dispersant. Three different types of quebracho are mentioned in this study; quebracho “S” or Tupasol ATO, quebracho “O” or Tupafin ATO, and quebracho “A” or Silvafloc. It should be noted that literature often refers simply to “quebracho” without distinguishing a specific type. Quebracho is most commonly used in industry as a method to separate fluorite from calcite, which is traditionally quite challenging as both minerals share a common ion—calcium. Other applications for quebracho in flotation with calcite minerals as the main gangue source include barite and scheelite. In sulfide systems, quebracho is a key reagent in differential flotation of copper, lead, zinc circuits. The use of quebracho in the precipitation of germanium from zinc ores and for the recovery of ultrafine gold is also detailed in this work. This analysis explores the wide range of uses and methodology of quebracho in the extractive metallurgy field and expands on previous research by Iskra and Kitchener at Imperial College entitled, “Quebracho in Mineral Processing”.

  20. CO2 Problems and waste recycling. Research at the Institute of ferrous metallurgy

    OpenAIRE

    Gudenau, H. W.; Senk, D.; Babich, A.; Fröhling, C.; Kueon, O. S.; Wang, S.; Wieting, X.

    2005-01-01

    In a short introduction tests and calculations about CO2-ice-blocs in the deep sea, use of CO2 for underground-coal-gasification and tertiary processes to increase oil-production by C02-flooding are shown. New activities are presented e.g. CO2-injection into EAF combined with injection of coal, coke or directreduction-fines. After research of injection of coals, fine ores or dust into blast furnaces and other shaft furnaces ...

  1. CO2 Problems and waste recycling. Research at the Institute of ferrous metallurgy

    International Nuclear Information System (INIS)

    Gudenau, H. W.; Senk, D.; Babich, A.; Frohling, C.; Kweon, O. S.; Wang, S.; Wieting, T.

    2005-01-01

    In a short introduction tests and calculations about CO 2 -ice-blocs in the deep sea,use of CO 2 for underground-coal-gasifications and tertiary processes to increase oil-production by CO 2 -flooding are shown. New activities are presented e. g. CO 2 -injection into EAF combined with injection of coal, coke or direct reduction-fines. After research of injection of coals, fine ores or dust into blast furnaces and other shaft furnaces activities are compared with injection of hot reducing gas generated by coal or waste gasification or top gas recycling combined with injection of fine solid fuels. Results of injection of prepared plastics (Duales System Deutschland), shredder-light-fraction from car-recycling and unburned carbon of power-station-ashes are discussed. Beside production of direct-reduced-iron by H 2 fluidized reactor results of the reduction behaviour ore/coal or dust/coal pellets or briquettes for the use in rotary hearth or modern shaft furnaces are shown. (Author) 76 refs

  2. CO2 Problems and waste recycling. Research at the Institute of ferrous metallurgy

    Directory of Open Access Journals (Sweden)

    Gudenau, H. W.

    2005-04-01

    Full Text Available In a short introduction tests and calculations about CO2-ice-blocs in the deep sea, use of CO2 for underground-coal-gasification and tertiary processes to increase oil-production by C02-flooding are shown. New activities are presented e.g. CO2-injection into EAF combined with injection of coal, coke or directreduction-fines. After research of injection of coals, fine ores or dust into blast furnaces and other shaft furnaces activities are compared with injection of hot reducing gas generated by coal or waste gasification or top gas recycling combined with injection of fine solid fuels. Results of injection of prepared plastics (Duales System Deutschland, shredder-light-fraction from car-recycling and unburned carbon of power-station-ashes are discussed. Beside production of direct-reducediron by H2 fluidized reactor results of the reduction behavior ore/coal or dust/coal pellets or briquettes for the use in rotary hearth or modem shaft furnaces are shown

    En una breve introducción se describen las pruebas y cálculos referentes a bloques de hielo de CO2 en el mar profundo, el uso del CO2 para la gasificación de carbón subterráneo y procesos terciarios para aumentar la producción de aceite por medio del torrente de CO2. Dentro de las nuevas actividades se presentan, por ejemplo, la inyección de CO2 en el homo eléctrico de arco (HEA combinado con la inyección de carbón, coque o de finos de los procesos de reducción directa. Después de la investigación de la inyección de carbones, se comparan, por un lado, la inyección de los minerales finos o polvos en los hornos altos y otras actividades en los hornos de cuba con la inyección del gas reductor caliente generado por la gasificación del carbón o de los residuos o reciclado del gas del tragante combinado con la inyección de finos de combustibles sólidos. En el presente trabajo se discuten

  3. Introduction to powder metallurgy processes for titanium manufacturing

    International Nuclear Information System (INIS)

    Esteban, P. G.; Bolzoni, L.; Ruiz-Navas, E. M.; Gordo, E.

    2011-01-01

    The development of new extraction processes to produce titanium in powder form leads Powder Metallurgy to an advantage position among the manufacturing processes for titanium. The cost reduction of base material, coupled with the economy of the powder metallurgy processes, give titanium industry the chance to diversify its products, which could lead to production volumes able to stabilise the price of the metal. This work reviews some of the Powder Metallurgy techniques for the manufacturing of titanium parts, and describes the two typical approaches for titanium manufacturing: Blending Elemental and Prealloyed Powders. Among others, conventional pressing and sintering are described, which are compared with cold and hot isostatic pressing techniques. Real and potential applications are described. (Author) 71 refs.

  4. Uranium 2000 : International symposium on the process metallurgy of uranium

    International Nuclear Information System (INIS)

    Ozberk, E.; Oliver, A.J.

    2000-01-01

    The International Symposium on the Process Metallurgy of Uranium has been organized as the thirtieth annual meeting of the Hydrometallurgy Section of the Metallurgical Society of the Canadian Institute of Mining, Metallurgy and Petroleum (CIM). This meeting is jointly organized with the Canadian Mineral Processors Division of CIM. The proceedings are a collection of papers from fifteen countries covering the latest research, development, industrial practices and regulatory issues in uranium processing, providing a concise description of the state of this industry. Topics include: uranium industry overview; current milling operations; in-situ uranium mines and processing plants; uranium recovery and further processing; uranium leaching; uranium operations effluent water treatment; tailings disposal, water treatment and decommissioning; mine decommissioning; and international regulations and decommissioning. (author)

  5. Modelling of injection processes in ladle metallurgy

    NARCIS (Netherlands)

    Visser, H.

    2016-01-01

    Ladle metallurgical processes constitute a portion of the total production chain of steel from iron ore. With these batch processes, the hot metal or steel transfer ladle is being used as a reactor vessel and a reagent is often injected in order to bring the composition of the hot metal or steel to

  6. Interactive data-processing system for metallurgy

    Science.gov (United States)

    Rathz, T. J.

    1978-01-01

    Equipment indicates that system can rapidly and accurately process metallurgical and materials-processing data for wide range of applications. Advantages include increase in contract between areas on image, ability to analyze images via operator-written programs, and space available for storing images.

  7. Powder Metallurgy Reconditioning of Food and Processing Equipment Components

    Science.gov (United States)

    Nafikov, M. Z.; Aipov, R. S.; Konnov, A. Yu.

    2017-12-01

    A powder metallurgy method is developed to recondition the worn surfaces of food and processing equipment components. A combined additive is composed to minimize the powder losses in sintering. A technique is constructed to determine the powder consumption as a function of the required metallic coating thickness. A rapid method is developed to determine the porosity of the coating. The proposed technology is used to fabricate a wear-resistant defectless metallic coating with favorable residual stresses, and the adhesive strength of this coating is equal to the strength of the base metal.

  8. Mechanical Properties of Lightweight Porous Magnesium Processed Through Powder Metallurgy

    Science.gov (United States)

    Zou, Ning; Li, Qizhen

    2018-02-01

    Porous magnesium (Mg) samples with various overall porosities (28.4 ± 1.8%, 35.5 ± 2.5%, 45.4 ± 1.9%, and 62.4 ± 2.2%) were processed through powder metallurgy and characterized to study their mechanical properties. Different porosities were obtained by utilizing different mass fractions of space holder camphene. Camphene was removed by sublimation before sintering and contributed to processing porous Mg with high purity and small average pore size. The average pore size increased from 5.2 µm to 15.1 µm with increase of the porosity from 28.4 ± 1.8% to 62.4 ± 2.2%. Compressive strain-stress data showed that the strain hardening rate, yield strength, and ultimate compressive strength decreased with increase of the porosity. The theoretical yield strength of porous Mg obtained using the Gibson-Ashby model agreed with experimental data.

  9. Scaleup of powder metallurgy processed Nb-Al multifilamentary wire

    International Nuclear Information System (INIS)

    Thieme, C.; Foner, S.; Otubo, J.; Pourrahimi, S.; Schwartz, B.; Zhang, H.

    1983-01-01

    Power metallurgy processed Nb-Al superconducting wires were fabricated from billets up to 45 mm o.d. with nominal areal reduction ratios, R, up to 2 X 10 5 , Nb powder sizes from 40 to 300 μm from various sources, Al powder sizes from 9 to 75 μm, Al concentrations from 3 to 25 wt % Al and with a wide range of heat treatments. All the compacts used tap density powder in a Cu tube and swaging and/or rod rolling and subsequent wire drawing. Both single strand and bundled wires were made. Overall critical current densities, J /SUB c/, of 2 X 10 4 A/cm 2 at 14 T and 10 4 A/cm 2 at 16 T were achieved for 6 to 8 wt % Al in Nb

  10. A review of experiment data processing method for uranium mining and metallurgy in BRICEM

    International Nuclear Information System (INIS)

    Ye Guoqiang; Lu Kehong; Wang Congying

    1997-01-01

    The authors investigates the methods of experiment data processing in Beijing Research Institute of Chemical Engineering and Metallurgy (BRICEM). It turns out that error analysis method is used to process experiment data, single-factor transformation and orthogonal test design method are adopted for arranging test, and regression analysis and mathematical process simulation are applied to process mathematical model for uranium mining and metallurgy. The methods above-mentioned lay a foundation for the utilization of mathematical statistics in our subject

  11. Industrial powder metallurgy processing for production of high field Nb3Sn

    International Nuclear Information System (INIS)

    Hecker, A.; Gregory, E.; Wong, J.; Thieme, C.L.H.; Foner, S.

    1988-01-01

    Technology transfer is discussed for fabricating Nb 3 Sn(Ti) via powder metallurgy methods from laboratory scale production at MIT to industrial production at Supercon Inc. Industrial production techniques such as hydrostatic extrusion and drawing have produced superconducting wires with promising critical current densities in preliminary field measurements. Initial steps toward process modification and optimization to improve the commercial feasibility of the powder metallurgy process are evaluated. These modifications are aimed at reducing production time and increasing process flexibility

  12. Preparation of magnesium metal matrix composites by powder metallurgy process

    Science.gov (United States)

    Satish, J.; Satish, K. G., Dr.

    2018-02-01

    Magnesium is the lightest metal used as the source for constructional alloys. Today Magnesium based metal matrix composites are widely used in aerospace, structural, oceanic and automobile applications for its light weight, low density(two thirds that of aluminium), good high temperature mechanical properties and good to excellent corrosion resistance. The reason of designing metal matrix composite is to put in the attractive attributes of metals and ceramics to the base metal. In this study magnesium metal matrix hybrid composite are developed by reinforcing pure magnesium with silicon carbide (SiC) and aluminium oxide by method of powder metallurgy. This method is less expensive and very efficient. The Hardness test was performed on the specimens prepared by powder metallurgy method. The results revealed that the micro hardness of composites was increased with the addition of silicon carbide and alumina particles in magnesium metal matrix composites.

  13. Introduction to powder metallurgy processes for titanium manufacturing; Introduccion al procesado pulvimetalurgico del titanio

    Energy Technology Data Exchange (ETDEWEB)

    Esteban, P. G.; Bolzoni, L.; Ruiz-Navas, E. M.; Gordo, E.

    2011-07-01

    The development of new extraction processes to produce titanium in powder form leads Powder Metallurgy to an advantage position among the manufacturing processes for titanium. The cost reduction of base material, coupled with the economy of the powder metallurgy processes, give titanium industry the chance to diversify its products, which could lead to production volumes able to stabilise the price of the metal. This work reviews some of the Powder Metallurgy techniques for the manufacturing of titanium parts, and describes the two typical approaches for titanium manufacturing: Blending Elemental and Prealloyed Powders. Among others, conventional pressing and sintering are described, which are compared with cold and hot isostatic pressing techniques. Real and potential applications are described. (Author) 71 refs.

  14. Oxidation of adsorbed ferrous iron: kinetics and influence of process conditions.

    Science.gov (United States)

    Buamah, R; Petrusevski, B; Schippers, J C

    2009-01-01

    For the removal of iron from groundwater, aeration followed with rapid (sand) filtration is frequently applied. Iron removal in this process is achieved through oxidation of Fe(2 + ) in aqueous solution followed by floc formation as well as adsorption of Fe(2 + ) onto the filter media. The rate of oxidation of the adsorbed Fe(2 + ) on the filter media plays an important role in this removal process. This study focuses on investigating the effect of pH on the rate of oxidation of adsorbed Fe(2 + ). Fe(2 + ) has been adsorbed, under anoxic conditions, on iron oxide coated sand (IOCS) in a short filter column and subsequently oxidized by feeding the column with aerated water. Ferrous ions adsorbed at pH 5, 6, 7 and 8 demonstrated consumption of oxygen, when aerated water was fed into the column. The oxygen uptake at pH 7 and 8 was faster than at pH 5 and 6. However the difference was less pronounced than expected. The difference is attributed to the pH buffering effect of the IOCS. At feedwater pH 5, 6 and 7 the pH in the effluent was higher than in the influent, while a pH drop should occur because of oxidation of adsorbed Fe(2 + ). At pH 8, the pH dropped. These phenomena are attributed to the presence of calcium and /or ferrous carbonate in IOCS.

  15. Development of new metal matrix composite electrodes for electrical discharge machining through powder metallurgy process

    Directory of Open Access Journals (Sweden)

    C. Mathalai Sundaram

    2014-12-01

    Full Text Available Electrical discharge machining (EDM is one of the widely used nontraditional machining methods to produce die cavities by the erosive effect of electrical discharges. This method is popular due to the fact that a relatively soft electrically conductive tool electrode can machine hard work piece. Copper electrode is normally used for machining process. Electrode wear rate is the major drawback for EDM researchers. This research focus on fabrication of metal matrix composite (MMC electrode by mixing copper powder with titanium carbide (TiC and Tungsten carbide (WC powder through powder metallurgy process, Copper powder is the major amount of mixing proportion with TiC and WC. However, this paper focus on the early stage of the project where powder metallurgy route was used to determine suitable mixing time, compaction pressure and sintering and compacting process in producing EDM electrode. The newly prepared composite electrodes in different composition are tested in EDM for OHNS steel.

  16. PROCESSING OF SOFT MAGNETIC MATERIALS BY POWDER METALLURGY AND ANALYSIS OF THEIR PERFORMANCE IN ELECTRICAL MACHINES

    Directory of Open Access Journals (Sweden)

    W. H. D. Luna

    2017-12-01

    Full Text Available This article presents the use of finite elements to analyze the yield of electric machines based on the use of different soft magnetic materials for the rotor and the stator, in order to verify the performance in electric machine using powder metallurgy. Traditionally, the cores of electric machines are built from rolled steel plates, thus the cores developed in this work are obtained from an alternative process known as powder metallurgy, where powders of soft magnetic materials are compacted and sintered. The properties of interest were analyzed (magnetic, electric and mechanical properties and they were introduced into the software database. The topology of the rotor used was 400 W three-phase synchronous motor manufactured by WEG Motors. The results show the feasibility to replace the metal sheets of the electric machines by solid blocks obtained by powder metallurgy process with only 0.37% yield losses. In addition, the powder metallurgical process reduces the use of raw materials and energy consumption per kg of raw material processed.

  17. Investigation of a thermoplastic-powder metallurgy process for the fabrication of porous niobium rods

    International Nuclear Information System (INIS)

    Nordin, D.R.

    1978-06-01

    The feasibility of using a thermoplastic-powder metallurgy technique for the fabrication of porous niobium rods was investigated. Some early problems were overcome to successfully extrude the polymer coated niobium powder into long lengths. The effects of certain process variables were investigated. Residual porosity and extrusion pressure were found to be regulated by the polymer fraction. The procedures for taking the extruded polystyrene--niobium rods through the heat treatments to the final, tin infiltrated stage are explained

  18. Reaction mechanisms and evaluation of effective process operation for catalytic oxidation and coagulation by ferrous solution and hydrogen peroxide

    Energy Technology Data Exchange (ETDEWEB)

    Lee, S.H.; Moon, H.J.; Kim, Y.M. [Dept. of Environmental Engineering, Sangmyung Univ., Cheonan (Korea); Bae, W.K. [Dept. of Civil and Environmental Engineering, Hanyang Univ., Ansan, Kyounggi (Korea)

    2003-07-01

    This research was carried out to evaluate the removal efficiencies of COD{sub cr} and colour for the dyeing wastewater by ferrous solution and the different dosage of H{sub 2}O{sub 2} in Fenton process. In the case of H{sub 2}O{sub 2} divided dosage, 7:3 was more effective than 3:7 to remove COD{sub cr} and colour. The results showed that COD was mainly removed by Fenton coagulation, where the ferric ions are formed in the initial step of Fenton reaction. On the other hand colour was removed by Fenton oxidation rather than Fenton coagulation. This paper also aims at pursuing to investigate the effective removal mechanisms using ferrous ion coagulation, ferric ion coagulation and Fenton oxidation process. The removal mechanism of COD{sub cr} and colour was mainly coagulation by ferrous ion, ferric ion and Fenton oxidation. The removal efficiencies were dependent on the ferric ion amount at the beginning of the reaction. However the final removal efficiency of COD and colour was in the order of Fenton oxidation, ferric ion coagulation and ferrous ion coagulation. The reason of the highest removal efficiency by Fenton oxidation can be explained by the chain reactions with ferrous solution, ferric ion and hydrogen peroxide. (orig.)

  19. Mechanical properties of AZ31 alloy processed by a green metallurgy route

    International Nuclear Information System (INIS)

    D'Enrico, F.; Garces, G.; Hofer, M.; Kim, S. K.; Perez, P.; Cabeza, S.; Adeva, P.

    2013-01-01

    Recently it has been proved that molding of defect-free components of various commercial alloys of magnesium can be carried out successfully when small amounts of CaO are added to the melt, making unnecessary the use of SF 6 coverage. In the case of AZ alloys, this process also remarkably improves their mechanical properties not only by the greater cleaning of alloys but also by the formation of CaAl 2 phase. This work, part of the Green project Metallurgy (http://www.green-metallurgy.eu) funded by the European Union (LIFE+2009), studies the influence of different CaO additions on the microstructure and mechanical properties of AZ31 Eco-Mg alloy. The alloy was processed by a conventional route involving extrusion of as-cast rods as well as by a powder metallurgy route (PM) using chips as starting material. The objective was to analyze the viability of recycling machining chips to manufacture components for the automobile industry and transportation in general, because of its low cost and environmental impact. It has been demonstrated that alloys processed from chips exhibit the highest tensile stress values, close to 320 MPa. (Author)

  20. Properties of WZ21 (%wt) alloy processed by a powder metallurgy route.

    Science.gov (United States)

    Cabeza, Sandra; Garcés, Gerardo; Pérez, Pablo; Adeva, Paloma

    2015-06-01

    Microstructure, mechanical properties and corrosion behaviour of WZ21 (%wt) alloy prepared by a powder metallurgy route from rapidly solidified powders have been studied. Results were compared to those of the same alloy prepared through a conventional route of casting and extrusion. The microstructure of the extruded ingot consisted of α-Mg grains and Mg3Zn3Y2 (W-phase) and LPSO-phase particles located at grain boundaries. Moreover, stacking faults were also observed within α-Mg grains. The alloy processed by the powder metallurgy route exhibited a more homogeneous and finer microstructure, with a grain size of 2 μm. In this case W-phase and Mg24Y5 phase were identified, but not the LPSO-phase. The microstructural refinement induced by the use of rapidly solidified powders strengthened the alloy at room temperature and promoted superplasticity at higher strain rates. Corrosion behaviour in PBS medium evidenced certain physical barrier effect of the almost continuous arrangements of second phases aligned along the extrusion direction in conventionally processed WZ21 alloy, with a stable tendency around 7 mm/year. On the other hand, powder metallurgy processing promoted significant pitting corrosion, inducing accelerated corrosion rate during prolonged immersion times. Copyright © 2015 Elsevier Ltd. All rights reserved.

  1. A sustainable process to utilize ferrous sulfate waste from titanium oxide industry by reductive decomposition reaction with pyrite

    International Nuclear Information System (INIS)

    Huang, Penghui; Deng, Shaogang; Zhang, Zhiye; Wang, Xinlong; Chen, Xiaodong; Yang, Xiushan; Yang, Lin

    2015-01-01

    Highlights: • A newly developed treating process of ferrous sulfate was proposed. • The reaction process was discussed by thermodynamic analysis. • Thermodynamic analysis was compared with experiments results. • The kinetic model of the decomposition reaction was determined. • The reaction mechanism of autocatalytic reactions was explored. - Abstract: Ferrous sulfate waste has become a bottleneck in the sustainable development of the titanium dioxide industry in China. In this study, we propose a new method for the reductive decomposition of ferrous sulfate waste using pyrite. Thermodynamics analysis, tubular reactor experiments, and kinetics analysis were performed to analyze the reaction process. The results of the thermodynamic simulation showed that the reaction process and products were different when molar ratio of FeSO_4/FeS_2 was changed. The suitable molar ratio of FeSO_4/FeS_2 was 8–12. The reaction temperature of ferrous sulfate with pyrite was 580–770 K and the main products were Fe_3O_4 and SO_2. The simulation results agreed well with the experimental results. The desulphurization rate reached 98.55% and main solid products were Fe_3O_4 at 823.15 K when mole ratio of FeSO_4/FeS_2 was 8. Nano-sized magnetite was obtained at this condition. The kinetic model was investigated by isoconversional methods. The average E value was 244.34 kJ mol"−"1. The ferrous sulfate decomposition process can be treated as autocatalytic reaction mechanism, which corresponded to the expanded Prout–Tompson (Bna) model. The reaction mechanism of autocatalytic reactions during the process of ferrous sulfate decomposition were explored, the products of Fe oxide substances are the catalyst components.

  2. Interactions of hydrazine, ferrous sulfamate, sodium nitrite, and nitric acid in nuclear fuel processing solutions

    International Nuclear Information System (INIS)

    Gray, L.W.

    1977-03-01

    Hydrazine and ferrous sulfamate are used as reductants in a variety of nuclear fuel processing solutions. An oxidant, normally sodium nitrite, must frequently be added to these nitric acid solutions before additional processing can proceed. The interactions of these four chemicals have been studied under a wide variety of conditions using a 2/sup p/ factorial experimental design to determine relative reaction rates for desired reactions and side reactions. Evidence for a hydrazine-stabilized, sulfamic acid--nitrous acid intermediate was obtained; this intermediate can hydrolyze to ammonia or decompose to nitrogen. The oxidation of Fe 2+ by NO 2 - was shown to proceed at about the same rate as the scavenging of NO 2 - by sulfamic acid. Various side reactions are discussed

  3. Powder metallurgy and fabricating processes of cermet and metmet fuel in Russia

    International Nuclear Information System (INIS)

    Vatulin, A.; Konovalov, I.; Savchenco, A.; Stetsky, Y.; Trifonov, Y.; Bochvar, A.A.

    2000-01-01

    Methods of powder metallurgy are widely used for manufacturing of various components of reactor core: beryllium reflectors, absorbers, parts of controlling and safety systems, fuel pellets for fuel elements of power reactors and etc. The new problems arising before atomic engineering associated with increasing requirements to safe operation of reactors, non-proliferation of the nuclear weapons and utilization of plutonium stockpile in the world, served as a push to development of new kinds of dispersion nuclear fuel CERMET, CERCER, METMET. The bases of fabricating processes of such compositions are the methods of powder metallurgy. In this report some results of research activities on the development of new kinds of CERMET and METMET fuel and fuel elements for different type reactors are presented. (author)

  4. Plutonium-uranium separation in the Purex process using mixtures of hydroxylamine nitrate and ferrous sulfamate

    International Nuclear Information System (INIS)

    McKibben, J.M.; Chostner, D.F.; Orebaugh, E.G.

    1983-11-01

    Laboratory studies, followed by plant operation, established that a mixture of hydroxylamine nitrate (HAN) and ferrous sulfamate (FS) is superior to FS used alone as a reductant for plutonium in the Purex first cycle. FS usage has been reduced by about 70% (from 0.12 to 0.04M) compared to the pre-1978 period. This reduced the volume of neutralized waste due to FS by 194 liters/metric ton of uranium (MTU) processed. The new flowsheet also gives lower plutonium losses to waste and at least comparable fission product decontamination. To achieve satisfactory performance at this low concentration of FS, the acidity in the 1B mixer-settler was reduced by using a split-scrub - a low acid scrub in stage one and a higher acid scrub in stage three - to remove acid from the solvent exiting the 1A centrifugal contactor. 8 references, 14 figures, 1 table

  5. Ferrous Sulfate (Iron)

    Science.gov (United States)

    ... are allergic to ferrous sulfate, any other medications tartrazine (a yellow dye in some processed foods and ... in, tightly closed, and out of reach of children. Store it at room temperature and away from ...

  6. Combined process "helical rolling-pressing" and its effect on the microstructure of ferrous and non-ferrous materials

    Science.gov (United States)

    Naizabekov, Abdrakhman; Lezhnev, Sergey; Arbuz, Alexandr; Panin, Evgeniy

    2018-02-01

    Ultrafine-grained materials are one of the most promising structural and functional materials. However, the known methods of obtaining them are not enough powerful and technologically advanced for profitable industrial applications. Development of the combined process "helical rolling-pressing" is an attempt to bring technology to produce ultrafine-grained materials to the industry. The combination of intense processing of the surface by helical rolling and the entire cross section of workpiece in equal channel angular matrix, with intense deformation by torsion between rolls and matrix will increase the degree of deformation per pass and allows to mutually compensate disadvantages of these methods in the case of their separate use. This paper describes the development of a laboratory stand and study of influence of combined process "helical rolling-pressing"on the microstructure of tool steel, technical copper and high alloy stainless high-temperature steel.

  7. Powder metallurgy processing of high strength turbine disk alloys

    Science.gov (United States)

    Evans, D. J.

    1976-01-01

    Using vacuum-atomized AF2-1DA and Mar-M432 powders, full-scale gas turbine engine disks were fabricated by hot isostatically pressing (HIP) billets which were then isothermally forged using the Pratt & Whitney Aircraft GATORIZING forging process. While a sound forging was produced in the AF2-1DA, a container leak had occurred in the Mar-M432 billet during HIP. This resulted in billet cracking during forging. In-process control procedures were developed to identify such leaks. The AF2-1DA forging was heat treated and metallographic and mechanical property evaluation was performed. Mechanical properties exceeded those of Astroloy, one of the highest temperature capability turbine disk alloys presently used.

  8. Thermal processing of diblock copolymer melts mimics metallurgy

    Science.gov (United States)

    Kim, Kyungtae; Schulze, Morgan W.; Arora, Akash; Lewis, Ronald M.; Hillmyer, Marc A.; Dorfman, Kevin D.; Bates, Frank S.

    2017-05-01

    Small-angle x-ray scattering experiments conducted with compositionally asymmetric low molar mass poly(isoprene)-b-poly(lactide) diblock copolymers reveal an extraordinary thermal history dependence. The development of distinct periodic crystalline or aperiodic quasicrystalline states depends on how specimens are cooled from the disordered state to temperatures below the order-disorder transition temperature. Whereas direct cooling leads to the formation of documented morphologies, rapidly quenched samples that are then heated from low temperature form the hexagonal C14 and cubic C15 Laves phases commonly found in metal alloys. Self-consistent mean-field theory calculations show that these, and other associated Frank-Kasper phases, have nearly degenerate free energies, suggesting that processing history drives the material into long-lived metastable states defined by self-assembled particles with discrete populations of volumes and polyhedral shapes.

  9. Influence of process variables on biooxidation of ferrous sulfate by an indigenous Acidithiobacillus ferrooxidans. Part I: Flask experiments

    Energy Technology Data Exchange (ETDEWEB)

    S.M. Mousavi; S. Yaghmaei; F. Salimi; A. Jafari [Sharif University of Technology, Tehran (Iran). Department of Chemical and Petroleum Engineering

    2006-12-15

    Biological oxidation of ferrous sulfate by Acidithiobacillus ferrooxidans has proved to be a significant step in the bioleaching of sulfide minerals and the treatment of acid mine drainage. The same bioreaction also has beneficial applications in the desulphurization of coal and removal of hydrogen sulfide from gaseous effluents. In this research, the effects of some process variables such as pH, temperature, elemental sulfur, amount of initial ferrous and magnesium ions on oxidation of ferrous sulfate by a native A. ferrooxidans, which was isolated from a chalcopyrite concentrate, were investigated. All experiments carried out in shake flasks at 33{sup o}C that was obtained as optimum temperature for the specific bacterial growth rate. The optimum range of pH for the maximum growth of the cells and effective biooxidation of ferrous sulfate varied from 2 to 2.3. The maximum biooxidation rate was achieved 1.2 g/L h in a culture initially containing 20.2 g/L Fe{sup 2+}. Mg{sup 2+} from 20 mg/L to 120 mg/L did not have any effect on the efficiency of the process, while the presence of elemental sulfur had negative effect on the biooxidation. 16 refs., 8 figs.

  10. Development of processes for zircaloy chips recycling by electric arc furnace remelting and powder metallurgy

    International Nuclear Information System (INIS)

    Pereira, Luiz Alberto Tavares

    2014-01-01

    PWR reactors employ, as nuclear fuel, UO 2 pellets with Zircaloy clad. In the fabrication of fuel element parts, machining chips from the alloys are generated. As the Zircaloy chips cannot be discarded as ordinary metallic waste, the recycling of this material is important for the Brazilian Nuclear Policy, which targets the reprocess of Zircaloy residues for economic and environmental aspects. This work presents two methods developed in order to recycle Zircaloy chips. In one of the methods, Zircaloy machining chips were refused using an electric-arc furnace to obtain small laboratory ingots. The second one uses powder metallurgy techniques, where the chips were submitted to hydriding process and the resulting material was milled, isostatically pressed and vacuum sintered. The ingots were heat-treated by vacuum annealing. The microstructures resulting from both processing methods were characterized using optical and scanning electron microscopy. Chemical composition, crystal phases and hardness were also determined. The results showed that the composition of recycled Zircaloy comply with the chemical specifications and presented adequate microstructure for nuclear use. The good results of the powder metallurgy method suggest the possibility of producing small parts, like cladding end-caps, using near net shape sintering. (author)

  11. A Novel Process for Joining Ti Alloy and Al Alloy using Two-Stage Sintering Powder Metallurgy

    Science.gov (United States)

    Long, Luping; Liu, Wensheng; Ma, Yunzhu; Wu, Lei; Liu, Chao

    2018-04-01

    The major challenges for conventional diffusion bonding of joining Ti alloy and Al alloy are the undesirable interfacial reaction, low matrixes and joint strength. To avoid the problem in diffusion bonding, a novel two-stage sintering powder metallurgy process is developed. In the present work, the interface characterization and joint performance of the bonds obtained by powder metallurgy bonding are investigated and are compared with the diffusion bonded Ti/Al joints obtained with the same and the optimized process parameters. The results show that no intermetallic compound is visible in the Ti/Al joint obtained by powder metallurgy bonding, while a new layer formed at the joint diffusion bonded with the same parameters. The maximum tensile strength of joint obtained by diffusion bonding is 58 MPa, while a higher tensile strength reaching 111 MPa for a bond made by powder metallurgy bonding. Brittle fractures occur at all the bonds. It is shown that the powder metallurgy bonding of Ti/Al is better than diffusion bonding. The results of this study should benefit the bonding quality.

  12. Influence of thermo-mechanical processing on the microstructure of Cu-based shape memory alloys produced by powder metallurgy

    International Nuclear Information System (INIS)

    Rodriguez, P.P.; Ibarra, A.; Iza-Mendia, A.; Recarte, V.; Perez-Landazabal, J.I.; San Juan, J.; No, M.L.

    2003-01-01

    Cu-Al-Ni shape memory alloys processed by powder metallurgy show very good thermo-mechanical properties, much better than those found in alloys produced by conventional casting. In this paper, we present the microstructural characterisation of these powder metallurgy alloys in order to find the microscopic mechanisms, linked to the powder metallurgy processing method, which are indeed responsible of such good thermo-mechanical behaviour. Electron microscopy studies [scanning electron microscopy (SEM), electron backscatter diffraction (EBSD) and transmission electron microscopy (TEM)] show that powder metallurgy processing creates a sub-grain structure characterised by the presence of low angle sub-boundaries. These sub-boundaries are found to be lying on {1 1 0} and {1 1 2} lattice planes and are composed by an arrangement of superdislocations. These sub-boundaries may improve ductility in two ways: acting as a sink of dislocations which promotes plastic deformation and decreasing stress concentration at grain boundaries. Moreover, since sub-boundaries act as weak obstacles for the movement of martensite plates, the improvement on ductility is accomplished by an adequate thermo-mechanical behaviour

  13. Characterization of Powder Metallurgy Processed Pure Magnesium Materials for Biomedical Applications

    Directory of Open Access Journals (Sweden)

    Matěj Březina

    2017-10-01

    Full Text Available Magnesium with its mechanical properties and nontoxicity is predetermined as a material for biomedical applications; however, its high reactivity is a limiting factor for its usage. Powder metallurgy is one of the promising methods for the enhancement of material mechanical properties and, due to the introduced plastic deformation, can also have a positive influence on corrosion resistance. Pure magnesium samples were prepared via powder metallurgy. Compacting pressures from 100 MPa to 500 MPa were used for samples’ preparation at room temperature and elevated temperatures. The microstructure of the obtained compacts was analyzed in terms of microscopy. The three-point bendisng test and microhardness testing were adopted to define the compacts’ mechanical properties, discussing the results with respect to fractographic analysis. Electrochemical corrosion properties analyzed with electrochemical impedance spectroscopy carried out in HBSS (Hank’s Balanced Salt Solution and enriched HBSS were correlated with the metallographic analysis of the corrosion process. Cold compacted materials were very brittle with low strength (up to 50 MPa and microhardness (up to 50 HV (load: 0.025 kg and degraded rapidly in both solutions. Hot pressed materials yielded much higher strength (up to 250 MPa and microhardness (up to 65 HV (load: 0.025 kg, and the electrochemical characteristics were significantly better when compared to the cold compacted samples. Temperatures of 300 °C and 400 °C and high compacting pressures from 300 MPa to 500 MPa had a positive influence on material bonding, mechanical and electrochemical properties. A compacting temperature of 500 °C had a detrimental effect on material compaction when using pressure above 200 MPa.

  14. New radiation technologies and methods for control of technological processes in metallurgy

    International Nuclear Information System (INIS)

    Zaykin, Yu.

    1996-01-01

    Radiation Technology of Metal and Ceramic Production with Enhanced Service Properties. Based on application of radiation technique in powder metallurgy the new technology for obtaining metals, alloys and ceramic materials with high service properties is worked out. Radiation processing of powder materials at the certain stage of the process leads to profound structure alterations at all further stages and eventually effects the properties of the resulting product. Theoretical calculation and experimental studies of electron-positron annihilation in powder-pressed samples showed that irradiation caused powder particles surface state changes favorable for further sintering and crystallization processes development. It is shown that irradiation of metal powders and powder-pressed samples by high energy electrons is technologically most efficient. The right choice of the type-and the mode of the radiation processing makes it possible to obtain metals, alloys and ceramic materials (Mo,Fe, W, Al, Ni, Cu, stainless steels, ceramics, etc.) with homogeneous structure and stable enhanced service properties. The project on radiation technology application to powder metallurgy represented by a group of authors was awarded with the diploma and the gold medal at the 22 International Exhibition of Inventions (Geneva, 1994). New Technologic Opportunities of the Chromium-Nickel Alloys Processing To obtain the required phase-structure state special methods of the chromium-nickel alloy processing for sensitive elastic devices production were worked out combining plastic deformation, thermal and radiation processing. It is shown that h-gbb phase transfer not observed before is possible in extremely non-equilibrium conditions under electron irradiation. It is established that the complex reaction of recrystallization and gb-phase deposition proceeds under electron irradiation at the room temperature when the certain threshold plastic deformation degree is reached that leads to the same

  15. Fast neutron activation analysis in metallurgy

    International Nuclear Information System (INIS)

    Sterlinski, S.

    1981-01-01

    Article discusses the usage of a 14 MeV neutron generator for producing fast neutrons of different energies and intensities. A complete instrumental set-up for the neutron activation analysis (NAA) is given. In metallurgy the device is mainly used in the determination of oxygen and silicon in steel and non-ferrous metal, including different alloys

  16. Superconductors by powder metallurgy techniques

    International Nuclear Information System (INIS)

    Pickus, M.R.; Wang, J.L.F.

    1976-05-01

    Fabrication methods for Nb 3 Sn type compounds are described. Information is included on the Bell Telephone process, the General Electric tape process, superconductor stability, the bronze process, powder metallurgy multifilamentary tapes and wires, and current assessment of powder metallurgy superconducting wire

  17. Copper-carbon and aluminum-carbon composites fabricated by powder metallurgy processes

    International Nuclear Information System (INIS)

    Silvain, Jean-François; Veillère, Amélie; Lu, Yongfeng

    2014-01-01

    The increase in both power and packing densities in power electronic devices has led to an increase in the market demand for effective heat-dissipating materials, with high thermal conductivity and thermal- expansion coefficient compatible with chip materials still ensuring the reliability of the power modules. In this context, metal matrix composites: carbon fibers and diamond-reinforced copper and aluminum matrix composites among them are considered very promising as a next generation of thermal-management materials in power electronic packages. These composites exhibit enhanced thermal properties compared to pure copper combined with lower density. This article presents the fabrication techniques of copper/carbon fibers and copper/diamond and aluminum/carbon fibers composite films by powder metallurgy and hot pressing. The thermal analyses clearly indicate that interfacial treatments are required in these composites to achieve high thermomechanical properties. Interfaces (through novel chemical and processing methods), when selected carefully and processed properly will form the right chemical/mechanical link between metal and carbon, enhancing all the desired thermal properties while minimizing the deleterious effect.

  18. Fabrication of Fe-Cr-Mo powder metallurgy steel via a mechanical-alloying process

    Science.gov (United States)

    Park, Jooyoung; Jeong, Gowoon; Kang, Singon; Lee, Seok-Jae; Choi, Hyunjoo

    2015-11-01

    In this study, we employed a mechanical-alloying process to manufacture low-alloy CrL and CrM steel powders that have similar specifications to their water-atomized counterparts. X-ray diffraction showed that Mo and Cr are alloyed in Fe after four cycles of planetary milling for 1 h at 150 RPM with 15-min pauses between the cycles (designated as P2C4 process). Furthermore, the measured powder size was found to be similar to that of the water-atomized counterparts according to both scanning electron microscope images and laser particle size analysis. The samples were sintered at 1120 °C, after which the P2C4-milled CrL showed similar hardness to that of water-atomized CrL, whereas the P2C4-milled CrM showed about 45% lower hardness than that of its water-atomized counterpart. Water-atomized CrM consists of a well-developed lathtype microstructure (bainite or martensite), while a higher fraction of polygonal ferrite is observed in P2C4-milled CrM. This phase difference causes the reduction of hardness in the P2C4-milled CrM, implying that the phase transformation behavior of specimens produced via powder metallurgy is influenced by the powder fabrication method.

  19. Effects of Post-Sinter Processing on an Al–Zn–Mg–Cu Powder Metallurgy Alloy

    Directory of Open Access Journals (Sweden)

    Matthew David Harding

    2017-09-01

    Full Text Available The objective of this work was to study the effects of several post-sinter processing operations (heat-treatment, sizing, shot peening on a press-and-sinter 7xxx series aluminum powder metallurgy (PM alloy. The characterization of the products was completed through a combination of non-contact surface profiling, hardness measurements, differential scanning calorimetry (DSC, transmission electron microscopy (TEM, X-ray diffraction (XRD, tensile, and three-point bend fatigue testing. It was determined that sizing in the as-quenched state imparted appreciable reductions in surface hardness (78 HRB and fatigue strength (168 MPa relative to counterpart specimens that were sized prior to solutionizing (85 HRB and 228 MPa. These declines in performance were ascribed to the annihilation of quenched in vacancies that subsequently altered the nature of precipitates within the finished product. The system responded well to shot peening, as this process increased fatigue strength to 294 MPa. However, thermal exposure at 353 K (80 °C and 433 K (160 °C then reduced fatigue performance to 260 MPa and 173 MPa, respectively, as a result of residual stress relaxation and in-situ over-aging.

  20. Performance of nitrate-dependent anaerobic ferrous oxidizing (NAFO) process: a novel prospective technology for autotrophic denitrification.

    Science.gov (United States)

    Zhang, Meng; Zheng, Ping; Li, Wei; Wang, Ru; Ding, Shuang; Abbas, Ghulam

    2015-03-01

    Nitrate-dependent anaerobic ferrous oxidizing (NAFO) is a valuable biological process, which utilizes ferrous iron to convert nitrate into nitrogen gas, removing nitrogen from wastewater. In this work, the performance of NAFO process was investigated as a nitrate removal technology. The results showed that NAFO system was feasible for autotrophic denitrification. The volumetric loading rate (VLR) and volumetric removal rate (VRR) under steady state were 0.159±0.01 kg-N/(m(3) d) and 0.073±0.01 kg-N/(m(3) d), respectively. In NAFO system, the effluent pH was suggested as an indicator which demonstrated a good correlation with nitrogen removal. The nitrate concentration was preferred to be less than 130 mg-N/L. Organic matters had little influence on NAFO performance. Abundant iron compounds were revealed to accumulate in NAFO sludge with peak value of 51.73% (wt), and they could be recycled for phosphorus removal, with capacity of 16.57 mg-P/g VS and removal rate of 94.77±2.97%, respectively. Copyright © 2014 Elsevier Ltd. All rights reserved.

  1. Application of powder metallurgy and hot rolling processes for manufacturing aluminum/alumina composite strips

    Energy Technology Data Exchange (ETDEWEB)

    Zabihi, Majed, E-mail: m.zabihi@ma.iut.ac.ir [Department of Materials Engineering, Isfahan University of Technology, Isfahan 84156-83111 (Iran, Islamic Republic of); Toroghinejad, Mohammad Reza, E-mail: toroghi@cc.iut.ac.ir [Department of Materials Engineering, Isfahan University of Technology, Isfahan 84156-83111 (Iran, Islamic Republic of); Shafyei, Ali, E-mail: shafyei@cc.iut.ac.ir [Department of Materials Engineering, Isfahan University of Technology, Isfahan 84156-83111 (Iran, Islamic Republic of)

    2013-01-10

    In this study, aluminum matrix composites (AMC) with 2, 4, 6 and 10 wt% alumina were produced using powder metallurgy (PM), mechanical milling (MM) and vacuum hot pressing (VHP) techniques; then, this was followed by the hot-rolling process. During hot rolling, AMCs with 6 and 10 wt% Al{sub 2}O{sub 3} were fractured whereas strip composites with 2 and 4 wt% Al{sub 2}O{sub 3} were produced successfully. Microstructure and mechanical properties of the samples were investigated by optical and scanning electron microscopes and tensile and hardness tests, respectively. Microscopic evaluations of the hot-rolled composites showed a uniform distribution of alumina particles in the aluminum matrix. It was found that with increasing alumina content in the matrix, tensile strength (TS) and hardness increased and the percentage of elongation also decreased. Scanning electron microscope (SEM) was used to investigate aluminum/alumina interfaces and fracture surfaces of the hot rolled specimens after tensile test. SEM observations demonstrated that the failure mode in the hot-rolled Al-2 wt% Al{sub 2}O{sub 3} composite strips is a typical ductile fracture, while the failure mode was shear ductile fracture with more flat surfaces in Al-4 wt% Al{sub 2}O{sub 3} strips.

  2. Processing, characterization, and in vitro/in vivo evaluations of powder metallurgy processed Ti-13Nb-13Zr alloys.

    Science.gov (United States)

    Bottino, Marco C; Coelho, Paulo G; Henriques, Vinicius A R; Higa, Olga Z; Bressiani, Ana H A; Bressiani, José C

    2009-03-01

    This article presents details of processing, characterization and in vitro as well as in vivo evaluations of powder metallurgy processed Ti-13Nb-13Zr samples with different levels of porosity. Sintered samples were characterized for density, crystalline phases (XRD), and microstructure (SEM and EDX). Samples sintered at 1000 degrees C showed the highest porosity level ( approximately 30%), featuring open and interconnected pores ranging from 50 to 100 mum in diameter but incomplete densification. In contrast, samples sintered at 1300 and 1500 degrees C demonstrated high densification with 10% porosity level distributed in a homogeneous microstructure. The different sintering conditions used in this study demonstrated a coherent trend that is increase in temperature lead to higher sample densification, even though densification represents a drawback for bone ingrowth. Cytotoxicity tests did not reveal any toxic effects of the starting and processed materials on surviving cell percentage. After an 8-week healing period in rabbit tibias, the implants were retrieved, processed for nondecalcified histological evaluation, and then assessed by backscattered electron images (BSEI-SEM) and EDX. Bone growth into the microstructure was observed only in samples sintered at 1000 degrees C. Overall, a close relation between newly formed bone and all processed samples was observed. (c) 2008 Wiley Periodicals, Inc.

  3. Metallurgy Department

    DEFF Research Database (Denmark)

    Risø National Laboratory, Roskilde

    The activities of the Metallurgy Department at Risø during 1981 are described. The work is presented in three chapters: General Materials Research, Technology and Materials Development, Fuel Elements. Furthermore, a survey is given of the department's participation in international collaboration...

  4. Obtainment of the alloy Cu13Al4Ni using processed by powder metallurgy

    International Nuclear Information System (INIS)

    Grossi, L.J.; Damasceno, N.; Muterlle, P.V.

    2016-01-01

    The powder metallurgy is a technique environmentally advantageous that allows the production of many pieces, with a good superficial finishing and dimensional tolerance. For the production of pieces using technique, basics steps are carried out, as the characterization of powders, the mixing and homogenization, compacting and sintering. In this context, this work has as objective the obtainment of the Cu13Al4Ni alloy via powder metallurgy. For this, was made a high energy milling for 2, 4 and 8 hours. Then, the milled powder was compacted and posteriorly, sintered in an oven with controlled atmosphere. It was observed that the milling time affects directly in sintering of the pieces. The best results obtained were for the samples that were milled for 4 hours. This samples have showed 21, 52% of porosity and 6,382 g/cm³ of the density of sintered. (author)

  5. Characterization of Powder Metallurgy Processed Pure Magnesium Materials for Biomedical Applications

    Czech Academy of Sciences Publication Activity Database

    Březina, M.; Minda, J.; Doležal, P.; Krystýnová, M.; Fintová, Stanislava; Zapletal, J.; Wasserbauer, J.; Ptáček, P.

    2017-01-01

    Roč. 7, č. 11 (2017), č. článku 461. ISSN 2075-4701 Institutional support: RVO:68081723 Keywords : magnesium * powder metallurgy * cold pressing * hot pressing * EIS (Electrochemical impedance spectroscopy) * three-point bending test * corrosion Subject RIV: JK - Corrosion ; Surface Treatment of Materials OBOR OECD: Coating and films Impact factor: 1.984, year: 2016 http://www.mdpi.com/2075-4701/7/11/461

  6. Foundations of powder metallurgy

    International Nuclear Information System (INIS)

    Libenson, G.A.

    1987-01-01

    Consideration is being given to physicochemical foundations and technology of metal powders, moulding and sintering of bars, made of them or their mixtures with nonmetal powders. Data on he design of basic equipment used in the processes of powder metallurgy and its servicing are presented. General requirements of safety engineering when fabricating metal powders and products of them are mentioned

  7. Powder metallurgy - some economic considerations

    Energy Technology Data Exchange (ETDEWEB)

    Kassem, M.E.

    1982-01-01

    As a forming process powder metallurgy offers reductions in material and energy consumption. The engineering prerequisites and economics are discussed in relation to several industrial applications including automobile parts. 14 refs.

  8. High damping Al-Fe-Mo-Si/Zn-Al composites produced by rapidly solidified powder metallurgy process

    International Nuclear Information System (INIS)

    Li, P.Y.; Dai, S.L.; Chai, S.C.; Li, Y.R.

    2000-01-01

    The metallic materials commonly used in aircraft and aerospace fields, such as aluminum and titanium alloys, steels, etc., show extremely low damping capacity (usually of the order of or less than 10 -3 ). Thus, some problems related to vibration may emerge and influence the reliability, safety and life of airplanes, satellites, etc. It has been reported that almost two thirds of errors for rockets and satellites are related to vibration and noise. One effective way to solve these vibration-related problems is to adopt high damping metallic materials. Conventional high damping alloys exhibit damping capacity above 10 -2 , however, their densities are usually great than 5 x 10 3 kg m -3 , or their strengths are less than 200 MPa (for alloys based on dislocation damping), making them impossible to be applied to aircraft and aerospace areas. Recently, some low-density high-damping metal/metal composites based on aluminum and high damping alloys have been developed in Beijing Institute of Aeronautical Materials (BIAM) by the rapidly solidified power metallurgy process. This paper aims to report the properties of the composites based on a high temperature Al-Fe-Mo-Si alloy and a high damping Zn-Al alloy, and compare them with that of 2618-T61 alloy produced by the ingot metallurgy process

  9. The synthesis and characterization of Mg-Zn-Ca alloy by powder metallurgy process

    Energy Technology Data Exchange (ETDEWEB)

    Annur, Dhyah; Franciska, P.L.; Erryani, Aprilia; Amal, M. Ikhlasul; Kartika, Ika, E-mail: pepeng2000@yahoo.com [Research center for Metallurgy and Material, Indonesian Institute of Science (Indonesia); Sitorus, Lyandra S. [Sultan Ageng Tirtayasa University (Indonesia)

    2016-04-19

    Known for its biodegradation and biocompatible properties, magnesium alloys have gained many interests to be researched as implant material. In this study, Mg-3Zn-1Ca, Mg-29Zn-1Ca, and Mg-53Zn-4.3Ca (in wt%) were synthesized by means of powder metallurgy method. The compression strength and corrosion resistance of magnesium alloy were thoroughly examined. The microstructures of the alloy were characterized using optical microscopy, Scanning Electron Microscope, and also X-ray diffraction analysis. The corrosion resistance were evaluated using electrochemical analysis. The result indicated that Mg- Zn- Ca alloy could be synthesized using powder metallurgy method. This study showed that Mg-29Zn-1Ca would make the highest mechanical strength up to 159.81 MPa. Strengthening mechanism can be explained by precipitation hardening and grain refinement mechanism. Phase analysis had shown the formation of α Mg, MgO, and intermetallic phases: Mg2Zn11 and also Ca2Mg6Zn3. However, when the composition of Zn reach 53% weight, the mechanical strength will be decreasing. In addition, all of Mg-Zn-Ca alloy studied here had better corrosion resistance (Ecorr around -1.4 VSCE) than previous study of Mg. This study indicated that Mg- 29Zn- 1Ca alloy can be further analyzed to be a biodegradable implant material.

  10. Bio technologies in extractive metallurgy

    International Nuclear Information System (INIS)

    Morin, D.

    1995-01-01

    The bio technologies processes used (or used in the future) in extractive metallurgy are presented. The most advanced one is the degradation of the metals sulfides (bacteria catalyzing the sulfides oxidation of Au, Cu, U). Two other applications outside the extractive metallurgy are also described: metals fixation by living or dead organic matter and the biological destruction of organic reactants such as cyanides. (A.B.)

  11. Microstructure and microanalysis studies of copper-nickel-tin alloys obtained by conventional powder metallurgy processing

    International Nuclear Information System (INIS)

    Monteiro, Waldemar A.; Carrio, Juan A.G.; Masson, T.J.; Vitor, E.; Abreu, C.D.; Marques, I.M.

    2009-01-01

    The aim of this paper was to analyze the microstructural development in samples of Cu-Ni-Sn alloys (weight %) obtained by powder metallurgy (P/M). The powders were mixed for 1/2 hour. After this, they were pressed, in a cold uniaxial pressing (1000 kPa). In the next step the specimens were sintered at temperatures varying from 650 up to 780 deg C under vacuum. Secondly, the samples were homogenized at 500 deg C for several special times. The alloys were characterized by optical microscopy, electrical conductivity and Vickers hardness. X-rays powder diffraction data were collected for the sintered samples in order to a structural and microstructural analysis. The comparative analysis is based on the sintered density, densification parameter, hardness, macrostructures and microstructures of the samples. (author)

  12. Pyrometallurgical processing for raw materials of heavy non-ferrous metals and furnace for carrying it out. Pyrometallurgisches Verarbeitungsverfahren fuer Rohstoffe schwerer Buntmetalle und Ofen zu dessen Realisierung

    Energy Technology Data Exchange (ETDEWEB)

    Vanjukov, A V; Metschev, V V; Bystrov, V P; Eschov, E I; Vasiliev, M G; Zaitsev, V Y; Romenets, V A; Ivanov, V V; Golik, S Y; Grin-Gnatovsky, E S

    1980-06-04

    Pyrometallurgical processing is described, by which non-ferrous metals are obtained from a melt. The pneumatic mixing of melt material and the oxidation of sulphide and oxide starting material is done by blowing a flow of gas with more than 35% oxygen content into it. The layers of slag, ore and raw metal formed in the furnace can be separated. The construction of the furnace is described in detail. 4 examples complete the description.

  13. Use of ferric- and ferrous-salts in liquid waste treatment processes

    International Nuclear Information System (INIS)

    Efremenkov, V.M.; Toropov, I.G.; Toropova, V.V.; Satsukevich, V.M.; Davidov, J.P.; Jabrodsky, V.N.; Prokshin, N.E.

    1995-01-01

    Treatment of spent decontamination solutions is the most complicated task in the whole problem of management of liquid radioactive waste, because quite often they have complex compositions, which makes it difficult to find for them effective and non-expensive treatment technology. New methods of treatment of such a waste is proposed based on use of specific sorption ability of ferro- and ferri-species in solution. These species are often present in solution as the by-products, and in combination with other components of decontamination solution they can be used as initial substances for synthesis of valuable sorbents directly in treating solution. Using specific compositions and conditions in solution, it is possible to make liquid waste treatment process more effective and less expensive. Particular examples of this process is presented in this work

  14. Extractive metallurgy. Recent advances

    International Nuclear Information System (INIS)

    Stevenson, E.J.

    1977-01-01

    Detailed technical information derived from patents issued since 1975 on extractive metallurgy is presented. In part one, concerning copper, the major areas covered are: smelting and roasting; acid leaching; ammonia leach processes; cuprous chloride and ferric chloride; and recovery of copper values from solution. Part two covers other metals, including: nickel and cobalt; ocean floor nodules; lead, zinc, molybdenum and manganese; precious metals; and uranium titanium, tantalum, rhenium, gallium, and other metals

  15. Metallurgy for nuclear engineering

    International Nuclear Information System (INIS)

    Kozlov, A.F.

    1986-01-01

    Principal ways of development in metallurgy and metallurgical equipment on nuclear engineering plants are discussed. A great attention is paid to changing welded structures for casted and forged ones. These measures give the possibility to increase reliability of NPP components and decrease labour content. The following processing procedures have been introduced: vacuum carbon reduction providing small amount of nonmetallic inclusions in reactor vessel steel; manufacturing steel large-size castings (360 and 420 t) for WWER vessels; rolling at plate mill 5000 etc

  16. Development of titanium based biocomposite by powder metallurgy processing with in situ forming of Ca-P phases

    Energy Technology Data Exchange (ETDEWEB)

    Karanjai, Malobika [International Advanced Research Centre for Powder Metallurgy and New Materials, Balapur P.O., Hyderabad 500005, Andhra Pradesh (India)]. E-mail: malobika@arci.res.in; Sundaresan, Ranganathan [International Advanced Research Centre for Powder Metallurgy and New Materials, Balapur P.O., Hyderabad 500005, Andhra Pradesh (India); Rao, Gummididala Venkata Narasimha [International Advanced Research Centre for Powder Metallurgy and New Materials, Balapur P.O., Hyderabad 500005, Andhra Pradesh (India); Mohan, Tallapragada Raja Rama [Metallurgical Engineering and Materials Science Department, Indian Institute of Technology, Powai, Mumbai 400076, Maharashtra (India); Kashyap, Bhagwati Prasad [Metallurgical Engineering and Materials Science Department, Indian Institute of Technology, Powai, Mumbai 400076, Maharashtra (India)

    2007-02-25

    Composites of titanium and calcium-phosphorus phases were developed by powder metallurgy processing and evaluated for bioactivity. Titanium hydride powder and precursors of calcium and phosphorus in the form of calcium carbonate and di-ammonium hydrogen orthophosphate were mixed in different proportions, compacted and calcined in different atmospheres. The calcined compacts were subsequently crushed, recompacted and sintered in vacuum. In situ formation of bioactive phases like hydroxylapatite, tricalcium phosphate and calcium titanate during the calcination and sintering steps was studied using X-ray diffraction. The effect of calcination atmosphere on density, interconnected porosity, phase composition and modulus of rupture of sintered composites was examined. The sintered composites were immersed in simulated body fluid for 7 days to observe their in vitro behaviour with XRD and FTIR spectroscopic identification of deposits. Composites with 10 wt% precursors sintered from vacuum calcined powder gave the best results in terms of bioactive phases, density and strength.

  17. Effect of processing of mechanical alloying and powder metallurgy on microstructure and properties of Cu-Al-Ni-Mn alloy

    International Nuclear Information System (INIS)

    Xiao Zhu; Li Zhou; Fang Mei; Xiong Shiyun; Sheng Xiaofei; Zhou Mengqi

    2008-01-01

    The fabrication conditions of Cu-Al-Ni-Mn alloy powder by mechanical alloying and powder metallurgy have been systematically studied. The mechanically alloyed powder (MAed powder) was fabricated at a speed between 100 rpm and 300 rpm for various milling times with and without process control agent (PCA). With an increasing of milling time, the size of crystallite grain decreases. Only the Cu diffraction pattern appear as the rotation speed is up to 300 rpm for 25 h. The elemental powders with PCA agglomerate slightly, but the degree of alloying is lower than that without PCA. The shape memory recovery of the quenched sample hot-extruded at extrusion rate of 50:1 is measured to be 100% recovered in 250 deg. C oil bath for 40 s after deformed to 4.0%. After aging at 120 deg. C for 10 days, the shape memory recovery of the alloy remains 98%

  18. Martensitic transformations, structure, and strengthness of processed high-nitrogen and high-carbon ferrous alloys

    Science.gov (United States)

    Kaputkina, L. M.; Prokoshkina, V. G.

    2003-10-01

    Structures and properties of metastable austenitic alloys Fe-18Cr-16Ni-I2Mn-(0.17 to 0. 50)N, Fe-18Cr-12Mn-(0.48 to 1.12)N, Fe-18Cr-(0.1 to 1.18)N, and Fe-(12 to 20)Ni-(0.6 to 1.3)C, Fe-(6 to 8)Mn-(0.6 to 1.0)C, Fe-(5 to 6)Cr-(4 to 5)Mn-(0.6 to 0.8)C, Fe-6Cr-(1.0 to 1.3)C resulting from martensitic transformations under cooling and cold deformation (CD), as well as following tempering processes, were studied by magnetometry, X-ray and electron microscopy analyses, hardness measurements and mechanical properties tests. Martensite with a b.c.t. lattice was formed in all alloys with M_s{>}-196^circC during cooling. Under CD transformations of γ{to}α, γ{to}\\varepsilon{to}α, or γ{to}\\varepsilon types were realized depending on the alloy composition. Carbon increased but nitrogen decreased stacking fault energy. Thus carbon assists α-martensite formation but nitrogen promotese. As CD level and/or concentration of carbon and nitrogen increase residual stresses resulting from the CD also increase. The martensitic transformation during CD can decrease the residual stresses. Kinetic of tempering of b.c.t. thermal martensite differs from those of CD-induced martensite. In the second case, deformation aging, texture, and residual stresses are more visible. The maximal strengthening under CD takes place in (Mn+N)-steels. (Cr+N) and (Cr+Mn+N)-steels are high-strength, non-magnetic and corrosion resistant and are easily hardened by a low level of plastic deformation.

  19. Nuclear energy in metallurgy

    Energy Technology Data Exchange (ETDEWEB)

    Jirak, Z; Malik, J; Vrba, J

    1976-01-01

    The present power situation and its estimated development with a view to metallurgy is presented. The possibilities of the development of Czechoslovak metallurgy are described with regard to conventional fuels and to nuclear power applications. The programme of the use of nuclear power in countries with a highly developed metallurgical industry, such as Japan, the FRG, etc., is presented and the technical pre-requisites for the use of nuclear power in metallurgy, namely the use of high temperature reactors and their incorporation in nuclear metallurgical complexes are discussed. The problems are indicated of the selection of suitable materials for high temperature reactors and the experience is described with the operation of such equipment. The results are given of the analysis of 10 variants of the model of a nuclear metallurgical complex manufacturing 1000 tons of sponge iron per day and having four main technological circuits (the helium circuit, the steam circuit, the reduction gas circuit and the cycle of metallurgical processes). An estimate is given of the capital costs of building a high temperature reactor, a power plant and a metallurgical complex with the reactor. The costs are also given of steel and power production in a nuclear metallurgical complex.

  20. The ferrous ammonium sulfate solid system, as dosemeter for processes at low temperatures and high doses of gamma radiation

    International Nuclear Information System (INIS)

    Juarez C, J.M.; Ramos B, S.; Negron M, A.

    2005-01-01

    This paper presents the results obtained from a study of the radiation induced oxidation of crystalline ferrous ammonium sulfate with gamma rays at 295 K, 263 K and 77 K and dose from 0 to 300 kGy. The radiation induced decomposition of ferrous ammonium sulfate has been studied by the dissolution of the irradiated salt in 0,8 N sulfuric acid. The main product is Fe 3+ and molar concentration of ferric ion was determined spectrophotometrically in the UV region at 304 nm. The optical density values showed a linear dependence with dose, indicating that the data obtained might be used to create a calibrating curve. Color in irradiated salt changes from blue to green, yellow and orange according to the absorbed dose. The accuracy and the reproducibility of the system were tested. In addition, some other characteristics make possible the use of this system as a dosimeter, similar to Fricke chemical dosemeter, at low temperatures and high dose. (Author)

  1. Effect of vanadium carbide on dry sliding wear behavior of powder metallurgy AISI M2 high speed steel processed by concentrated solar energy

    Energy Technology Data Exchange (ETDEWEB)

    García, C. [Materials Engineering. E.I.I., Universidad de Valladolid. C/Paseo del cauce 59, 47011 Valladolid (Spain); Romero, A. [E.T.S. Ingenieros Industriales. Instituto de Investigaciones Energéticas y Aplicaciones Industriales (INEI). Universidad de Castilla-La Mancha, Edificio Politécnico, Avda. Camilo José Cela s/n, 13071 Ciudad Real (Spain); Herranz, G., E-mail: gemma.herranz@uclm.es [E.T.S. Ingenieros Industriales. Instituto de Investigaciones Energéticas y Aplicaciones Industriales (INEI). Universidad de Castilla-La Mancha, Edificio Politécnico, Avda. Camilo José Cela s/n, 13071 Ciudad Real (Spain); Blanco, Y.; Martin, F. [Materials Engineering. E.I.I., Universidad de Valladolid. C/Paseo del cauce 59, 47011 Valladolid (Spain)

    2016-11-15

    Mixtures of AISI M2 high speed steel and vanadium carbide (3, 6 or 10 wt.%) were prepared by powder metallurgy and sintered by concentrated solar energy (CSE). Two different powerful solar furnaces were employed to sinter the parts and the results were compared with those obtained by conventional powder metallurgy using a tubular electric furnace. CSE allowed significant reduction of processing times and high heating rates. The wear resistance of compacts was studied by using rotating pin-on-disk and linearly reciprocating ball-on-flat methods. Wear mechanisms were investigated by means of scanning electron microscopy (SEM) observations and chemical inspections of the microstructures of the samples. Better wear properties than those obtained by conventional powder metallurgy were achieved. The refinement of the microstructure and the formation of carbonitrides were the reasons for this. - Highlights: •Powder metallurgy of mixtures of M2 high speed steel and VC are studied. •Some sintering is done by concentrated solar energy. •Rotating pin-on-disk and linearly reciprocating ball-on-flat methods are used. •The tribological properties and wear mechanisms, under dry sliding, are studied.

  2. The extractive metallurgy of gold

    Energy Technology Data Exchange (ETDEWEB)

    Kongolo, K.; Mwema, M.D. [University of Lubumbashi, Zaire, Gecamines Metallurgical Research Centre, Likasi, Zaire, c/o Gecamines Brussels (Belgium)

    1998-12-15

    Moessbauer spectroscopy has been successfully used in investigation of the gold compounds present in ores and the gold species which occur during the process metallurgy of this metal. This paper is a survey of the basic recovery methods and techniques used in extractive metallurgy of gold. Process fundamentals on mineral processing, ore leaching, zinc dust cementation, adsorption on activated carbon, electrowinning and refining are examined. The recovery of gold as a by-product of the copper industry is also described. Alternative processing methods are indicated in order to shed light on new interesting research topics where Moessbauer spectroscopy could be applied.

  3. The extractive metallurgy of gold

    Science.gov (United States)

    Kongolo, K.; Mwema, M. D.

    1998-12-01

    Mössbauer spectroscopy has been successfully used in investigation of the gold compounds present in ores and the gold species which occur during the process metallurgy of this metal. This paper is a survey of the basic recovery methods and techniques used in extractive metallurgy of gold. Process fundamentals on mineral processing, ore leaching, zinc dust cementation, adsorption on activated carbon, electrowinning and refining are examined. The recovery of gold as a by-product of the copper industry is also described. Alternative processing methods are indicated in order to shed light on new interesting research topics where Mössbauer spectroscopy could be applied.

  4. The extractive metallurgy of gold

    International Nuclear Information System (INIS)

    Kongolo, K.; Mwema, M.D.

    1998-01-01

    Moessbauer spectroscopy has been successfully used in investigation of the gold compounds present in ores and the gold species which occur during the process metallurgy of this metal. This paper is a survey of the basic recovery methods and techniques used in extractive metallurgy of gold. Process fundamentals on mineral processing, ore leaching, zinc dust cementation, adsorption on activated carbon, electrowinning and refining are examined. The recovery of gold as a by-product of the copper industry is also described. Alternative processing methods are indicated in order to shed light on new interesting research topics where Moessbauer spectroscopy could be applied

  5. Obtainment, machining and wear of metal matrix composites processed by powder metallurgy

    International Nuclear Information System (INIS)

    Jesus, Edilson Rosa Barbosa de.

    1998-01-01

    The aim of this investigation was the obtainment of metal matrix composites (MMC) by the route of powder metallurgy, and the valuation of these materials with relation to their machining and wear characteristics. Firstly, were obtained pure commercial aluminium matrix composites materials, with 5, 10 and 15% volumetric fraction of silicon carbide particles. Was also obtained a material without reinforcement particles in order to verify by comparison, the influence of addition of reinforcement particles. The obtained materials were characterized physics (hydrostatic density), mechanics (hardness and tensile tests) and microstructurally (optical microscopy and scanning electron microscopy). The results showed a homogeneous distribution of reinforcement particles in the composite, and improvement in the mechanical properties, mainly tensile strength (UTS) in comparison to the unreinforced material. After, tests were made to verify the materials behavior during machining and to check the performance of several tool materials (cemented carbide, ceramics and polycrystalline diamond). In these tests, values of the cutting force were measured by instrumented tool-holders. Phenomena such as tool wear, built-up edge formation and mechanism of chip formation were also observed and evaluated. The results from the cemented carbide tool tests, were utilised for the machinability index determination of each material. These results were applied to the Taylor equation and the equation constants for each material and test conditions were determined. The results showed that the inclusion of silicon carbide particles made extremely difficult the machining of the composites, and only with diamond tool, satisfactory results were obtained. At last, wear tests were performed to verify the influence of the reinforcement particles in the characteristics of wear resistance of the materials. The results obtained were utilized in the wear coefficient determination for each material. The

  6. Microstructures and mechanical responses of powder metallurgy non-combustive magnesium extruded alloy by rapid solidification process in mass production

    International Nuclear Information System (INIS)

    Kondoh, Katsuyoshi; Hamada, EL-Sayed Ayman; Imai, Hisashi; Umeda, Junko; Jones, Tyrone

    2010-01-01

    Spinning Water Atomization Process (SWAP), which was one of the rapid solidification processes, promised to produce coarse non-combustible magnesium alloy powder with 1-4 mm length, having fine α-Mg grains and Al 2 Ca intermetallic compounds. It had economical and safe benefits in producing coarse Mg alloy powders with very fine microstructures in the mass production process due to its extreme high solidification rate compared to the conventional atomization process. AMX602 (Mg-6%Al-0.5%Mn-2%Ca) powders were compacted at room temperature. Their green compacts with a relative density of about 85% were heated at 573-673 K for 300 s in Ar gas atmosphere, and immediately consolidated by hot extrusion. Microstructure observation and evaluation of mechanical properties of the extruded AMX602 alloys were carried out. The uniform and fine microstructures with grains less than 0.45-0.8 μm via dynamic recrystallization during hot extrusion were observed, and were much small compared to the extruded AMX602 alloy fabricated by using cast ingot. The extremely fine intermetallic compounds 200-500 nm diameter were uniformly distributed in the matrix of powder metallurgy (P/M) extruded alloys. These microstructures caused excellent mechanical properties of the wrought alloys. For example, in the case of AMX602 alloys extruded at 573 K, the tensile strength (TS) of 447 MPa, yield stress (YS) of 425 MPa and 9.6% elongation were obtained.

  7. Thermal stability and creep behaviour of MgNiYCe-rich mischmetal alloys processed by a powder metallurgy route

    Czech Academy of Sciences Publication Activity Database

    Peréz, P.; Milička, Karel; Badia, J. M.; Garcés, G.; Antoranz, J. M.; Gonzáles, S.; Dobeš, Ferdinand; Adeva, P.

    289-292, - (2009), s. 127-136 ISSN 1012-0386. [DIMAT 2008, International Conference on Diffusion in Materials /7./. Lanzarote, Canary Islands, 28.10.2008-31.10.2008] Grant - others:Ministerio de Ciencia y Tecnologia (ES) MAT2006-11731-C02 Institutional research plan: CEZ:AV0Z20410507 Keywords : magnesium alloys * powder metallurgy * microstructure * thermal stability * creep Subject RIV: JG - Metallurgy

  8. Neutron radiography in metallurgy

    International Nuclear Information System (INIS)

    Rant, J.; Ilic, R.

    1977-01-01

    The review surveys microneutronographic and neutron-induced autoradiographic techniques and their applications in metallurgy. A brief survey of applications of neutron radiography as a method of non-destructive testing to some macroscopic problems in metallurgy is included. (author)

  9. Molybdeno-Aluminizing of Powder Metallurgy and Wrought Ti and Ti-6Al-4V alloys by Pack Cementation process

    International Nuclear Information System (INIS)

    Tsipas, Sophia A.; Gordo, Elena

    2016-01-01

    Wear and high temperature oxidation resistance of some titanium-based alloys needs to be enhanced, and this can be effectively accomplished by surface treatment. Molybdenizing is a surface treatment where molybdenum is introduced into the surface of titanium alloys causing the formation of wear-resistant surface layers containing molybdenum, while aluminizing of titanium-based alloys has been reported to improve their high temperature oxidation properties. Whereas pack cementation and other surface modification methods have been used for molybdenizing or aluminizing of wrought and/or cast pure titanium and titanium alloys, such surface treatments have not been reported on titanium alloys produced by powder metallurgy (PM). Also a critical understanding of the process parameters for simultaneous one step molybdeno-aluminizing of titanium alloys by pack cementation and the predominant mechanism for this process have not been reported. The current research work describes the surface modification of titanium and Ti-6Al-4V prepared by PM by molybdeno-aluminizing and analyzes thermodynamic aspects of the deposition process. Similar coatings are also deposited to wrought Ti-6Al-4V and compared. Characterization of the coatings was carried out using scanning electron microscopy and x-ray diffraction. For both titanium and Ti-6Al-4V, the use of a powder pack containing ammonium chloride as activator leads to the deposition of molybdenum and aluminium into the surface but also introduces nitrogen causing the formation of a thin titanium nitride layer. In addition, various titanium aluminides and mixed titanium aluminium nitrides are formed. The appropriate conditions for molybdeno-aluminizing as well as the phases expected to be formed were successfully determined by thermodynamic equilibrium calculations. - Highlights: •Simultaneous co-deposition of Mo-Al onto powder metallurgy and wrought Ti alloy •Thermodynamic calculations were used to optimize deposition conditions

  10. Molybdeno-Aluminizing of Powder Metallurgy and Wrought Ti and Ti-6Al-4V alloys by Pack Cementation process

    Energy Technology Data Exchange (ETDEWEB)

    Tsipas, Sophia A., E-mail: stsipas@ing.uc3m.es; Gordo, Elena

    2016-08-15

    Wear and high temperature oxidation resistance of some titanium-based alloys needs to be enhanced, and this can be effectively accomplished by surface treatment. Molybdenizing is a surface treatment where molybdenum is introduced into the surface of titanium alloys causing the formation of wear-resistant surface layers containing molybdenum, while aluminizing of titanium-based alloys has been reported to improve their high temperature oxidation properties. Whereas pack cementation and other surface modification methods have been used for molybdenizing or aluminizing of wrought and/or cast pure titanium and titanium alloys, such surface treatments have not been reported on titanium alloys produced by powder metallurgy (PM). Also a critical understanding of the process parameters for simultaneous one step molybdeno-aluminizing of titanium alloys by pack cementation and the predominant mechanism for this process have not been reported. The current research work describes the surface modification of titanium and Ti-6Al-4V prepared by PM by molybdeno-aluminizing and analyzes thermodynamic aspects of the deposition process. Similar coatings are also deposited to wrought Ti-6Al-4V and compared. Characterization of the coatings was carried out using scanning electron microscopy and x-ray diffraction. For both titanium and Ti-6Al-4V, the use of a powder pack containing ammonium chloride as activator leads to the deposition of molybdenum and aluminium into the surface but also introduces nitrogen causing the formation of a thin titanium nitride layer. In addition, various titanium aluminides and mixed titanium aluminium nitrides are formed. The appropriate conditions for molybdeno-aluminizing as well as the phases expected to be formed were successfully determined by thermodynamic equilibrium calculations. - Highlights: •Simultaneous co-deposition of Mo-Al onto powder metallurgy and wrought Ti alloy •Thermodynamic calculations were used to optimize deposition conditions

  11. Histomorphologic evaluation of Ti-13Nb-13Zr alloys processed via powder metallurgy. A study in rabbits

    International Nuclear Information System (INIS)

    Bottino, M.C.; Coelho, P.G.; Yoshimoto, M.; Koenig, B.; Henriques, V.A.R.; Bressiani, A.H.A.; Bressiani, J.C.

    2008-01-01

    This study presents the in-vivo evaluation of Ti-13Nb-13Zr alloy implants obtained by the hydride route via powder metallurgy. The cylindrical implants were processed at different sintering and holding times. The implants' were characterized for density, microstructure (SEM), crystalline phases (XRD), and bulk (EDS) and surface composition (XPS). The implants were then sterilized and surgically placed in the central region of the rabbit's tibiae. Two double fluorescent markers were applied at 2 and 3 weeks, and 6 and 7 weeks after implantation. After an 8-week healing period, the implants were retrieved, non-decalcified section processed, and evaluated by electron, UV light (fluorescent labeling), and light microscopy (toluidine blue). BSE-SEM showed close contact between bone and implants. Fluorescent labeling assessment showed high bone activity levels at regions close to the implant surface. Toluidine blue staining revealed regions comprising osteoblasts at regions of newly forming/formed bone close to the implant surface. The results obtained in this study support biocompatible and osseoconductive properties of Ti-13Nb-13Zr processed through the hydride powder route

  12. Histomorphologic evaluation of Ti-13Nb-13Zr alloys processed via powder metallurgy. A study in rabbits

    Energy Technology Data Exchange (ETDEWEB)

    Bottino, M.C. [Department of Materials Science and Engineering, University of Alabama at Birmingham, BEC 254 1530 3rd Avenue South, Birmingham, AL, 35294 (United States); Coelho, P.G. [Department of Biomaterials and Biomimetics, New York University, College of Dentistry, 345 East 24th Street, Room 804S, New York, NY, 10100 (United States)], E-mail: pgcoelho@nyu.edu; Yoshimoto, M. [Materials Science and Technology Center, Institute for Energy and Nuclear Research, Av. Prof. Lineu Prestes, 2242, Sao Paulo, SP, 05508-000 (Brazil); Koenig, B. [Department of Anatomy, Institute of Biomedical Sciences, University of Sao Paulo (ICB-USP) Av. Prof. Lineu Prestes, 2415, Sao Paulo, SP, 05508-900 (Brazil); Henriques, V.A.R. [Materials Division (AMR/IAE), CTA Brazilian Aerospace Technical Center, Sao Jose dos Campos, SP, 12228-904 (Brazil); Bressiani, A.H.A.; Bressiani, J.C. [Materials Science and Technology Center, Institute for Energy and Nuclear Research, Av. Prof. Lineu Prestes, 2242, Sao Paulo, SP, 05508-000 (Brazil)

    2008-03-10

    This study presents the in-vivo evaluation of Ti-13Nb-13Zr alloy implants obtained by the hydride route via powder metallurgy. The cylindrical implants were processed at different sintering and holding times. The implants' were characterized for density, microstructure (SEM), crystalline phases (XRD), and bulk (EDS) and surface composition (XPS). The implants were then sterilized and surgically placed in the central region of the rabbit's tibiae. Two double fluorescent markers were applied at 2 and 3 weeks, and 6 and 7 weeks after implantation. After an 8-week healing period, the implants were retrieved, non-decalcified section processed, and evaluated by electron, UV light (fluorescent labeling), and light microscopy (toluidine blue). BSE-SEM showed close contact between bone and implants. Fluorescent labeling assessment showed high bone activity levels at regions close to the implant surface. Toluidine blue staining revealed regions comprising osteoblasts at regions of newly forming/formed bone close to the implant surface. The results obtained in this study support biocompatible and osseoconductive properties of Ti-13Nb-13Zr processed through the hydride powder route.

  13. Influences of Processing and Fatigue Cycling on Residual Stresses in a NiCrY-Coated Powder Metallurgy Disk Superalloy

    Science.gov (United States)

    Gabb, T. P.; Rogers, R. B.; Nesbitt, J. A.; Miller, R. A.; Puleo, B. J.; Johnson, D.; Telesman, J.; Draper, S. L.; Locci, I. E.

    2017-11-01

    Oxidation and corrosion can attack superalloy disk surfaces exposed to increasing operating temperatures in some turbine engine environments. Any potential protective coatings must also be resistant to harmful fatigue cracking during service. The objective of this study was to investigate how residual stresses evolve in one such coating. Fatigue specimens of a powder metallurgy-processed disk superalloy were coated with a NiCrY coating, shot peened, and then subjected to fatigue in air at room and high temperatures. The effects of this processing and fatigue cycling on axial residual stresses and other aspects of the coating were assessed. While shot peening did induce beneficial compressive residual stresses in the coating and substrate, these stresses relaxed in the coating with subsequent heating. Several cast alloys having compositions near the coating were subjected to thermal expansion and tensile stress relaxation tests to help explain this response of residual stresses in the coating. For the coated fatigue specimens, this response contributed to earlier cracking of the coating than for the uncoated surface during long intervals of cycling at 760 °C. Yet, substantial compressive residual stresses still remained in the substrate adjacent to the coating, which were sufficient to suppress fatigue cracking there. The coating continued to protect the substrate from hot corrosion pitting, even after fatigue cracks initiated in the coating.

  14. In the coking section of the Scientific Council of the Main Committee for Science and Technology 'New processes in ferrous metallurgy'

    Energy Technology Data Exchange (ETDEWEB)

    Bukvareva, O.F.

    1989-12-01

    Reports on a meeting held in June 1990 in Khar'kov on new technologies of black coal coking and methods for coal gas purification used in the USSR and other countries. The following problems associated with economic analysis of new coking technologies were analyzed: types of coal used in mixtures for coking, mixtures for coking, coal mixture preheating, partial briquetting. The following problems associated with coal gas purification were discussed: primary cooling systems, methods for ammonia separation from coal gas, coal gas desulfurization, separation of hydrogen cyanide, amine methods for desulfurization. Recommendations for research programs on new coking technologies and on coal gas purification are discussed.

  15. Mechanical properties of AZ31 alloy processed by a green metallurgy route; Propiedades mecanicas de la aleacion AZ31 procesada por una ruta eco-sostenible

    Energy Technology Data Exchange (ETDEWEB)

    D' Enrico, F.; Garces, G.; Hofer, M.; Kim, S. K.; Perez, P.; Cabeza, S.; Adeva, P.

    2013-07-01

    Recently it has been proved that molding of defect-free components of various commercial alloys of magnesium can be carried out successfully when small amounts of CaO are added to the melt, making unnecessary the use of SF{sub 6} coverage. In the case of AZ alloys, this process also remarkably improves their mechanical properties not only by the greater cleaning of alloys but also by the formation of CaAl{sub 2} phase. This work, part of the Green project Metallurgy (http://www.green-metallurgy.eu) funded by the European Union (LIFE+2009), studies the influence of different CaO additions on the microstructure and mechanical properties of AZ31 Eco-Mg alloy. The alloy was processed by a conventional route involving extrusion of as-cast rods as well as by a powder metallurgy route (PM) using chips as starting material. The objective was to analyze the viability of recycling machining chips to manufacture components for the automobile industry and transportation in general, because of its low cost and environmental impact. It has been demonstrated that alloys processed from chips exhibit the highest tensile stress values, close to 320 MPa. (Author)

  16. Effect of the Machining Processes on Low Cycle Fatigue Behavior of a Powder Metallurgy Disk

    Science.gov (United States)

    Telesman, J.; Kantzos, P.; Gabb, T. P.; Ghosn, L. J.

    2010-01-01

    A study has been performed to investigate the effect of various machining processes on fatigue life of configured low cycle fatigue specimens machined out of a NASA developed LSHR P/M nickel based disk alloy. Two types of configured specimen geometries were employed in the study. To evaluate a broach machining processes a double notch geometry was used with both notches machined using broach tooling. EDM machined notched specimens of the same configuration were tested for comparison purposes. Honing finishing process was evaluated by using a center hole specimen geometry. Comparison testing was again done using EDM machined specimens of the same geometry. The effect of these machining processes on the resulting surface roughness, residual stress distribution and microstructural damage were characterized and used in attempt to explain the low cycle fatigue results.

  17. Extractive metallurgy of the beryllium

    International Nuclear Information System (INIS)

    Alonso, Neusa; Capocchi, Jose Deodoro Trani

    1995-01-01

    A bibliographic review is performed on the beryllium extractive metallurgy. The work describes the main type of ores and processes applied to the metallic beryllium production, beryllium oxide production using fluoride, sulfide and direct chlorination. The thermodynamic consideration are made on beryllium reduction processes, discussing the viability of the beryllium oxide and hallide reduction processes. Under the technological viewpoint, the Cu-Be alloys main production processes are discussed, and the main toxicity problems related with beryllium are mentioned

  18. Radiation technologies in metallurgy and machinery

    International Nuclear Information System (INIS)

    Meshkov, I.N.

    1990-01-01

    Applications of electron beam accelerators for technologies in metallurgy and machinery are discussed. Processes described are provided with special industrial accelerators, developed in the Institute of Nuclear Physics, Novosibirsk. (author)

  19. Radiotracer investigations of the shaft processes in Polish zinc and lead metallurgy. 2

    International Nuclear Information System (INIS)

    Michalik, J.S.; Bazaniak, Z.; Palige, J.

    1990-01-01

    The conditions and the physico-chemical processes occurring in the ISP furnace cause the possibility of partial reoxidation of vapourized zinc escaping from the furnace counter-current to the batch material. In order to determine the reoxidation degree and localize the active zone the radiotracer method was applied. The method of solving the convolution integral was used. The experimental part resulted indetermination of impulse characteristics of the zinc condenser; in the next step, the curves of zinc concentration distribution at the ISP furnace outlet were found by calculations. 65 Zn was used as tracer for the industrial experiments. About 25-30% of total amount of zinc obtained as a result of zinc oxides reduction processes undergoes reoxidation in the surface layer of the bath in the furnace shaft. The method of tracer preparation for investigating the behaviour of zinc occurring in the form of silicates and ferrates in the shaft has been proposed. (author)

  20. Processing and physical metallurgy of NdFeB and other R.E. magnets

    International Nuclear Information System (INIS)

    Ormerod, J.

    1985-01-01

    The background to the developmetn of NdFeB-based permanent magnets is described. The processing of NdFeB permanent magnets is outlined and compared with the production of SmCo-based permanent magnets. Some metallographic observations of sintered NdFeB magnets are presented. Finally, the improvement and future development of NdFeB and related permanent magnet materials are discussed

  1. Low-temperature synthesis of MgB{sub 2} via powder metallurgy processing

    Energy Technology Data Exchange (ETDEWEB)

    Birol, Yucel [Dokuz Eylul University, Department of Metallurgical and Materials Engineering, Faculty of Engineering, Buca, Izmir (Turkey)

    2016-12-15

    Ball-milled Mg/B{sub 2}O{sub 3} powder blends reveal interpenetrating layers of deformed magnesium and boron oxide grains that are increasingly refined with increasing milling time. Boron oxide is reduced by Mg and MgO thus formed reacts with the remaining B{sub 2}O{sub 3} to produce Mg{sub 3}(BO{sub 3}){sub 2} during ball milling for 30 min. Both B{sub 2}O{sub 3} and Mg{sub 3}(BO{sub 3}){sub 2} react with Mg to produce MgB{sub 2} upon further ball milling. An annealing treatment can be employed when ball milling is performed for less than 1 h as thermal exposure of the ball-milled Mg/B{sub 2}O{sub 3} powder blends also leads to the formation of MgB{sub 2}. The above reactions take place between 500 and 700 C when the Mg/B{sub 2}O{sub 3} powder blend is ball milled for 30 min, and between 450 and 550 C, after ball milling for 1 h. This is a very attractive route owing to processing temperatures where the volatility of Mg is no longer a problem. (orig.)

  2. Optimization of the Hot Forging Processing Parameters for Powder Metallurgy Fe-Cu-C Connecting Rods Based on Finite Element Simulation

    Science.gov (United States)

    Li, Fengxian; Yi, Jianhong; Eckert, Jürgen

    2017-12-01

    Powder forged connecting rods have the problem of non-uniform density distributions because of their complex geometric shape. The densification behaviors of powder metallurgy (PM) connecting rod preforms during hot forging processes play a significant role in optimizing the connecting rod quality. The deformation behaviors of a connecting rod preform, a Fe-3Cu-0.5C (wt pct) alloy compacted and sintered by the powder metallurgy route (PM Fe-Cu-C), were investigated using the finite element method, while damage and friction behaviors of the material were considered in the complicated forging process. The calculated results agree well with the experimental results. The relationship between the processing parameters of hot forging and the relative density of the connecting rod was revealed. The results showed that the relative density of the hot forged connecting rod at the central shank changed significantly compared with the relative density at the big end and at the small end. Moreover, the relative density of the connecting rod was sensitive to the processing parameters such as the forging velocity and the initial density of the preform. The optimum forging processing parameters were determined and presented by using an orthogonal design method. This work suggests that the processing parameters can be optimized to prepare a connecting rod with uniform density distribution and can help to better meet the requirements of the connecting rod industry.

  3. New evidence for prehistoric copper metallurgy in the vicinity of Bor

    Directory of Open Access Journals (Sweden)

    Kapuran Aleksandar

    2016-01-01

    Full Text Available The last three years of archaeological investigations at the site Ru`ana in Banjsko Polje, in the immediate vicinity of Bor, have provided new evidence regarding the role of non-ferrous metallurgy in the economy of the prehistoric communities of north-eastern Serbia. The remains of metallurgical furnaces and a large amount of metallic slags at two neighbouring sites in the mentioned settlement reveal that locations with many installations for the thermal processing of copper ore existed in the Bronze Age. We believe, judging by the finds of material culture, that metallurgical activities in this area also continued into the Iron Age and, possibly, into the 4th century AD. [Projekat Ministarstva nauke Republike Srbije, br. 177020: Archaeology of Serbia: Cultural identity, integration factors, technological processes and the role of the central Balkans in the development of European prehistory

  4. Advanced powder metallurgy aluminum alloys and composites

    Science.gov (United States)

    Lisagor, W. B.; Stein, B. A.

    1982-01-01

    The differences between powder and ingot metallurgy processing of aluminum alloys are outlined. The potential payoff in the use of advanced powder metallurgy (PM) aluminum alloys in future transport aircraft is indicated. The national program to bring this technology to commercial fruition and the NASA Langley Research Center role in this program are briefly outlined. Some initial results of research in 2000-series PM alloys and composites that highlight the property improvements possible are given.

  5. Densification of powder metallurgy billets by a roll consolidation technique

    Science.gov (United States)

    Sellman, W. H.; Weinberger, W. R.

    1973-01-01

    Container design is used to convert partially densified powder metallurgy compacts into fully densified slabs in one processing step. Technique improves product yield, lowers costs and yields great flexibility in process scale-up. Technique is applicable to all types of fabricable metallic materials that are produced from powder metallurgy process.

  6. A facile route to modify ferrous phosphate and its use as an iron-containing resource for LiFePO4 via a polyol process.

    Science.gov (United States)

    Li, Shaomin; Liu, Xichuan; Mi, Rui; Liu, Hao; Li, Yinchuan; Lau, Woon-min; Mei, Jun

    2014-06-25

    This study introduces an economical and environmentally friendly way of synthesizing LiFePO4/C to be used as cathode material in lithium ion batteries via two processes: (1) the synthesis of LiFePO4/C cathode material using a low cost divalent precursor ferrous phosphate, Fe3 (PO4)2·8H2O, as iron source in a polyol process and (2) the modification of the morphology of this precursor by varying the reaction time in a coprecipitation process. The study examines the effects of different structures and morphologies of the precursor on the structure and electrochemical performance of the as-synthesized LiFePO4/C. The LiFePO4/C shows an excellent rate capability and cycle performance, with initial discharge capacities of 153, 128, and 106 mA h g(-1) at 1 C, 5 C, and 10 C. The capacity retention is respectively 98.7%, 98.2%, and 98.7%, after 10 cycles at the corresponding rates. The capacity retention remains at 97% even after 300 cycles at the rate of 10 C. The outstanding electrochemical performance can be attributed to the improved rate of Li(+) diffusion and the excellent crystallinity of synthesized LiFePO4/C powders through the modified precursor. Therefore, this is an economical and environmentally friendly way of synthesizing LiFePO4/C to be used as cathode material in lithium ion batteries.

  7. NON-FERROUS EXPORTS CONCENTRATION AND GLOBAL INVESTMENTS

    Directory of Open Access Journals (Sweden)

    Brîndușa COVACI

    2016-12-01

    Full Text Available In the context of high-tech and telecommunication, non-ferrous sector has a crucial role in industries development. Cooper, nickel, aluminum, zinc, lead and tin are used, directly or indirectly, in most of the technologies, especially in high-tech production. The paper present a short index of the global investments for the non-ferrous transnational corporations listed on London Metal Exchange. The non-ferrous investment index presented in the paper refers to the most profitable corporation exports on world, European Union (EU28 and Central and Eastern Europe (CEE level. The export concentration, estimated through Herfindahl-Hirschmann index on world, EU28, CEE and Romanian level, show that the non-ferrous industry is in full process of releasing. The cases presented in the article show that the non-ferrous companies invest intensively in equipment and technologies with superior production capacities, which combat pollution given by non-ferrous processes, research and development for the non-ferrous innovative technologies, and creating new markets. Sustainable and intelligent development is the inflexion point of the non-ferrous transnational corporation investments. The research is predominant in exploration of the transnational corporations’ internet pages and reports, and statistical calculus from international trade websites.

  8. Fundamentals of powder metallurgy

    International Nuclear Information System (INIS)

    Khan, I.H.; Qureshi, K.A.; Minhas, J.I.

    1988-01-01

    This book is being presented to introduce the fundamentals of technology of powder metallurgy. An attempt has been made to present an overall view of powder metallurgy technology in the first chapter, whereas chapter 2 to 8 deal with the production of metal powders. The basic commercial methods of powder production are briefly described with illustrations. Chapter 9 to 12 describes briefly metal powder characteristics and principles of testing, mixing, blending, conditioning, compaction and sintering. (orig./A.B.)

  9. Production of a low young modulus titanium alloy by powder metallurgy

    Directory of Open Access Journals (Sweden)

    Dalcy Roberto dos Santos

    2005-12-01

    Full Text Available Titanium alloys have several advantages over ferrous and non-ferrous metallic materials, such as high strengthto-weight ratio and excellent corrosion resistance. A blended elemental titanium powder metallurgy process has been developed to offer low cost commercial products. The process employs hydride-dehydride (HDH powders as raw material. In this work, results of the Ti-35Nb alloy sintering are presented. This alloy due to its lower modulus of elasticity and high biocompatibility is a promising candidate for aerospace and medical use. Samples were produced by mixing of initial metallic powders followed by uniaxial and cold isostatic pressing with subsequent densification by isochronal sintering between 900 up to 1600 °C, in vacuum. Sintering behavior was studied by means of microscopy and density. Sintered samples were characterized for phase composition, microstructure and microhardness by X-ray diffraction, scanning electron microscopy and Vickers indentation, respectively. Samples sintered at high temperatures display a fine plate-like alpha structure and intergranular beta. A few remaining pores are still found and density above 90% for specimens sintered in temperatures over 1500 °C is reached.

  10. Consolidation processing parameters and alternative processing methods for powder metallurgy Al-Cu-Mg-X-X alloys

    Science.gov (United States)

    Sankaran, K. K.

    1987-01-01

    The effects of varying the vacuum degassing parameters on the microstructure and properties of Al-4Cu-1Mg-X-X (X-X = 1.5Li-0.2Zr or 1.5Fe-0.75Ce) alloys processed from either prealloyed (PA) or mechanically alloyed (M) powder, and consolidated by either using sealed aluminum containers or containerless vacuum hot pressing were studied. The consolidated billets were hot extruded to evaluate microstructure and properties. The MA Li-containing alloy did not include Zr, and the MA Fe- and Ce-containing alloy was made from both elemental and partially prealloyed powder. The alloys were vacuum degassed both above and below the solution heat treatment temperature. While vacuum degassing lowered the hydrogen content of these alloys, the range over which the vacuum degassing parameters were varied was not large enough to cause significant changes in degassing efficiency, and the observed variations in the mechanical properties of the heat treated alloys were attributed to varying contributions to strengthening by the sub-structure and the dispersoids. Mechanical alloying increased the strength over that of alloys of similar composition made from PA powder. The inferior properties in the transverse orientation, especially in the Li-containing alloys, suggested deficiencies in degassing. Among all of the alloys processed for this study, the Fe- and Ce-containing alloys made from MA powder possessed better combinations of strength and toughness.

  11. Tungsten and tungsten alloys by powder metallurgy

    International Nuclear Information System (INIS)

    Belhadjhamida, A.; German, R.M.

    1991-01-01

    Tungsten has a historical link with powder metallurgy and there is continued progress in expanding the available compositions and processing options. This paper starts with an introduction to the history of tungsten powder metallurgy and use this as a basis for analyzing some of the current trends. The literature base in tungsten processing is expanding and includes new alloys, microstructures, and processing routes. A few examples will be emphasize here to produce a frame work for this program, including description of sintering mechanisms for tungsten, liquid phase sintering advances, hot consolidation fundamentals, and options for complex shaping using powder injection modeling. For this base, subsequent presentations will expand on these fundamental advances

  12. Data on processing of Ti-25Nb-25Zr β-titanium alloys via powder metallurgy route: Methodology, microstructure and mechanical properties.

    Science.gov (United States)

    Ueda, D; Dirras, G; Hocini, A; Tingaud, D; Ameyama, K; Langlois, P; Vrel, D; Trzaska, Z

    2018-04-01

    The data presented in this article are related to the research article entitled "Cyclic Shear behavior of conventional and harmonic structure-designed Ti-25Nb-25Zr β-titanium alloy: Back-stress hardening and twinning inhibition" (Dirras et al., 2017) [1]. The datasheet describes the methods used to fabricate two β-titanium alloys having conventional microstructure and so-called harmonic structure (HS) design via a powder metallurgy route, namely the spark plasma sintering (SPS) route. The data show the as-processed unconsolidated powder microstructures as well as the post-SPS ones. The data illustrate the mechanical response under cyclic shear loading of consolidated alloy specimens. The data show how electron back scattering diffraction(EBSD) method is used to clearly identify induced deformation features in the case of the conventional alloy.

  13. Preparation of nitinol by non-conventional powder metallurgy techniques

    Czech Academy of Sciences Publication Activity Database

    Novák, P.; Moravec, H.; Salvetr, P.; Průša, F.; Drahokoupil, Jan; Kopeček, Jaromír; Karlík, M.; Kubatík, Tomáš František

    2015-01-01

    Roč. 31, č. 15 (2015), s. 1886-1893 ISSN 0267-0836 R&D Projects: GA ČR(CZ) GA14-03044S Institutional support: RVO:68378271 ; RVO:61389021 Keywords : shape memory alloys * SHS process * SEM * powder metallurgy Subject RIV: JG - Metallurgy Impact factor: 1.008, year: 2015

  14. Study of the microstructural and mechanical properties of titanium-niobium-zirconium based alloys processed with hydrogen and powder metallurgy for use in dental implants

    International Nuclear Information System (INIS)

    Duvaizem, Jose Helio

    2009-01-01

    Hydrogen has been used as pulverization agent in alloys based on rare earth and transition metals due to its extremely high diffusion rate even on low temperatures. Such materials are used on hydrogen storage dispositives, generation of electricity or magnetic fields, and are produced by a process which the first step is the transformation of the alloy in fine powder by miling. Besides those, hydrogenium is also being used to obtain alloys based on titanium - niobium - zirconium in the pulverization. Powder metallurgy is utilized on the production of these alloys, making it possible to obtain structures with porous surface as result, requirement for its application as biomaterials. Other advantages of powder metallurgy usage include better surface finish and better microstructural homogeneity. In this work samples were prepared in the Ti-13Nb-13Zr composition. The hydrogenation was performed at 700 degree C, 600 degree C, and 500 degree C for titanium, niobium and zirconium respectively. After hydrogenation, the milling stage was carried out on high energy planetary ball milling with 200rpm during 90 minutes, and also in conventional ball milling for 30 hours. Samples were pressed in uniaxial press, followed by isostatic cold press, and then sintered at 1150 degree C for 7-13 hours. Microstructural properties of the samples were characterized by scanning electron microscope (SEM), energy dispersive spectroscopy (EDS) and x-ray diffraction. Mechanical and structural properties determined were density, microhardness and moduli of elasticity. The sample sintered at 1150 degree C for 7h, hydrogenated using 10.000 mbar and produced by milling on high energy planetary ball milling presented the best mechanical properties and microstructural homogeneity. (author)

  15. Industrial applications and metallurgy

    International Nuclear Information System (INIS)

    Torres M, N.; Melendrez C, G.; Morales, F.L.

    1989-01-01

    From 1961 the use of nuclear energy in the industrial field in Colombia has a big advance. Today nuclear isotopes are used by private companies in this kind of application the Area of Industrial Applications and Metallurgy was the institution section that has trained and has transferred the technology needed for this purpose

  16. Metallurgy Department publications 1988

    International Nuclear Information System (INIS)

    Schroeder Pedersen, A.; Bilde-Soerensen, J.B.

    1989-08-01

    A presentation (including abstracts) of scientific and technical publications and lectures by the staff of the Metallurgy Department during 1988 is given. The list comprises journal papers, conference papers, reports, lectures and poster presentations in the following catagories: Publications, Lectures and Poster Presentations. (author)

  17. Metallurgy Department publications 1989

    International Nuclear Information System (INIS)

    Horsewell, A.

    1990-08-01

    All publiclations by the staff of the Metallurgy Department during 1989 are listed. This list is divided into three sections as follows: Publications (journal and conference papers, reports); Lectures (public lecture presentations) and Posters (poster presentations at conferences and symposia). Abstracts are included. (author)

  18. ITRA 084 - a microprocessor controlled rapid analyzer in mining and metallurgy

    International Nuclear Information System (INIS)

    Kliem, V.; Kreher, M.; Boy, N.

    1986-01-01

    A new rapid analyzer of the ITRA series has been developed at the Freiberg Research Institute of Non-Ferrous Metals for single and multi-element analysis in mining and non-ferrous metallurgy. INTRA-08 represents an efficient microprocessor-controlled on-line X-ray fluorescence analyzer based on the main principles utilized with success hitherto in device engineering (isotope excitation, four-channel modification, balance filter method). A U880 single-chip microcomputer provides the central control of the device including the execution of an extensive program for the matrix correction. The efficiency of the analyzer is demonstrated taking measured values as a basis

  19. Modern electrochemical processes and technologies in ionic melts

    Directory of Open Access Journals (Sweden)

    Omelchuk A.

    2003-01-01

    Full Text Available An analysis of the known methods for the electrochemical purification of non-ferrous metals in ionic melts is presented. A comparative estimation of the results of the electrochemical purification of non-ferrous metals by different methods has been performed. The main regularities of the electrochemical behavior of non-ferrous metals in conventional and electrode micro-spacing electrolysis are presented. It has been found that when electrolyzing some metals, e. g. bismuth, gallium, there is either no mass exchange between the electrodes, or it occurs under filtration conditions. It has been shown that the electrode micro-spacing processes provide a high quality of non-ferrous metals purification at low specific consumption of electric power and reagents. The use of bipolar electrodes and β-alumina diaphragms hinders the transfer of metallic impurities from the anode to the cathode. The effects revealed were used to develop new processes for the separation of non-ferrous metal alloys in ionic melts; most of them have been put into practice in non-ferrous metallurgy.

  20. New processes in iron metallurgy discussed by the Coking Section of the Scientific Council of the Main Committee of Science and Technology of the USSR

    Energy Technology Data Exchange (ETDEWEB)

    Bukvareva, O.F.

    1991-02-01

    Discusses problems evaluated in October 1990 by the Section during the meeting devoted to research programs in the twelfth five-year plan, research and development of continuous coking methods, prospects for new coke quenching processes. Selected research programs, coordinated research programs and development programs as well as recommendations for future research programs are evaluated. The following research programs aimed at use of weakly caking and noncaking coals in the coking plants are evaluated: coal preheating and charging preheated mixtures to coke ovens, partial coal charge briquetting and equipment for coal briquetting, development of commercial systems for packing coal charges in coke ovens, production of formed coke for metallurgy, processes for coal gas cleaning (especially ammonia separation), development of systems for utilization of waste heat from dry coke quenching for coal charge preheating. Participation of individual research institutes in the programs is discussed. The most significant projects of individual institutes are discussed. Recommendations for research programs for the period 1991 to 1995 are made.

  1. Electron microscopy in metallurgy

    International Nuclear Information System (INIS)

    Loretto, M.H.

    1980-01-01

    The aim of this paper is to review briefly the contribution which (TEM) transmission electron microscopy (including high voltage electron microscopy (HVEM)) has made to metallurgy. Since it is straightforward with modern electron microscopes to extract the crystallographic information which provides the basis for any interpretation, the major problem in most metallurgical work lies in assessing how the structure (which TEM has characterised) has arisen and which properties of the specimen can be understood in terms of this structure. Radiation damage, quenching, phase transformations, grain boundaries and plastic deformation have been the main fields in which TEM has contributed significantly. After briefly summarising the role of TEM in each field, examples of recent work will be used to indicate current TEM activity in physical metallurgy. (author)

  2. Processing of W-Cu functionally graded materials (FGM) through the powder metallurgy route: application as plasma facing components for ITER-like thermonuclear fusion reactor

    International Nuclear Information System (INIS)

    Raharijaona, J.J.

    2009-11-01

    The aim of this study was to study and optimize the sintering of W-Cu graded composition materials, for first wall of ITER-like thermonuclear reactor application. The graded composition in the material generates graded functional properties (Functionally Graded Materials - FGM). Rough thermomechanical calculations have shown the interest of W-Cu FGM to improve the lifetime of Plasma Facing Components (PFC). To process W-Cu FGM, powder metallurgy route was analyzed and optimized from W-CuO powder mixtures. The influence of oxide reduction on the sintering of powder mixtures was highlighted. An optimal heating treatment under He/H 2 atmosphere was determined. The sintering mechanisms were deduced from the analysis of the effect of the Cu-content. Sintering of W-Cu materials with a graded composition and grain size has revealed two liquid migration steps: i) capillary migration, after the Cu-melting and, ii) expulsion of liquid, at the end of sintering, from the dense part to the porous part, due to the continuation of W-skeleton sintering. These two steps were confirmed by a model based on capillary pressure calculation. In addition, thermal conductivity measurements were conducted on sintered parts and showed values which gradually increase with the Cu-content. Hardness tests on a polished cross-section in the bulk are consistent with the composition profiles obtained and the differential grain size. (author)

  3. Influence of pre-heating on the surface modification of powder-metallurgy processed cold-work tool steel during laser surface melting

    Energy Technology Data Exchange (ETDEWEB)

    Šturm, Roman, E-mail: roman.sturm@fs.uni-lj.si [University of Ljubljana, Faculty of Mechanical Engineering, Aškerčeva 6, 1000 Ljubljana (Slovenia); Štefanikova, Maria [University of Ljubljana, Faculty of Mechanical Engineering, Aškerčeva 6, 1000 Ljubljana (Slovenia); Steiner Petrovič, Darja [Institute of Metals and Technology, Lepi pot 11, 1000 Ljubljana (Slovenia)

    2015-01-15

    Graphical abstract: - Highlights: • Heat-treatment protocol for laser surface melting of cold-work tool steel is proposed. • The laser melted steel surface is hardened, and morphologically modified. • The pre-heating of substrate creates a crack-and pore-free steel surface. • The optimum pre-heating temperature is determined to be 350 °C. • Using pre-heating the quantity of retained austenite is reduced. - Abstract: In this study we determine the optimal parameters for surface modification using the laser surface melting of powder-metallurgy processed, vanadium-rich, cold-work tool steel. A combination of steel pre-heating, laser surface melting and a subsequent heat treatment creates a hardened and morphologically modified surface of the selected high-alloy tool steel. The pre-heating of the steel prior to the laser surface melting ensures a crack- and pore-free modified surface. Using a pre-heating temperature of 350 °C, the extremely fine microstructure, which typically evolves during the laser-melting, became slightly coarser and the volume fraction of retained austenite was reduced. In the laser-melted layer the highest values of microhardness were achieved in the specimens where a subsequent heat treatment at 550 °C was applied. The performed thermodynamic calculations were able to provide a very valuable assessment of the liquidus temperature and, especially, a prediction of the chemical composition as well as the precipitation and dissolution sequence for the carbides.

  4. Powder Metallurgy Processing of a WxTaTiVCr High-Entropy Alloy and Its Derivative Alloys for Fusion Material Applications.

    Science.gov (United States)

    Waseem, Owais Ahmed; Ryu, Ho Jin

    2017-05-16

    The W x TaTiVCr high-entropy alloy with 32at.% of tungsten (W) and its derivative alloys with 42 to 90at.% of W with in-situ TiC were prepared via the mixing of elemental W, Ta, Ti, V and Cr powders followed by spark plasma sintering for the development of reduced-activation alloys for fusion plasma-facing materials. Characterization of the sintered samples revealed a BCC lattice and a multi-phase structure. The selected-area diffraction patterns confirmed the formation of TiC in the high-entropy alloy and its derivative alloys. It revealed the development of C15 (cubic) Laves phases as well in alloys with 71 to 90at.% W. A mechanical examination of the samples revealed a more than twofold improvement in the hardness and strength due to solid-solution strengthening and dispersion strengthening. This study explored the potential of powder metallurgy processing for the fabrication of a high-entropy alloy and other derived compositions with enhanced hardness and strength.

  5. The effect of annealing temperature on the properties of powder metallurgy processed Ti-35Nb-2Zr-0.5O alloy.

    Science.gov (United States)

    Málek, Jaroslav; Hnilica, František; Veselý, Jaroslav; Smola, Bohumil; Medlín, Rostislav

    2017-11-01

    Ti-35Nb-2Zr-0.5O (wt%) alloy was prepared via a powder metallurgy process (cold isostatic pressing of blended elemental powders and subsequent sintering) with the primary aim of using it as a material for bio-applications. Sintered specimens were swaged and subsequently the influence of annealing temperature on the mechanical and structural properties was studied. Specimens were annealed at 800, 850, 900, 950, and 1000°C for 0.5h and water quenched. Significant changes in microstructure (i.e. precipitate dissolution or grain coarsening) were observed in relation to increasing annealing temperature. In correlation with those changes, the mechanical properties were also studied. The ultimate tensile strength increased from 925MPa (specimen annealed at 800°C) to 990MPa (900°C). Also the elongation increased from ~ 13% (800°C) to more than 20% (900, 950, and 1000°C). Copyright © 2017 Elsevier Ltd. All rights reserved.

  6. Physical metallurgy. Vol. 6. Corrosion, oxidation and physical metallurgy applications

    International Nuclear Information System (INIS)

    Adda, Y.; Dupuy, J.M.; Philibert, J.; Quere, Y.

    1982-12-01

    This document deals with the following subjects: oxidation, corrosion and surface treatments. Some physical metallurgy applications are presented: aluminium alloys, high elastic limit materials, materials for very high temperature, nuclear metallurgy problems, composite materials, magnetic materials, very high purity materials, and, superconductor materials [fr

  7. A non-destructive synchrotron X-ray study of the metallurgy and manufacturing processes of Eastern and Western astrolabes in the Adler Planetarium collection

    Science.gov (United States)

    Newbury, Brian Dale

    The astrolabe collection of the Adler Planetarium and History of Astronomy Museum, Chicago, IL, was examined using non-destructive synchrotron based high-energy X-ray techniques including diffraction, fluorescence, and radiography to determine the metallurgy, microstructure, and metal forming processes used in astrolabe construction. All high-energy X-ray measurements were performed at the Advanced Photon Source (APS) synchrotron of Argonne National Laboratory, Argonne, IL. Astrolabes from the collection were selected to represent all major astrolabe production centers possible and time periods. It was found that all European astrolabes were manufactured of traditional cementation brass by hand worked metal forming processes consistent with technology in the literature. Of the Islamic astrolabes examined, all seven from Lahore in current-day Pakistan exhibited advanced brass alloys not typical of alloys discussed in the literature. It was found that these alloys were selected for their specific hot working properties, allowing the Lahore metalworkers to more efficiently make brass sheet from which to make astrolabe components. In addition, the alloy required a fundamental change in the brass foundry process, indicating advanced Zn metal production techniques. It was found that analysis by high energy X-rays from the APS was essential to produce data on the chemistry and microstructure from the interior of the astrolabe components in a non-destructive manner. Many astrolabe components had undergone surface dezincification due to heavy annealing during manufacturing, causing the Zn composition measured by the surface sensitive fluorescence technique to be lower than the true bulk alloy Zn composition. This would have been impossible to quantify non-destructively without the high-energy diffraction capability of the APS. The results of this study have proven the effectiveness of the synchrotron as a viable non-destructive analysis technique for examining cultural

  8. Metallurgical aspects of welding. Ferrous and nonferrous materials. 4. new rev. ed.

    International Nuclear Information System (INIS)

    Schulze, Guenter

    2010-01-01

    This is the fourth edition of the standard work on welding metallurgy. The various problems of ferrous and nonferrous materials in the welding process are presented in great detail. In order to prevent corrosion of welded constructions, metallurgical properties and problems of all important technical materials are discussed, i.e. alloyed and unalloyed steels, cast iron materials, and the most relevant nonferrous materials. At the end of each chapter, the interested reader will find exercises for self-studies. Some of these can be solved using the material presented in the book while others are intended for deepening and further training. Easy examples (with solutions) are found all over the book; they are helpful because they provide information on underlying mechanisms and interdependences that are not obvious at first glance. The information was adapted to new EURO standards and international standards (up to March 2009) as far as these are relevant to Germany. New information is provided, e.g., on new steel standards (constructional steels according to DIN EN 10025), heat-treatable steels according to DIN EN 10025-6 and DIN EN 10083, high-alloy steels according to DIN EN 10088, and filler materials for steel welding according to DIN EN ISO 2560. The systematics of the ''law of cohabitation'' was applied to welding engineering for the first time here. (orig.) [de

  9. Thermogravimetric control of intermediate compounds in uranium metallurgy

    International Nuclear Information System (INIS)

    Gasco Sanchez, L.; Fernandez Cellini, R.

    1959-01-01

    The thermal decomposition of some intermediate compounds in the metallurgy of the uranium as uranium peroxide, ammonium uranate, uranium and ammonium penta-fluoride, uranium tetrafluoride and uranous oxide has been study by means of the Chevenard's thermo balance. Some data on pyrolysis of synthetic mixtures of intermediate compounds which may occasionally appear during the industrial process, are given. Thermogravimetric methods of control are suggested, usable in interesting products in the uranium metallurgy. (Author) 20 refs

  10. Organic contaminants degradation from the S(IV) autoxidation process catalyzed by ferrous-manganous ions: A noticeable Mn(III) oxidation process.

    Science.gov (United States)

    Zhang, Jiaming; Ma, Jun; Song, Haoran; Sun, Shaofang; Zhang, Zhongxiang; Yang, Tao

    2018-04-15

    Remarkable atrazine degradation in the S(IV) autoxidation process catalyzed by Fe 2+ -Mn 2+ (Fe 2+ /Mn 2+ /sulfite) was demonstrated in this study. Competitive kinetic experiments, alcohol inhibiting methods and electron spin resonance (ESR) experiments proved that sulfur radicals were not the major oxidation species. Mn(III) was demonstrated to be the primary active species in the Fe 2+ /Mn 2+ /sulfite process based on the comparison of oxidation selectivity. Moreover, the inhibiting effect of the Mn(III) hydrolysis and the S(IV) autoxidation in the presence of organic contaminants indicated the existence of three Mn(III) consumption routes in the Fe 2+ /Mn 2+ /sulfite process. The absence of hydroxyl radical and sulfate radical was interpreted by the competitive dynamics method. The oxidation capacity of the Fe 2+ /Mn 2+ /sulfite was independent of the initial pH (4.0-6.0) because the fast decay of S(IV) decreased initial pH below 4.0 rapidly. The rate of ATZ degradation was independent of the dissolved oxygen (DO) because that the major DO consumption process was not the rate determining step during the production of SO 5 •- . Phosphate and bicarbonate were confirmed to have greater inhibitory effects than other environmental factors because of their strong pH buffering capacity and complexing capacity for Fe 3+ . The proposed acetylation degradation pathway of ATZ showed the application of the Fe 2+ /Mn 2+ /sulfite process in the research of contaminants degradation pathways. This work investigated the characteristics of the Fe 2+ /Mn 2+ /sulfite process in the presence of organic contaminants, which might promote the development of Mn(III) oxidation technology. Copyright © 2018. Published by Elsevier Ltd.

  11. Application of laser in powder metallurgy

    International Nuclear Information System (INIS)

    Tolochko, N.K.

    1995-01-01

    Modern status of works in the field of laser application in powder metallurgy (powders preparation, sintering, coatings formation, powder materials processing) is considered. The attention is paid to the new promising direction in powder products shape-formation technology - laser layer-by-layer selective powders sintering and bulk sintering of packaged layered profiles produced by laser cutting of powder-based sheet blanks. 67 refs

  12. Research on deeply purifying effluent from uranium mining and metallurgy to remove uranium by ion exchange. Pt.2: Elution uranium from lower loaded uranium resin by the intense fractionation process

    International Nuclear Information System (INIS)

    Zhang Jianguo; Chen Shaoqiang; Qi Jing

    2002-01-01

    Developing macroporous resin for purifying uranium effluent from uranium mining and metallurgy is presented. The Intense Fractionation Process is employed to elute uranium from lower loaded uranium resin by the eluent of sulfuric acid and ammonium sulfate. The result is indicated that the uranium concentration in the rich elutriant is greatly increased, and the rich liquor is only one bed column volume, uranium concentration in the elutriant is increased two times which concentration is 10.1 g/L. The eluent is saved about 50% compared with the conventional fixed bed elution operation. And also the acidity in the rich elutriant is of benefit to the later precipitation process in uranium recovery

  13. Current programmes of Metallurgy Division (1991)

    International Nuclear Information System (INIS)

    1991-01-01

    Current research and development programmes of the Metallurgy Division are listed under the headings: 1)Thrust Areas, 2)High Temperature Materials Section, 3)Chemical Metallurgy Section, 4)Metallurgical Thermochemistry Section, 5)Physical Metallurgy Section, 6)Mechanical Metallurgy Section, 7)Corrosion Metallurgy Section, 8)Electrochemical Science and Technology Section, 9)Ceramics Section, and 10)Fabrication and Maintenance Group. A list of equipment in the Division and a list of sciientific personnel of the Division are also given. (M.G.B.)

  14. Effect of processing parameters on the magnetic properties and microstructures of molybdenum permalloy compacts made by powder metallurgy

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Zhangming; Xu, Wei; Guo, Ting; Jiang, Yinzhu; Yan, Mi, E-mail: mse_yanmi@zju.edu.cn

    2014-05-01

    Highlights: • Effect of processing parameters on the properties of MP powder cores was studied. • Effective magnetic permeability was enhanced from 45 to 160 after annealing. • A core loss of 780 mw/cm{sup 3} (100 kHz, 100 mT) was obtained. - Abstract: Effects of compaction and annealing process on the magnetic properties and microstructures of molybdenum permalloy (MP) powder cores have been investigated. MP compacts, with density as high as 92% of the theoretical value, were obtained under 1800 MPa compaction pressure. The MP powder cores show an enhanced effective magnetic permeability of 160 after post-annealing at 690 °C, which is attributed to the relief of internal stress rather than the phase transformation evidenced by the XRD analysis. However, higher annealing temperature destroys the insulating layer, resulting in the drop of the electrical resistivity, the effective magnetic permeability as well as the frequency stability. The results show that the samples compacted at 1800 MPa and annealed at 690 °C exhibit excellent magnetic properties, with core loss of 780 mw/cm{sup 3} (100 kHz, 100 mT) and effective magnetic permeability of 160 whose frequency stability is up to 1 MHz.

  15. Lithium extractive metallurgy

    International Nuclear Information System (INIS)

    Josa, J.M.; Merino, J.L.

    1985-01-01

    The Nuclear Fusion National Program depends on lithium supplies. Extractive metallurgy development is subordinate to the localization and evaluation of ore resources. Nowadays lithium raw materials usable with present technology consist of pegmatite ore and brine. The Instituto Geologico y Minero Espanol (IGME) found lepidolite, ambligonite and spodrimene in pegmatite ores in different areas of Spain. However, an evaluation of resources has not been made. Different Spanish surface and underground brines are to be sampled and analyzed. If none of these contain significant levels of lithium, the Junta de Energia Nuclear (JEN) will try an agreement with IGME for ENUSA (Empresa Nacional del Uranio, S.A.) to explore pegmatite-ore bodies from different locations. Different work stages, laboratory tests, pilots plants tests and commercial plant, are foreseen, if the deposits are found. (author)

  16. Synthesis, mechanical properties and corrosion behavior of powder metallurgy processed Fe/Mg2Si composites for biodegradable implant applications.

    Science.gov (United States)

    Sikora-Jasinska, M; Paternoster, C; Mostaed, E; Tolouei, R; Casati, R; Vedani, M; Mantovani, D

    2017-12-01

    Recently, Fe and Fe-based alloys have shown their potential as degradable materials for biomedical applications. Nevertheless, the slow corrosion rate limits their performance in certain situations. The shift to iron matrix composites represents a possible approach, not only to improve the mechanical properties, but also to accelerate and tune the corrosion rate in a physiological environment. In this work, Fe-based composites reinforced by Mg 2 Si particles were proposed. The initial powders were prepared by different combinations of mixing and milling processes, and finally consolidated by hot rolling. The influence of the microstructure on mechanical properties and corrosion behavior of Fe/Mg 2 Si was investigated. Scanning electron microscopy and X-ray diffraction were used for the assessment of the composite structure. Tensile and hardness tests were performed to characterize the mechanical properties. Potentiodynamic and static corrosion tests were carried out to investigate the corrosion behavior in a pseudo-physiological environment. Samples with smaller Mg 2 Si particles showed a more homogenous distribution of the reinforcement. Yield and ultimate tensile strength increased when compared to those of pure Fe (from 400MPa and 416MPa to 523MPa and 630MPa, respectively). Electrochemical measurements and immersion tests indicated that the addition of Mg 2 Si could increase the corrosion rate of Fe even twice (from 0.14 to 0.28mm·year -1 ). It was found that the preparation method of the initial composite powders played a major role in the corrosion process as well as in the corrosion mechanism of the final composite. Copyright © 2017 Elsevier B.V. All rights reserved.

  17. Powder metallurgy bearings for advanced rocket engines

    Science.gov (United States)

    Fleck, J. N.; Killman, B. J.; Munson, H.E.

    1985-01-01

    Traditional ingot metallurgy was pushed to the limit for many demanding applications including antifriction bearings. New systems require corrosion resistance, better fatigue resistance, and higher toughness. With conventional processing, increasing the alloying level to achieve corrosion resistance results in a decrease in other properties such as toughness. Advanced powder metallurgy affords a viable solution to this problem. During powder manufacture, the individual particle solidifies very rapidly; as a consequence, the primary carbides are very small and uniformly distributed. When properly consolidated, this uniform structure is preserved while generating a fully dense product. Element tests including rolling contact fatigue, hot hardness, wear, fracture toughness, and corrosion resistance are underway on eleven candidate P/M bearing alloys and results are compared with those for wrought 440C steel, the current SSME bearing material. Several materials which offer the promise of a significant improvement in performance were identified.

  18. Obtainment of the alloy Cu13Al4Ni using processed by powder metallurgy; Obtencao da liga Cu13Al4Ni via metalurgia do po

    Energy Technology Data Exchange (ETDEWEB)

    Grossi, L.J.; Damasceno, N.; Muterlle, P.V., E-mail: larajgrossi@yahoo.com.br [Universidade de Brasilia (UnB), Brasilia, DF (Brazil). Departamento de Engenharia Mecanica

    2016-07-01

    The powder metallurgy is a technique environmentally advantageous that allows the production of many pieces, with a good superficial finishing and dimensional tolerance. For the production of pieces using technique, basics steps are carried out, as the characterization of powders, the mixing and homogenization, compacting and sintering. In this context, this work has as objective the obtainment of the Cu13Al4Ni alloy via powder metallurgy. For this, was made a high energy milling for 2, 4 and 8 hours. Then, the milled powder was compacted and posteriorly, sintered in an oven with controlled atmosphere. It was observed that the milling time affects directly in sintering of the pieces. The best results obtained were for the samples that were milled for 4 hours. This samples have showed 21, 52% of porosity and 6,382 g/cm³ of the density of sintered. (author)

  19. Variations of 57Fe hyperfine parameters in medicaments containing ferrous fumarate and ferrous sulfate

    International Nuclear Information System (INIS)

    Oshtrakh, M. I.; Novikov, E. G.; Dubiel, S. M.; Semionkin, V. A.

    2010-01-01

    Several commercially available medicaments containing ferrous fumarate (FeC 4 H 2 O 4 ) and ferrous sulfate (FeSO 4 ), as a source of ferrous iron, were studied using a high velocity resolution Mössbauer spectroscopy. A comparison of the 57 Fe hyperfine parameters revealed small variations for the main components in both medicaments indicating some differences in the ferrous fumarates and ferrous sulfates. It was also found that all spectra contained additional minor components probably related to ferrous and ferric impurities or to partially modified main components.

  20. Variations of {sup 57}Fe hyperfine parameters in medicaments containing ferrous fumarate and ferrous sulfate

    Energy Technology Data Exchange (ETDEWEB)

    Oshtrakh, M. I., E-mail: oshtrakh@mail.utnet.ru; Novikov, E. G. [Ural Federal University (The former Ural State Technical University-UPI), Faculty of Physical Techniques and Devices for Quality Control (Russian Federation); Dubiel, S. M. [AGH University of Science and Technology, Faculty of Physics and Computer Science (Poland); Semionkin, V. A. [Ural Federal University (The former Ural State Technical University-UPI), Faculty of Physical Techniques and Devices for Quality Control (Russian Federation)

    2010-04-15

    Several commercially available medicaments containing ferrous fumarate (FeC{sub 4}H{sub 2}O{sub 4}) and ferrous sulfate (FeSO{sub 4}), as a source of ferrous iron, were studied using a high velocity resolution Moessbauer spectroscopy. A comparison of the {sup 57}Fe hyperfine parameters revealed small variations for the main components in both medicaments indicating some differences in the ferrous fumarates and ferrous sulfates. It was also found that all spectra contained additional minor components probably related to ferrous and ferric impurities or to partially modified main components.

  1. Ion implanting ferrous metals to improve corrosion resistance

    International Nuclear Information System (INIS)

    Dearnaley, G.; Goode, P.D.

    1981-01-01

    A process is described for the treatment of a surface of a ferrous article to improve its corrosion resistance, wherein the surface is subjected to ion bombardment at a temperature above one hundred degrees centigrade in an evacuated enclosure which contains a residual quantity of gaseous oxygen. (author)

  2. Powder metallurgy development at SRL

    International Nuclear Information System (INIS)

    Peacock, H.B.

    1978-01-01

    Fuel for Savannah River Plant (SRP) reactors consists of extruded tubes with aluminum--uranium alloy cores clad with 8001 aluminum. The 235 U in the fuel is periodically recovered and recycled in new fuel assemblies. The buildup of 236 U in the enriched uranium requires increased total uranium contents to maintain reactivity in existing assembly designs. High level waste production from these tubes is proportional to the aluminum content; therefore, appreciable radioactive waste reductions result from lower aluminum--uranium ratios and thinner clad tubes. The casting process now used for fuel cores is limited to below 40 wt % U because of the reduced fabricability of high uranium alloys. To increase tube loading and reduce aluminum, the U 3 O 8 -Al powder metallurgy (P/M) process for fuel tubes is under development. Several fabricaion and irradiaion tests have been made using production conditions. Both small scale and production tests carried out at SRL for high-density P/M fuel development are discussed

  3. Application of tracer techniques and technical means in ferrous, non-ferrous and hydrometallurgy

    International Nuclear Information System (INIS)

    Chizhek, L.; Myshak, F.; Shtrba, J.

    1979-01-01

    Brief data are given about the results of joint investigations and developments of the problems of radioisotope methods and technical means application in ferrous and hydrometallurgy, obtained during the period of 1976-1977. Development of these problems was done in the frameworks of the plan of scientific and technical cooperation of the CMEA member-states and Yugoslavia. Results are given of the development of following themes: investigation of metallurgic processes by means of activation analysis; investidations of metallurgic processes by means of autoradiography and X-ray feuorescent analysis; control and automatization of metallurgic processes by means of radioisotope instruments; investigation of processes of melting of cast iron and steel as well as of processes of treatment of metals by means of the radioactive indicators method, activation analysis and radioisotope instruments; application of the radioisotope methods and technical means for investigation of processes of production of non-ferrous metals; application of the radioisotope methods for investigations of the hydrometallurgy processes [ru

  4. Development of processes for zircaloy chips recycling by electric arc furnace remelting and powder metallurgy; Desenvolvimento de processos de reciclagem de cavacos de zircaloy via refusao em forno eletrico a arco e metalurgia do po

    Energy Technology Data Exchange (ETDEWEB)

    Pereira, Luiz Alberto Tavares

    2014-09-01

    PWR reactors employ, as nuclear fuel, UO{sub 2} pellets with Zircaloy clad. In the fabrication of fuel element parts, machining chips from the alloys are generated. As the Zircaloy chips cannot be discarded as ordinary metallic waste, the recycling of this material is important for the Brazilian Nuclear Policy, which targets the reprocess of Zircaloy residues for economic and environmental aspects. This work presents two methods developed in order to recycle Zircaloy chips. In one of the methods, Zircaloy machining chips were refused using an electric-arc furnace to obtain small laboratory ingots. The second one uses powder metallurgy techniques, where the chips were submitted to hydriding process and the resulting material was milled, isostatically pressed and vacuum sintered. The ingots were heat-treated by vacuum annealing. The microstructures resulting from both processing methods were characterized using optical and scanning electron microscopy. Chemical composition, crystal phases and hardness were also determined. The results showed that the composition of recycled Zircaloy comply with the chemical specifications and presented adequate microstructure for nuclear use. The good results of the powder metallurgy method suggest the possibility of producing small parts, like cladding end-caps, using near net shape sintering. (author)

  5. Emission of PCDD/Fs and dioxin-like PCBs from metallurgy industries in S. Korea.

    Science.gov (United States)

    Yu, Byeong-Woon; Jin, Guang-Zhu; Moon, Young-Hoon; Kim, Min-Kwan; Kyoung, Jong-Dai; Chang, Yoon-Seok

    2006-01-01

    The metallurgy industry and municipal waste incinerators are considered the main sources of polychlorinated dibenzo-p-dioxin and dibenzofurans (PCDD/Fs) in many countries. This study investigated the emission factors and total emissions of PCDD/Fs and dioxin-like polychlorinated biphenyls (PCBs) emitted from metallurgy industries (including ferrous and nonferrous foundries) in Korea. The toxic equivalency (TEQ) emission factor of PCDD/Fs was the highest for secondary copper production, at 24451 ng I-TEQ/ton. The total estimated emissions of PCDD/Fs from these sources were 35.259 g I-TEQ/yr, comprising 0.088 g I-TEQ/yr from ferrous foundries, 31.713 g I-TEQ/yr from copper production, 1.716 g I-TEQ/yr from lead production, 0.111 g I-TEQ/yr from zinc production, and 1.631 g I-TEQ/yr from aluminum production. The total estimated annual amounts of dioxin-like PCBs emitted from these sources were 13.260 g WHO-TEQ/yr, comprising 0.014 g WHO-TEQ/yr from ferrous foundries, 12.675 g WHO-TEQ/yr from copper production, 0.170 g WHO-TEQ/yr from lead production, 0.017 g WHO-TEQ/yr from zinc production, and 0.384 g WHO-TEQ/yr from aluminum production. The highest emission factor was found for secondary copper smelting, at 9770 ng WHO-TEQ/ton.

  6. Metallography of powder metallurgy materials

    International Nuclear Information System (INIS)

    Lawley, Alan; Murphy, Thomas F.

    2003-01-01

    The primary distinction between the microstructure of an ingot metallurgy/wrought material and one fabricated by the powder metallurgy route of pressing followed by sintering is the presence of porosity in the latter. In its various morphologies, porosity affects the mechanical, physical, chemical, electrical and thermal properties of the material. Thus, it is important to be able to characterize quantitatively the microstructure of powder metallurgy parts and components. Metallographic procedures necessary for the reliable characterization of microstructures in powder metallurgy materials are reviewed, with emphasis on the intrinsic challenges presented by the presence of porosity. To illustrate the utility of these techniques, five case studies are presented involving powder metallurgy materials. These case studies demonstrate problem solving via metallography in diverse situations: failure of a tungsten carbide-coated precipitation hardening stainless steel, failure of a steel pump gear, quantification of the degree of sinter (DOS), simulation of performance of a porous filter using automated image analysis, and analysis of failure in a sinter brazed part assembly

  7. Basic metallurgy for nondestructive testing

    International Nuclear Information System (INIS)

    Abdul Nassir Ibrahim; Azali Muhammad; Ab. Razak Hamzah; Abd. Aziz Mohamed; Mohamad Pauzi Ismail

    2008-01-01

    For this chapter, reader will be served with the basic knowledge on metallurgy for nondestructive testing. One the main application of nondestructive testing is to detect discontinuity of mass defect in metal. As we already know, metal are widely used in many application such as in building as a system, component and engineering product. Steel and iron are metal that usually used in industry, especially heavy industry such as gas and petroleum industry, chemistry, electric generation, automobile, and military device. Based on this, basic knowledge on metallurgy must need by NDT practitioner. The combination between metallurgy and datas from radiography testing can make radiographer good interpretation on quality of the metal inspected and can used to make a good decision either to accept or not certain product, system or components.

  8. RECYCLING OF FERROUS METAL SHAVINGS

    Directory of Open Access Journals (Sweden)

    S. L. Rovin

    2017-01-01

    Full Text Available The most advanced and universal way of chips recycling of ferrous metals is the technology of direct chips remelting in rotational tilting furnaces (RBF directly at the enterprises-sources of waste generation. However common practice of iron and steel chips recycling is based on its briquetting and subsequent remelting in traditional furnaces.For cost reduction when chip briquetting and organization of hot briquetting sections in places of its formation highly efficient equipment – rotational dryer and RBF is proposed. The possibility and effectiveness of developed furnaces for lowand high-temperature chip heating in briquetting lines is proved. Thermal efficiency of such furnaces when dispersed materials heating is much higher than drum or feed-through furnaces. Hot briquetting of shavings reduces the pressing force, which reduces the specific energy consumption. The use of rotary kilns can reduce technological operations and equipment of production sites for the manufacture of briquettes

  9. Physical metallurgy of titanium alloys

    International Nuclear Information System (INIS)

    Collings, E.W.

    1988-01-01

    Researches in electric, magnetic, thermophysical properties of titanium alloys in the wide range of temperatures (from helium upto elevated one), as well as stability of phases in alloys of different types are generalized. Fundamental description of physical properties of binary model alloys is given. Acoustic emission, shape memory and Bauschinger effects, pseudoelasticity, aging and other aspects of physical metallurgy of titanium alloys are considered

  10. Sinterability and microstructure evolution during sintering of ferrous powder mixtures

    Directory of Open Access Journals (Sweden)

    Kétner Bendo Demétrio

    2013-01-01

    Full Text Available The present work is focused on ferrous powder metallurgy and presents some results of a development of a suitable masteralloy for use as an additive to iron powder for the production of sintered steels. The masteralloy was produced by melting a powder mixture containing approximately Fe + 20% Ni + 20% Mn + 20% Si + 1% C (wt%, in order to obtain a cast billet that was converted into fine powder by crushing and milling. It was observed presence of SiC in the masteralloy after melting that is undesirable in the alloy. Si element should be introduced by using ferrosilicon. Sintered alloys with distinct contents of alloying elements were prepared by mixing the masteralloy powder to plain iron powder. Samples were produced by die compaction of the powder mixtures and sintering at 1200 °C in a differential dilatometer in order to record their linear dimensional behaviour during heating up and isothermal sintering, aiming at studying the sinterability of the compacts. Microstructure development during sintering was studied by SEM, XRD and microprobe analyses.

  11. Adsorption of ferrous ions onto montmorillonites

    Energy Technology Data Exchange (ETDEWEB)

    Qin, Dawei, E-mail: qdw109@163.com [Qilu University of Technology, Jinan, 250353, Shandong (China); Niu, Xia [Qilu University of Technology, Jinan, 250353, Shandong (China); Qiao, Min; Liu, Gang; Li, Hongxin; Meng, Zhenxiao [Shandong SiBang pharmaceutical co., LTD, Jinan, Shandong, 250200 (China)

    2015-04-01

    Highlights: • Adsorption study of ferrous ions on montmorillonites. • Using ascorbic acid as antioxidants in adsorption process. • Fe (II)-MMT had good affinity for phosphate. - Abstract: The adsorption of Fe (II) onto montmorillonites was investigated through initial concentration, contact time, pH and temperature. During the whole adsorption process, the ascorbic acid (Vitamin C) was added as a kind of antioxidant, at the same time, deionized water (after boiling) and nitrogen protection were also used to avoid oxidation. The Fe{sup 2+}/Fe{sub total} ratio of the iron exists in the Fe-montmorillonites was found more than 95%. Two kinetic models, including pseudo-first-order and pseudo-second-order model, were used to analyze the adsorption process of Fe (II) on montmorillonites. The results of our study showed that adsorption process fitted with pseudo-second-order well. Adsorption isotherms showed that Langmuir model was better than Freundlich model. The thermodynamic parameters ΔG{sup 0} and ΔH{sup 0} were 3.696 kJ/mol and 6.689 kJ/mol (we just gave the values at 298 K), respectively. The positive values at different temperatures showed that the adsorption process was non-spontaneous and endothermic. The characteristics of materials were determined by X-ray diffraction (XRD), Fourier transform infrared (FT-IR), Surface area and porosity analyzer, Thermogravimetric analysis (TGA), Differential scanning calorimeter (DSC) and Zeta potential distribution.

  12. One step HIP canning of powder metallurgy composites

    Science.gov (United States)

    Juhas, John J. (Inventor)

    1990-01-01

    A single step is relied on in the canning process for hot isostatic pressing (HIP) powder metallurgy composites. The binders are totally removed while the HIP can of compatible refractory metal is sealed at high vacuum and temperature. This eliminates outgassing during hot isostatic pressing.

  13. Evaluation of powder metallurgy superalloy disk materials

    Science.gov (United States)

    Evans, D. J.

    1975-01-01

    A program was conducted to develop nickel-base superalloy disk material using prealloyed powder metallurgy techniques. The program included fabrication of test specimens and subscale turbine disks from four different prealloyed powders (NASA-TRW-VIA, AF2-1DA, Mar-M-432 and MERL 80). Based on evaluation of these specimens and disks, two alloys (AF2-1DA and Mar-M-432) were selected for scale-up evaluation. Using fabricating experience gained in the subscale turbine disk effort, test specimens and full scale turbine disks were formed from the selected alloys. These specimens and disks were then subjected to a rigorous test program to evaluate their physical properties and determine their suitability for use in advanced performance turbine engines. A major objective of the program was to develop processes which would yield alloy properties that would be repeatable in producing jet engine disks from the same powder metallurgy alloys. The feasibility of manufacturing full scale gas turbine engine disks by thermomechanical processing of pre-alloyed metal powders was demonstrated. AF2-1DA was shown to possess tensile and creep-rupture properties in excess of those of Astroloy, one of the highest temperature capability disk alloys now in production. It was determined that metallographic evaluation after post-HIP elevated temperature exposure should be used to verify the effectiveness of consolidation of hot isostatically pressed billets.

  14. Ferrous alloy metallurgy - liquid lithium corrosion and welding. Progress report, January 1-December 31, 1980

    International Nuclear Information System (INIS)

    Olson, D.L.; Matlock, D.K.

    1980-01-01

    Fatigue crack growth has been used to evaluate the interaction between liquid lithium and an imposed stress. Fatigue crack growth data on type 304L stainless steel at 700C and 2 1/4Cr-1Mo steel between 500 and 700C show that for all imposed test conditions (i.e. frequency, temperature, and nitrogen content in the lithium) the interaction of lithium with the strain at the crack tip results in enhanced crack growth rates. The enhanced growth rates result from the effects of either enhanced grain boundary penetration or a change in crack propagation mechanism due to liquid metal embrittlement. Auger spectroscopy of grain boundary penetrated specimen shows that a lithium-oxygen compound forms at the grain boundary. Moessbauer evaluations of the ferrite layer of corroded type 304 stainless steel are being used to develop a model for weight loss in liquid lithium. The welding research in progress is directed to characterize the influence of variations of the austenitic weld metal composition on the microstructural and mechanical properties of dissimilar metal weldments. Weldments of 2 1/4Cr-1Mo steel to 316 stainless steel have been investigated for fusion microstructure, thermal expansion impact strength and characterization of specific long time in-service failures. Modification of weld metal microstructures by microalloy additions is being investigated as a concept to improve weld metal properties. The behavior of a strip electrode in a gas metal arc is being investigated to determine the feasibility of gas metal arc weld strip overlay cladding

  15. Investigation of mechanisms of dechlorination of archaeological ferrous objects corroded in marine environment. Case of processing in aerated and deaerated alkaline solutions

    International Nuclear Information System (INIS)

    Kergourlay, Florian

    2012-01-01

    After a bibliographic study on the present knowledge on dechlorination mechanisms within corrosion layers of archaeological objects of submarine origin, this research thesis presents an analytical methodology which comprises characterization experimental techniques (from optical microscopy to Raman spectroscopy) and in situ investigation of the evolution of the corrosion layer during a processing under synchrotron radiation. The obtained results are then presented and discussed: morphological, elemental and structural characteristics. The author also compares the corrosion system between an object recently taken out of water and an object which has been air dried. He also comments and discusses the in situ observation by X ray diffraction under micro-beam of the evolution of the corrosion system during the processing. The ex situ characterization of corrosion systems after the rinsing and drying steps (after processing) is reported. Results are discussed in terms of thermodynamics. A kinetic approach is proposed

  16. The utilization of mechanochemistry in the extractive metallurgy and at the nanocrystalline materials preparation

    Directory of Open Access Journals (Sweden)

    Boldižárová Eva

    2002-03-01

    Full Text Available The possibility of the application of mechanochemistry in the extractive metallurgy and the nanocrystalline materials preparation is studied. The aim of the experiments is the chloride leaching of a complex sulphidic CuPbZn concentrate (Hodruša-Hámre, the modification of properties of CaCO3 (Yauli, Peru for zinc sorption from model solutions and the mechanochemical reduction of copper sulphide by elemental iron.The chloride leaching of mechanically activated complex sulphidic CuPbZn concentrate is a selective process. While the recoveries of copper, lead and zinc are 65-85 %, the recoveries of silver and gold are less than 7 % and 2 %, respectively.The positive influence of CaCO3 mechanical activation for zinc sorption from ZnSO4 solution was observed. While only 58 % of zinc sorption was determined after 30 minutes for a non-activated sample, 98 % of zinc sorption was determined after 3 minutes sorption for the sample mechanically activated for 15 minutes.By the mechanochemical reduction of copper sulphide with iron, nanocrystalline copper and iron sulphide are formed. This reaction is an example of the new “solid state technology“, where chemical processes in the gaseous and liquid states are excluded.The results can serve as a contribution to the optimization of copper, lead and zinc extraction from complex sulphidic concentrates, the increase of non-ferrous metals sorption efficiency on mineral sorbents as well as to the nanocrystalline copper preparation.The application of mechanical activation has grown in the laboratory research. The Institute of Geotechnics of SAS has also achieved significant theoretical results in study of mechanical activation of sulphides and their reactivity in the different solid-phase reactions with the effect on industrial applications. The Institute has developed the technology of mechanochemical leaching (process MELT which was successfully tested in a pilot plant unit.

  17. Metallurgy and foundry practice. German-English. With 40,000 citations. Metallurgie und Giessereitechnik. Deutsch-Englisch. Mit etwa 40,000 Wortstellen

    Energy Technology Data Exchange (ETDEWEB)

    Stoelzel, K [ed.

    1986-01-01

    The dictionary represents the German-English terminology of the broad field of metallurgy (the dressing of ores and fluxes, pig iron and steel making, powder and nonferrous metallurgy, forming processes etc.) as well as of the broad field of foundry practice. Apart from the theoretical fundamental principles emphasis is on the problems of materials working and materials testing. Moreover, the dictionary considers a number of technical terms concerning the hardening, surface treatment and corrosion of materials.

  18. A non-destructive surface burn detection method for ferrous metals based on acoustic emission and ensemble empirical mode decomposition: from laser simulation to grinding process

    International Nuclear Information System (INIS)

    Yang, Zhensheng; Wu, Haixi; Yu, Zhonghua; Huang, Youfang

    2014-01-01

    Grinding is usually done in the final finishing of a component. As a result, the surface quality of finished products, e.g., surface roughness, hardness and residual stress, are affected by the grinding procedure. However, the lack of methods for monitoring of grinding makes it difficult to control the quality of the process. This paper focuses on the monitoring approaches for the surface burn phenomenon in grinding. A non-destructive burn detection method based on acoustic emission (AE) and ensemble empirical mode decomposition (EEMD) was proposed for this purpose. To precisely extract the AE features caused by phase transformation during burn formation, artificial burn was produced to mimic grinding burn by means of laser irradiation, since laser-induced burn involves less mechanical and electrical noise. The burn formation process was monitored by an AE sensor. The frequency band ranging from 150 to 400 kHz was believed to be related to surface burn formation in the laser irradiation process. The burn-sensitive frequency band was further used to instruct feature extraction during the grinding process based on EEMD. Linear classification results evidenced a distinct margin between samples with and without surface burn. This work provides a practical means for grinding burn detection. (paper)

  19. Powder Metallurgy Facility

    Data.gov (United States)

    Federal Laboratory Consortium — The facility is uniquely equipped as the only laboratory within DA to conduct PM processing of refractory metals and alloys as well as the processing of a wide range...

  20. Production of ferrous sulfate from residue from the iron mining

    International Nuclear Information System (INIS)

    Cardoso, K.A; Riella, H.G.; Abreu, E.F.; Carvalho, E.F. Urano de; Durazzo, M.

    2012-01-01

    This paper was developed from a residue obtained by processing iron ore exploited by the mining company Samarco S/A. The residue was characterized and the analyses showed that it contains about 70% of the mineral hematite (Fe 2 O 3 ) and also that some economically important products could be produced. One is the ferrous sulfate that can be used in pharmaceuticals and also that can be used in the treatment of iron deficiency anemia. The iron, in addition to is importance for the industrial production of steel and parts in general, also has great biological importance in all living beings. In order to produce ferrous sulfate from the byproduct in question, it was developed a obtaining route using metallic iron as hematite reductor and sulfuric acid to form the salt. (author)

  1. Fast and effective analysis of ferrous and non-ferrous alloys by X-ray fluorescence

    International Nuclear Information System (INIS)

    Gomez Serra, Abelardo

    1987-01-01

    An empirical method for the integral analysis of any kind of alloys, ferrous and non-ferrous, is described. The method is based on the intensities relation of the mixed elements and is independent of the size, shape and presentation of the sample. By this procedure, alloys with iron, copper, aluminium or magnesium base can be fastly classified. (S.M.) [es

  2. Powder metallurgy development at SRL

    International Nuclear Information System (INIS)

    Peacock, H.B.

    1993-01-01

    The Savannah River Laboratory (SRL) is developing a powder metallurgy (P/M) process for manufacturing reactor-grade fuel tubes containing high wt % U 3 O 8 -Al cores clad with 8001 aluminum. The P/M cores are made by isostatic compaction. They are assembled in billets, outgassed, and hot-extruded using conventional coextrusion techniques. Cores have been compacted with up to 100% U3O 8 and tubes extruded with 80 wt % oxide cores. Irradiation tests have been made using P/M core tubes in the Savannah River reactors. These tubes contained U 3 O 8 concentrations up to 59 wt % and no significant swelling or blistering occurred. The tubes were irradiated to ∼ 40% burnup or 1.6x10 21 fissions/cc of core. This report discusses both small-scale and production tests for high-density P/M fuel development. The purpose of the P/M development program at SRL is to: determine the maximum U 3 O 8 content that can be fabricated into thin wall tubes, irradiate high-density tubes to high burnup and assess irradiation and dimensional stability, continue metal forming studies for extrusion and drawing, and evaluate hydrostatic extrusion and hydrostatically assisted drawing of P/M core tubes. Experimental results of testing the fuel assemblies performance so far indicate that: cores containing fine (-325 mesh) U 3 O 8 and aluminum powders can be made practically free of high-density areas using the outlined P/M pre blending and sieving techniques. U 3 O 8 -Al cores can be isostatically compacted with up to 100 wt U 3 O 8 and tubes successfully extruded with up to 80 wt oxide; fission gas blistering of U 3 O 8 -Al P/M tubes as indicated by the blister tests is a function of fissions/cc of U 3 O 8 in the core; Decreasing the fission density of oxide increases the threshold temperature for blister formation; U 3 O 8 -Al P/M fuel tubes with up to 59 wt U 3 O 8 have been successfully irradiated in SRP reactor to 1.6 x 10 21 fissions/cc of core or 7 x 10 20 fissions/cc of U 3 O 8 small

  3. Powder Metallurgy characteristics and application: state of the art

    International Nuclear Information System (INIS)

    Zaid, A.I.O.

    2005-01-01

    Powder metallurgy process (P/M) is a near-net or net-shape manufacturing process that combines the features of shape making technology of powder compaction with the development of final material and design properties (physical and mechanical) during subsequent densification or consolidation processes, e.g. sintering. It utilizes the metal powder or powders of metal alloys. In this paper, the major historical developments in P/M are reviewed and discussed. The main parameters involved in the process and their effects on the product characteristics are presented and discussed, which include: powders and methods of their production, particle size and shape, compressibility and additives, sintering temperature and time and finishing processes. The advantages and limitations of powder metallurgy are also presented and discussed. Finally, applications and future developments of the process are outlined and discussed. (author)

  4. Obtainment, machining and wear of metal matrix composites processed by powder metallurgy; Obtencao, usinagem e desgaste de materiais compositos de matriz metalica processados via metalurgia do po

    Energy Technology Data Exchange (ETDEWEB)

    Jesus, Edilson Rosa Barbosa de. E-mail: erbjesus@usp.br

    1998-07-01

    The aim of this investigation was the obtainment of metal matrix composites (MMC) by the route of powder metallurgy, and the valuation of these materials with relation to their machining and wear characteristics. Firstly, were obtained pure commercial aluminium matrix composites materials, with 5, 10 and 15% volumetric fraction of silicon carbide particles. Was also obtained a material without reinforcement particles in order to verify by comparison, the influence of addition of reinforcement particles. The obtained materials were characterized physics (hydrostatic density), mechanics (hardness and tensile tests) and microstructurally (optical microscopy and scanning electron microscopy). The results showed a homogeneous distribution of reinforcement particles in the composite, and improvement in the mechanical properties, mainly tensile strength (UTS) in comparison to the unreinforced material. After, tests were made to verify the materials behavior during machining and to check the performance of several tool materials (cemented carbide, ceramics and polycrystalline diamond). In these tests, values of the cutting force were measured by instrumented tool-holders. Phenomena such as tool wear, built-up edge formation and mechanism of chip formation were also observed and evaluated. The results from the cemented carbide tool tests, were utilised for the machinability index determination of each material. These results were applied to the Taylor equation and the equation constants for each material and test conditions were determined. The results showed that the inclusion of silicon carbide particles made extremely difficult the machining of the composites, and only with diamond tool, satisfactory results were obtained. At last, wear tests were performed to verify the influence of the reinforcement particles in the characteristics of wear resistance of the materials. The results obtained were utilized in the wear coefficient determination for each material. The

  5. Reduction of Tc(VII) and Np(V) in solution by ferrous iron. A laboratory study of homogeneous and heterogeneous redox processes

    International Nuclear Information System (INIS)

    Cui, D.; Eriksen, T.E.

    1996-03-01

    The redox chemistry of Technetium and Neptunium in deep groundwater systems has been studied under well controlled conditions in laboratory experiments. The measured redox potentials in anoxic deep groundwater systems are consistent with redox reactions between Fe(II) in solution and hydrous Fe(III)-oxide phases. The fracture filling material and groundwater in transmissive fractures in bedrock constitute two different compartments in the groundwater system and experiments were therefore carried out in homogeneous Fe(II) containing solutions and in heterogeneous mixtures of solution with Fe(II) containing solid mineral phases. Reduction of the strongly sorbing neptunyl cation (NpO 2 + ) and the slightly sorbing pertechnetate anion (TcO 4 - ) by Fe(II) in solution was found to proceed very slowly, if at all, in reaction vessels with hydrophobic inner surfaces. However, in the heterogeneous systems we observed surface mediated reduction to the slightly soluble ( -8 mol*dm -3 ) tetravalent (hydr)oxides TcO 2 *nH 2 O (=Tc(OH) 4 ) and NpO 2 *nH 2 O (=Np(OH) 4 ) by Fe(II) sorbed on quartz,precipitated Fe(OH) 2 (s), Fe(II)CO 3 (s) and Fe(II) bearing minerals such as magnetite, hornblende and Fe(II)-chlorite. It is concluded that surface mediated redox-reactions will be the most effective pathway for the reduction of Tc(VII) and Np(V) in deep groundwater systems. On exposure of the surface-precipitated tetravalent (hydr)oxides to air saturated groundwater solutions the oxidative dissolution was found to be a very slow process and high concentration of hydrogen peroxide was required for oxidative dissolution. The slow rate of oxidative dissolution is most probably due to kinetic suppression of the reactions between dissolved oxygen and the precipitated (hydr)oxides. The kinetic suppression is caused by competing redox reactions at the surface of the Fe(II)-bearing minerals which consumes the dissolved oxygen. 30 refs, 22 figs

  6. Reduction of Tc(VII) and Np(V) in solution by ferrous iron. A laboratory study of homogeneous and heterogeneous redox processes

    Energy Technology Data Exchange (ETDEWEB)

    Cui, D.; Eriksen, T.E. [Royal Inst. of Tech., Stockholm (Sweden). Dept. of Chemistry

    1996-03-01

    The redox chemistry of Technetium and Neptunium in deep groundwater systems has been studied under well controlled conditions in laboratory experiments. The measured redox potentials in anoxic deep groundwater systems are consistent with redox reactions between Fe(II) in solution and hydrous Fe(III)-oxide phases. The fracture filling material and groundwater in transmissive fractures in bedrock constitute two different compartments in the groundwater system and experiments were therefore carried out in homogeneous Fe(II) containing solutions and in heterogeneous mixtures of solution with Fe(II) containing solid mineral phases. Reduction of the strongly sorbing neptunyl cation (NpO{sub 2}{sup +}) and the slightly sorbing pertechnetate anion (TcO{sub 4}{sup -}) by Fe(II) in solution was found to proceed very slowly, if at all, in reaction vessels with hydrophobic inner surfaces. However, in the heterogeneous systems we observed surface mediated reduction to the slightly soluble (<10{sub -8} mol*dm{sup -3}) tetravalent (hydr)oxides TcO{sub 2}*nH{sub 2}O (=Tc(OH){sub 4}) and NpO{sub 2}*nH{sub 2}O (=Np(OH){sub 4}) by Fe(II) sorbed on quartz,precipitated Fe(OH){sub 2}(s), Fe(II)CO{sub 3}(s) and Fe(II) bearing minerals such as magnetite, hornblende and Fe(II)-chlorite. It is concluded that surface mediated redox-reactions will be the most effective pathway for the reduction of Tc(VII) and Np(V) in deep groundwater systems. On exposure of the surface-precipitated tetravalent (hydr)oxides to air saturated groundwater solutions the oxidative dissolution was found to be a very slow process and high concentration of hydrogen peroxide was required for oxidative dissolution. The slow rate of oxidative dissolution is most probably due to kinetic suppression of the reactions between dissolved oxygen and the precipitated (hydr)oxides. The kinetic suppression is caused by competing redox reactions at the surface of the Fe(II)-bearing minerals which consumes the dissolved oxygen.

  7. Removal of cyanide compounds from coking wastewater by ferrous sulfate: Improvement of biodegradability.

    Science.gov (United States)

    Yu, Xubiao; Xu, Ronghua; Wei, Chaohai; Wu, Haizhen

    2016-01-25

    The effect of ferrous sulfate (FeSO4) treatment on the removal of cyanide compounds and the improvement of biodegradability of coking wastewater were investigated by varying Fe:TCN molar ratios. Results suggested that the reaction between FeSO4 and coking wastewater was a two-step process. At the first step, i.e., 0≤Fe:TCN≤1.0, the reaction mechanisms were dominated by the precipitation of FeS, the complexation of CN(-), and the coagulation of organic compounds. The COD of coking wastewater decreased from 3748.1 mg/L to 3450.2 mg/L, but BOD5:COD (B/C) was improved from 0.30 to 0.51. At the second step, i.e., 1.0cyanide compounds by ferrous ions was the dominating mechanism. The COD showed a continuous increase to 3542.2 mg/L (Fe:TCN=3.2) due to the accumulated ferrous ions in coking wastewater. Moreover, B/C decreased progressively to 0.35, which was attributed to the negative effects of excess ferrous ions on biodegradability. To improve coking wastewater's biodegradability, a minimum ferrous dosage is required to complete the first step reaction. However, the optimum ferrous dosage should be determined to control a safe residual TCN in coking wastewater for the further biological treatment. Copyright © 2015 Elsevier B.V. All rights reserved.

  8. Metallurgi for Ingeniører

    DEFF Research Database (Denmark)

    Pedersen, Jan

    Ny gennemarbejdet udgave af den klassiske "Metallurgi for Ingeniører", først skrevet af K. Offer Andersen i 1962......Ny gennemarbejdet udgave af den klassiske "Metallurgi for Ingeniører", først skrevet af K. Offer Andersen i 1962...

  9. Metallurgy: A compilation

    Science.gov (United States)

    1973-01-01

    A technology utilization program is presented for the dissemination of information on technological developments which have potential utility outside the aerospace and nuclear communities. Discussion is restricted to the effects of hydrogen on a variety of metal alloys, and the mechanical properties of some recently developed alloys. Hydrogen at both low and high pressure is shown to have adverse effects on alloys such as ultrahigh-strength steels, irradiated steels, columbium, inconel alloys, titanium alloys, and certain stainless steels. The mechanical and physical properties of a wide range of alloys, their performance at elevated temperatures, and some of the processes involved in their development are also considered.

  10. Copper alloys with improved properties: standard ingot metallurgy vs. powder metallurgy

    Directory of Open Access Journals (Sweden)

    Milan T. Jovanović

    2014-09-01

    Full Text Available Three copper-based alloys: two composites reinforced with Al2O3 particles and processed through powder metallurgy (P/M route, i.e. by internal oxidation (Cu-2.5Al composite and by mechanical alloying (Cu-4.7Al2O3 and Cu-0.4Cr-0.08Zr alloy produced by ingot metallurgy (vacuum melting and casting were the object of this investigation. Light microscope and scanning electron microscope (SEM equipped with electron X-ray spectrometer (EDS were used for microstructural characterization. Microhardness and electrical conductivity were also measured. Compared to composite materials, Cu-0.4Cr-0.08Zr alloy possesses highest electrical conductivity in the range from 20 to 800 ℃, whereas the lowest conductivity shows composite Cu-2.5Al processed by internal oxidation. In spite to somewhat lower electrical conductivity (probably due to inadequate density, Cu-2.5Al composite exhibits thermal stability enabling its application at much higher temperatures than materials processed by mechanical alloying or by vacuum melting and casting.

  11. Possibilities of Formation of Dioxins and Furans in Metallurgical Processes as well as Methods of their Reduction

    Directory of Open Access Journals (Sweden)

    Holtzer, M.

    2007-01-01

    Full Text Available The metallurgical industry, among others, generates various kinds of wastes: gaseous, dusts, wastes and sewage. Special attention of the European Union is directed towards the elimination or significant reduction of the gaseous-dust contamination emissions including the most hazardous compounds, such as dioxins and furans. In the article the sources of dioxins and furans in metallurgical industry are described along with the reduction methods of these pollutants. Particularly the activities recommended as the Best Available Techniques (BAT in order to reduce the PCDD/PCDF emission from sintering processes, non-ferrous metallurgy and foundry engineering have been presented.

  12. Milling and Drilling Evaluation of Stainless Steel Powder Metallurgy Alloys

    Energy Technology Data Exchange (ETDEWEB)

    Lazarus, L.J.

    2001-12-10

    Near-net-shape components can be made with powder metallurgy (PM) processes. Only secondary operations such as milling and drilling are required to complete these components. In the past and currently production components are made from powder metallurgy (PM) stainless steel alloys. process engineers are unfamiliar with the difference in machining properties of wrought versus PM alloys and have had to make parts to develop the machining parameters. Design engineers are not generally aware that some PM alloy variations can be furnished with machining additives that greatly increase tool life. Specimens from a MANTEC PM alloy property study were made available. This study was undertaken to determine the machining properties of a number of stainless steel wrought and PM alloys under the same conditions so that comparisons of their machining properties could be made and relative tool life determined.

  13. Promoting energy conservation in China's metallurgy industry

    International Nuclear Information System (INIS)

    Lin, Boqiang; Du, Zhili

    2017-01-01

    China is undergoing rapid industrialization and urbanization, with consequent dramatic increase in energy demand. Given energy scarcity, environmental pollution, energy security and energy cost constraints, energy conservation will be the major strategy in China's transition to a low-carbon economy. Since the metallurgy industry is a main sector of energy consumption, the efficiency of energy conservation in this industry will affect the future prospects of energy savings. This paper analyzes the energy conservation potential of China's metallurgy industry. First, seemingly unrelated regression method is applied to investigate the relationship between energy relative price, R&D input, enterprise ownership structure, enterprise scale and energy intensity of the metallurgy industry. Then, based on the SUR results, we use the scenario analysis method to predict energy consumption and savings potential in the industry in different scenarios. This paper provides references for China's government and metallurgy industry in formulating relevant energy conservation policies. - Highlights: • Seemingly unrelated regression method is applied to analyze the energy intensity of metallurgy industry. • We use the scenario analysis method to predict energy consuming and energy saving of Chinese metallurgy industry. • Provide references for China's government and metallurgy industry in formulating relevant energy conservation policies.

  14. The metallurgy, science and engineering

    International Nuclear Information System (INIS)

    Pineau, A.; Quere, Y.

    2011-01-01

    Metallurgy, the science of metals and the technical discipline concerned with the production, shaping and assembling of metals, is one of the major assets of European economy. The French metallurgy industry - from producers (steel, light alloys, ...) to users (car, aviation, nuclear industries, ...) -- has achieved in many of its sectors a world-class level of excellence, based on high-quality research centres that are recognized both for their theoretical and experimental academic work. By contrast, public research is insufficiently concerned with engineering. In 2004, this industry employed 1 800 000 persons, 220 000 of which worked as engineers and managers in 45 000 companies, with a turnover of 420 billion euros. This state of grace is starting to decline. We are undergoing, in this sector as in others, a de-industrialization that affects upstream activities: courses in these disciplines, which have been previously outstanding, have partially disappeared; laboratories have shrunk; expertise has been dispersed; students are staying away from a discipline they consider 'unfruitful', like many other engineering sciences. Simultaneously, further up in this sector, decision centres have moved away from production centres and away from our country. France still maintains a few important R and D centres within international groups in spite of France's decreasing weight in world production. However, these groups see the future of R and D as being centred in the emerging countries (China, India...). The main users (transport, energy, ...) are losing their experts as are the technical centres on which rely a large network of small and medium businesses. The consequences are alarming in view of the already noticeable loss of technical control. This trend can and must be reversed. Because of its presence in many industrial sectors and its excellence, metallurgy - including both research and industry - is an essential activity in which France should remain a major player

  15. Powder metallurgy techniques in nuclear technology

    International Nuclear Information System (INIS)

    Mardon, P.G.

    1983-01-01

    The nuclear application of conventional powder metallurgy routes is centred on the fabrication of ceramic fuels. The stringent demands in terms of product performance required by the nuclear industry militate against the use of conventional powder metallurgy to produce metallic components such as the fuel cladding. However, the techniques developed in powder metallurgy find widespread application throughout nuclear technology. Illustrations of the use of these techniques are given in the fields of absorber materials, ceramic cladding materials, oxide fuels, cermet fuels, and the disposal of highly active waste. (author)

  16. Progress report of the Metallurgy Group

    International Nuclear Information System (INIS)

    Sundaram, C.V.; Moorthy, V.K.

    1975-01-01

    The activities of the Metallurgy Division of the Bhabha Atomic Research Centre, Bombay, during the year 1974 are reported under six sections, namely: ore dressing; extractive metallurgy; ceramics; physical metallurgy; corrosion and electrometallurgy, and radiometallurgy. The developmental programme is not only concerned with materials of nuclear interest such as uranium, thorium, plutonium, zirconium, niobium and beryllium, but also other materials of national interest such as titanium, tantalum, ceramics, corrosion-resistant alloys etc. In addition to the laboratory studies, collaborative work has also been undertaken with other units of the Department of Atomic Energy. (A.K.)

  17. Preparation of Magnetite Nanocrystals from Ferrous Sulphate Solution

    International Nuclear Information System (INIS)

    Cho Yu Mon; Tint Tint Kywe; Moe Moe Kyaw

    2010-12-01

    Magnetite (Fe3O4) nanoparticle were prepared by hydrothermal process in two ways, which would be used for production of copier toner.In this investigation, the first process was made from ferrous sulphate (FeSO4 . 7H2O) by using 10 M sodium hydroxide solution. In this method, magnetite nanoparticles were prepared by changing aeration time from 1 to 3 hr and heated at 90C for 15 min. The alternative process was carried out from ferrous sulphate (FeSO4.7H2O) by using 6.6 M sodium hydroxide solution and sodium silicate solution.Magnetite (black iron oxide) was synthesized by using different aeration times and reaction times. Aeration time was changed from 1 to 2 hr and reaction time was changed from 1 to 5.5 hr at 85 C. The magnetites obtained were examined by X-ray Diffraction (XRD) analysis and Scanning Electron Microscopy (SEM) technique. The average particle size range of magnetite nanoprticles were 90-120 nm and 120-150 nm in each process. The maximum yied percentages of magnetite based on FeSO4 in both processing were found to be 46.30% and 60.72%. The precent yields of magnetite in both preparation based on theoretical yields were 91.02% and 94.83% respectively.

  18. Near net shape of powder metallurgy rhenium parts

    International Nuclear Information System (INIS)

    Leonhardt, T.; Downs, J.

    2001-01-01

    In this paper, a description of the stages of processing necessary to produce a near-net shape (NNS) powder metallurgy (PM) rhenium component through the use of cold isostatic pressing (CIP) to form a complex shape will be explained. This method was primarily developed for the production of the 440 N and 490 N liquid apogee engine combustion chambers used in satellite positioning systems. The CIP to NNS process has been used in the manufacture and production of other rhenium aerospace components as well. Cold isostatic pressing (CIP) to a near net shape utilizing a one or two-part mandrel greatly reduces the quantity of rhenium required to produce the component, and also significantly reduces the number of secondary machining operations necessary to complete the manufacturing process. Further, the developments in near-net shape powder metallurgy rhenium manufacturing techniques have generated significant savings in the area of both time and budget. Overall, cost declined by as much as 35 % for the quantity of rhenium chambers, and manufacturing time was decreased by 30-40 %. The quantity of rhenium metal powder used to produce a rhenium chamber was reduced by approximately 70 %, with a subsequent reduction of nearly 50 % in secondary machining operation schedules. Thus, it is apparent that the overall savings provided by the production of near-net shape powder metallurgy rhenium components will be more than merely another aspect of any project involving high temperature applications, it will constitute significant benefit. (author)

  19. Effect of calcium oxide on the efficiency of ferrous ion oxidation and total iron precipitation during ferrous ion oxidation in simulated acid mine drainage treatment with inoculation of Acidithiobacillus ferrooxidans.

    Science.gov (United States)

    Liu, Fenwu; Zhou, Jun; Jin, Tongjun; Zhang, Shasha; Liu, Lanlan

    2016-01-01

    Calcium oxide was added into ferrous ion oxidation system in the presence of Acidithiobacillus ferrooxidans at concentrations of 0-4.00 g/L. The pH, ferrous ion oxidation efficiency, total iron precipitation efficiency, and phase of the solid minerals harvested from different treatments were investigated during the ferrous ion oxidation process. In control check (CK) system, pH of the solution decreased from 2.81 to 2.25 when ferrous ions achieved complete oxidation after 72 h of Acidithiobacillus ferrooxidans incubation without the addition of calcium oxide, and total iron precipitation efficiency reached 20.2%. Efficiency of ferrous ion oxidation and total iron precipitation was significantly improved when the amount of calcium oxide added was ≤1.33 g/L, and the minerals harvested from systems were mainly a mixture of jarosite and schwertmannite. For example, the ferrous ion oxidation efficiency reached 100% at 60 h and total iron precipitation efficiency was increased to 32.1% at 72 h when 1.33 g/L of calcium oxide was added. However, ferrous ion oxidation and total iron precipitation for jarosite and schwertmannite formation were inhibited if the amount of calcium oxide added was above 2.67 g/L, and large amounts of calcium sulfate dihydrate were generated in systems.

  20. The metallurgy of alloy 800

    International Nuclear Information System (INIS)

    Stone, P.G.; Orr, J.; Guest, J.C.

    1975-01-01

    Following a review of published information on the metallurgy of the iron/chromium/nickel system, attention is directed to the metallurgical significance of relatively minor compositional variations introduced in Alloy 800 to meet the stress corrosion requirements of the nuclear power industry. These include the effect of carbon, nitrogen, titanium, and aluminium restrictions in the context of Light Water Reactor, High Temperature Reactor, and Fast Reactor applications. Solubility effects are also considered in relation to heat treatment procedures, metallurgical phenomena, and associated properties. The aging behaviour is also discussed and related to fabrication and service performance; particularly stress rupture behaviour. The effect of strain at ambient and elevated temperatures on these aspects is indicated. (author)

  1. A major advance in powder metallurgy

    Science.gov (United States)

    Williams, Brian E.; Stiglich, Jacob J., Jr.; Kaplan, Richard B.; Tuffias, Robert H.

    1991-01-01

    Ultramet has developed a process which promises to significantly increase the mechanical properties of powder metallurgy (PM) parts. Current PM technology uses mixed powders of various constituents prior to compaction. The homogeneity and flaw distribution in PM parts depends on the uniformity of mixing and the maintenance of uniformity during compaction. Conventional PM fabrication processes typically result in non-uniform distribution of the matrix, flaw generation due to particle-particle contact when one of the constituents is a brittle material, and grain growth caused by high temperature, long duration compaction processes. Additionally, a significant amount of matrix material is usually necessary to fill voids and create 100 percent dense parts. In Ultramet's process, each individual particle is coated with the matrix material, and compaction is performed by solid state processing. In this program, Ultramet coated 12-micron tungsten particles with approximately 5 wt percent nickel/iron. After compaction, flexure strengths were measured 50 percent higher than those achieved in conventional liquid phase sintered parts (10 wt percent Ni/Fe). Further results and other material combinations are discussed.

  2. Nuclear science and metallurgy. Advances and interactions

    International Nuclear Information System (INIS)

    Grison, Emmanuel

    1977-01-01

    The history of the production of atomic power by fission since 1953 is reviewed: metallurgy of uranium; the new metals zirconium and beryllium; steels and nuclear structure; nuclear reactor vessels; water corrosion; effects of radiations [fr

  3. Nuclear science and metallurgy. Advances and interactions

    Energy Technology Data Exchange (ETDEWEB)

    Grison, E [CEA Centre d' Etudes Nucleaires de Saclay, 91 - Gif-sur-Yvette (France)

    1977-01-01

    The history of the production of atomic power by fission since 1953 is reviewed: metallurgy of uranium; the new metals zirconium and beryllium; steels and nuclear structure; nuclear reactor vessels; water corrosion; effects of radiations.

  4. [Respiratory diseases in metallurgy production workers].

    Science.gov (United States)

    Shliapnikov, D M; Vlasova, E M; Ponomareva, T A

    2012-01-01

    The authors identified features of respiratory diseases in workers of various metallurgy workshops. Cause-effect relationships are defined between occupational risk factors and respiratory diseases, with determining the affection level.

  5. Role of forgings in powder metallurgy industry

    International Nuclear Information System (INIS)

    Hayes, A.F.; DeRidder, A.J.

    1975-01-01

    Forging of powder metallurgy materials is discussed. Information and data are included on forging powder metallurgy W, Mo, In 100, Rene 95, Astroloy, Be, and Ti. It is noted that the combination of powder metallurgy and forging work provides the best product from standpoints of reproducibility, freedom from segregation, low scrap rate, and uniform mechanical properties. Experience is being used to develop contour forging from hot isostatic pressed billets or preforms. The quality of this product is under evaluation. Results show steady improvement and it is anticipated that continued effort will soon produce a reliable, less costly product. Forging can continue to be relied upon to correct subtle defects present in powder metallurgy material

  6. Aspects of the magnetism of ferrous chloride

    International Nuclear Information System (INIS)

    Carrara, P.

    1968-01-01

    This work is a critical review of the existing work on ferrous chloride and presents, as well, a number of new experimental results. First, a careful analysis of the level structure of ferrous ions in the crystalline field shows that the crystalline anisotropy is of the same order of magnitude as the exchange interactions, a feature which gives rise to some particular effects, such as an upward curvature of the magnetization curve at 0 K in a perpendicular magnetic field. Further, the very low temperature (T > 0.4 K) thermal variation of both the specific heat and magnetic susceptibility evidences a magnetic component in elementary excitations. This result suggests the presence of a large magneto-elastic coupling. Finally, an experimental study of the H-T phase diagram near T N and of the critical behaviour of the specific heat and parallel susceptibility was performed. (author) [fr

  7. Modern trends in increasing the quality of the steels intended for cutting and metal-working tools: I. Improvement of granule metallurgy processes

    Science.gov (United States)

    Belyanchikov, L. N.

    2008-12-01

    The following new technological processes for producing fine gas-atomized powders of tool and high-speed steels with a low content of nonmetallic inclusions are considered: the process designed by Böhler Uddeholm Powder Technology (Austria) and processes involving a heated gas. In the former process, a metal is poured from a ladle with electroslag heating, and the atomizing unit consists of three injectors. A new process of producing tools from fine powders by three-dimensional printing, i.e., so-called 3D-printing, is described.

  8. Diffusion measurement in ferrous infused gel dosimeters

    International Nuclear Information System (INIS)

    Zahmatkesh, M. H.; Healy, B. J.

    2003-01-01

    Background: The compositions of Ferrous sulphate, Agarose and Xylenol orange dye and Ferrous sulphate, Gelatin and Xylenol orange dye in solution of distilled water and sulphuric acid are two tissue-equivalent gel dosimeters. Ionizing radiation causes oxidation of Fe 2+ ion to Fe 3+ ions which diffuse through the gel matrix and blur the image of absorbed dose over a period of hours after irradiation. Materials and methods: 25 m M sulphuric acid, 0.4 mm ferrous ammonium sulphate, 0.2 mm xylenol orange dye and 1% by weight agarose in distilled water named Agarose and Xylenol orange dye and 0.1 mm ferrous ammonium sulphate, 0.1 mm xylenol orange dye, 50 mm sulphuric acid and 5% by weight gelatin in distilled water named Gelatin and Xylenol orange dye are used as two gel dosimeters. All chemicals were supplied by Sigma Ald ridge Company, Germany. The gels were poured in Perspex casts and were irradiated to a beam of X ray from linear accelerators or X ray machine. Results: In this study diffusion coefficients of Agarose and Xylenol orange dye and Gelatin and Xylenol orange dye dosimeters have been measured through a computer program for different temperature. The ferric ion diffusion coefficient (D) for the Agarose and Xylenol orange dye and Gelatin and Xylenol orange dye dosimeters were measured as (1.19.±0.03) x 10 -2 cm 2 .hr -1 and (0.83±0.03) x 10 -2 cm 2 .hr -1 respectively at room temperature. Conclusion: For both dosimeters the diffusion coefficients decreased with gel storage temperatures down to 6 d ig C . Gelatin and Xylenol orange dye dosimeters have advantage of lower diffusion coefficient for a specified temperature

  9. Passive Aerial Grasping of Ferrous Objects

    KAUST Repository

    Fiaz, Usman Amin

    2017-10-19

    Aerial transportation is probably the most efficient way to supply quick and effective aid especially in cases of emergency like search and rescue operations. Thus the ability to grasp and deliver objects is of vital importance in all sorts of unmanned and autonomous aerial operations. We detail a simple yet novel approach for aerial grasping of ferrous objects using a passive magnetic pickup and an impulse based drop mechanism. The design enables our gripper to grasp ferrous objects using single as well as multiple gripping pads, with visual as well as pickup and drop feedback. We describe the various components of the gripper with emphasis on its low mass and high lift capability since weight is a matter of high consideration in all aerial applications. In addition, we investigate and address the issues that may cause our design to fail. We demonstrate by experiments that the proposed design is robust and effective, based on its high payload capability, its sturdiness against possible slide during aggressive aerial maneuvers, and optimum performance of the drop mechanism for the designed range of payloads. We also show that the gripper is able to pick up and drop a single as well as multiple ferrous objects of different shapes, curvature, and inclination, which also involves picking up an object and then grasping the next, while keeping hold of the previous one.

  10. Passive Aerial Grasping of Ferrous Objects

    KAUST Repository

    Fiaz, Usman; Toumi, Noureddine; Shamma, Jeff S.

    2017-01-01

    Aerial transportation is probably the most efficient way to supply quick and effective aid especially in cases of emergency like search and rescue operations. Thus the ability to grasp and deliver objects is of vital importance in all sorts of unmanned and autonomous aerial operations. We detail a simple yet novel approach for aerial grasping of ferrous objects using a passive magnetic pickup and an impulse based drop mechanism. The design enables our gripper to grasp ferrous objects using single as well as multiple gripping pads, with visual as well as pickup and drop feedback. We describe the various components of the gripper with emphasis on its low mass and high lift capability since weight is a matter of high consideration in all aerial applications. In addition, we investigate and address the issues that may cause our design to fail. We demonstrate by experiments that the proposed design is robust and effective, based on its high payload capability, its sturdiness against possible slide during aggressive aerial maneuvers, and optimum performance of the drop mechanism for the designed range of payloads. We also show that the gripper is able to pick up and drop a single as well as multiple ferrous objects of different shapes, curvature, and inclination, which also involves picking up an object and then grasping the next, while keeping hold of the previous one.

  11. The ferrous ammonium sulfate solid system, as dosemeter for processes at low temperatures and high doses of gamma radiation; El sistema sulfato ferroso amoniacal solido, como dosimetro para procesos a bajas temperaturas y altas dosis de radiacion gamma

    Energy Technology Data Exchange (ETDEWEB)

    Juarez C, J.M.; Ramos B, S.; Negron M, A. [ICN-UNAM, 04510 Mexico D.F. (Mexico)

    2005-07-01

    This paper presents the results obtained from a study of the radiation induced oxidation of crystalline ferrous ammonium sulfate with gamma rays at 295 K, 263 K and 77 K and dose from 0 to 300 kGy. The radiation induced decomposition of ferrous ammonium sulfate has been studied by the dissolution of the irradiated salt in 0,8 N sulfuric acid. The main product is Fe{sup 3+} and molar concentration of ferric ion was determined spectrophotometrically in the UV region at 304 nm. The optical density values showed a linear dependence with dose, indicating that the data obtained might be used to create a calibrating curve. Color in irradiated salt changes from blue to green, yellow and orange according to the absorbed dose. The accuracy and the reproducibility of the system were tested. In addition, some other characteristics make possible the use of this system as a dosimeter, similar to Fricke chemical dosemeter, at low temperatures and high dose. (Author)

  12. Welding of a powder metallurgy uranium alloy

    International Nuclear Information System (INIS)

    Holbert, R.K.; Doughty, M.W.; Alexander-Morrison, G.M.

    1989-01-01

    The interest at the Oak Ridge Y-12 Plant in powder metallurgy (P/M) uranium parts is due to the potential cost savings in the fabrication of the material, to achieving a more homogeneous product, and to the reduction of uranium scrap. The joining of P/M uranium-6 wt-% niobium (U-6Nb) alloys by the electron beam (EB) welding process results in weld porosity. Varying the EB welding parameters did not eliminate the porosity. Reducing the oxygen and nitrogen content in this P/M uranium material did minimize the weld porosity, but this step made the techniques of producing the material more difficult. Therefore, joining wrought and P/M U-6Nb rods with the inertia welding technique is considered. Since no gases will be evolved with the solid-state welding process and the weld area will be compacted, porosity should not be a problem in the inertia welding of uranium alloys. The welds that are evaluated are wrought-to-wrought, wrought-to-P/M, and P/M-to-P/M U-6Nb samples

  13. Application of the ecologically clean technology of mining metallurgy and power industry wastes recycling based on the use of electron beams

    International Nuclear Information System (INIS)

    Mazhrenova, N.R.; Askarova, G.Sh.

    1997-01-01

    Advantage of electron beam technologies application for industrial wastes recycling is illustrated for following trends: 1).Off gases of mining metallurgy and the thermal power plant can be refined from SO 2 and NO x toxic combination by means of their further chemical and radiation oxidation with following obtaining of acids on the base industrial accelerator ELV-8. In this method a radiation-chemical process in irradiated gas results in excited complexes, radicals and ion formation. Ion cause the activation of reaction chain which convert SO 2 and NO x toxic gases into the combination with high number of oxidation. In presence of water, coming from drip cooler, the combination of sulphuric and nitric acids neutralization results in the obtaining of ammonium solid combination which are mainly sulphates and nitrates; 2). For waste water refinement from organic pollution, for instance butyl xanthate, ions of heavy metals and etc.; 3). For non-ferrous, sparse and and dispersed metal extraction from the cinder and slag wastes. Different technological schemes for mineral extraction are elaborated

  14. Magnetic Resonance Imaging Dosimetry application to chemical ferrous gels

    International Nuclear Information System (INIS)

    Calmet, Ch.

    2000-10-01

    MRI dosimetry is based on the determination of relaxation parameters (T1, T2). Chemical detectors whose NMR properties are sensitive to irradiation are used. Difficulties in absolute relaxation times measure limit the use of this technique. The aim of this work first consists in the development of a quantitative method to determine T, relaxation time on irradiated ferrous gels. So, we can study processes and parameters which affect the technique sensibility. The method sensitivity first depends on imaging instrumentation. Quantitative MRI method used is able to eliminate variable imager factors. The study of instrumental parameters (coil, sequence parameters) permits to define an imaging protocol which is a function of the considered application (volume size, spatial resolution and accuracy). The method sensitivity depends on the detector sensibility too. The best composition of ferrous gel has been determined. Dose distributions are obtained in three minutes. Comparison between MRI results and conventional dosimetry methods (specially ionisation chamber and films) shows a deviation of about 5% for single irradiation with energy fields in the range of 300 keV to 25 MeV. So, the proposed method forms a suitable technique for 3D dosimetry. (author)

  15. Mechanism of radiation and thermal decomposition of sulphide non-ferrous metals

    International Nuclear Information System (INIS)

    Mazhrenova, N.P.

    1998-01-01

    This paper deals with the non-ferrous metals sulfides in term of their radiative sensitivity, directed chances of their physical-chemical, and hence technological properties by radiation influence both on sulfide materials and on the processes with their participation. (author)

  16. Strength-Ductility Property Maps of Powder Metallurgy (PM) Ti-6Al-4V Alloy: A Critical Review of Processing-Structure-Property Relationships

    Science.gov (United States)

    Kumar, P.; Chandran, K. S. Ravi

    2017-05-01

    A comprehensive assessment of tensile properties of powder metallurgical (PM) processed Ti-6Al-4V alloy, through the mapping of strength-ductility property domains, is performed in this review. Tensile property data of PM Ti-6Al-4V alloys made from blended element (BE) and pre-alloyed powders including that additive manufactured (AM) from powders, as well as that made using titanium hydride powders, have been mapped in the form of strength-ductility domains. Based on this, porosity and microstructure have been identified as the dominant variables controlling both the strength and the tensile ductility of the final consolidated materials. The major finding is that tensile ductility of the PM titanium is most sensitive to the presence of pores. The significance of extreme-sized pores or defects in inducing large variations in ductility is emphasized. The tensile strength, however, has been found to depend only weakly on the porosity. The effect of microstructure on properties is masked by the variations in porosity and to some extent by the oxygen level. It is shown that any meaningful comparison of the microstructure can only be made under a constant porosity or density level. The beneficial effect of a refined microstructure is also brought out by logically organizing the data in terms of microstructure groups. The advantages of new processes, using titanium hydride powder to produce PM titanium alloys, in simultaneously increasing strength and ductility, are also highlighted. The tensile properties of AM Ti-6Al-4V alloys are also brought to light, in comparison with the other PM and wrought alloys, through the strength-ductility maps.

  17. Effect of process control agent on the porous structure and mechanical properties of a biomedical Ti-Sn-Nb alloy produced by powder metallurgy.

    Science.gov (United States)

    Nouri, A; Hodgson, P D; Wen, C E

    2010-04-01

    The influence of different amounts and types of process control agent (PCA), i.e., stearic acid and ethylene bis-stearamide, on the porous structure and mechanical properties of a biomedical Ti-16Sn-4Nb (wt.%) alloy was investigated. Alloy synthesis was performed on elemental metal powders using high-energy ball milling for 5h. Results indicated that varying the PCA content during ball milling led to a drastic change in morphology and particle-size distribution of the ball-milled powders. Porous titanium alloy samples sintered from the powders ball milled with the addition of various amounts of PCA also revealed different pore morphology and porosity. The Vickers hardness of the sintered titanium alloy samples exhibited a considerable increase with increasing PCA content. Moreover, the addition of larger amounts of PCA in the powder mixture resulted in a significant increase in the elastic modulus and peak stress for the sintered porous titanium alloy samples under compression. It should also be mentioned that the addition of PCA introduced contamination (mainly carbon and oxygen) into the sintered porous product. Crown Copyright 2009. Published by Elsevier Ltd. All rights reserved.

  18. Current programmes on physical metallurgy and related areas in BARC

    International Nuclear Information System (INIS)

    1994-01-01

    Current research and development programmes on physical metallurgy and related areas from the following Divisions of Bhabha Atomic Research Centre are included in this report : Atomic Fuels Division, High Pressure Physics Division, Metallurgy Division, Radio Metallurgy Division, Solid State Physics Division. Important publications corresponding to each activity have also been listed. (author)

  19. Ideate about building green mine of uranium mining and metallurgy

    International Nuclear Information System (INIS)

    Shi Zuyuan

    2012-01-01

    Analysing the current situation of uranium mining and metallurgy; Setting up goals for green uranium mining and metallurgy, its fundamental conditions, Contents and measures. Putting forward an idea to combine green uranium mining and metallurgy with the state target for green mining, and keeping its own characteristics. (author)

  20. Melting decontamination and recycling of radioactive polluted metals from uranium mining and metallurgy

    International Nuclear Information System (INIS)

    Chen Anquan

    2011-01-01

    Melting method is a primary method used for decontamination of radioactive polluted metal from uranium mining and metallurgy. The decontamination mechanism of the method, the way selection and its features are introduced. Taking the ten year's work of CNNC Uranium Mining and Metallurgy Radioactive Polluted Metal Melting Processing Center as example, the effects of processing radioactive polluted metals by smelting method are discussed. The surface pollution levels of radioactive polluted metal from uranium mining and metallurgy decreased from 4-48 Bq/cm 2 before decontamination to 0.004-0.016 Bq/cm 2 after decontamination, and the specific activity of its metal is less than 1 Bq/g, which is below the solution control level proposed by IAEARS-G1.7 'the application of the concepts of exclusion, immunity and solution control'. The metals after decontamination can be recycled by producing tooth plate and bucket teeth of excavator used in mines. (authors)

  1. Welding Metallurgy and Weldability of Stainless Steels

    Science.gov (United States)

    Lippold, John C.; Kotecki, Damian J.

    2005-03-01

    Welding Metallurgy and Weldability of Stainless Steels, the first book in over twenty years to address welding metallurgy and weldability issues associated with stainless steel, offers the most up-to-date and comprehensive treatment of these topics currently available. The authors emphasize fundamental metallurgical principles governing microstructure evolution and property development of stainless steels, including martensistic, ferric, austenitic, duplex, and precipitation hardening grades. They present a logical and well-organized look at the history, evolution, and primary uses of each stainless steel, including detailed descriptions of the associated weldability issues.

  2. Thermogravimetric control of intermediate compounds in uranium metallurgy; Control termogravimetrico de productos intermedios de la metalurgia del uranio

    Energy Technology Data Exchange (ETDEWEB)

    Gasco Sanchez, L; Fernandez Cellini, R

    1959-07-01

    The thermal decomposition of some intermediate compounds in the metallurgy of the uranium as uranium peroxide, ammonium uranate, uranium and ammonium penta-fluoride, uranium tetrafluoride and uranous oxide has been study by means of the Chevenard's thermo balance. Some data on pyrolysis of synthetic mixtures of intermediate compounds which may occasionally appear during the industrial process, are given. Thermogravimetric methods of control are suggested, usable in interesting products in the uranium metallurgy. (Author) 20 refs.

  3. Thermogravimetric control of intermediate compounds in uranium metallurgy; Control termogravimetrico de productos intermedios de la metalurgia del uranio

    Energy Technology Data Exchange (ETDEWEB)

    Gasco Sanchez, L.; Fernandez Cellini, R.

    1959-07-01

    The thermal decomposition of some intermediate compounds in the metallurgy of the uranium as uranium peroxide, ammonium uranate, uranium and ammonium penta-fluoride, uranium tetrafluoride and uranous oxide has been study by means of the Chevenard's thermo balance. Some data on pyrolysis of synthetic mixtures of intermediate compounds which may occasionally appear during the industrial process, are given. Thermogravimetric methods of control are suggested, usable in interesting products in the uranium metallurgy. (Author) 20 refs.

  4. Radiation effects in high-disperse metal media and their application in powder metallurgy

    International Nuclear Information System (INIS)

    Zaykin, Y.A.; Aliyev, B.A.

    2002-01-01

    Experimental and theoretical results showing up effects of metal powder radiation processing, such as powder grinding, chemical refinement, and changes in powder particle surface state, are discussed. It is shown that preliminary irradiation of metal powders leads to profound structural alterations at all further stages of their processing by conventional methods of powder metallurgy and eventually effects the properties of the resulting product

  5. Guangxi non-ferrous metal industry speeding up its restructuring

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    <正>Non-ferrous metal industry in Guangxi takes an important position in China.However,the waste of resources is severe due to its simple industrial structure,small size of enterprises, sloppy technology,scattered layout,obstructed market and indiscriminate mining.Starting from last year,Guangxi began the project of building a world-influential non-ferrous metal

  6. Biennial activity report of metallurgy programme for 1987 and 1988

    International Nuclear Information System (INIS)

    Shanmugam, V.; Rao, B.P.C.; Bhanu Sankara Rao, K.; Muralidharan, P.; Bhaduri, A.K.; Kuppusami, P.; Shyamsunder, M.T.; Sampath, N.; Sreedharan, O.M.

    1990-01-01

    The research and development (R and D) activities in the field of metallurgy at Indira Gandhi Centre for Atomic Research, Kalpakkam during 1987-1988 are reported in the form of individual summaries arranged under headings : (1) Mechanical Metallurgy Section, (2) Physical Metallurgy Section, (3) Chemical Metallurgy Section, (4) Materials Technology Section, (5) Division for PIE and NDT Development and (6) Quality Engineering Section. A list of publications by the staff scientists working in the field of metallurgy during report period is given in one of the appendices. (author). figs., tabs

  7. Metallurgy department publications and lectures 1987

    International Nuclear Information System (INIS)

    Schroeder Pedersen, A.; Bilde-Soerensen, J.B.

    1988-04-01

    A presentation (including abstract) of scientific and technical publications and lectures by the staff of the Metallurgy Department during 1987 is given. The list comprises journal papers, conference papers, reports, lectures and poster presentations in the following categories: Publications, Lectures and Poster Presentations. (author)

  8. Neutrons in the field of metallurgy

    International Nuclear Information System (INIS)

    Novion, C. de

    1989-01-01

    Beams of thermal neutrons are now widely used for the study of material structure. Following a summary of the characteristics of the neutron-material interaction, and an outlook on the major uses of neutrons in metallurgy, we present some examples of application. The comparative advantages and drawbacks of neutrons and X-rays are discussed. 14 refs [fr

  9. Development and prospect of china uranium mining and metallurgy

    International Nuclear Information System (INIS)

    Que Weimin; Wang Haifeng; Niu Yuqing; Gu Wancheng; Zhang Feifeng

    2007-01-01

    The development of industry of uranium mining and metallurgy in China has been reviewed generally, emphasizing on investigation approaches and application levels of uranium mining technologies such as in-situ leaching, heap leaching, stope leaching: on the basis of analysis on status of uranium mining and metallurgy and problems existed, also considering the specific features of deposit resources, the development orientation of uranium mining and metallurgy in China is pointed out. The industry of China uranium mining and metallurgy is faced to new opportunity of development and challenge in 21st century, the only way to realize sustainable development of uranium mining and metallurgy and harmonious development between economy and environment is to develop new technology on mining, ore beneficiation and metallurgy, increase the utilization level of uranium resources, low down impact on environment caused by mining and metallurgy. (authors)

  10. Fabrication by powder metallurgy of the niobium based alloy Nb-1-Zr

    International Nuclear Information System (INIS)

    Marty, M.; Delaunay, C.; Walder, A.

    1989-01-01

    The Nb-1Zr alloy has been produced by the powder metallurgy technique. Production of powders was performed by centrifugal atomization with the rotating electrode process (REP) under an inert atmosphere of argon-helium. Alloy powders were characterized by granulometric spectra, oxygen content and the various types of structures which were found. After consolidation by extrusion, materials were evaluated by tensile test under vacuum at ambient temperature, 750 and 900 0 C and compared with the same alloy elaborated by ingot metallurgy. 8 refs., 9 figs. (Author)

  11. Properties of powder metallurgy steel forgings

    International Nuclear Information System (INIS)

    Crowson, A.; Anderson, F.E.

    1977-01-01

    The effects of processing variables on the mechanical properties of heat-treated powder metallurgy (P/M) steel forgings were determined. Prealloyed 4600 steel powder blended with graphite to yield 4640 was compacted into preforms and hot forged in a warm, closed die. Variables studied were preform density, method of lubrication, preform sintering (time, temperature and atmosphere), forging pressure (20 and 40 tsi) and temperature (1850 0 F, 2000 0 F and 2200 0 F), and forging ratio (0.75 and 0.95). Relationships between interconnected porosity and total porosity for the various preform densities were determined. High density compacts required higher sintering temperatures due to the restricted mobility of the reducing gases in the pores. Die wall lubrication was comparable to admixed lubrication, and it simplified powder mixing and preform sintering operations. Forgings with densities from 99 to 99.8 percent of theoretical density were attained with a forging pressure of 20 to 40 tsi and preform temperatures of 2000 0 F and above. At forging conditions which resulted in forgings with acceptable mechanical properties, complete die fill was accomplished at a forging ratio of 0.95, whereas incomplete die fill resulted at a forging ratio of 0.75. The response of P/M forgings to heat treatment was comparable to that for wrought materials, and the resultant tensile and yield strengths were equivalent to the strength values described for wrought 4640 steel in AMS specification 6317B. In addition, ductility and impact properties of P/M forgings with near theoretical density (99.5+ percent) were comparable to bar stock forgings

  12. Solvent Extraction of Copper: An Extractive Metallurgy Exercise for Undergraduate Teaching Laboratories

    Science.gov (United States)

    Smellie, Iain A.; Forgan, Ross S.; Brodie, Claire; Gavine, Jack S.; Harris, Leanne; Houston, Daniel; Hoyland, Andrew D.; McCaughan, Rory P.; Miller, Andrew J.; Wilson, Liam; Woodhall, Fiona M.

    2016-01-01

    A multidisciplinary experiment for advanced undergraduate students has been developed in the context of extractive metallurgy. The experiment serves as a model of an important modern industrial process that combines aspects of organic/inorganic synthesis and analysis. Students are tasked to prepare a salicylaldoxime ligand and samples of the…

  13. Powder metallurgy approaches to high temperature components for gas turbine engines

    Science.gov (United States)

    Probst, H. B.

    1974-01-01

    Research is reported for the tensile strength, ductility, and heat performance characterisitics of powder metallurgy (p/m) superalloys. Oxide dispersion strengthened alloys were also evaluated for their strength during thermal processing. The mechanical attributes evident in both p/m supperalloys and dispersion strengthened alloys are discussed in terms of research into their possible combination.

  14. Extractive metallurgy of zirconium--1945 to the present

    International Nuclear Information System (INIS)

    Franklin, D.G.; Adamson, R.B.

    1984-01-01

    Although the history of the reduction of zirconium dates from 1824 and the first ductile zirconium metal was produced in the laboratory in 1914, modern reduction practice was pioneered by the U.S. Bureau of Mines starting in 1945. This paper reviews the history of the extractive metallurgy of zirconium from the early work of W. J. Kroll and co-workers at the Bureau of Mines in Albany, Ore., through the commercial development of the production of reactor-grade zirconium metal which was spurred by the requirements of the Naval Reactor Program and the development of commercial nuclear power. Technical subjects covered include processes for opening the ore, zirconium-hafnium separation, chlorination of zirconium oxide, reduction processes, and electrowinning of zirconium metal. Proposed new processes and process modifications are reviewed

  15. Computational thermodynamics in electric current metallurgy

    DEFF Research Database (Denmark)

    Bhowmik, Arghya; Qin, R.S.

    2015-01-01

    . The method has been validated against the analytical solution of current distribution and experimental observation of microstructure evolution. It provides a basis for the design, prediction and implementation of the electric current metallurgy. The applicability of the theory is discussed in the derivations.......A priori derivation for the extra free energy caused by the passing electric current in metal is presented. The analytical expression and its discrete format in support of the numerical calculation of thermodynamics in electric current metallurgy have been developed. This enables the calculation...... of electric current distribution, current induced temperature distribution and free energy sequence of various phase transitions in multiphase materials. The work is particularly suitable for the study of magnetic materials that contain various magnetic phases. The latter has not been considered in literature...

  16. Metallurgy Department annual progress report for 1987

    International Nuclear Information System (INIS)

    Schroeder Pedersen, A.; Bilde-Soerensen, J.B.; Hansen, N.

    1988-05-01

    Selected activities of the Metallurgy Department at Risoe National Laboratory during 1987 are described. The work is presented in four chapters: Materials Science, Materials Engineering, Materials Technology and Energy Programmes. A survey is given of the Department's participation in international collaboration and of its activities within education and training. Furthermore, the main numbers illustrating the Departments's economy are given. Lists of staff members, visiting scientists, publications, lectures and poster presentations are included. 38 ills. (author)

  17. Metallurgy Department. Annual progress report for 1988

    International Nuclear Information System (INIS)

    Schroeder Pedersen, A.; Bilde-Soerensen, J.B.; Hansen, N.

    1989-05-01

    Selected activities of the Metallurgy Department at Risoe National Laboratory during 1988 are described. The work is presented in four chapters: Materials Science, Materials Engineering, Materials Technology and Energy Programmes. A survey is given of the Department's participation in international collaboration and of its activities within education and training. Furthermore, the main numbers illustrating the Department's economy are given. Lists of staff members, visiting scientists, publications, lectures and poster presentations are included. (author) 36 ills., 81 refs

  18. The Mechanical Metallurgy of Armour Steels

    Science.gov (United States)

    2016-10-01

    plate hardness in Figure 2(a) are a result of increased resistance to plastic flow in a ductile hole formation failure mechanism. Beyond a certain...their mechanical metallurgy, and ballistic performance is explained, where such performance is primarily determined by material strength, hardness and...high strain rate behaviour. Other important topics such as toughness; the adiabatic shear phenomenon; structural cracking; and dual hardness and

  19. Physical metallurgy and physics of solids

    International Nuclear Information System (INIS)

    Friedel, J.

    1997-01-01

    A historical review of the development of fundamental research at the Cea in the field of material science, is presented, beginning with the study of material issues for nuclear applications, such as the growth, the swelling (of uranium and its alloys) and the embrittlement of steels. Other researches led to the introduction of plutonium in uranium oxide, paving the way to MOX fuels, and the study of diffusion in fundamental metallurgy, hot plasticity especially the hexagonal metals) and steady state conditions under irradiation

  20. Metallurgy Department. Annual progress report for 1989

    International Nuclear Information System (INIS)

    Horsewell, A.; Hansen, N.

    1990-07-01

    Selected activities of the Metallurgy Department at Risoe National Laboratory during 1989 are described. The work is presented in three chapters: Materials Science, Materials Engineering and Materials Technology. A survey is given of the Department's participation in international collaboration and of its acitivities within eduation and training. Furthermore, the main figures outlining the funding and expenditure of the Department are given. Lists of staff members, visiting scientists, publicaltions, lectures and poster presentations are included. (author) 90 refs

  1. Metallurgy in the Czech Republic: a spatio-temporal view

    Directory of Open Access Journals (Sweden)

    J. Suchacek

    2017-01-01

    Full Text Available The objective of this paper is to introduce the stochastic input-output model of the impact of metallurgy sector on the Czech economy. Contrary to original input-output model, which is of deterministic nature, we reckon with interval estimates of the development of metallurgy sector. They help us to surpass deterministic impediments when analyzing and forecasting the possible developmental tendencies of metallurgy sector in various economies.

  2. Prerequisites and opportunities for repositioning of the Urals metallurgy within the Industry 4.0

    Directory of Open Access Journals (Sweden)

    O. A. Romanova

    2017-12-01

    Full Text Available The authors present the modern trends in the development of metallurgy, and classify the technological structure of metallurgical industry. The article contains specific features of the development of metallurgy in the conditions of industry formation. A special role in this process plays the pace of digitalization and robotization of the industry, the development of additive technologies, Internet of things. The authors substantiate the possibility of developing the metallurgy of the Middle Urals as a science-intensive, high-tech complex that meets the requirements of Industry 4.0. This possibility interrelates with its repositioning, one of the main tasks of which is the formation of new sales markets focused on high-tech consumer industries, as well as the preservation of traditional consumption sectors under conditions of increasing competition in the construction materials market. The authors underline the importance of international cooperation in the field of environmentally safe industrial development, with applying the best available technologies and innovative development in general. The authors propose a methodological approach for assessing the repositioning of the regional metallurgical complex. This approach is the consecutive implementation of the following stages: assessment of dynamics and the forecast of development of consumer steel products sector and its structure based on identified priority areas of technological development of metallurgy in the region; construction of a factor model describing the changes in parameters of the RMC repositioning process, and approximation of the characteristics of their nonlinear elements; building a mathematical model on the basis of neural network algorithms for assessing the process of repositioning the RMC, taking into account projected values of the RMK parameters in the process of repositioning and changing the structure of consumer markets for metal products; formation of a variable

  3. Environmental protection technologies and prospect for uranium mining and metallurgy in China

    International Nuclear Information System (INIS)

    Pan Yingjie

    2002-01-01

    Based on practices of production and environmental protection of China's uranium mining and metallurgy, control and protection of the three wastes in uranium mining and metallurgy are discussed. Prospects for environmental protection technologies of uranium mining and metallurgy is made

  4. Coke briquets for metallurgy based on a thermoreactive binder

    Energy Technology Data Exchange (ETDEWEB)

    Tjutjunnikov, J.B.; Florinskij, V.N.; Orechov, V.N.; Nefedov, P.J.; Sasmurin, V.I.; Kirenskij, V.N. (Khar' kovskii Inzhenerno-Ehkonomicheskii Institut (USSR))

    1992-02-01

    Describes a process for production of briquets for metallurgy with binder and coke fines or anthracite. The suggested binder is waste phenol resin from the production of phenol (cumene method). Resin properties are given. Possible reaction mechanisms yielding solidified matter are discussed. The production process requires 10-15% binder and applies charge heating up to 200 C over 30 min. Catalytic amounts of sodium hydroxide or sulfuric acid were also employed. The production process is shown in a flowsheet. Properties of produced briquets are tabulated. The briquets were used in a 8 t/h cupola furnace and their performance was compared to that of KL-1 coke. Performance was found to be comparable; the cost of coke briquets was less than that of heating coke. 2 refs.

  5. [Ferrous sulfate in the treatment of iron deficiency anemia: The positions continue].

    Science.gov (United States)

    Dvoretsky, L I

    The paper discusses treatment strategy and tactics for iron deficiency anemia. It gives data on the comparative efficacy of different iron sulfate drugs, their bioavailability, effects on peroxidation processes, and side effects. The paper also considers the clinical significance of a dosage form of iron-containing drugs with a sustained iron release, as well as ways to reduce the frequency and magnitude of side effects when ferrous sulfate is used.

  6. Means to rise stability of matrices for hot pressing of non-ferrous metals

    International Nuclear Information System (INIS)

    Nagajtsev, A.A.; Piguzova, D.Kh.; Vajnpres, L.V.

    1975-01-01

    The paper deals with the basic trends adopted both in the USSR and abroad with respect to the development and industrial usage of new materials for hot pressing dies. Methods of their strengthening are also indicated. The paper presents results of production tests of new die steels and refractory alloys at a number of factories processing non-ferrous metals. The problems of their wide application in this field are considered

  7. Recent trends in extractive metallurgy

    Directory of Open Access Journals (Sweden)

    Habashi F.

    2009-01-01

    Full Text Available While pyrometallurgical processes are old technology and were the dominant and logical route used to treat sulfide concentrates they are now challenged by new hydrometallurgical processes. In these new processes there have been attempts in the past few years to avoid using autoclaves in the treatment of concentrates of zinc, copper, and nickel. The situation has been recently reversed and pressure hydrometallurgy is being applied in many operations. An outline of these processes is given and the future trend is discussed.

  8. Annual report of the Metallurgy Division [for the] period ending December 1977

    International Nuclear Information System (INIS)

    Elayaperumal, K.; Sridhar Rao, Ch.; Mukhopadhyay, P.; Rao, S.V.K.

    1979-01-01

    The research and development work carried out and the various programmes underway in the Metallurgy Division of the Bhabha Atomic Research Centre, Bombay, during the calendar year 1977 have been reported. The R and D work and programmes cover extraction metallurgy, physical metallurgy, alloy development, corrosion metallurgy and ceramics. Some of the major studies and programmes are: (1) development of processes for extraction of niobium, vanadium, hafnium and nickel, (2) preparation of niobium alloys, ferro-zirconium, ceramic grade zirconia, (3) electro-refining of zircaloy scrap, (4) preparation of anhydrous beryllium fluoride from Indian beryl, (5) preparation of beryllium alloys, (6) studies on phase transformation and deformation behaviour of zirconium and zirconium-oxygen alloys, (7) self-diffusion studies in dilute Zr-Fe and Zr-Cr alloys, (8) studies on corrosion and stress corrosion cracking of zirconium base alloys and (9) sintering studies on ZrO 2 -PuO 2 and BeO. (M.G.B.)

  9. N18, powder metallurgy superalloy for disks: Development and applications

    Energy Technology Data Exchange (ETDEWEB)

    Guedou, J.Y.; Lautridou, J.C.; Honnorat, Y. (SNECMA, Evry (France). Materials and Processes Dept.)

    1993-08-01

    The preliminary industrial development of a powder metallurgy (PM) superalloy, designated N18, for disk applications has been completed. This alloy exhibits good overall mechanical properties after appropriate processing of the material. These properties have been measured on both isothermally forged and extruded billets, as well as on specimens cut from actual parts. The temperature capability of the alloy is about 700 C for long-term applications and approximately 750 C for short-term use because of microstructural instability. Further improvements in creep and crack propagation properties, without significant reduction in tensile strength, are possible through appropriate thermomechanical processing, which results in a large controlled grain size. Spin pit tests on subscale disks have confirmed that the N18 alloy has a higher resistance than PM Astrology and is therefore an excellent alloy for modern turbine disk applications.

  10. Advanced powder metallurgy aluminum alloys via rapid solidification technology

    Science.gov (United States)

    Ray, R.

    1984-01-01

    Aluminum alloys containing 10 to 11.5 wt. pct. of iron and 1.5 to 3 wt. pct. of chromium using the technique of rapid solidification powder metallurgy were studied. Alloys were prepared as thin ribbons (.002 inch thick) rapidly solidified at uniform rate of 10(6) C/second by the melt spinning process. The melt spun ribbons were pulverized into powders (-60 to 400 mesh) by a rotating hammer mill. The powders were consolidated by hot extrusion at a high reduction ratio of 50:1. The powder extrusion temperature was varied to determine the range of desirable processing conditions necessary to yield useful properties. Powders and consolidated alloys were characterized by SEM and optical metallography. The consolidated alloys were evaluated for (1) thermal stability, (2) tensile properties in the range, room temperature to 450 F, and (3) notch toughness in the range, room temperature to 450 F.

  11. Metafusion: A breakthrough in metallurgy

    Science.gov (United States)

    Joseph, Adrian A.

    1994-01-01

    The Metafuse Process is a patented development in the field of thin film coatings utilizing cold fusion which results in a true inter-dispersion of dissimilar materials along a gradual transition gradient through a boundary of several hundred atomic layers. The process is performed at ambient temperatures and pressures requiring relatively little energy and creating little or no heat. The process permits a remarkable range of material combinations and joining of materials which are normally incompatible. Initial applications include titanium carbide into and onto the copper resistance welding electrodes and tungsten carbide onto the cutting edges of tool steel blades. The process is achieved through application of an RF signal of low power and is based on the theory of vacancy fusion.

  12. New trends for non-ferrous metals in the electrical engineering industry

    International Nuclear Information System (INIS)

    Singer, R.F.

    1989-01-01

    The non-ferrous metals copper, aluminium and nickel are of major importance to the electrical engineering industry. Copper is used for magnet wire, underground cable and overhead contact wire, and aluminium is important for overhead power transmission lines. Nickel alloys are employed as gas turbine blades in power generation. An important new trend in the conductor area is rapid solidification for improved combinations of strength and conductivity. Another new trend is the Conform continuous extrusion process which can decrease cost and increase quality. New high temperature superconductors might change the conductor market completely, but only on the long run. Nickel base blading materials will see considerable improvements from oxide dispersion strengthening and directional solidification. In summary, non-ferrous materials technology for electrical engineering applications is on the move and considerable improvements can be expected within the next decade. (orig.) [de

  13. Study on the formation of cubic texture in Ni-7 at.% W alloy substrates by powder metallurgy routes

    DEFF Research Database (Denmark)

    Zhao, Yue; Suo, HongLi; Zhu, YongHua

    2009-01-01

    One of the main challenges for coated conductor applications is to produce sharp cubic textured alloy substrates with high strength and low magnetism. In this work, the cubic textured Ni–7 at.% W substrates were prepared from different powder metallurgy ingots by rolling-assisted biaxially textured...... substrate processing. The fabrication processes of cubic texture in the Ni–7 at.% W tapes by two powder metallurgy routes are described in detail. Through the optimized process, full width at half maximum values of 6.7° and 5.0° were obtained, as estimated by X-ray (1 1 1) phi scan and (2 0 0) rocking curve...

  14. Ceramic Inclusions In Powder Metallurgy Disk Alloys: Characterization and Modeling

    Science.gov (United States)

    Bonacuse, Pete; Kantzos, Pete; Telesman, Jack

    2002-01-01

    Powder metallurgy alloys are increasingly used in gas turbine engines, especially as the material chosen for turbine disks. Although powder metallurgy materials have many advantages over conventionally cast and wrought alloys (higher strength, higher temperature capability, etc.), they suffer from the rare occurrence of ceramic defects (inclusions) that arise from the powder atomization process. These inclusions can have potentially large detrimental effect on the durability of individual components. An inclusion in a high stress location can act as a site for premature crack initiation and thereby considerably reduce the fatigue life. Because these inclusions are exceedingly rare, they usually don't reveal themselves in the process of characterizing the material for a particular application (the cumulative volume of the test bars in a fatigue life characterization is typically on the order of a single actual component). Ceramic inclusions have, however, been found to be the root cause of a number of catastrophic engine failures. To investigate the effect of these inclusions in detail, we have undertaken a study where a known population of ceramic particles, whose composition and morphology are designed to mimic the 'natural' inclusions, are added to the precursor powder. Surface connected inclusions have been found to have a particularly large detrimental effect on fatigue life, therefore the volume of ceramic 'seeds' added is calculated to ensure that a minimum number will occur on the surface of the fatigue test bars. Because the ceramic inclusions are irregularly shaped and have a tendency to break up in the process of extrusion and forging, a method of calculating the probability of occurrence and expected intercepted surface and embedded cross-sectional areas were needed. We have developed a Monte Carlo simulation to determine the distributions of these parameters and have verified the simulated results with observations of ceramic inclusions found in macro

  15. Metallurgy and Heat Treating. Welding Module 7. Instructor's Guide.

    Science.gov (United States)

    Missouri Univ., Columbia. Instructional Materials Lab.

    This guide is intended to assist vocational educators in teaching a three-unit module in metallurgy and heat treating. The module is part of a welding curriculum that has been designed to be totally integrated with Missouri's Vocational Instruction Management System. The basic principles of metallurgy and heat treatment and techniques for…

  16. Borax as a lubricant in powder metallurgy

    Directory of Open Access Journals (Sweden)

    Héctor Geovanny Ariza-Suarez

    2014-12-01

    were compacted at 700 MPa in a uniaxial press of 15 tons. DSC-TGA analysis of the mixture with borax was realized. The specimens were sintered in a plasma reactor at 1000 for 30 minutes, with a combined atmosphere of hydrogen and argon. Microhardness and density of the sintered samples was haracterized. XRD analysis was realized to detect possible compounds formation by interaction of borax. This paper shows that borax can be used as a lubricant in powder metallurgy.

  17. Metallurgy and purification of semiconductor materials

    International Nuclear Information System (INIS)

    Mughal, G.R.; Ali, M.M.; Ali, I.

    1996-01-01

    In this article the metallurgical aspects of semiconductor science and technology have been stressed here rather than of the physical and electronic aspect of the subject. Semiconductor technology has not merely presented the metallurgist with new challenges. The ease with which the semiconductor planes cleave make possible, the preparation and study of virgin surface. Semiconductor materials were being widely employed in the study of sub-boundaries and structures and can largely contribute to the study of certain aspects of nucleation and growth, precipitation phenomena, mechanical behaviour, in metallurgy. (A.B.)

  18. Biaxially textured articles formed by powder metallurgy

    Science.gov (United States)

    Goyal, Amit; Williams, Robert K.; Kroeger, Donald M.

    2003-08-05

    A biaxially textured alloy article having a magnetism less than pure Ni includes a rolled and annealed compacted and sintered powder-metallurgy preform article, the preform article having been formed from a powder mixture selected from the group of ternary mixtures consisting of: Ni powder, Cu powder, and Al powder, Ni powder, Cr powder, and Al powder; Ni powder, W powder and Al powder; Ni powder, V powder, and Al powder; Ni powder, Mo powder, and Al powder; the article having a fine and homogeneous grain structure; and having a dominant cube oriented {100} orientation texture; and further having a Curie temperature less than that of pure Ni.

  19. Low-Cobalt Powder-Metallurgy Superalloy

    Science.gov (United States)

    Harf, F. H.

    1986-01-01

    Highly-stressed jet-engine parts made with less cobalt. Udimet 700* (or equivalent) is common nickel-based superalloy used in hot sections of jet engines for many years. This alloy, while normally used in wrought condition, also gas-atomized into prealloyed powder-metallurgy (PM) product. Product can be consolidated by hot isostatically pressing (HIPPM condition) and formed into parts such as turbine disk. Such jet-engine disks "see" both high stresses and temperatures to 1,400 degrees F (760 degrees C).

  20. Biaxially textured articles formed by powder metallurgy

    Science.gov (United States)

    Goyal, Amit; Williams, Robert K.; Kroeger, Donald M.

    2003-07-29

    A biaxially textured alloy article having a magnetism less than pure Ni includes a rolled and annealed compacted and sintered powder-metallurgy preform article, the preform article having been formed from a powder mixture selected from the group of mixtures consisting of: at least 60 at % Ni powder and at least one of Cr powder, W powder, V powder, Mo powder, Cu powder, Al powder, Ce powder, YSZ powder, Y powder, Mg powder, and RE powder; the article having a fine and homogeneous grain structure; and having a dominant cube oriented {100} orientation texture; and further having a Curie temperature less than that of pure Ni.

  1. Biaxially textured articles formed by power metallurgy

    Science.gov (United States)

    Goyal, Amit; Williams, Robert K.; Kroeger, Donald M.

    2003-08-26

    A biaxially textured alloy article having a magnetism less than pure Ni includes a rolled and annealed compacted and sintered powder-metallurgy preform article, the preform article having been formed from a powder mixture selected from the group of mixtures consisting of: at least 60 at % Ni powder and at least one of Cr powder, W powder, V powder, Mo powder, Cu powder, Al powder, Ce powder, YSZ powder, Y powder, Mg powder, and RE powder; the article having a fine and homogeneous grain structure; and having a dominant cube oriented {100} orientation texture; and further having a Curie temperature less than that of pure Ni.

  2. Stress analyses of pump gears produced by powder metallurgy

    Energy Technology Data Exchange (ETDEWEB)

    Cetinel, Hakan [Celal Bayar Univ., Mechanical Engineering Dept. (Turkey); Yilmaz, Burak

    2013-06-01

    In this study, trochoidal type (gerotor) hydraulic pump gears were produced by powder metallurgy (P/M) technique. Several gears with different mechanical properties have been obtained by changing process variables. The tooth contact stresses were calculated analytically under particular operation conditions of the hydraulic pump. The 3D models have been obtained from real gears by using Capability Maturity Model (CMM, 3D scanning) operation and SOLIDWORKS software. Stress analyses were conducted on these 3D models by using ANSYS WORKBENCH software. It was found that the density increases by the increase of sintering duration and mechanical properties were positively affected by the increase of density. Maximum deformation takes place in the region of the outer gear where failure generally occurs with the minimum cross-section area.

  3. Radiometric measurement techniques in metallurgy and foundry technology

    International Nuclear Information System (INIS)

    1990-01-01

    The contributions contain informations concerning the present state and development of radiometric measurement techniques in metallurgy and foundry technology as well as their application to the solution of various problems. The development of isotope techniques is briefly described. Major applications of radiometric equipment in industrial measurement are presented together with the use of isotopes to monitor processes of industrial production. This is followed by a short description of numerous laboratory-scale applications. Another contribution deals with fundamental problems and methods of moisture measurement by neutrons. A complex moisture/density measurement device the practical applicability of which has been tested is described here. Possibilities for clay determination in used-up moulding materials are discussed in a further contribution. The clay content can be determined by real-time radiometric density measurement so that the necessary moisture or addition of fresh sand can be controlled. (orig.) With 20 figs., 9 tabs., 178 refs [de

  4. Technetium behavior in sulfide and ferrous iron solutions

    International Nuclear Information System (INIS)

    Lee, S.Y.; Bondietti, E.A.

    1982-01-01

    Pertechnetate oxyanion ( 99 TcO 4- ), a potentially mobile species in leachate from a breached radioactive waste repository, was removed from a brine solution by precipitation with sulfide, iron, and ferrous sulfide at environmental pH's. Maghemite (ν-Fe 2 O 3 ) and geothite (α-FeOOH) were the dominant minerals in the precipitate obtained from the TcO 4- -ferrous iron reaction. The observation of small particle size and poor crystallinity of the minerals formed in the presence of Tc suggested that the Tc was incorporated into the mineral structure after reduction to a lower valence state. Amorphous ferrous sulfide, an initial phase precipitating in the TcO 4- -ferrous iron-sulfide reaction, was transformed to goethite and hematite (α-Fe 2 O 3 ) on aging. The black precipitate obtained from the TcO 4- -sulfide reaction was poorly crystallized technetium sulfide (Tc 2 S 7 ) which was insoluble in both acid and alkaline solution in the absence of strong oxidents. The results suggested that ferrous- and/or sulfide-bearing groundwaters and minerals in host rocks or backfill barriers could reduce the mobility of Tc through the formation of less-soluble Tc-bearing iron and/or sulfide minerals

  5. Proceedings of the international symposium for research scholars on metallurgy, materials science and engineering

    International Nuclear Information System (INIS)

    2010-01-01

    Topics covered in this symposium are: steels, functional materials posters, computational materials science, casting and solidification, polymer matrix composites, posters electronic materials, environmental degradation processing of non-metallic materials posters, energy materials, materials forming technology, biomaterials, magnetic materials, mechanical behaviour of materials posters, phase transformations and physical metallurgy, surface engineering, nanostructured materials, ceramics, processing of metals, materials joining technology and optical materials. Papers relevant to INIS are indexed separately

  6. Possible Association of Ferrous Phosphates and Ferric Sulfates in S-rich Soil on Mars

    Science.gov (United States)

    Mao, J.; Schroeder, C.; Haderlein, S.

    2012-12-01

    NASA Mars Exploration Rover (MER) Spirit explored Gusev Crater to look for signs of ancient aqueous activity, assess past environmental conditions and suitability for life. Spirit excavated light-toned, S-rich soils at several locations. These are likely of hydrothermal, possibly fumarolic origin. At a location dubbed Paso Robles the light-toned soil was also rich in P - a signature from surrounding rock. While S is mainly bound in ferric hydrated sulfates [1], the mineralogy of P is ill-constrained [2]. P is a key element for life and its mineralogy constrains its availability. Ferrous phases observed in Paso Robles Mössbauer spectra may represent olivine and pyroxene from surrounding basaltic soil [1] or ferrous phosphate minerals [3]. Phosphate is well-known to complex and stabilize Fe 2+ against oxidation to Fe 3+ . Schröder et al. [3] proposed a formation pathway of ferrous phosphate/ferric sulfate associations: sulfuric acid reacts with basalt containing apatite, forming CaSO4 and phosphoric acid. The phosphoric and/or excess sulfuric acid reacts with olivine, forming Fe2+-phosphate and sulfate. The phosphate is less soluble and precipitates. Ferrous sulfate remains in solution and is oxidized as pH increases. To verify this pathway, we dissolved Fe2+-chloride and Na-phosphate salts in sulfuric acid inside an anoxic glovebox. The solution was titrated to pH 6 by adding NaOH when a first precipitate formed, which was ferrous phosphate according to Mössbauer spectroscopy (MB). At that point the solution was removed from the glovebox and allowed to evaporate in the presence of atmospheric oxygen, leading to the oxidation of Fe2+. The evaporation rate was controlled by keeping the suspensions at different temperatures; pH was monitored during the evaporation process. The final precipitates were analyzed by MB and X-Ray Fluorescence (XRF), comparable to MER MB and Alpha Particle X-ray Spectrometer instrument datasets, and complementary techniques such as X

  7. Study of the microstructural and mechanical properties of titanium-niobium-zirconium based alloys processed with hydrogen and powder metallurgy for use in dental implants; Estudo das propriedades mecanicas e microestruturais de ligas a base de titanio-niobiozirconio processados com hidrogenio e metalurgia do po para utilizacao em implantes dentarios

    Energy Technology Data Exchange (ETDEWEB)

    Duvaizem, Jose Helio

    2009-07-01

    Hydrogen has been used as pulverization agent in alloys based on rare earth and transition metals due to its extremely high diffusion rate even on low temperatures. Such materials are used on hydrogen storage dispositives, generation of electricity or magnetic fields, and are produced by a process which the first step is the transformation of the alloy in fine powder by miling. Besides those, hydrogenium is also being used to obtain alloys based on titanium - niobium - zirconium in the pulverization. Powder metallurgy is utilized on the production of these alloys, making it possible to obtain structures with porous surface as result, requirement for its application as biomaterials. Other advantages of powder metallurgy usage include better surface finish and better microstructural homogeneity. In this work samples were prepared in the Ti-13Nb-13Zr composition. The hydrogenation was performed at 700 degree C, 600 degree C, and 500 degree C for titanium, niobium and zirconium respectively. After hydrogenation, the milling stage was carried out on high energy planetary ball milling with 200rpm during 90 minutes, and also in conventional ball milling for 30 hours. Samples were pressed in uniaxial press, followed by isostatic cold press, and then sintered at 1150 degree C for 7-13 hours. Microstructural properties of the samples were characterized by scanning electron microscope (SEM), energy dispersive spectroscopy (EDS) and x-ray diffraction. Mechanical and structural properties determined were density, microhardness and moduli of elasticity. The sample sintered at 1150 degree C for 7h, hydrogenated using 10.000 mbar and produced by milling on high energy planetary ball milling presented the best mechanical properties and microstructural homogeneity. (author)

  8. Powder metallurgy development at SRL

    International Nuclear Information System (INIS)

    Peacock, H.B.

    1993-01-01

    The Savannah River Laboratory (SRL) is developing a powder metallury (P/M) process for manufacturing reactor-grade fuel tubes containing high wt % U 3 O 8 -Al cores clad with 8001 aluminum. The P/M cores are made by isostatic compaction. They are assembled in billets, outgassed, and hot-extruded using conventional coextrusion techniques. Cores have been compacted with up to 100% U 3 O 8 and tubes extruded with 80 wt % oxide cores. Irradiation tests have been made using P/M core tubes in the Savannah River reactors. These tubes contained U 3 O 8 concentrations up to 59 wt % and no significant swelling or blistering occurred. The tubes were irradiated to ∼40% burnup or 1.6x10 21 fissions/cc of core. This report discusses both small-scale and production tests for high- density P/M fuel development. The purpose of the P/M development program at SRL is to: (1) determine the maximum U 3 O 8 content that can be fabricated into thin wall tubes, (2) irradiate high-density tubes to high burnup and assess irradiation and dimensional stability, (3) continue metal forming studies for extrusion and drawing, and (4) evaluate hydrostatic extrusion and hydrostatically assisted drawing of P/M core tubes

  9. Metals in Past Societies: A Global Perspective on Indigenous African Metallurgy Shadreck Chirikure

    Energy Technology Data Exchange (ETDEWEB)

    Devanathan, Ram [Pacific Northwest National Lab. (PNNL), Richland, WA (United States)

    2015-10-01

    This slim book (166 pages) shines a spotlight on pre-industrial African metallurgy, its global connections, and anthropological implications. It integrates seemingly disparate disciplines, such as history, geology, ethnography, archeology, and metallurgy, to illustrate the diversity and innovation in metallurgy across Africa and the role of metals in the rise of socio-economic inequalities and political power. The book has 7 chapters and the focus on metals as enablers of human needs and wants is evident in each chapter. The first chapter presents the context of the work and data sources. The second chapter focuses on the origin and development of mining and metallurgy in pre-industrial Africa. Chapter 3 is dedicated to the interaction of nature and culture in the process of mining. Chapter 4 deals with the transformation of the ore into metal by smelting and the sociocultural aspects of this process. Chapter 5 explores the social and cultural roles acquired by metals as a result of fabrication into objects. Chapter 6 examines the social role of metals, trade in metals, cultural contact, proto-globalization, and technology transfer. Finally, Chapter 7 draws lessons for global anthropology from the African experience. The sources of information are adequately cited and the long list of references at the end of each chapter will be a boon to researchers in this field. The author highlights the cultural aspects and social context of the adoption of metallurgy in Africa while drawing parallels between practices in pre-industrial Africa and those in other parts of the world. The book is peppered with delightful vignettes that offer insights into the process of transforming nature into culturally significant objects. For instance, African miners, like their counterparts in Nepal and Latin America, called upon deities, spirits and ancestors to mediate between nature and humans. Women had distinct roles in this process, but there were variations in these roles and in the

  10. Copper metallurgy at the crossroads

    Directory of Open Access Journals (Sweden)

    Habashi F.

    2007-01-01

    Full Text Available Copper technology changed from the vertical to the horizontal furnace and from the roast reaction to converting towards the end of the last century. However, the horizontal furnace proved to be an inefficient and polluting reactor. As a result many attempts were made to replace it. In the past 50 years new successful melting processes were introduced on an industrial scale that were more energy efficient and less polluting. In addition, smelting and converting were conducted in a single reactor in which the concentrate was fed and the raw copper was produced. The standing problem in many countries, however, is marketing 3 tonnes of sulfuric acid per tonne of copper produced as well as emitting large amounts of excess SO2 in the atmosphere. Pressure hydrometallurgy offers the possibility of liberating the copper industry from SO2 problem. Heap leaching technology has become a gigantic operation. Combined with solvent extraction and electrowinning it contributes today to about 20% of copper production and is expected to grow. Pressure leaching offers the possibility of liberating the copper industry from SO2 problem. The technology is over hundred years old. It is applied for leaching a variety of ores and concentrates. Hydrothermal oxidation of sulfide concentrates has the enormous advantage of producing elemental sulfur, hence solving the SO2 and sulfuric acid problems found in smelters. Precipitation of metals such as nickel and cobalt under hydrothermal conditions has been used for over 50 years. It has the advantage of a compact plant but the disadvantage of producing ammonium sulfate as a co-product. In case of copper, however, precipitation takes place without the need of neutralizing the acid, which is a great advantage and could be an excellent substitute for electrowinning which is energy intensive and occupies extensive space. Recent advances in the engineering aspects of pressure equipment design open the door widely for increased

  11. Quantifying the properties of low-cost powder metallurgy titanium alloys

    International Nuclear Information System (INIS)

    Bolzoni, L.; Ruiz-Navas, E.M.; Gordo, E.

    2017-01-01

    The extensive industrial employment of titanium is hindered by its high production costs where reduction of these costs can be achieved using cheap alloying elements and appropriate alternative processing techniques. In this work the feasibility of the production of low-cost titanium alloys is addressed by adding steel to pure titanium and processing the alloys by powder metallurgy. In particular, a spherical 4140 LCH steel powder commonly used in metal injection moulding is blended with irregular hydride-dehydride Ti. The new low-cost alloys are cold uniaxially pressed and sintered under high vacuum and show comparable properties to other wrought-equivalent and powder metallurgy titanium alloys. Differential thermal analysis and X-ray diffraction analyses confirm that Ti can tolerate the employment of iron as primary alloying element without forming detrimental TiFe-based intermetallic phases. Thus, the newly designed α+β alloys could be used for cheaper non-critical components.

  12. Quantifying the properties of low-cost powder metallurgy titanium alloys

    Energy Technology Data Exchange (ETDEWEB)

    Bolzoni, L., E-mail: bolzoni.leandro@gmail.com [WaiCAM (Waikato Centre for Advanced Materials), The University of Waikato, Private Bag 3105, 3240 Hamilton (New Zealand); Ruiz-Navas, E.M.; Gordo, E. [Department of Materials Science and Engineering, University Carlos III of Madrid, Avda. de la Universidad, 30, 28911 Leganés, Madrid (Spain)

    2017-02-27

    The extensive industrial employment of titanium is hindered by its high production costs where reduction of these costs can be achieved using cheap alloying elements and appropriate alternative processing techniques. In this work the feasibility of the production of low-cost titanium alloys is addressed by adding steel to pure titanium and processing the alloys by powder metallurgy. In particular, a spherical 4140 LCH steel powder commonly used in metal injection moulding is blended with irregular hydride-dehydride Ti. The new low-cost alloys are cold uniaxially pressed and sintered under high vacuum and show comparable properties to other wrought-equivalent and powder metallurgy titanium alloys. Differential thermal analysis and X-ray diffraction analyses confirm that Ti can tolerate the employment of iron as primary alloying element without forming detrimental TiFe-based intermetallic phases. Thus, the newly designed α+β alloys could be used for cheaper non-critical components.

  13. Formalization of Technological Knowledge in the Field of Metallurgy using Document Classification Tools Supported with Semantic Techniques

    Directory of Open Access Journals (Sweden)

    Regulski K.

    2017-06-01

    Full Text Available The process of knowledge formalization is an essential part of decision support systems development. Creating a technological knowledge base in the field of metallurgy encountered problems in acquisition and codifying reusable computer artifacts based on text documents. The aim of the work was to adapt the algorithms for classification of documents and to develop a method of semantic integration of a created repository. Author used artificial intelligence tools: latent semantic indexing, rough sets, association rules learning and ontologies as a tool for integration. The developed methodology allowed for the creation of semantic knowledge base on the basis of documents in natural language in the field of metallurgy.

  14. Production of uranium in Navoi Mining and Metallurgy Combinat, Uzbekistan

    International Nuclear Information System (INIS)

    Kuchersky, N.; Tolstov, E.A.; Mazurkevich, A.P.; Inozemzev, S.B.

    2001-01-01

    Full text: Under the conditions of constantly increasing level of development of the nuclear power, it is inevitable that the uranium stockpiles accumulated to 1985 will soon be depleted. This consideration underlies the development concept of uranium production in the Navoi Mining and Metallurgy Combinat, Uzbekistan. Because this product has become a source of hard currency revenues for the Republic, there will be a significant increase in the processed ore and output of uranium oxide within the next few years. Uranium production in the Navoi Mining and Metallurgy Combinat represents a full-cycle operations ranging from geological survey through hydrometallurgical processing resulting in the output of uranium concentrate in the form of uranium protoxide-oxide (U 3 O 8 ). The NMMC uranium operations include the Hydrometallurgical Plant and three facilities accomplishing ISL mining facilities. A successful start on the development of the Uchkuduk deposit by ISL method in the 1960s gave rise to scientific and production approach for development of other uranium deposits of the infiltration bedded (sandstone) type. Uranium recovery by ISL has become a separate mining branch within the 30-year period of its history and the contribution of this branch in uranium production has steadily grown. Since 1995 all uranium produced by Navoi Mining and Metallurgy Combinat is attributed to ISL. During this evolution period of the ISL method, a whole range of systematic scientific research and practical works were carried out covering improvement of process flowsheets, equipment, operational methods and techniques for particular mining conditions at those specific sites. In co-operation with design and scientific research institutions, a significant number of scientific researches, test works, design and engineering projects were achieved in order to create optimal conditions for ISL mining and further processing of pregnant solutions by sorption as well as to appropriately equip

  15. Method of activating an article of passive ferrous or non-ferrous metal prior to carburising, nitriding and /or nitrocarburising

    DEFF Research Database (Denmark)

    2011-01-01

    Source: US2012111456A A method of activating an article of passive ferrous or non-ferrous metal by heating at least one compound containing nitrogen and carbon, wherein the article is treated with gaseous species derived from the compound. The activated article can be subsequently carburised......, nitrided or nitrocarburised in shorter time at lower temperature and resulting superior mechanical properties compared with non-activated articles and even articles of stainless steel, nickel alloy, cobalt alloy or titanium based material can be carburised, nitrided or nitrocarburised....

  16. Biennial activity report of Metallurgy Division for 1989 and 1990

    International Nuclear Information System (INIS)

    Kamachi Mudali, U.; Muraleedharan, P.; Parameswaran, P.; Swaminathan, K.; Sreedharan, O.M.

    1993-01-01

    This is the first divisional biennial report of the Metallurgy Division of Indira Gandhi Centre for Atomic Research, for the year 1989-1990, after formation of the Metallurgy Division in September 1988. Major areas of work in the Division relate to aqueous corrosion and localised corrosion, stress corrosion cracking and liquid metal corrosion, high temperature oxidation, thermodynamic studies, physical metallurgy studies for structure-property correlations and failure analyses. The principal materials of studies have been the austenitic stainless steels, the current materials of construction in the Fast Breeder Test Reactor and the candidate materials for the Prototype Fast Breeder Reactor

  17. Permanent magnets and its production by powder metallurgy

    Directory of Open Access Journals (Sweden)

    Enrique Herraiz Lalana

    2018-06-01

    Full Text Available In this work, the historical relationship between permanent magnets and powder metallurgy is reviewed. Powder metallurgy is a manufacturing technique based on the compaction of powders that are sintered to create a solid product. This technique was used in the production of permanent magnets for the first time in the 18th century and, nowadays, most permanent magnetic materials are manufacturing by this mean. Magnetic properties are highly dependent on the microstructure of the final product, the magnetic alignment of domains and presence of porosity, to mention a few, and powder metallurgy enables fine control of these factors.

  18. Biennial activity report of Metallurgy Division for 1989 and 1990

    Energy Technology Data Exchange (ETDEWEB)

    Kamachi Mudali, U; Muraleedharan, P; Parameswaran, P; Swaminathan, K; Sreedharan, O M [eds.; Indira Gandhi Centre for Atomic Research, Kalpakkam (India)

    1994-12-31

    This is the first divisional biennial report of the Metallurgy Division of Indira Gandhi Centre for Atomic Research, for the year 1989-1990, after formation of the Metallurgy Division in September 1988. Major areas of work in the Division relate to aqueous corrosion and localised corrosion, stress corrosion cracking and liquid metal corrosion, high temperature oxidation, thermodynamic studies, physical metallurgy studies for structure-property correlations and failure analyses. The principal materials of studies have been the austenitic stainless steels, the current materials of construction in the Fast Breeder Test Reactor and the candidate materials for the Prototype Fast Breeder Reactor 7 figs., 6 tabs., 2 ills.

  19. Were mercury emission factors for Chinese non-ferrous metal smelters overestimated? Evidence from onsite measurements in six smelters

    International Nuclear Information System (INIS)

    Zhang Lei; Wang Shuxiao; Wu Qingru; Meng Yang; Yang Hai; Wang Fengyang; Hao Jiming

    2012-01-01

    Non-ferrous metal smelting takes up a large proportion of the anthropogenic mercury emission inventory in China. Zinc, lead and copper smelting are three leading sources. Onsite measurements of mercury emissions were conducted for six smelters. The mercury emission factors were 0.09–2.98 g Hg/t metal produced. Acid plants with the double-conversion double-absorption process had mercury removal efficiency of over 99%. In the flue gas after acid plants, 45–88% was oxidized mercury which can be easily scavenged in the flue gas scrubber. 70–97% of the mercury was removed from the flue gas to the waste water and 1–17% to the sulfuric acid product. Totally 0.3–13.5% of the mercury in the metal concentrate was emitted to the atmosphere. Therefore, acid plants in non-ferrous metal smelters have significant co-benefit on mercury removal, and the mercury emission factors from Chinese non-ferrous metal smelters were probably overestimated in previous studies. - Highlights: ► Acid plants in smelters provide significant co-benefits for mercury removal (over 99%). ► Most of the mercury in metal concentrates for smelting ended up in waste water. ► Previously published emission factors for Chinese metal smelters were probably overestimated. - Acid plants in smelters have high mercury removal efficiency, and thus mercury emission factors for Chinese non-ferrous metal smelters were probably overestimated.

  20. Evaluation of iron transport from ferrous glycinate liposomes using ...

    African Journals Online (AJOL)

    Background: Iron fortification of foods is currently a strategy employed to fight iron deficiency in countries. Liposomes were assumed to be a potential carrier of iron supplements. Objective: The objective of this study was to investigate the iron transport from ferrous glycinate liposomes, and to estimate the effects of liposomal ...

  1. Metallurgy of steels for PWR pressure vessels

    International Nuclear Information System (INIS)

    Kepka, M.; Mocek, J.; Barackova, L.

    1980-01-01

    A survey and the chemical compositions are presented of reactor pressure vessel steels. The metallurgy is described of steel making for pressure vessels in Japan and the USSR. Both acidic and alkaline open-hearth steel is used for the manufacture of ingots. The leading world manufacturers of forging ingots for pressure vessels, however, exclusively use electric steel. Vacuum casting techniques are exclusively used. Experience is shown gained with the introduction of the manufacture of forging ingots for pressure vessels at SKODA, Plzen. The metallurgical procedure was tested utilizing alkaline open hearths, electric arc furnaces and facilities for vacuum casting of steel. Pure charge raw materials should be used for securing high steel purity. Prior to forging pressure vessel rings, not only should sufficiently big bottoms and heads be removed but also the ingot middle part should be scrapped showing higher contents of impurities and nonhomogeneous structure. (B.S.)

  2. Metallurgy of steels for PWR pressure vessels

    Energy Technology Data Exchange (ETDEWEB)

    Kepka, M; Mocek, J; Barackova, L [Skoda, Plzen (Czechoslovakia)

    1980-09-01

    A survey and the chemical compositions are presented of reactor pressure vessel steels. The metallurgy is described of steel making for pressure vessels in Japan and the USSR. Both acidic and alkaline open-hearth steel is used for the manufacture of ingots. The leading world manufacturers of forging ingots for pressure vessels, however, exclusively use electric steel. Vacuum casting techniques are exclusively used. Experience is shown gained with the introduction of the manufacture of forging ingots for pressure vessels at SKODA, Plzen. The metallurgical procedure was tested utilizing alkaline open hearths, electric arc furnaces and facilities for vacuum casting of steel. Pure charge raw materials should be used for securing high steel purity. Prior to forging pressure vessel rings, not only should sufficiently big bottoms and heads be removed but also the ingot middle part should be scrapped showing higher contents of impurities and nonhomogeneous structure.

  3. Chemistry and metallurgy in the Portuguese Empire

    Energy Technology Data Exchange (ETDEWEB)

    Habashi, F. [Laval Univ., Sainte-Foy, Quebec City, PQ (Canada)

    2000-10-01

    The foundation and expansion of the Portuguese Empire is sketched, with emphasis on the development of a new type of ship by Prince Henrique the Navigator (AD 1385-1460), known as the caravel. By virtue of its advanced design, it was capable of sailing the stormy seas at high speeds, and thereby was instrumental in extending Portuguese influence over vast territories in South America, Asia and Africa, extending Portuguese know-how in mining, metallurgy, chemistry and trade along with Christianity. The role played by the University of Coimbra, founded in 1306, and the contribution of the Brazilian Geological Survey, established in 1875, and of the School of Mines in Ouro Preto in Brazil in 1876, in the exploitation of the mineral wealth of the Portuguese colonies is chronicled.

  4. DETERMINATION OF THE RATES AND PRODUCTS OF FERROUS IRON OXIDATION IN ARSENIC-CONTAMINATED POND WATER.

    Science.gov (United States)

    Dissolved ferrous iron and arsenic in the presence of insufficient oxygenated ground water is released into a pond. When the mixing of ferrous iron and oxygenated water within the pond occurs, the ferrous iron is oxidized and precipitated as an iron oxide. Groups of experiments...

  5. 40 CFR 464.30 - Applicability; description of the ferrous casting subcategory.

    Science.gov (United States)

    2010-07-01

    ... ferrous casting subcategory. 464.30 Section 464.30 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) EFFLUENT GUIDELINES AND STANDARDS METAL MOLDING AND CASTING POINT SOURCE CATEGORY Ferrous Casting Subcategory § 464.30 Applicability; description of the ferrous casting subcategory. The...

  6. Structural and electrical properties of copper-nickel-aluminum alloys obtained by conventional powder metallurgy method

    International Nuclear Information System (INIS)

    Monteiro, Waldemar A.; Carrio, Juan A.G.; Silveira, C.R. da; Pertile, H.K.S.

    2009-01-01

    This work looked for to search out systematically, in scale of laboratory, copper-nickel-aluminum alloys (Cu-Ni-Al) with conventional powder metallurgy processing, in view of the maintenance of the electric and mechanical properties with the intention of getting electric connectors of high performance or high mechanical damping. After cold uniaxial pressing (1000 kPa), sintering (780 deg C) and convenient homogenization treatments (500 deg C for different times) under vacuum (powder metallurgy), the obtained Cu-Ni-Al alloys were characterized by optical microscopy, electrical conductivity, Vickers hardness. X rays powder diffraction data were collected for the sintered samples in order to a structural and microstructural analysis. The comparative analysis is based on the sintered density, hardness, macrostructures and microstructures of the samples. (author)

  7. Application of powder metallurgy in production of nuclear fuels for research and power reactors

    International Nuclear Information System (INIS)

    Fukuda, Kosaku

    2000-01-01

    Powder metallurgy has been applied in many of the processes of nuclear fuel fabrication, which has contributed, to a great progress of the nuclear technology to date. Evolution of nuclear fuels still continues to meet various emerging demands in terms of enhanced safety, economical effectiveness, non-proliferation and environmental mitigation. This paper reviews recent progress of nuclear fuels of research and power reactors, in particular, focusing on the powder metallurgy application. First, the review is made on plate type fuels for research reactors, inter alia, silicide fuel which is prevailing worldwide from the viewpoint of non-proliferation. The relation between fabrication and irradiation behavior is also discussed. Next, oxide fuels including MOX are reviewed. Recent interests of UO 2 are directed toward large grain pellets and burnable absorber pellets, both of which arise from requirement of extended burnup. Finally, the MOX fuel for thermal reactors is reviewed. (author)

  8. Proceedings of the International Symposium on quantitative description of metal extraction processes

    International Nuclear Information System (INIS)

    Themelis, N.J.

    1991-01-01

    This book contains the proceedings of the H.H. Kellogg International Symposium. Topics include: Extractive metallurgy; Thermochemical phenomena in metallurgy; Thermodynamic modeling of metallurgical processes; and Transport and rate phenomena in metallurgical extraction

  9. Scandium: its occurrence, chemistry, physics, metallurgy, biology, and technology

    International Nuclear Information System (INIS)

    Horovitz, C.T.

    1975-01-01

    This book describes the following aspects of scandium: discovery and history, occurrence in nature, geochemistry and mineralogy, chemical, physical and technological properties, fabrication and metallurgy, its biological significance and toxicology, and its uses. (Extensive references for each chapter)

  10. Weldability of powder-metallurgy molybdenum with low oxygen content

    International Nuclear Information System (INIS)

    Hiraoka, Yutaka; Okada, Masatoshi

    1987-01-01

    Relationships between the formation of weld pores and the chemical compositions in powder-metallurgy molybdenum were investigated. It is suggested that almost 100% of Ca and Mg form oxides. In contrast, Fe, Ni, Cr and Al, Si only partly form oxides. A powder-metallurgy molybdenum containing less than 84 at.ppm oxygen did not show any large weld pores. The reduction of the oxygen content was achieved by purifying the molybdenum powder. (orig.) [de

  11. Niobium-base superalloys via powder metallurgy technology

    International Nuclear Information System (INIS)

    Loria, E.A.

    1987-01-01

    This paper provides some insight into an area that has been neglected, namely the possibility of developing high-strength, niobium-base alloys by improved oxidation resistance via the consolidation of rapidly solidified powders. Powder metallurgy (P/M) is an attractive processing technique because of its flexibility and versatility, and it may provide the alloys with properties and workability not obtainable via metal casting. A critical review of both U.S. and Russian literature is presented along with suggestions on the most promising compositions and processing techniques available to meet these competing goals. Previous work on many niobium alloys reveals that long term properties are retained well above those obtained on nickel-base superalloys. Cast and wrought alloys extend specific strength beyond 1200 0 C (2200 0 F), but lack oxidation resistance. Remarkable oxidation resistance is obtained, however, on miniature castings of certain ternary alloys which are too brittle for any processing. A better understanding of the oxidation mechanism is necessary before the proper P/M (RST) approach is taken on compositions which could provide compatibility between the two competing goals through grain refinement and a homogeneous distribution of the contributory phases. Finally, ways to up-scale production of Nb powder are discussed, including thermodynamic feasibility for the direct reduction of NbCl/sub 5/ in a 1.5 MW plasma reactor

  12. Design of powder metallurgy titanium alloys and composites

    International Nuclear Information System (INIS)

    Liu, Y.; Chen, L.F.; Tang, H.P.; Liu, C.T.; Liu, B.; Huang, B.Y.

    2006-01-01

    Low cost and good performance are two major factors virtually important for Ti alloy development. In this paper, we have studied the effects of alloying elements, thermo-mechanical treatment and particle reinforcement on microstructures and mechanical properties of powder metallurgy (PM) Ti alloys and their composites. Our results indicate that low cost PM Ti alloys and their composites with attractive properties can be fabricated through a single compaction-sintering process, although secondary treatments are required for high performance applications. Three new PM Ti alloys and one TiC/Ti composite of high performance are developed, and new design principles are also proposed. For design of PM Ti alloys, addition of alloying elements has the beneficial effect of enhanced sintering and/or improved mechanical properties. For example, Fe element accelerates the sintering process, Mo and Al are good candidates for solution strengthening, and rare earth elements effectively increase the material ductility by scavenging oxygen from the Ti matrix. For the design of Ti-based composites, in situ formation of strengthening particles and solid solution hardening of the matrix both should be considered simultaneously for alloy development. Cr 3 C 2 is found to be a very suitable additive for processing particle reinforced Ti composites

  13. Manufacture of good-weldable low oxygen molybdenum by powder metallurgy

    International Nuclear Information System (INIS)

    Hiraoka, Yutaka; Okada, Masatoshi; Akiyama, Takashi; Yamafuchi, Yasuo.

    1984-01-01

    In general most of commercial molybdenum is produced by the powder metallurgy method and is utilized as a superior heat-resisting material in many fields. Moreover, molybdenum is expected to be used as the first-wall components of JT-60 (JAERI Tokamak-60). However, one of major problems on molybdenum, particularly on powder metallurgy molybdenum, is that any sound welded joint is hard to be obtainable. In many cases weld pores are formed on welding and, therefore, ductility of the welded joint is severely degraded. The object of the present work is to get a sound welded joint without any weld pores by reducing impurity levels in the material. The materials were produced by modifying one or several parts in the ordinary manufacturing process of powder metallurgy molybdenum. Oxygen, nitrogen, carbon and other principal metallic impurities were chemically analysed. The above materials were then subjected to electron-beam-welding by using a melt-run technique, and the soundness of the welded joints was examined by optical microscopy. (author)

  14. Parent-martensite interface structure in ferrous systems

    International Nuclear Information System (INIS)

    Ma, X.; Pond, R.C.

    2007-01-01

    Recently, a Topological Model of martensitic transformations has been presented wherein the habit plane is a semi-coherent structure, and the transformation mechanism is shown explicitly to be diffusionless. This approach is used here to model martensitic transformations in ferrous alloys. The habit plane comprises coherent (1 1 1) γ parallel (0 1 1) α terraces where the coherency strains are accommodated by a network of dislocations, originating in the martensite phase, and disconnections (transformation dislocations). The disconnections can move conservatively across the interface, thereby effecting the transformation. Since the disconnections exhibit step character, the overall habit plane deviates from the terrace plane. A range of network geometries is predicted corresponding to orientation relationships varying from Nishiyama-Wasserman to Kurdjumov-Sachs. This range of solutions includes habit planes close to {2 9 5}, {5 7 5} and {1 2 1}, in good agreement with experimental observations in various ferrous alloys

  15. Wear mechanisms in powder metallurgy high speed steels matrix composites

    International Nuclear Information System (INIS)

    Gordo, E.; Martinez, M. A.; Torralba, J. M.; Jimenez, J. A.

    2001-01-01

    The development of metal matrix composites has a major interest for automotive and cutting tools industries since they possess better mechanical properties and wear resistance than corresponding base materials. One of the manufacturing methods for these materials includes processing by powder metallurgy techniques. in this case, blending of both, base material and reinforcement powders constitute the most important process in order to achieve a homogeneous distribution of second phase particles. in the present work, composite materials of M3/2 tool steel reinforced with 2.5,5 and 8 vol% of niobium carbide have been prepared. In order to ensure a homogeneous mix, powders of both materials were mixed by dry high-energy mechanical milling at 200 r.p.m. for 40 h. After a recovering annealing, two routes for consolidate were followed die pressing and vacuum sintering, and hot isostatic pressing (HIP). Pin-on-disc tests were carried out to evaluate wear behaviour in all the materials. Results show that ceramic particles additions improve wear resistance of base material. (Author) 9 refs

  16. Removal of chlorite by reaction with ferrous iron

    OpenAIRE

    Iatrou, Angela

    1991-01-01

    The use of chlorine dioxide as an oxidant and/or disinfectant for drinking water treatment has been an alternative considered when utilities seek to control trihalomethane concentrations. However, concern regarding residual concentrations of chlorite and chlorate have resulted in limitations on applied chlorine dioxide dosages. This study describes the use of ferrous iron as a possible reducing agent for the elimination of residual chlorite from drinking water.

  17. Adsorption of ferrous ions onto montmorillonites

    Science.gov (United States)

    Qin, Dawei; Niu, Xia; Qiao, Min; Liu, Gang; Li, Hongxin; Meng, Zhenxiao

    2015-04-01

    The adsorption of Fe (II) onto montmorillonites was investigated through initial concentration, contact time, pH and temperature. During the whole adsorption process, the ascorbic acid (Vitamin C) was added as a kind of antioxidant, at the same time, deionized water (after boiling) and nitrogen protection were also used to avoid oxidation. The Fe2+/Fetotal ratio of the iron exists in the Fe-montmorillonites was found more than 95%. Two kinetic models, including pseudo-first-order and pseudo-second-order model, were used to analyze the adsorption process of Fe (II) on montmorillonites. The results of our study showed that adsorption process fitted with pseudo-second-order well. Adsorption isotherms showed that Langmuir model was better than Freundlich model. The thermodynamic parameters ΔG0 and ΔH0 were 3.696 kJ/mol and 6.689 kJ/mol (we just gave the values at 298 K), respectively. The positive values at different temperatures showed that the adsorption process was non-spontaneous and endothermic. The characteristics of materials were determined by X-ray diffraction (XRD), Fourier transform infrared (FT-IR), Surface area and porosity analyzer, Thermogravimetric analysis (TGA), Differential scanning calorimeter (DSC) and Zeta potential distribution.

  18. Surface metallurgy of cemented carbide tools

    International Nuclear Information System (INIS)

    Chopra, K.L.; Kashyap, S.C.; Rao, T.V.; Rajagopalan, S.; Srivastava, P.K.

    1983-01-01

    Transition metal carbides, owing to their high melting point, hardness and wear resistance, are potential candidates for specific application in rockets, nuclear engineering equipment and cutting tools. Tungsten carbide sintered with a binder (either cobalt metal or a mixture of Co + TiC and/or TaC(NbC)) is used for cutting tools. The surface metallurgy of several commercially available cemented carbide tools was studied by Auger electron spectroscopy and X-ray photoelectron spectroscopy techniques. The tool surfaces were contaminated by adsorbed oxygen up to a depth of nearly 0.3 μm causing deterioration of the mechanical properties of the tools. Studies of fractured samples indicated that the tool surfaces were prone to oxygen adsorption. The fracture path passes through the cobalt-rich regions. The ineffectiveness of a worn cutting tool is attributed to the presence of excessive iron from the steel workpiece and carbon and oxygen in the surface layers of the tool. The use of appropriate hard coatings on cemented carbide tools is suggested. (Auth.)

  19. The metallurgy of superalloys part 2

    International Nuclear Information System (INIS)

    Abdelazim, M.E.; Hammad, F.H.

    1990-01-01

    This is part II of the report titled 'the metallurgy of superalloys'. It deals with the effect of heat treatment and operating conditions (thermal exposure and environment) on the mechanical properties of superalloys. The heat treatment is important in the development of superalloys through that it controls type, amount, size shape and distribution of the precipitate and the grain size of the matrix. The thermal exposure leads to reduction in the amount of the primary carbides and to precipitation of secondary carbides. Also it leads to the agglomeration and coarsening of gamma or the transformation of gamma phase to phase. The environment may lead to the internal oxidation, carburization, decarburization or sulphidization of the superalloys which may result in the degradation of their mechanical properties. This part gives also an example of applications of superalloys in the field of nuclear reactors especially high temperature-gas cooled reactors. Joined with this part a table which contains the major superalloys including its chemical analysis, creep rupture strength and some of its applications. 1 tab

  20. The metallurgy of superalloys part 1

    International Nuclear Information System (INIS)

    Abdelazim, M.E.; Hammad, F.H.

    1990-01-01

    This is part I of the report titled 'the metallurgy of superalloys'. In this part the structure, phases and systems of superalloys are reviewed. The role of alloying elements in the design of superalloys and the mechanical properties of superalloys are also reviewed. Superalloys are important in high temperature technology, especially above 700 degree c. They are 'super' mainly because their creep and stress rupture resistances are very high. Superalloys are based on an austenitic matrix including secondary phases, mainly gamma precipitates, inter and intragranular carbides mainly M 23 C 6 and M 6 C. They are classified into three systems, Ni-base, Fe-Ni base and Ce-base alloys. Different alloying elements mainly Cr, Mo, Al, Ti are added to increase the strength either by solid solution hardening (Cr, Mo, Al), precipitation hardening (A 1, Ti to produce gamma) or by dispersion hardening (Cr, Mo to form M 23 C 6 and M 6 C carbides) and to increase the oxidation resistance (Cr, Al). 3 tab., 2 fig

  1. Boride particles in a powder metallurgy superalloy

    Energy Technology Data Exchange (ETDEWEB)

    Witt, M C; Charles, J A

    1985-12-01

    Using optical and electron metallography, the composition, morphology, and distribution of M/sub 3/B/sub 2/ borides in as-hipped (hot isostatically pressed) samples of the powder metallurgy superalloy Nimonic AP1 have been determined. Two types of boride are present depending on the HIP temperature. Hipping below the boride solvus results in low-aspect ratio particles, distributed both inter- and intragranularly. Hipping above the boride solvus produces high-aspect ratio particles which are exclusively intergranular. A small difference in both lattice parameter and composition has been measured. Electron energy loss spectroscopy of the particles has confirmed the presence of boron, and laser ion-induced mass analysis has indicated a low carbon level. The higher susceptibility to edge cracking during forging of material hipped above the boride solvus is related to the boride morphology. Studies of the subsequent recrystallization of the forged samples have indicated that necklace formation is neither inhibited nor accelerated by the presence of grain boundary borides. 18 references.

  2. Ferrous bisglycinate 25 mg iron is as effective as ferrous sulfate 50 mg iron in the prophylaxis of iron deficiency and anemia during pregnancy in a randomized trial

    DEFF Research Database (Denmark)

    Milman, Nils; Jønsson, Lisbeth; Dyre, Pernille

    2014-01-01

    OBJECTIVE: To compare the effects of oral ferrous bisglycinate 25 mg iron/day vs. ferrous sulfate 50 mg iron/day in the prevention of iron deficiency (ID) and iron deficiency anemia (IDA) in pregnant women. Design: Randomized, double-blind, intention-to-treat study. Setting: Antenatal care clinic...

  3. Ferrous Ion and Medium Composition Effects on Acidogenic Phase in Biobutanol Production from Molasses

    Science.gov (United States)

    Restiawaty, E.; Grinanda, D.

    2017-07-01

    Clostridium acetobutylicum B530 has ability to convert sugar into biobutanol through two phases, i.e. acidogenic and solventogenic. This fermentation process is often hampered by high raw material cost and low product yield. In order to suppress the production cost, the molasses, a byproduct of sugar cane process production, was used as carbon source in this research. Molasses has nitrogen content in a small amount, thus could be negating the beef extract component, which is expected not to affect the growth of C. acetobutylicum B530 and also can reduce the production cost. In addition, a certain amount of Fe2+ (ferrous ion), a precursor in the formation of the enzyme ferredoxin, was added to the fermentation medium to contribute in the synthesis of acetyl-CoA, so that the formation of acidogenic products such as butyric acid and acetic acid is affected. This study aimed to investigate the effect of ferrous ion and the medium composition in acidogenic phase. The addition of 20 ppm FeSO4.7H2O in the fermentation medium without beef extract can increase the concentration of butyric acid by 20% at a temperature of 35°C, while acetic acid concentration decreased by 6%. According to those results, it is expected that the product selectivity of butanol will increase in solventogenic phase. In addition, the removal of beef extract in the fermentation medium does not affect the kinetics of growth of C. acetobutylicum B530.

  4. Cyanide binding to ferrous and ferric microperoxidase-11.

    Science.gov (United States)

    Ascenzi, Paolo; Sbardella, Diego; Santucci, Roberto; Coletta, Massimo

    2016-07-01

    Microperoxidase-11 (MP11) is an undecapeptide derived from horse heart cytochrome c (cytc). MP11 is characterized by a covalently linked solvent-exposed heme group, the heme-Fe atom being axially coordinated by a histidyl residue. Here, the reactions of ferrous and ferric MP11 (MP11-Fe(II) and MP11-Fe(III), respectively) with cyanide have been investigated from the kinetic and thermodynamic viewpoints, at pH 7.0 and 20.0 °C. Values of the second-order rate constant for cyanide binding to MP11-Fe(II) and MP11-Fe(III) are 4.5 M(-1) s(-1) and 8.9 × 10(3) M(-1) s(-1), respectively. Values of the first-order rate constant for cyanide dissociation from ligated MP11-Fe(II) and MP11-Fe(III) are 1.8 × 10(-1) s(-1) and 1.5 × 10(-3) s(-1), respectively. Values of the dissociation equilibrium constant for cyanide binding to MP11-Fe(II) and MP11-Fe(III) are 3.7 × 10(-2) and 1.7 × 10(-7) M, respectively, matching very well with those calculated from kinetic parameters so that no intermediate species seem to be involved in the ligand-binding process. The pH-dependence of cyanide binding to MP11-Fe(III) indicates that CN(-) is the only binding species. Present results have been analyzed in parallel with those of several heme-proteins, suggesting that (1) the ligand accessibility to the metal center and cyanide ionization may modulate the formation of heme-Fe-cyanide complexes, and (2) the general polarity of the heme pocket and/or hydrogen bonding of the heme-bound ligand may affect cyanide exit from the protein matrix. Microperoxidase-11 (MP11) is an undecapeptide derived from horse heart cytochrome c. Penta-coordinated MP11 displays a very high reactivity towards cyanide, whereas the reactivity of hexa-coordinated horse heart cytochrome c is very low.

  5. Emission profiles of polychlorinated dibenzodioxins, polychlorinated dibenzofurans (PCDD/Fs), dioxin-like PCBs and hexachlorobenzene (HCB) from secondary metallurgy industries in Portugal.

    Science.gov (United States)

    Antunes, Pedro; Viana, Paula; Vinhas, Tereza; Rivera, J; Gaspar, Elvira M S M

    2012-09-01

    This paper reports, for the first time, a study of dioxin emissions from 10 siderurgies and metallurgies, secondary copper, aluminum and lead metallurgies, in Portugal. The study reports the emission factors and total emission amounts of PCDD/Fs, dioxin-like PCBs and hexachlorobenzene (HCB). The congener patterns were characterized and are discussed. The results showed that the total amount of PCDFs is higher than PCDDs in flue gas of each industrial unit. The toxic equivalent emission factors of pollutants emitted are 3098-3338 ngI-TEQt(-1) for PCDD/Fs and 597-659 ng I-TEQt(-1) for dioxin-like PCBs in siderurgies production (total estimated emission amounts released to atmosphere of 3.9-4.5 g I-TEQyr(-1)), 50-152 ng I-TEQt(-1) for PCDD/Fs and 24-121 ng I-TEQt(-1) for dioxin-like PCBs in ferrous foundries production (total estimated emission amounts released to atmosphere of 0.0010-0.0016 g I-TEQyr(-1)) and 5.8-5715 ng I-TEQt(-1) for PCDD/Fs and 0.49-259 ng I-TEQt(-1) for dioxin-like PCBs in non-ferrous foundries production (total estimated emission amounts released to atmosphere of 0.00014-0.12 g I-TEQyr(-1)). The HCB emission from siderurgies production is 0.94-3.2 mg t(-1) (total estimated emission amounts released 0.94-3.8 g yr(-1)), being much smaller, residual, in the emissions of the other types of plants (0.0012-0.026 mg t(-1) production and total estimated emission amounts released to atmosphere of 0.013-1.7 mg yr(-1)). Copyright © 2012 Elsevier Ltd. All rights reserved.

  6. Corrosion resistant zirconium alloys prepared by powder metallurgy

    International Nuclear Information System (INIS)

    Wojeik, C.C.

    1984-01-01

    Pure zirconium and zirconium 2.5% niobium were prepared by powder metallurgy. The powders were prepared directly from sponge and consolidated by cold isostatic pressing and sintering. Hot isostatic pressing was also used to obtain full density after sintering. For pure zirconium the effects of particle size, compaction pressure, sintering temperature and purity were investigated. Fully densified zirconium and Zr-2.5%Nb exhibited tensile properties comparable to cast material at room temperature and 300 0 F (149 0 C). Pressed and sintered material having density of 94-99% had slightly lower tensile properties. Corrosion tests were performed in boiling 65% H/sub 2/SO/sub 4/, 70% HNO/sub 3/, 20% HCl and 20% HCl + 500 ppm FeCl/sub 3/ (a known pitting solution). For fully dense material the observed corrosion behavior was nearly equivalent to cast material. A slightly higher rate of attack was observed for samples which were only 94-99% dense. Welding tests were also performed on zirconium and Zr-2.5%Nb alloy. Unlike P/M titanium alloys, these materials had good weldability due to the lower content of volatile impurities in the powder. A slight amount of weld porosity was observed but joint efficiencies were always not 100%, even for 94-99% density samples. Several practical applications of the P/M processed material will be briefly described

  7. 78 FR 8202 - Meeting of the Joint ACRS Subcommittees on Thermal Hydraulic Phenomena and Materials, Metallurgy...

    Science.gov (United States)

    2013-02-05

    ... NUCLEAR REGULATORY COMMISSION Advisory Committee on Reactor Safeguards (ACRS) Meeting of the Joint ACRS Subcommittees on Thermal Hydraulic Phenomena and Materials, Metallurgy and Reactor Fuels; Notice of Meeting The Joint ACRS Subcommittees on Thermal Hydraulic Phenomena and Materials, Metallurgy and...

  8. Experimental Characterization of Aluminum-Based Hybrid Composites Obtained Through Powder Metallurgy

    Science.gov (United States)

    Marcu, D. F.; Buzatu, M.; Ghica, V. G.; Petrescu, M. I.; Popescu, G.; Niculescu, F.; Iacob, G.

    2018-06-01

    The paper presents some experimental results concerning fabrication through powder metallurgy (P/M) of aluminum-based hybrid composites - Al/Al2O3/Gr. In order to understand the mechanisms that occur during the P/M processes of obtaining Al/Al2O3/Gr composite, we correlated the physical characteristics with their micro-structural characteristics. The characterization was performed using analysis techniques specific for P/M process, SEM-EDS and XRD analyses. Micro-structural characterization of the composites has revealed fairly uniform distribution this resulting in good properties of the final composite material.

  9. The Metallurgy of some indian swords

    Directory of Open Access Journals (Sweden)

    Williams, Alan

    2007-12-01

    Full Text Available The metallurgy of Indian swords shows many differences from that of European swords. The distinction between "Damascus Steel" (or wootz and crucible steel is explained. Ten broken blades from the Armoury of the Nizams of Hyderabad were made available for microscopic examination. Six of these seem to been made from crucible steels, and are of notably high quality. By contrast, a group of six randomly collected from Private Collections in England were also examined. Only one of these was made of crucible steel, and three of the others were of very mediocre quality. This perhaps represents the quality of blades available to the average Indian soldier.

    La metalurgia de las espadas indias presenta notables diferencias en comparación con la de las europeas. Se explica la distinción entre el ‘acero de Damasco’ (o wootz y el acero de crisol. Se ha realizado un análisis microscópico de un conjunto de diez hojas rotas de espada depositadas en la Armería de los Nizams de Hyderabad. Seis de ellas parecen haber sido realizadas a partir de acero de crisol, y son de elevada calidad. En contraste, se examinó también un grupo de seis espadas de colecciones privadas en Inglaterra. Sólo una de ellas estaba fabricada con acero de crisol, y tres de las otras eran de calidad muy mediocre. Esto representa quizá la calidad de las hojas de espada al alcance del soldado medio indio.

  10. Chemical dosimetry of Gammacell with ferrous sulfate

    International Nuclear Information System (INIS)

    Austerlitz, Carlos; Campos, Diana; Ferreira, Maria Clara; Benhabib, Sidi; Panettieri, Vanesa; Lopes Filho, Alfredo

    2009-01-01

    The influence of Compton scatter radiation from a Gammacell-220 on the ferric-ion yield [G(Fe +3 )] was determined for the Fricke dosimetry. Monte Carlo simulations were performed using the PENELOPE code to obtain the photon spectrum of a 60 Co Nordion teletherapy unit at a depth of 2 cm in a 50x50x50 cm 3 cubic water tank. Published values of G(Fe +3 ) were fitted by a third order polynomial and the resulting equation was used to determine a mean chemical yield of such unit. The same procedure was performed over the spectrum of a Gammacell-220 published by the ASTM. The mass-energy absorption coefficient for the Fricke solution was weighted over the Gammacell-220 spectrum and compared against the Nordion spectrum. The ratio between the mean chemical yields was used to determine the influence of the Compton scatter radiation on the value of G(Fe +3 ). The ratio of the mass-energy absorption coefficient of water to Fricke solution was used to convert the absorbed dose in the Fricke solution to absorbed dose to water. From the results obtained it was concluded that the dosimetry of a Gammacell-220 with the Fricke dosimeter may overestimate the measured absorbed dose to water by a factor of 1.01 due to changes in the G(Fe +3 ) value. Differences in the mean energy of the spectra can lead to large errors in the isodoses curves of samples irradiated with both equipment. To establish evidence that the radiation process will provide the desired results, the knowledge of the radiation spectrum is needed. Alternatively, whenever it is possible, the dosimetry should be performed by positioning the capsule with the Fricke solution inside of dummy samples (author)

  11. Biennial activity report of Metallurgy Programme - 1985 and 1986

    International Nuclear Information System (INIS)

    Mallika, C.; Sreenivasan, P.R.; Muraleedharan, P.; Shyamsunder, M.T.; Kuppuswami, P.; Sampath, N.; Bhaduri, A.K.; Sreedharan, O.M.

    1988-01-01

    The biennial activity report of the Metallurgy Programme of the Indira Gandhi Centre for Atomic Research covers the period of the years 1985 and 1986. Along with NDT, welding metallurgy, low cycle fatigue, creep and creep fatigue interactions, structure-property correlations, thermodynamics and corrosion metallurgy of alloy steels with respect to their compatibility with aqueous and liquid sodium environments continue to be the major thrust areas of the Programme. Some of the basic research contributions of the Programme are: the observation of uniform and homogeneous distribution of voids in cyclically deformed 304 SS, the role of grain boundaries and precipitation in dynamic strain ageing of 316 SS and the determination of the activities of component metals in 316 and 304 SS by metastable EMF method. (author)

  12. Preparation, physical characterization, and stability of Ferrous-Chitosan microcapsules using different iron sources

    Science.gov (United States)

    Handayani, Noer Abyor; Luthfansyah, M.; Krisanti, Elsa; Kartohardjono, Sutrasno; Mulia, Kamarza

    2017-11-01

    Dietary modification, supplementation and food fortification are common strategies to alleviate iron deficiencies. Fortification of food is an effective long-term approach to improve iron status of populations. Fortification by adding iron directly to food will cause sensory problems and decrease its bioavailability. The purpose of iron encapsulation is: (1) to improve iron bioavailability, by preventing oxidation and contact with inhibitors and competitors; and (2) to disguise the rancid aroma and flavor of iron. A microcapsule formulation of two suitable iron compounds (iron II fumarate and iron II gluconate) using chitosan as a biodegradable polymer will be very important. Freeze dryer was also used for completing the iron microencapsulation process. The main objective of the present study was to prepare and characterize the iron-chitosan microcapsules. Physical characterization, i.e. encapsulation efficiency, iron loading capacity, and SEM, were also discussed in this paper. The stability of microencapsulated iron under simulated gastrointestinal conditions was also investigated, as well. Both iron sources were highly encapsulated, ranging from 71.5% to 98.5%. Furthermore, the highest ferrous fumarate and ferrous gluconate loaded were 1.9% and 4.8%, respectively. About 1.04% to 9.17% and 45.17% to 75.19% of Fe II and total Fe, were released in simulated gastric fluid for two hours and in simulated intestinal fluid for six hours, respectively.

  13. Ferrous and ferric ions-based high-throughput screening strategy for nitrile hydratase and amidase.

    Science.gov (United States)

    Lin, Zhi-Jian; Zheng, Ren-Chao; Lei, Li-Hua; Zheng, Yu-Guo; Shen, Yin-Chu

    2011-06-01

    Rapid and direct screening of nitrile-converting enzymes is of great importance in the development of industrial biocatalytic process for pharmaceuticals and fine chemicals. In this paper, a combination of ferrous and ferric ions was used to establish a novel colorimetric screening method for nitrile hydratase and amidase with α-amino nitriles and α-amino amides as substrates, respectively. Ferrous and ferric ions reacted sequentially with the cyanide dissociated spontaneously from α-amino nitrile solution, forming a characteristic deep blue precipitate. They were also sensitive to weak basicity due to the presence of amino amide, resulting in a yellow precipitate. When amino amide was further hydrolyzed to amino acid, it gave a light yellow solution. Mechanisms of color changes were further proposed. Using this method, two isolates with nitrile hydratase activity towards 2-amino-2,3-dimethyl butyronitrile, one strain capable of hydrating 2-amino-4-(hydroxymethyl phosphiny) butyronitrile and another microbe exhibiting amidase activity against 2-amino-4-methylsulfanyl butyrlamide were obtained from soil samples and culture collections of our laboratory. Versatility of this method enabled it the first direct and inexpensive high-throughput screening system for both nitrile hydratase and amidase. Copyright © 2011 Elsevier B.V. All rights reserved.

  14. Recycling of ferrous sulfate by the synthesis of a new super oxidant material 'Referox'

    Energy Technology Data Exchange (ETDEWEB)

    Evrard, O. [Universite Henri Poincare, Vandoeuvre (France); Dupre, B.; Jeannot, C.; Kanari, N.; Gaballah, I.; Ninane, L.; Verstraete, W.; Denomme, S.; Belsue, M.

    2001-07-01

    This European Union-sponsored project was initiated to develop a process to recycle industrial ferrous sulfate by the synthesis of a superoxidant containing hexavalent (FeVI) iron. Hexavalent iron, also called ferrates, can be used in decontamination of industrial effluents, decolorisation and purification of effluents from the textile and tanning industries, oxidation of cyanide to cyanates, soil remediation, water treatment and in a variety of other processes. Dry synthesis of potassium ferrate, using calcium hypochlorite as the oxidizing agent, was successful. By using chlorine instead of calcium hypochlorite and by partially substituting sodium hydroxide for potassium hydroxide the cost of the synthesis was significantly reduced. Recycling of ferrous sulfate at room temperature by the synthesis of potassium ferrate (FeVI) using gaseous chlorine instead of solid calcium hypochlorite was also successful. The yield of the synthesis was about 65 per cent for the used industrial ferrous sulfate samples. Large scale experimentation of the potassium ferrate synthesis was also carried out, obtaining potassium ferrate that remained stable for several months. The ferrates were used in the treatment of drinking water, wastewater, soil remediation, and effluent decontamination. Encouraging results were obtained. An additional benefit found was that use of the ferrates as bactericide for water treatment instead of chlorine gas eliminates the generation of halo-organic compounds which are suspected to be carcinogenic. 2 figs.

  15. Machinability of zinc-aluminum alloy5; zamzk5; alloy produced by powder metallurgy

    International Nuclear Information System (INIS)

    Adnan, I.O.; Momani, M.A.A.

    2007-01-01

    Powder metallurgy process (P/M) is repeatedly reported as a near-net or net-shape manufacturing process with the ability of producing parts of complicated or intricate shapes with high required dimensional accuracy and high surface quality. However, some finishing and machining operations are sometimes necessary and must be done to meet dimensional tolerances or accommodate design features that can be achieved during compaction such as transverse holes, undercuts and threads. Therefore, it is necessary to study the machinability of P/M products. ZAMAK5 alloy is widely used in engineering applications in the automobile industry, particularly in the manufacturing of bushes and recently self -lubricated bearings which are manufactured by the P/M process. Therefore it is anticipated that studying the machinability of this alloy as produced by the powder metallurgy process is worthwhile investigating. In this paper, the machinability of ZAMAK5, alloy produced by powder metallurgy, under different cutting conditions of speed, depth of cut and feed rate is carried out. Surface roughness was used as a criterion for assessing machinability at the different conditions. It was found that specimens compacted at 475 MPa and having 1% addition of zinc stearates as a binder and lubricant gave better surface quality than those produced at 550 MPa compacting pressure,whereas at 1.5% addition of zinc stearates produced worse surface quality (i.e. Higher surface roughness than in case of 475 MPa compacting pressure). On the whole, the results of the experimental work revealed that the surface roughness at the different cutting conditions remained within the accepted level in industry, less than 2 microns. (author)

  16. Metallurgical examination of powder metallurgy uranium alloy welds

    International Nuclear Information System (INIS)

    Morrison, A.G.M.; Dobbins, A.G.; Holbert, R.K.; Doughty, M.W.

    1986-01-01

    Inertia welding provided a successful technique for joining full density, powder metallurgy uranium-6 wt pct niobium alloy. Initial joining attempts concentrated on the electron beam method, but this method failed to produce a sound weld. The electron beam welds and the inertia welds were evaluated by radiography and metallography. Electron beam welds were attempted on powder metallurgy plates which contained various levels of oxygen and nitrogen. All welds were porous. Sixteen inertia welds were made and all welds were radiographically sound. The tensile properties of the joints were found to be equivalent to the p/m base metal properties

  17. Summarizing of new techniques in uranium mining and metallurgy

    International Nuclear Information System (INIS)

    Wang Delin; Zhang Fei; Su Yanru; Zeng Yijun; Meng Jin

    2010-01-01

    According to character of national resources and uranium mining and metallurgical science and technology members research achievements, new techniques in ten scientific research area of in-situ leaching, heap leaching, multi-metal comprehensive recovery, bio-metallurgy etc. for 10 years is introduced in this paper. The level of innovation ability is shown by technical index, resources recovery and reduction capital cost etc. datum. The application bound of natural uranium resource is enlarged and production ability of national uranium is increased. It is put forward renovation and development ideas for uranium mining and metallurgy. (authors)

  18. Metallurgy and properties of plasma spray formed materials

    Science.gov (United States)

    Mckechnie, T. N.; Liaw, Y. K.; Zimmerman, F. R.; Poorman, R. M.

    1992-01-01

    Understanding the fundamental metallurgy of vacuum plasma spray formed materials is the key to enhancing and developing full material properties. Investigations have shown that the microstructure of plasma sprayed materials must evolve from a powder splat morphology to a recrystallized grain structure to assure high strength and ductility. A fully, or near fully, dense material that exhibits a powder splat morphology will perform as a brittle material compared to a recrystallized grain structure for the same amount of porosity. Metallurgy and material properties of nickel, iron, and copper base alloys will be presented and correlated to microstructure.

  19. Fish Proteins as Targets of Ferrous-Catalyzed Oxidation: Identification of Protein Carbonyls by Fluorescent Labeling on Two-Dimensional Gels and MALDI-TOF/TOF Mass Spectrometry

    DEFF Research Database (Denmark)

    Pazos, Manuel; da Rocha, Angela Pereira; Roepstorff, Peter

    2011-01-01

    Protein oxidation in fish meat is considered to affect negatively the muscle texture. An important source of free radicals taking part in this process is Fenton's reaction dependent on ferrous ions present in the tissue. The aim of this study was to investigate the susceptibility of cod muscle pr...

  20. Bacteria-assisted preparation of nano α-Fe2O3 red pigment powders from waste ferrous sulfate

    International Nuclear Information System (INIS)

    Li, Xiang; Wang, Chuankai; Zeng, Yu; Li, Panyu; Xie, Tonghui; Zhang, Yongkui

    2016-01-01

    Highlights: • A route to prepare nano α-Fe 2 O 3 red pigment from waste ferrous sulfate is proposed. • Acidithiobacillus ferrooxidans is introduced for accelerating iron oxidation. • The particle size of synthetic α-Fe 2 O 3 is ranged from 22 nm to 86 nm. • The prepared nano α-Fe 2 O 3 red pigment fulfills ISO 1248-2006. - Abstract: Massive ferrous sulfate with excess sulfuric acid is produced in titanium dioxide industry each year, ending up stockpiled or in landfills as solid waste, which is hazardous to environment and in urgent demand to be recycled. In this study, waste ferrous sulfate was used as a second raw material to synthesize nano α-Fe 2 O 3 red pigment powders with a bacteria-assisted oxidation process by Acidithiobacillus ferrooxidans. The synthesis route, mainly consisting of bio-oxidation, precipitation and calcination, was investigated by means of titration, thermogravimetric analysis (TGA), X-ray diffraction (XRD), scanning electron microscope (SEM) and X-ray fluorescence (XRF) to obtain optimum conditions. Under the optimum conditions, nano α-Fe 2 O 3 red pigment powders contained 98.24 wt.% of Fe 2 O 3 were successfully prepared, with a morphology of spheroidal and particle size ranged from 22 nm to 86 nm and averaged at 45 nm. Moreover, the resulting product fulfilled ISO 1248-2006, the standards of iron oxide pigments.

  1. Study of the dose response of the system ferrous ammonium sulfate–sucrose–xylenol orange in acid aqueous solution

    International Nuclear Information System (INIS)

    Juarez-Calderon, J.M.; Negron-Mendoza, A.; Ramos-Bernal, S.

    2014-01-01

    An aqueous solution of ammonium ferrous sulfate–sucrose–xylenol orange in sulfuric acid (FSX) is proposed as a dosimetric system for the processes of gamma irradiation in a range between 0.3 and 6 Gy. This system is based on the indirect oxidation of ferrous ion by an organic compound (sucrose) to ferric ion and on the formation of a color complex of Fe 3+ in an acidic medium with xylenol orange (a dye). After gamma radiation, an observable change occurs in the color of the system. Irradiation was executed at three different temperatures (13 °C, 22 °C, and 40 °C). A spectrometric readout method at 585 nm was employed to evaluate the system's dose response. In all of the cases analyzed, the responses had a linear behavior, and a slight effect of irradiation temperature was observed. Post-irradiation response was also evaluated and showed the stability of the solutions 24 h after the irradiation. The results obtained suggest that FSX might be used as a dosimeter for low doses of gamma irradiation because it provides a stable signal, good reproducibility, and an accessible technique for analysis. - Highlights: • The system ferrous-sucrose-xylenol is reproducibility with less than 5% error. • The dosimeter has low cost and easy readout using UV-vis spectrometry, and the response is stable for several days. • The system proposed is suitable for low irradiation doses

  2. Current state of using radionuclides in mining and in metallurgy in the GDR

    International Nuclear Information System (INIS)

    Holzhey, J.

    1987-01-01

    Data is presented characterizing the range of the industrial use of tracer and radiometric methods in mining and metallurgy in the GDR in the years 1957-1975 and 1985. Of radiometric methods the most widely used were level gages, densimeters and fire detectors. Level gages were most widely used for measuring the height of filling of hoppers and silos. Radionuclide analytical methods are mainly used in the potassium industry for determining the content of potassium oxide. Natural radiation of 40 K radionuclides is used in the process. (Z.S.). 4 tabs., 2 refs

  3. Proceedings of the III International Congress of Mining and Metallurgy MINEMETAL 2016

    International Nuclear Information System (INIS)

    2016-10-01

    The III International Congress of Mining and Metallurgy was inaugurated at the Plaza América Convention Center in Varadero. Professionals from 16 countries come together to promote scientific exchange for sustainable mining and to make concrete future investments to boost the development of this important sector in Cuba. Among the topics that will occupy the agenda of these days of congress stand out the development of geology, new technological processes, advances in the application of zeolite, sustainable development and care of the environment.

  4. Accelerated Near-Threshold Fatigue Crack Growth Behavior of an Aluminum Powder Metallurgy Alloy

    Science.gov (United States)

    Piascik, Robert S.; Newman, John A.

    2002-01-01

    Fatigue crack growth (FCG) research conducted in the near threshold regime has identified a room temperature creep crack growth damage mechanism for a fine grain powder metallurgy (PM) aluminum alloy (8009). At very low DK, an abrupt acceleration in room temperature FCG rate occurs at high stress ratio (R = Kmin/Kmax). The near threshold accelerated FCG rates are exacerbated by increased levels of Kmax (Kmax less than 0.4 KIC). Detailed fractographic analysis correlates accelerated FCG with the formation of crack-tip process zone micro-void damage. Experimental results show that the near threshold and Kmax influenced accelerated crack growth is time and temperature dependent.

  5. Superplasticity in powder metallurgy aluminum alloys and composites

    International Nuclear Information System (INIS)

    Mishra, R.S.; Bieler, T.R.; Mukherjee, A.K.

    1995-01-01

    Superplasticity in powder metallurgy Al alloys and composites has been reviewed through a detailed analysis. The stress-strain curves can be put into 4 categories: classical well-behaved type, continuous strain hardening type, continuous strain softening type and complex type. The origin of these different types of is discussed. The microstructural features of the processed material and the role of strain have been reviewed. The role of increasing misorientation of low angle boundaries to high angle boundaries by lattice dislocation absorption is examined. Threshold stresses have been determined and analyzed. The parametric dependencies for superplastic flow in modified conventional aluminum alloys, mechanically alloyed alloys and Al alloy matrix composites is determined to elucidate the superplastic mechanism at high strain rates. The role of incipient melting has been analyzed. A stress exponent of 2, an activation energy equal to that for grain boundary diffusion and a grain size dependence of 2 generally describes superplastic flow in modified conventional Al alloys and mechanically alloyed alloys. The present results agree well with the predictions of grain boundary sliding models. This suggests that the mechanism of high strain rate superplasticity in the above-mentioned alloys is similar to conventional superplasticity. The shift of optimum superplastic strain rates to higher values is a consequence of microstructural refinement. The parametric dependencies for superplasticity in aluminum alloy matrix composites, however, is different. A true activation energy of superplasticity in aluminum alloy matrix composites, however, is different. A true activation energy of 313 kJ/mol best describes the composites having SiC reinforcements. The role of shape of the reinforcement (particle or whisker) and processing history is addressed. The analysis suggests that the mechanism for superplasticity in composites is interface diffusion controlled grain boundary sliding

  6. Analysis of effectiveness of the state industrial policy in ferrous metallurgy of Ukraine for the period 1996 – 2010 Анализ результативности государственной промышленной политики в черной металлургии Украины за 1996 – 2010 гг.

    Directory of Open Access Journals (Sweden)

    Denisov Konstantin V.

    2013-03-01

    Full Text Available The article contains analysis of results of realisation of legislative and regulatory acts, which determined development of the state industrial policy in ferrous metallurgy of Ukraine from 1996 till 2010. Analysis was conducted with the use of national statistics and international organisations: World Steel Association and International Steel Statistical Bureau. Analysis showed discrepancy of obtained results with the goals, which were set by the state within the framework of the branch industrial policy. This concerns development of the industrial and technological base, trade structure of production and export and also internal consumption of steel. Despite a number of benefits provided by the state, the technological level of the branch was low. Primary steel and semi-finished products dominate in the trade structure of production. Internal consumption of steel is limited and is lower than export indicators. The situation in other countries is quite opposite, due to which the article underlines a necessity to use their experience of branch industrial policy.В статье проведен анализ результатов реализации нормативно-правовых актов, которые определяли развитие государственной промышленной политики в черной металлургии Украины с 1996 по 2010 гг. Анализ проводился с использованием данных национальной статистики, а также международных организаций World Steel Association и Іnternational Steel Statistical Bureau. Анализ показал несоответствие полученных результатов тем целям, которые определялись государством в рамках отраслевой промышленной политики. Это касается

  7. NSF: A "Populist" Pattern in Metallurgy, Materials Research?

    Science.gov (United States)

    Shapley, Deborah

    1975-01-01

    Describes the testimony of a University of Virginia professor of applied science, who charged that the National Science Foundation grants disproportionately small funds to the best university departments in the field of metallurgy and materials, while preferentially funding middle-ranked departments. (MLH)

  8. Damage on 316LN stainless steel transformed by powder metallurgy

    International Nuclear Information System (INIS)

    Couturier, R.; Burlet, H.

    1998-01-01

    This study deals with the 316 LN stainless steel elaboration by powder metallurgy. This method allows the realization of structures in austenitic steel less affected by the thermal aging than the cast austenitic-ferritic components. The components are performed by the method of HIP (Hot Isostatic Pressing). Mechanical tests are provided to control mechanical properties

  9. Advances in Powder Metallurgy Soft Magnetic Composite Materials

    Directory of Open Access Journals (Sweden)

    Bureš R.

    2017-06-01

    Full Text Available Powder metallurgy has grown with the expansion of various industry. Automotive industry had the most strong influence. Today, more than 90% of PM products are used in the transportation industry. Development of new materials such as magnetic materials is expected to meet the new trends of automotive industry, electric and hybrid vehicles.

  10. Chemical and Metallurgy Research (CMR) Sample Tracking System Design Document

    International Nuclear Information System (INIS)

    Bargelski, C. J.; Berrett, D. E.

    1998-01-01

    The purpose of this document is to describe the system architecture of the Chemical and Metallurgy Research (CMR) Sample Tracking System at Los Alamos National Laboratory. During the course of the document observations are made concerning the objectives, constraints and limitations, technical approaches, and the technical deliverables

  11. The most essential tendencies in development of powder metallurgy

    International Nuclear Information System (INIS)

    Fedorchenko, I.M.

    1989-01-01

    A progress in the sphere of creation and application of new types of powder materials is characterized. The materials are as follows: structural, tribotechnical, composite, reinforced, precipitation-hardened, refractory, tool, materials based on light metals and others. A number of important problems whose solution will promote a further development of powder metallurgy are formulated

  12. Peculiarities of powder metallurgy of vanadium and its alloys

    International Nuclear Information System (INIS)

    Radomysel'skij, I.D.; Solntsev, V.P.; Evtushenko, O.V.

    1987-01-01

    Literature data on preparation of vanadium powder and powder materials on the vanadium base are generalized. Application of powder metallurgy engineering, allowing simulaneously to introduce practically any strengthening and solid-lubricating components as well as to alloy vanadium, permits undoubtedly to develop composite materials on the vanadium base

  13. Proceedings of the 1985 annual powder metallurgy conference

    International Nuclear Information System (INIS)

    Sanderow, H.I.; Giebelhausen, W.L.; Kulkarni, K.M.

    1985-01-01

    This book presents the papers given at a conference on powder metallurgy. Topics considered at the conference included yttrium oxide dispersion strengthened nickel alloy made by mechanical alloying, the optimal design of regression of the additive chromium oxide in aluminium oxide-molybdenum cermets, particle size distribution effects on the sintering of spherical tungsten, and heavy metal alloys containing 30% to 90% tungsten

  14. [Hygienic evaluation of risk factors on powder metallurgy production].

    Science.gov (United States)

    2011-01-01

    Complex hygienic, clinical, sociologic and epidemiologic studies revealed reliable relationship between work conditions and arterial hypertension, locomotory system disorders, monocytosis in powder metallurgy production workers. Findings are more probable cardiovascular and respiratory diseases, digestive tract diseases due to influence of lifestyle factors.

  15. Iron Metallurgy: Technical Terminology Bulletin. Terminotech, Vol. 2, No. 7.

    Science.gov (United States)

    General Electric Co. of Canada, Ltd., Montreal, Quebec.

    This issue of a bulletin of technological terminology is devoted to iron metallurgy. Various aspects of iron production are described in both French and English. An English-French dictionary of terms comprises the bulk of the document. Explanatory illustrations are appended. (JB)

  16. 21. Colloquium on metallurgy. Amorphous alloys and materials

    International Nuclear Information System (INIS)

    1979-01-01

    Twenty-two papers were presented at the 21st colloquium on metallurgy of amorphous alloys and materials. They deal with the applications, the various types, the preparation methods, the structure, the magnetic and thermodynamic properties and the structure defects of the amorphous materials [fr

  17. Review of the physical metallurgy of Alloy 718

    International Nuclear Information System (INIS)

    Keiser, D.D.; Brown, H.L.

    1976-02-01

    The physical metallurgy of Alloy 718 is updated to 1976 on the basis of a survey of post-1967 literature and current experimental data. Composition, microstructures, and mechanical properties are correlated with heat treatment parameters. The current state of understanding of phase stability, strengthening mechanisms, deformation modes, recovery, and recrystallization in this material is described

  18. Corrosion inhibition of powder metallurgy Mg by fluoride treatments.

    Science.gov (United States)

    Pereda, M D; Alonso, C; Burgos-Asperilla, L; del Valle, J A; Ruano, O A; Perez, P; Fernández Lorenzo de Mele, M A

    2010-05-01

    Pure Mg has been proposed as a potential degradable biomaterial to avoid both the disadvantages of non-degradable internal fixation implants and the use of alloying elements that may be toxic. However, it shows excessively high corrosion rate and insufficient yield strength. The effects of reinforcing Mg by a powder metallurgy (PM) route and the application of biocompatible corrosion inhibitors (immersion in 0.1 and 1M KF solution treatments, 0.1M FST and 1M FST, respectively) were analyzed in order to improve Mg mechanical and corrosion resistance, respectively. Open circuit potential measurements, polarization techniques (PT), scanning electrochemical microscopy (SECM) and electrochemical impedance spectroscopy (EIS) were performed to evaluate its corrosion behavior. SECM showed that the local current of attacked areas decreased during the F(-) treatments. The corrosion inhibitory action of 0.1M FST and 1M FST in phosphate buffered solution was assessed by PT and EIS. Under the experimental conditions assayed, 0.1M FST revealed better performance. X-ray photoelectron spectroscopy, energy dispersive X-ray and X-ray diffraction analyses of Mg(PM) with 0.1M FST showed the presence of KMgF(3) crystals on the surface while a MgF(2) film was detected for 1M FST. After fluoride inhibition treatments, promising results were observed for Mg(PM) as degradable metallic biomaterial due to its higher yield strength and lower initial corrosion rate than untreated Mg, as well as a progressive loss of the protective characteristics of the F(-)-containing film which ensures the gradual degradation process. Copyright (c) 2009 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.

  19. Ferrous-activated persulfate oxidation of arsenic(III) and diuron in aquatic system.

    Science.gov (United States)

    Zhou, Lei; Zheng, Wei; Ji, Yuefei; Zhang, Jinfeng; Zeng, Chao; Zhang, Ya; Wang, Qi; Yang, Xi

    2013-12-15

    In situ chemical oxidation (ISCO) can be an effective technology for the remediation of soil and groundwater polluted by organic and inorganic contaminants. This study investigated the oxidation of arsenic(III) (As(III)) and diuron using ferrous activated persulfate-based ISCO. The results indicated that Fe(II)/persulfate oxidation could be an effective method to oxidize As(III) and diuron. Effects of pH, S2O8(2-) and Fe(II) amounts on the destruction of As(III) and diuron were examined in batch experiments. Acidic conditions favored the removal of As(III) and diuron. Four chelating agents, citric acid (CA), Na2S2O3, diethylene triamine pentaacetic acid (DTPA) and ethylene diamine tetraacetic acid disodium (EDTA-Na2) were used in attempt to maintain the quantity of ferrous ion in solution. In our experiments, CA and Na2S2O3 were found to be more effective than DTPA and EDTA-Na2. Our results also revealed a widely practical prospect of inorganic chelating agent Na2S2O3. Hydroxyl and sulfate radical were determined to play key roles in the oxidation process by using ethanol and tertiary butanol as molecular probes. Oxidation of As(III) yielded As(V) via the electron-transfer reaction. In the oxidation process of diuron, a stepwise nucleophilic substitution of chlorine by hydroxyl and a stepwise oxidation process of the methyl on the dimethylurea group by hydroxyl and sulfate radical were proposed. Copyright © 2013 Elsevier B.V. All rights reserved.

  20. Ferrous-activated persulfate oxidation of arsenic(III) and diuron in aquatic system

    International Nuclear Information System (INIS)

    Zhou, Lei; Zheng, Wei; Ji, Yuefei; Zhang, Jinfeng; Zeng, Chao; Zhang, Ya; Wang, Qi; Yang, Xi

    2013-01-01

    Highlights: • Effective oxidation of As(III)/diuron is achieved by Fe(II)-activated persulfate. • Hydroxyl and sulfate radical play important roles in As(III) and diuron oxidation. • CA and Na 2 S 2 O 3 are efficient and environmental friendly chelating agents. • DFT calculation is found to be useful for degradation products prediction. -- Abstract: In situ chemical oxidation (ISCO) can be an effective technology for the remediation of soil and groundwater polluted by organic and inorganic contaminants. This study investigated the oxidation of arsenic(III) (As(III)) and diuron using ferrous activated persulfate-based ISCO. The results indicated that Fe(II)/persulfate oxidation could be an effective method to oxidize As(III) and diuron. Effects of pH, S 2 O 8 2− and Fe(II) amounts on the destruction of As(III) and diuron were examined in batch experiments. Acidic conditions favored the removal of As(III) and diuron. Four chelating agents, citric acid (CA), Na 2 S 2 O 3 , diethylene triamine pentaacetic acid (DTPA) and ethylene diamine tetraacetic acid disodium (EDTA-Na 2 ) were used in attempt to maintain the quantity of ferrous ion in solution. In our experiments, CA and Na 2 S 2 O 3 were found to be more effective than DTPA and EDTA-Na 2 . Our results also revealed a widely practical prospect of inorganic chelating agent Na 2 S 2 O 3 . Hydroxyl and sulfate radical were determined to play key roles in the oxidation process by using ethanol and tertiary butanol as molecular probes. Oxidation of As(III) yielded As(V) via the electron-transfer reaction. In the oxidation process of diuron, a stepwise nucleophilic substitution of chlorine by hydroxyl and a stepwise oxidation process of the methyl on the dimethylurea group by hydroxyl and sulfate radical were proposed

  1. Abnormal flow behavior and necklace microstructure of powder metallurgy superalloys with previous particle boundaries (PPBs)

    Energy Technology Data Exchange (ETDEWEB)

    Ning, Yongquan, E-mail: luckyning@nwpu.edu.cn [School of Materials Science and Engineering, Northwestern Polytechnical University, Xi’an 710072 (China); Zhou, Cong; Liang, Houquan [School of Materials Science and Engineering, Northwestern Polytechnical University, Xi’an 710072 (China); Fu, M.W., E-mail: mmmwfu@polyu.edu.hk [Department of Mechanical Engineering, The Hong Kong Polytechnic University, Hung Hom, Kowloon, Hong Kong (China)

    2016-01-15

    Powder metallurgy (P/M) has been introduced as an innovative process to manufacture high performance components with fine, homogenous and segregation-free microstructure. Unfortunately, previous particle boundary (PPB) precipitated during the powder metallurgy process. Since undesirable PPB is detrimental to mechanical properties, hot extrusion or/and isothermal forging are needed. In present research, isothermal compression tests were conducted on P/M FGH4096 superalloys with typical PPBs. Abnormal flow behavior during high-speed deformation has been quantitatively investigated. Caused by the competition mechanism between work-hardening and dynamic-softening, abnormal flow behaves typical four stages (viz., work-hardening, stable, softening and steady). Microstructure observation for hardening or/and softening mechanism has been investigated. Meanwhile, necklace microstructure was observed by scanning electron microscope, and the grain fraction analysis was performed by using electron backscatter diffraction. Transmission electron microscopy was used for characterizing the boundary structure. Necklace microstructural mechanism for processing P/M superalloys has been developed, and the dynamic recrystallization model has also been conducted. Bulge–corrugation model is the primary nucleation mechanism for P/M superalloys with PPBs. When PPB is entirely covered with new grains, necklace microstructure has formed. Bulge–corrugation mechanism can repeatedly take place in the following necklace DRX.

  2. Characterization of aluminum/steel components from recycled swarf using the powder metallurgy as technique

    International Nuclear Information System (INIS)

    Souza, V.E.S.; Masieiro, F.R.S.; Lourenco, J.M.; Felipe, R.C.T.S.

    2009-01-01

    Full text: The powder metallurgy process consists to produce metallic or ceramic components through pressure in a powder mass. These components will be submitted to a sintering temperature in order to consolidate them and then improve their mechanical proprieties. The industry is responsible for the swarf generation from different manufacture process. This paper has main goal the reutilization of aluminum and steel swarf using the powder metallurgy as technique. The methodology used in this work consists to compact Al 6060 plus steel SAE 1045 as reinforce material at 250MPa, 400MPa and 600MPa. The composition about these compacted will be 30%, 40%, 50% of steel into aluminum matrix. In this way will be analyze the hardness as function of the compressibility and quantity of steel. The samples will be processed at 500°C during 45 minutes using a resistive furnace in a hydrogen atmosphere. Micrographs of the sintered samples will be obtained by using a Scanning Electron Microscope and Optic Microscope. X-rays diffraction will be also used to characterize the phases found to due diffusivity between the steel and aluminum. (author)

  3. A method for the separation of non-ferrous metal containing particles from a particle stream

    NARCIS (Netherlands)

    Van der Weijden, R.D.; Rem, P.C.

    2004-01-01

    The invention relates to a method for the recovery of non-ferrous metal-comprising particles from a particle stream. According to the invention, the particle stream is put onto a conveyor belt in the form of a monolayer such that with the aid of a liquid, at least the non-ferrous metal comprising

  4. KINETICS OF THE OXIDATION OF FERROUS CHELATES OF EDTA AND HEDTA IN AQUEOUS-SOLUTION

    NARCIS (Netherlands)

    WUBS, HJ; BEENACKERS, AACM

    1993-01-01

    The kinetics of the reaction of oxygen with ferrous chelates of EDTA and HEDTA was studied in a stirred cell reactor under industrial conditions. The temperature was varied from 20 to 60-degrees-C and the concentration of the ferrous chelate ranged from 0 to 100 mol/m3. The initial pH was 7.5. Under

  5. A procedure for oxidation during the acid leaching of non-ferrous ores, particularly uranium ores

    International Nuclear Information System (INIS)

    Zubcek, L.; Baloun, S.; Martinek, K.; Vebr, Z.; Krepelka, J.; Lasica, S.

    1989-01-01

    It is suggested that dust from the production of ferroalloys of manganese, particularly ferrosilicomanganese and ferromanganese, can be conveniently used for oxidation during the acid leaching of non-ferrous ores, particularly uranium ores. This dust contains 30 to 40% oxides of manganese, about one-half of this is MnO 2 . Iron in the dust is present in the trivalent form, and the dust is pefectly dry. The conventional grinding of oxidants for the ore processing is eliminated, the dust being available in particle size below 0.2 mm. The dust is added in amounts of 5 to 100 kg per ton of the ore, and the suspension is typically heated at 115 degC for 3.5 hr. (P.A.)

  6. Anionic Surfactant as a Corrosion Inhibitor for Synthesized Ferrous Alloy in Acidic Solution

    Directory of Open Access Journals (Sweden)

    Farida Kellou-Kerkouche

    2013-01-01

    Full Text Available The effect of temperature on the corrosion behaviour of a synthesized iron-based alloy in 1 N sulphuric acid solution has been examined by means of three electrochemical techniques. Thereafter, we studied the influence of an anionic surfactant (sodium dodecyl benzene sulfonate at various concentrations on the electrochemical behaviour of the ferrous alloy. The obtained results show that the temperature increase reduced the performance of the used alloy, in the acidic environment. Otherwise, the surfactant inhibits the alloy dissolution in the sulphuric acid, through its adsorption on the metal surface without modifying the mechanism of corrosion process. We also noticed that the highest inhibition effect is obtained at a concentration above its critical micelle concentration (CMC. Langmuir adsorption isotherm fits well with the experimental data.

  7. Iron oxide and hydroxide precipitation from ferrous solutions and its relevance to Martian surface mineralogy

    Science.gov (United States)

    Posey-Dowty, J.; Moskowitz, B.; Crerar, D.; Hargraves, R.; Tanenbaum, L.

    1986-01-01

    Experiments were performed to examine if the ubiquitousness of a weak magnetic component in all Martian surface fines tested with the Viking Landers can be attributed to ferric iron precipitation in aqueous solution under oxidizing conditions at neutral pH. Ferrous solutions were mixed in deionized water and various minerals were added to separate liquid samples. The iron-bearing additives included hematite, goethite, magnetite, maghemite, lepidocrocite and potassium bromide blank at varying concentrations. IR spectroscopic scans were made to identify any precipitates resulting from bubbling oxygen throughout the solutions; the magnetic properties of the precipitates were also examined. The data indicated that the lepidocrocite may have been preferentially precipitated, then aged to maghemite. The process would account for the presumed thin residue of maghemite on the present Martian surface, long after abundant liquid water on the Martian surface vanished.

  8. Iron oxide and hydroxide precipitation from ferrous solutions and its relevance to Martian surface mineralogy

    International Nuclear Information System (INIS)

    Posey-Dowty, J.; Moskowitz, B.; Crerar, D.; Hargraves, R.; Tanenbaum, L.

    1986-01-01

    Experiments were performed to examine if the ubiquitousness of a weak magnetic component in all Martian surface fines tested with the Viking Landers can be attributed to ferric iron precipitation in aqueous solution under oxidizing conditions at neutral pH. Ferrous solutions were mixed in deionized water and various minerals were added to separate liquid samples. The iron-bearing additives included hematite, goethite, magnetite, maghemite, lepidocrocite and potassium bromide blank at varying concentrations. IR spectroscopic scans were made to identify any precipitates resulting from bubbling oxygen throughout the solutions; the magnetic properties of the precipitates were also examined. The data indicated that the lepidocrocite may have been preferentially precipitated, then aged to maghemite. The process would account for the presumed thin residue of maghemite on the present Martian surface, long after abundant liquid water on the Martian surface vanished. 40 references

  9. Technology study on removal of Ra, U, Mn and F from the acid wastewater of uranium mining and metallurgy

    International Nuclear Information System (INIS)

    Wu Yongyong; Zhong Pingru; Wang Gaoshan

    2014-01-01

    The laboratory study for decreasing the concentration of Ra, U, Mn and F ions in acid wastewater of uranium mining and metallurgy was investigated based on lime neutralization-precipitation technology. The technological flowsheet was composed of removing radium by barium chloride, manganese by air aeration and fluorin by aluminum sulfate, and the quality of the disposed effluent could be accorded with the discharge criteria defined by the state, as the neutralization conditions of pH just being 8.5. Furthermore, the lower precipitation pH value can effectively decrease sediment volume, and reduce the subsequent processing pressures. The technological methods were viable and universally applicable for uranium mining and metallurgy wastewater purification. (authors)

  10. Metallurgy of high-silicon steel parts produced using Selective Laser Melting

    International Nuclear Information System (INIS)

    Garibaldi, Michele; Ashcroft, Ian; Simonelli, Marco; Hague, Richard

    2016-01-01

    The metallurgy of high-silicon steel (6.9%wt.Si) processed using Selective Laser Melting (SLM) is presented for the first time in this study. High-silicon steel has great potential as a soft magnetic alloy, but its employment has been limited due to its poor workability. The effect of SLM-processing on the metallurgy of the alloy is investigated in this work using microscopy, X-Ray Diffraction (XRD) and Electron Backscatter Diffraction (EBSD). XRD analysis suggests that the SLM high-silicon steel is a single ferritic phase (solid solution), with no sign of phase ordering. This is expected to have beneficial effects on the material properties, since ordering has been shown to make silicon steels more brittle and electrically conductive. For near-fully dense samples, columnar grains with a high aspect ratio and oriented along the build direction are found. Most importantly, a <001> fibre-texture along the build direction can be changed into a cube-texture when the qualitative shape of the melt-pool is altered (from shallow to deep) by increasing the energy input of the scanning laser. This feature could potentially open the path to the manufacture of three-dimensional grain-oriented high-silicon steels for electromechanical applications.

  11. Microstructural and electrical investigation of Cu-Ni-Cr alloys obtained by powder metallurgy method

    International Nuclear Information System (INIS)

    Carrio, Juan A.G.; Carvalhal, M.A.; Ayabe, L.M.; Monteiro, W.A.

    2009-01-01

    The aim of this work, using the powder metallurgy process, is to synthesize metallic alloys with high mechanical strength and high electric conductivity, after melting optimizing and thermal treatments. The Cu-Ni-Cr (wt%) alloys are characterized in their mechanical and electrical properties as well as the obtained microstructure. Through the process of powder metallurgy, contacts and structural parts can be obtained. The alloys elements are added to copper with the intention to improve their strength, ductility and thermal stability, without causing considerable damages in their form, electrical and thermal conductivity, and corrosion resistance. The metallic powders were mixed for a suitable time and then they were pressed in a cold uniaxial pressing (1000 kPa). Afterwards, the specimens were sintered in temperatures varying from 700 up to 800 deg C under vacuum. At last, the samples were homogenized at 550 deg C under vacuum, for special times. The comparative analysis is based on the sintered density, densification parameter, hardness, macrostructures and microstructures of the samples. The alloys were characterized by optical microscopy, X-rays powder diffraction, electrical conductivity and Vickers hardness. (author)

  12. Fractionation study in bioleached metallurgy wastes using six-step sequential extraction.

    Science.gov (United States)

    Krasnodebska-Ostrega, Beata; Pałdyna, Joanna; Kowalska, Joanna; Jedynak, Łukasz; Golimowski, Jerzy

    2009-08-15

    The stored metallurgy wastes contain residues from ore processing operations that are characterized by relatively high concentrations of heavy metals. The bioleaching process makes use of bacteria to recover elements from industrial wastes and to decrease potential risk of environmental contamination. Wastes were treated by solutions containing bacteria. In this work, the optimized six-stage sequential extraction procedure was applied for the fractionation of Ni, Cr, Fe, Mn, Cu and Zn in iron-nickel metallurgy wastes deposited in Southern Poland (Szklary). Fractionation and total concentrations of elements in wastes before and after various bioleaching treatments were studied. Analyses of the extracts were performed by ICP-MS and FAAS. To achieve the most effective bioleaching of Zn, Cr, Ni, Cu, Mn, Fe the usage of both autotrophic and heterotrophic bacteria in sequence, combined with flushing of the residue after bioleaching is required. 80-100% of total metal concentrations were mobilized after the proposed treatment. Wastes treated according to this procedure could be deposited without any risk of environmental contamination and additionally the metals could be recovered for industrial purposes.

  13. Reuse of scrap of Al and steel SAE 1045 in metal composite as alternative of recycling route powder metallurgy

    International Nuclear Information System (INIS)

    Souza, V.E.S.; Masieiro, F.R.S.; Lourenco, J.M.; Felipe, R.C.T.S.

    2009-01-01

    Full text: The process of powder metallurgy in the production of parts through application of pressure on the selected ceramic or metal powders, which are subjected to a temperature of sintering for to occur consolidation of the components. The metal-mechanical industry is responsible for the generation of inputs from their manufacturing processes. This work aims to re-use of chips of Al and SAE 1045 steel by powder metallurgy of this is a viable and effective. This work is in the manufacture of a composite using Al 6060 metal matrix and steel 1045 as reinforcement (30%, 40%, 50%), under different compaction pressures (250MPa, 400MPa and 600MPa), analyzing the influence of compressibility in hardness of the compressed. The samples were sintered at a temperature of 500 ° C in an oven using resistive atmosphere of hydrogen for 45 minutes. After the procedures of the powder metallurgy technique were analyzed of the optical microscopy, x-ray diffraction, MEV and Rockwell hardness, which was found to be evaluated as not diffusibility between the steel and aluminum. (author)

  14. Testing of electroformed deposited iridium/powder metallurgy rhenium rockets

    Science.gov (United States)

    Reed, Brian D.; Dickerson, Robert

    1996-01-01

    High-temperature, oxidation-resistant chamber materials offer the thermal margin for high performance and extended lifetimes for radiation-cooled rockets. Rhenium (Re) coated with iridium (Ir) allow hours of operation at 2200 C on Earth-storable propellants. One process for manufacturing Ir/Re rocket chambers is the fabrication of Re substrates by powder metallurgy (PM) and the application of Ir coatings by using electroformed deposition (ED). ED Ir coatings, however, have been found to be porous and poorly adherent. The integrity of ED Ir coatings could be improved by densification after the electroforming process. This report summarizes the testing of two 22-N, ED Ir/PM Re rocket chambers that were subjected to post-deposition treatments in an effort to densify the Ir coating. One chamber was vacuum annealed, while the other chamber was subjected to hot isostatic pressure (HIP). The chambers were tested on gaseous oxygen/gaseous hydrogen propellants, at mixture ratios that simulated the oxidizing environments of Earth-storable propellants. ne annealed ED Ir/PM Re chamber was tested for a total of 24 firings and 4.58 hr at a mixture ratio of 4.2. After only 9 firings, the annealed ED Ir coating began to blister and spall upstream of the throat. The blistering and spalling were similar to what had been experienced with unannealed, as-deposited ED Ir coatings. The HIP ED Ir/PM Re chamber was tested for a total of 91 firings and 11.45 hr at mixture ratios of 3.2 and 4.2. The HIP ED Ir coating remained adherent to the Re substrate throughout testing; there were no visible signs of coating degradation. Metallography revealed, however, thinning of the HIP Ir coating and occasional pores in the Re layer upstream of the throat. Pinholes in the Ir coating may have provided a path for oxidation of the Re substrate at these locations. The HIP ED Ir coating proved to be more effective than vacuum annealed and as-deposited ED Ir. Further densification is still required to

  15. A Metallurgical Investigation of the Direct Energy Deposition Surface Repair of Ferrous Alloys

    Science.gov (United States)

    Marya, Manuel; Singh, Virendra; Hascoet, Jean-Yves; Marya, Surendar

    2018-02-01

    Among additive manufacturing (AM) processes, the direct energy deposition (DED) by laser is explored to establish its applicability for the repair of ferrous alloys such as UNS G41400 low-alloy steel, UNS S41000 martensitic stainless steel, UNS S17400 precipitation-strengthened martensitic stainless steel, and UNS S32750 super-duplex stainless steel. Unlike plating, thermal spray, and conventional cladding weld, DED laser powder deposition offers potential advantages, e.g., thin deposits, limited dilutions, narrow heat-affected zones (HAZ), potentially improved surface properties. In this investigation, all AM deposits were completed with an IREPA CLAD™ system using a powder feed of UNS N06625, an alloy largely selected for its outstanding corrosion resistance. This investigation first addresses topological aspects of AM deposits (including visual imperfections) before focusing on changes in microstructure, microhardness, chemical composition across AM deposits and base materials. It has been established that dense, uniform, hard ( 300 HVN), crack-free UNS N06625-compliant AM deposits of fine dendritic microstructures are reliably produced. However, except for the UNS S32750 steel, a significant martensitic hardening was observed in the HAZs of UNS G41400 ( 650 HVN), UNS S41000 ( 500 HVN), and UNS S17400 ( 370 HVN). In summary, this investigation demonstrates that the DED laser repair of ferrous parts with UNS N06625 may restore damaged surfaces, but it also calls for cautions and complementary investigations for alloys experiencing a high HAZ hardening, for which industry standard recommendations are exceeded and lead to an increased risk of delayed cracking in corrosive environments.

  16. Active removal of ibuprofen by Money plant enhanced by ferrous ions.

    Science.gov (United States)

    Chehrenegar, Behdad; Hu, Jiangyong; Ong, Say Leong

    2016-02-01

    In this study, the removal of ibuprofen (IBP), a pharmaceutical compound, from aqueous media by Money plant (Epipremnum aureum) was investigated. The effect of ferrous iron (Fe(2+)) on enhancing the IBP removal rate was also analyzed. The first-order removal rate constants showed higher values for lower IBP initial concentrations in the range of 0.20-0.28 d(-1) for an initial concentration of 125 μg L(-1) to 0.03-0.13 d(-1) for an initial concentration of 1000 μg L(-1). Introducing ferrous iron to the aqueous media enhanced the first-order removal rate constant up to 6.5 times in a 3 d time period. Along with the removal of IBP from the media, the endogenous concentration of H2O2 also decreased presumably by the production of hydroxyl radical (·OH). Reduction in the endogenous H2O2 concentration was recorded to be 38% and 98% in the absence and presence of Fe(2+) respectively in the first day and the H2O2 level remained considerably low until day 7 which then gradually increased slightly. Simultaneous reduction of IBP and endogenous H2O2 concentration could be due to the reaction of IBP with ·OH and presumably ·OH production itself accelerated via Fenton reaction. In addition, presence of sodium bicarbonate (NaHCO3) as ·OH scavenger in the system showed reduction of first-order removal rate constant from 1.30 d(-1) to 0.07 d(-1) which could be a possible evidence of biological advanced oxidation process which is believed to play an important role in phytoremediation. Copyright © 2015 Elsevier Ltd. All rights reserved.

  17. Powder Metallurgy Fabrication of Molybdenum Accelerator Target Disks

    Energy Technology Data Exchange (ETDEWEB)

    Lowden, Richard Andrew [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Kiggans Jr., James O. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Nunn, Stephen D. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Parten, Randy J. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)

    2015-07-01

    Powder metallurgy approaches for the fabrication of accelerator target disks are being examined to support the development of Mo-99 production by NorthStar Medical Technologies, LLC. An advantage of powder metallurgy is that very little material is wasted and, at present, dense, quality parts are routinely produced from molybdenum powder. The proposed targets, however, are thin wafers, 29 mm in diameter with a thickness of 0.5 mm, with very stringent dimensional tolerances. Although tooling can be machined to very high tolerance levels, the operations of powder feed, pressing and sintering involve complicated mechanisms, each of which affects green density and shrinkage, and therefore the dimensions and shape of the final product. Combinations of powder morphology, lubricants and pressing technique have been explored to produce target disks with minimal variations in thickness and little or no distortion. In addition, sintering conditions that produce densities for optimum target dissolvability are being determined.

  18. Near-Net Shape Powder Metallurgy Rhenium Thruster

    Science.gov (United States)

    Leonhardt, Todd; Hamister, Mark; Carlen, Jan C.; Biaglow, James; Reed, Brian

    2001-01-01

    This paper describes the development of a method to produce a near-net shape (NNS) powder metallurgy (PM) rhenium combustion chamber of the size 445 N (100 lbf) used in a high performance liquid apogee engine. These engines are used in low earth Orbit and geostationary orbit for satellite positioning systems. The developments in near-net shape powder metallurgy rhenium combustion chambers reported in this paper will reduce manufacturing cost of the rhenium chambers by 25 percent, and reduce the manufacturing time by 30 to 40 percent. The quantity of rhenium metal powder used to produce a rhenium chamber is reduced by approximately 70 percent and the subsequent reduction in machining schedule and costs is nearly 50 percent.

  19. A survivability model for ejection of green compacts in powder metallurgy technology

    Directory of Open Access Journals (Sweden)

    Payman Ahi

    2012-01-01

    Full Text Available Reliability and quality assurance have become major considerations in the design and manufacture of today’s parts and products. Survivability of green compact using powder metallurgy technology is considered as one of the major quality attributes in manufacturing systems today. During powder metallurgy (PM production, the compaction conditions and behavior of the metal powder dictate the stress and density distribution in the green compact prior to sintering. These parameters greatly influence the mechanical properties and overall strength of the final component. In order to improve these properties, higher compaction pressures are usually employed, which make unloading and ejection of green compacts more challenging, especially for the powder-compacted parts with relatively complicated shapes. This study looked at a mathematical survivability model concerning green compact characteristics in PM technology and the stress-strength failure model in reliability engineering. This model depicts the relationship between mechanical loads (stress during ejection, experimentally determined green strength and survivability of green compact. The resulting survivability is the probability that a green compact survives during and after ejection. This survivability model can be used as an efficient tool for selecting the appropriate parameters for the process planning stage in PM technology. A case study is presented here in order to demonstrate the application of the proposed survivability model.

  20. Porous titanium scaffolds fabricated using a rapid prototyping and powder metallurgy technique.

    Science.gov (United States)

    Ryan, Garrett E; Pandit, Abhay S; Apatsidis, Dimitrios P

    2008-09-01

    One of the main issues in orthopaedic implant design is the fabrication of scaffolds that closely mimic the biomechanical properties of the surrounding bone. This research reports on a multi-stage rapid prototyping technique that was successfully developed to produce porous titanium scaffolds with fully interconnected pore networks and reproducible porosity and pore size. The scaffolds' porous characteristics were governed by a sacrificial wax template, fabricated using a commercial 3D-printer. Powder metallurgy processes were employed to generate the titanium scaffolds by filling around the wax template with titanium slurry. In the attempt to optimise the powder metallurgy technique, variations in slurry concentration, compaction pressure and sintering temperature were investigated. By altering the wax design template, pore sizes ranging from 200 to 400 microm were achieved. Scaffolds with porosities of 66.8 +/- 3.6% revealed compression strengths of 104.4+/-22.5 MPa in the axial direction and 23.5 +/- 9.6 MPa in the transverse direction demonstrating their anisotropic nature. Scaffold topography was characterised using scanning electron microscopy and microcomputed tomography. Three-dimensional reconstruction enabled the main architectural parameters such as pore size, interconnecting porosity, level of anisotropy and level of structural disorder to be determined. The titanium scaffolds were compared to their intended designs, as governed by their sacrificial wax templates. Although discrepancies in architectural parameters existed between the intended and the actual scaffolds, overall the results indicate that the porous titanium scaffolds have the properties to be potentially employed in orthopaedic applications.

  1. Minimization of radioactive solid wastes from uranium mining and metallurgy

    International Nuclear Information System (INIS)

    Zhang Xueli; Xu Lechang; Wei Guangzhi; Gao Jie; Wang Erqi

    2010-01-01

    The concept and contents of radioactive waste minimization are introduced. The principle of radioactive waste minimization involving administration optimization, source reduction, recycling and reuse as well as volume reduction are discussed. The strategies and methods to minimize radioactive solid wastes from uranium mining and metallurgy are summarized. In addition, the benefit from its application of radioactive waste minimization is analyzed. Prospects for the research on radioactive so-lid waste minimization are made in the end. (authors)

  2. Microstructure and Aging of Powder-Metallurgy Al Alloys

    Science.gov (United States)

    Blackburn, L. B.

    1987-01-01

    Report describes experimental study of thermal responses and aging behaviors of three new aluminum alloys. Alloys produced from rapidly solidified powders and contain 3.20 to 5.15 percent copper, 0.24 to 1.73 percent magnesium, 0.08 to 0.92 percent iron, and smaller amounts of manganese, nickel, titanium, silicon, and zinc. Peak hardness achieved at lower aging temperatures than with standard ingot-metallurgy alloys. Alloys of interest for automobile, aircraft, and aerospace applications.

  3. Powder-metallurgy superalloy strengthened by a secondary gamma phase.

    Science.gov (United States)

    Kotval, P. S.

    1971-01-01

    Description of experiments in which prealloyed powders of superalloy compositions were consolidated by extrusion after the strengthening by precipitation of a body-centered tetragonal gamma secondary Ni3 Ta phase. Thin foil electron microscopy showed that the mechanical properties of the resultant powder-metallurgy product were correlated with its microstructure. The product exhibited high strength at 1200 F without loss of ductility, after thermomechanical treatment and aging.

  4. Fabrication of metal matrix composites by powder metallurgy: A review

    Science.gov (United States)

    Manohar, Guttikonda; Dey, Abhijit; Pandey, K. M.; Maity, S. R.

    2018-04-01

    Now a day's metal matrix components are used in may industries and it finds the applications in many fields so, to make it as better performable materials. So, the need to increase the mechanical properties of the composites is there. As seen from previous studies major problem faced by the MMC's are wetting, interface bonding between reinforcement and matrix material while they are prepared by conventional methods like stir casting, squeeze casting and other techniques which uses liquid molten metals. So many researchers adopt PM to eliminate these defects and to increase the mechanical properties of the composites. Powder metallurgy is one of the better ways to prepare composites and Nano composites. And the major problem faced by the conventional methods are uniform distribution of the reinforcement particles in the matrix alloy, many researchers tried to homogeneously dispersion of reinforcements in matrix but they find it difficult through conventional methods, among all they find ultrasonic dispersion is efficient. This review article is mainly concentrated on importance of powder metallurgy in homogeneous distribution of reinforcement in matrix by ball milling or mechanical milling and how powder metallurgy improves the mechanical properties of the composites.

  5. Mechanical and microstructural characterization of powder metallurgy CoCrNi medium entropy alloy

    Czech Academy of Sciences Publication Activity Database

    Moravčík, I.; Čížek, Jan; Kováčová, Z.; Nejezchlebová, J.; Kitzmantel, M.; Neubauer, E.; Kuběna, Ivo; Horník, Vít; Dlouhý, I.

    2017-01-01

    Roč. 701, July (2017), s. 370-380 ISSN 0921-5093 Institutional support: RVO:61389021 ; RVO:68081723 Keywords : tensile test * mechanical alloying * plastic ity * mechanical characterization * powder metallurgy Subject RIV: JG - Metallurgy; JG - Metallurgy (UFM-A) OBOR OECD: Materials engineering; Materials engineering (UFM-A) Impact factor: 3.094, year: 2016 https://www.sciencedirect.com/science/article/pii/S0921509317308535

  6. Precipitation in Powder Metallurgy, Nickel Base Superalloys: Review of Modeling Approach and Formulation of Engineering (Postprint)

    Science.gov (United States)

    2016-12-01

    AFRL-RX-WP-JA-2016-0333 PRECIPITATION IN POWDER- METALLURGY , NICKEL-BASE SUPERALLOYS: REVIEW OF MODELING APPROACH AND FORMULATION OF...PRECIPITATION IN POWDER- METALLURGY , NICKEL- BASE SUPERALLOYS: REVIEW OF MODELING APPROACH AND FORMULATION OF ENGINEERING (POSTPRINT) 5a...and kinetic parameters required for the modeling of γ′ precipitation in powder- metallurgy (PM), nickel-base superalloys are summarized. These

  7. A Comparison of the Plastic Flow Response of a Powder Metallurgy Nickel Base Superalloy (Postprint)

    Science.gov (United States)

    2017-04-01

    AFRL-RX-WP-JA-2017-0225 A COMPARISON OF THE PLASTIC-FLOW RESPONSE OF A POWDER- METALLURGY NICKEL-BASE SUPERALLOY (POSTPRINT) S.L...COMPARISON OF THE PLASTIC-FLOW RESPONSE OF A POWDER- METALLURGY NICKEL-BASE SUPERALLOY (POSTPRINT) 5a. CONTRACT NUMBER IN-HOUSE 5b. GRANT...behavior at hot-working temperatures and strain rates of the powder- metallurgy superalloy LSHR was determined under nominally-isothermal and transient

  8. The effect of powder metallurgy process parameters on mechanical ...

    African Journals Online (AJOL)

    International Journal of Engineering, Science and Technology. Journal Home · ABOUT THIS JOURNAL · Advanced Search · Current Issue · Archives · Journal Home > Vol 3, No 9 (2011) >. Log in or Register to get access to full text downloads.

  9. Characterization of naturally occurring radioactive materials and Cobald-60 contaminated ferrous scraps from steel industries

    International Nuclear Information System (INIS)

    Chao, H.E.; Chiu, H.S.; Hunga, J.Y.; His, H.W.; Chen, Y.B.

    2002-01-01

    Since the occurrence of radioactively contaminated rebar incident in 1992, steel industries in Taiwan were encouraged by Atomic Energy Council (AEC) to install portal monitor to detect the abnormal radiation in shipments of metal scrap feed. From 1994 through 1999, there were 53 discoveries of radioactivity in ferrous scraps by steel companies. These include 15 orphan radioactive sources, 16 cobalt-60 contaminated rebars, 20 Naturally Occurring Radioactive Material (NORM) contaminated scraps, and two unknowns. Most NORM-contaminated scraps were from abroad. The NORM and cobalt-60 contaminated scraps were taken from the steel mills and analyzed in laboratory. The analytical results of scales and sludge sampled from NORM-contaminated scraps combining with the circumstantial evidences indicate that five possible industrial processes may be involved. They are oil production and treatment, heavy mineral sand benefication and rare earth processing, copper mining and processing, recovery of ammonium chloride by lime adsorption in Ammonium-soda process, and tailing of uranium enrichment process. The cobalt-60 activity and trace elements concentrations of contaminated rebars confirm that all of them were produced domestically in the period from Oct. 1982 to Jan. 1983, when the cobalt-60 sources were lost and entered the electric arc furnace to produce the contaminated rebars. (author)

  10. Thermo-ecological cost (TEC evaluation of metallurgical processes

    Directory of Open Access Journals (Sweden)

    W. Stanek

    2015-01-01

    Full Text Available Metallurgy represents a complex production system of fuel and mineral non-renewable resources transformation. The effectiveness of resource management in metallurgical chains depends on the applied ore grade and on the irreversibility of components of the system. TEC can be applied to measure the influence of metallurgy on the depletion of natural resources. The paper discusses the possibility of application of TEC in metallurgy and presents illustrative example concerning blast-furnace process.

  11. Metallurgy of continuous filamentary A15 superconductors

    International Nuclear Information System (INIS)

    Suenaga, M.

    1980-01-01

    The early history of the bronze process is recapitulated and modifications to the process which have since followed are described. The metallurgical principles, which are involved in the process, are described including the kinetics of the compound growth, the effects of additives on the growth, etc. The superconducting properties of these compounds are also discussed. The influence of metallurgical variables on the superconducting properties is discussed in detail. In discussing the superconducting current densities in these compounds, limits in applicability of existing magnetic-flux-pinning models are also treated as well as methods for determining critical magnetic fields

  12. Microstructure and properties of powder metallurgy (PM) high alloy tool steels

    International Nuclear Information System (INIS)

    Wojcieszynski, A.L.; Eisen, W.B.; Dixon, R.B.

    1998-01-01

    Particle metallurgy (PM) processing is currently the primary manufacturing method used to produce advanced high alloy tool steel compositions for use in industrial tooling applications. This process involves gas atomization of the pre-alloyed melt to form spherical powders and consolidation by HIP to full density. The HIP product may be used directly in select applications, but is usually subjected to additional forging to improve properties and produce a wide range of bar and plate sizes. Compared to ingot-cast tool steels, PM tool steels have very homogeneous microstructures with very fine carbide and sulfide size distributions, free from carbide banding, which results in improved machinability, grindability, and mechanical properties. In addition, this technology enables the development of advanced tool steel compositions which could not be economically produced by conventional steelmaking. (author)

  13. Separating and recycling metals from mixed metallic particles of crushed electronic wastes by vacuum metallurgy.

    Science.gov (United States)

    Zhan, Lu; Xu, Zhenming

    2009-09-15

    During the treatment of electronic wastes, a crushing process is usually used to strip metals from various base plates. Several methods have been applied to separate metals from nonmetals. However, mixed metallic particles obtained from these processes are still a mixture of various metals, including some toxic heavy metals such as lead and cadmium. With emphasis on recovering copper and other precious metals, there have hitherto been no satisfactory methods to recover these toxic metals. In this paper, the criterion of separating metals from mixed metallic particles by vacuum metallurgy is built. The results show that the metals with high vapor pressure have been almost recovered completely, leading to a considerable reduction of environmental pollution. In addition, the purity of copper in mixed particles has been improved from about 80 wt % to over 98 wt %.

  14. The Effectiveness of a NiCrY-Coating on a Powder Metallurgy Disk Superalloy

    Science.gov (United States)

    Gabb, Timothy P.; Miller, Robert A.; Nesbitt, James A.; Draper, Susan L.; Rogers, Richard B.; Telesman, Jack

    2018-01-01

    Protective ductile coatings could be necessary to mitigate oxidation and corrosion attack on superalloy disks in some turbine engine applications. However, the effects of coatings on fatigue life of the disk during service are an important concern. The objective of this study was to investigate how such a coating could perform after varied post-coating processing. Cylindrical gage fatigue specimens of powder metallurgy-processed disk superalloy LSHR were coated with a NiCrY coating, shot peened, preparation treated, exposed, and then subjected to fatigue at high temperature. The effects of varied shot peening, preparation treatment, and exposures on fatigue life with and without the coating were compared. Each of these variables and several of their interactions significantly influenced fatigue life.

  15. POSSIBLE USES OF PLASMA IN POWDER METALLURGY, WITH PARTICULAR REFERENCE TO SPHEROIDIZATION. Mozliwosci wykorzystania plazmy w zaganieniach metalurgii proszkow, ze szczegolnym uwzglednieniem procesu sferoidyzacji

    Energy Technology Data Exchange (ETDEWEB)

    Rutkowski, Wladyslaw; Szteke, Witold

    1971-09-15

    The present work contains a discussion of the problems of applying plasma in powder-metallurgical processes, application of powders to other processes with the use of plasma, and the application of other products of powder metallurgy in the plasma process. Results obtained with the spheroidization of AL{sub 2}O{sub 3}, Ta, and Ni powders are presented, as are the results of metallographic and microscopic investigations on these powders.

  16. Measurement of dynamic wedge angles and beam profiles by means of MRI ferrous sulphate gel dosimetry

    Science.gov (United States)

    Bengtsson, Magnus; Furre, Torbjørn; Rødal, Jan; Skretting, Arne; Olsen, Dag R.

    1996-02-01

    The purpose of this study is to examine the possible value of measuring the dose distribution in dynamic wedge photon beams using ferrous sulphate gel phantoms analysed by MRI. The wedge angles and dose profiles were measured for a field size of and for dynamic wedge angles of , , and using a 15 MV photon beam generated from a Clinac 2100 CD (Varian). The dose profiles obtained from MRI ferrous sulphate gel were in good agreement with the dose measurements performed with a diode detector array. Also, the wedge angles determined from the MRI ferrous sulphate gel agreed well with the values obtained by using film dosimetry and with calculations by use of TMS (treatment planning system) (Helax, Uppsala, Sweden). The study demonstrated that MRI ferrous sulphate gel dosimetry is an adequate tool for measurements of some beam characteristics of dynamic radiation fields.

  17. Hyperfine interactions and structures of ferrous hydroxide and green rust II in sulfated aqueous media

    International Nuclear Information System (INIS)

    Olowe, A.A.; Genin, J.M.R.; Bauer, P.

    1988-01-01

    A sulfated ferrous hydroxide is obtained by mixing NaOH with melanterite depending on the R = [SO 4 -- ]/[OH - ] ratio and leading by oxidation to the green rust II transient compound. Hyperfine parameters are presented. (orig.)

  18. Friction and wear of some ferrous-base metallic glasses

    Science.gov (United States)

    Miyoshi, K.; Buckley, D. H.

    1984-01-01

    Sliding friction experiments, X-ray photoelectron spectroscopy (XPS) analysis, and electron microscopy and diffraction studies were conducted with ferrous base metallic glasses (amorphous alloys) in contact with aluminium oxide at temperatures to 750 C in a vacuum. Sliding friction experiments were also conducted in argon and air atmospheres. The results of the investigation indicate that the coefficient of friction increases with increasing temperature to 350 C in vacuum. The increase in friction is due to an increase in adhesion resulting from surface segregation of boric oxide and/or silicon oxide to the surface of the foil. Above 500 C the coefficient of friction decreased rapidly. The decrease correlates with the segregation of boron nitride to the surface. Contaminants can come from the bulk of the material to the surface upon heating and impart boric oxide and/or silicon oxide at 350 C and boron nitride above 500 C. The segregation of contaminants is responsible for the friction behavior. The amorphous alloys have superior wear resistance to crystalline 304 stainless steel. The relative concentrations of the various constituents at the surfaces of the amorphous alloys are very different from the nominal bulk compositions.

  19. Modeling of mechanical properties for ferrous shape memory alloy

    International Nuclear Information System (INIS)

    Wada, Manabu; Ide, Yusuke; Mizote, Shinichiro; Naoi, Hisashi; Tsukimori, Kazuyuki

    2002-08-01

    In order to acquire technical data that are necessary for manufacture and design of the simulation test device for analyzing the core mechanics of Fast Breeder Reactor, ferrous shape memory alloy of Fe-28%Mn-6%Si-5%Cr is melted, forged and heat-treated. The microstructures are austenite. The specimens are deformed of up to 16% work-strain by tensile and compressive test, resulting in appearance of epsilon-martensite that is induced by stress. Then, heating at 673K for 10 minutes causes austenitic transformation from epsilon-martensite and shape memory strains are measured. We also investigate shape memory character of specimens, which are given, so called 'training treatment' of 5% pre-strain and recovery heat treatment. As a result, there is little difference between tensile and compressive test without training treatment and shape memory strain is 2% after being given 5% work-strain and recovery heat treatment. On the other hand, training treatment is remarkable and shape memory strain reaches to 3.7% after 5% work-strain. We analyze shape recovery character of this alloy specimen at three-point bending by using finite element method, and indicate possibility that its deformation behavior can be estimated from mechanical properties' data obtained at tensile and compressive test. (author)

  20. Assessment of Low Cycle Fatigue Behavior of Powder Metallurgy Alloy U720

    Science.gov (United States)

    Gabb, Tomothy P.; Bonacuse, Peter J.; Ghosn, Louis J.; Sweeney, Joseph W.; Chatterjee, Amit; Green, Kenneth A.

    2000-01-01

    The fatigue lives of modem powder metallurgy disk alloys are influenced by variabilities in alloy microstructure and mechanical properties. These properties can vary as functions of variables the different steps of materials/component processing: powder atomization, consolidation, extrusion, forging, heat treating, and machining. It is important to understand the relationship between the statistical variations in life and these variables, as well as the change in life distribution due to changes in fatigue loading conditions. The objective of this study was to investigate these relationships in a nickel-base disk superalloy, U720, produced using powder metallurgy processing. Multiple strain-controlled fatigue tests were performed at 538 C (1000 F) at limited sets of test conditions. Analyses were performed to: (1) assess variations of microstructure, mechanical properties, and LCF failure initiation sites as functions of disk processing and loading conditions; and (2) compare mean and minimum fatigue life predictions using different approaches for modeling the data from assorted test conditions. Significant variations in life were observed as functions of the disk processing variables evaluated. However, the lives of all specimens could still be combined and modeled together. The failure initiation sites for tests performed at a strain ratio R(sub epsilon) = epsilon(sub min)/epsilon(sub max) of 0 were different from those in tests at a strain ratio of -1. An approach could still be applied to account for the differences in mean and maximum stresses and strains. This allowed the data in tests of various conditions to be combined for more robust statistical estimates of mean and minimum lives.

  1. Ferrous Iron Oxidation by Thiobacillus ferrooxidans: Inhibition with Benzoic Acid, Sorbic Acid, and Sodium Lauryl Sulfate

    OpenAIRE

    Onysko, Steven J.; Kleinmann, Robert L. P.; Erickson, Patricia M.

    1984-01-01

    Benzoic acid, sorbic acid, and sodium lauryl sulfate at low concentrations (5 to 10 mg/liter) each effectively inhibited bacterial oxidation of ferrous iron in batch cultures of Thiobacillus ferrooxidans. The rate of chemical oxidation of ferrous iron in low-pH, sterile batch reactors was not substantially affected at the tested concentrations (5 to 50 mg/liter) of any of the compounds.

  2. Ferrous Iron Oxidation by Thiobacillus ferrooxidans: Inhibition with Benzoic Acid, Sorbic Acid, and Sodium Lauryl Sulfate

    Science.gov (United States)

    Onysko, Steven J.; Kleinmann, Robert L. P.; Erickson, Patricia M.

    1984-01-01

    Benzoic acid, sorbic acid, and sodium lauryl sulfate at low concentrations (5 to 10 mg/liter) each effectively inhibited bacterial oxidation of ferrous iron in batch cultures of Thiobacillus ferrooxidans. The rate of chemical oxidation of ferrous iron in low-pH, sterile batch reactors was not substantially affected at the tested concentrations (5 to 50 mg/liter) of any of the compounds. PMID:16346592

  3. Inhibitive Action of Ferrous Gluconate on Aluminum Alloy in Saline Environment

    Directory of Open Access Journals (Sweden)

    Patricia Abimbola Idowu Popoola

    2013-01-01

    Full Text Available The corrosion of aluminum in saline environment in the presence of ferrous gluconate was studied using weight loss and linear polarization methods. The corrosion rates were studied in different concentrations of ferrous gluconate 0.5, 1.0, 1.5, and 2.0 g/mL at 28°C. Experimental results revealed that ferrous gluconate in saline environment reduced the corrosion rate of aluminum alloy at the different concentrations studied. The minimum inhibition efficiency was obtained at 1.5 g/mL concentration of inhibitor while the optimum inhibition efficiency was achieved with 1.0 g/mL inhibitor concentration. The results showed that adsorption of ferrous gluconate on the aluminium alloy surface fits Langmuir adsorption isotherm. The potentiodynamic polarization results showed that ferrous gluconate is a mixed type inhibitor. Ferrous gluconate acted as an effective inhibitor for aluminium alloy within the temperature and concentration range studied. The data obtained from weight loss and potentiodynamic polarization methods were in good agreement.

  4. Ferrous-activated persulfate oxidation of arsenic(III) and diuron in aquatic system

    Energy Technology Data Exchange (ETDEWEB)

    Zhou, Lei [State Key Laboratory of Pollution Control and Resource Reuse, School of the Environment, Nanjing University, Nanjing 210023 (China); Zheng, Wei [Jiangsu Product Quality Supervision and Inspection Research Institute, Nanjing 210007 (China); Ji, Yuefei [State Key Laboratory of Pollution Control and Resource Reuse, School of the Environment, Nanjing University, Nanjing 210023 (China); Université Lyon 1, UMR CNRS 5256, Institut de recherches sur la catalyse et l’environnement de Lyon (IRCELYON), 2 Avenue Albert Einstein, F-69626 Villeurbanne (France); Zhang, Jinfeng; Zeng, Chao; Zhang, Ya; Wang, Qi [State Key Laboratory of Pollution Control and Resource Reuse, School of the Environment, Nanjing University, Nanjing 210023 (China); Yang, Xi, E-mail: yangxi@nju.edu.cn [State Key Laboratory of Pollution Control and Resource Reuse, School of the Environment, Nanjing University, Nanjing 210023 (China)

    2013-12-15

    Highlights: • Effective oxidation of As(III)/diuron is achieved by Fe(II)-activated persulfate. • Hydroxyl and sulfate radical play important roles in As(III) and diuron oxidation. • CA and Na{sub 2}S{sub 2}O{sub 3} are efficient and environmental friendly chelating agents. • DFT calculation is found to be useful for degradation products prediction. -- Abstract: In situ chemical oxidation (ISCO) can be an effective technology for the remediation of soil and groundwater polluted by organic and inorganic contaminants. This study investigated the oxidation of arsenic(III) (As(III)) and diuron using ferrous activated persulfate-based ISCO. The results indicated that Fe(II)/persulfate oxidation could be an effective method to oxidize As(III) and diuron. Effects of pH, S{sub 2}O{sub 8}{sup 2−} and Fe(II) amounts on the destruction of As(III) and diuron were examined in batch experiments. Acidic conditions favored the removal of As(III) and diuron. Four chelating agents, citric acid (CA), Na{sub 2}S{sub 2}O{sub 3}, diethylene triamine pentaacetic acid (DTPA) and ethylene diamine tetraacetic acid disodium (EDTA-Na{sub 2}) were used in attempt to maintain the quantity of ferrous ion in solution. In our experiments, CA and Na{sub 2}S{sub 2}O{sub 3} were found to be more effective than DTPA and EDTA-Na{sub 2}. Our results also revealed a widely practical prospect of inorganic chelating agent Na{sub 2}S{sub 2}O{sub 3}. Hydroxyl and sulfate radical were determined to play key roles in the oxidation process by using ethanol and tertiary butanol as molecular probes. Oxidation of As(III) yielded As(V) via the electron-transfer reaction. In the oxidation process of diuron, a stepwise nucleophilic substitution of chlorine by hydroxyl and a stepwise oxidation process of the methyl on the dimethylurea group by hydroxyl and sulfate radical were proposed.

  5. Laboratory Powder Metallurgy Makes Tough Aluminum Sheet

    Science.gov (United States)

    Royster, D. M.; Thomas, J. R.; Singleton, O. R.

    1993-01-01

    Aluminum alloy sheet exhibits high tensile and Kahn tear strengths. Rapid solidification of aluminum alloys in powder form and subsequent consolidation and fabrication processes used to tailor parts made of these alloys to satisfy such specific aerospace design requirements as high strength and toughness.

  6. Preliminary analysis about reducing production costs in uranium mining and metallurgy at Fuzhou uranium mine

    International Nuclear Information System (INIS)

    Wu Sanmao

    1999-01-01

    The production costs in uranium ming and metallurgy have been analyzed quantitatively term by term according to present production situation for The Uranium Mining and Metallurgy Corp, which is part of Fuzhou Uranium Mine. The principal factors influencing on the production costs and the main means reducing the production costs have been found

  7. Powder metallurgy in aerospace research: A survey

    Science.gov (United States)

    Blakeslee, H. W.

    1971-01-01

    The various techniques by which powders can be produced, as pure metals or as alloys, are discussed; the methods by which these powders can be formed into the final parts are explained as well as further processing that may be necessary to meet specific requirements. The NASA developments are detailed, and references are provided for those who wish to obtain further information characteristic of any methodology.

  8. Development of Cu-Be bronzes through powder metallurgy

    International Nuclear Information System (INIS)

    Abbas, M.

    2012-01-01

    Copper and copper alloys are the major group of commercial alloy. One of the important copper bronzes is Copper beryllium. This is unique among all engineering alloys. Copper beryllium alloy possesses the highest strength in all the copper base alloys. Development of copper beryllium alloy with powder metallurgy is challenging problem due to toxicity of beryllium dust. Purpose of this project to find out parameters by which copper beryllium with all unique properties should obtained. For this purpose efforts are put on development of alternative to copper beryllium system like copper-tin and copper-aluminum by powder metallurgy route. Different time of milling with uniaxial pressure of about 200 MPa and different sintering temperature according to phase diagram of alloy, with different soaking time is tried. Problems may occur like decrease in density after sintering, breaking of samples by Rockwell A, B and C indenters arid by hammering. Cold iso-static pressing at 300 MPa and sintering at above 900 degree C is used to develop copper beryllium alloy. As quenched samples are heat treated at 260 degree C, 315 degree C and 370 degree C with different soaking time of 30, 90 and 180 minutes to find out optimum time and temperature parameters. . It is observed that at aging at 260 degree C for 180 minutes, aging at 315 degree C for 180 minutes and aging at 370 degree C for 30 minutes produce optimum result. By observing these pellets by SEM, precipitates appeared in peak-aged alloy and bigger precipitates in over-aged alloy. Copper beryllium alloy developed through powder metallurgy has better prospects than other copper bronzes. (author)

  9. Annual report of the Metallurgy Division - period ending December 1975

    International Nuclear Information System (INIS)

    1976-01-01

    The R and D activities of the Metallurgy Division of the Bhabha Atomic Research Centre, Bombay (India) during 1975 are described. Some of the R and D programmes of particular interest to nuclear technology are: (1) flowsheet development for the production of rare metals and alloys of nuclear use e.g. hafnium, beryllium, zirconium (2) metallurgical, irradiation hardening and corrosion studies on Zr and Zr-base alloys and (3) studies of nuclear ceramic materials such as UO2 and beryllia. (M.G.B.)

  10. Properties of porous magnesium prepared by powder metallurgy.

    Science.gov (United States)

    Čapek, Jaroslav; Vojtěch, Dalibor

    2013-01-01

    Porous magnesium-based materials are biodegradable and promising for use in orthopaedic applications, but their applications are hampered by their difficult fabrication. This work reports the preparation of porous magnesium materials by a powder metallurgy technique using ammonium bicarbonate as spacer particles. The porosity of the materials depended on the amount of ammonium bicarbonate and was found to have strong negative effects on flexural strength and corrosion behaviour. However, the flexural strength of materials with porosities of up to 28 vol.% was higher than the flexural strength of non-metallic biomaterials and comparable with that of natural bone. Copyright © 2012 Elsevier B.V. All rights reserved.

  11. Fabrication and characterization of Am, Np and Cm bearing MOX fuel obtained by conventional powder metallurgy

    Energy Technology Data Exchange (ETDEWEB)

    Jankowiak, A.; Leorier, C.; Desmouliere, F.; Donnet, L. [Commissariat a l' Energie Atomique (CEA), CEA/DEN/VRH/DTEC/SDTC/LEMA, 30207 Bagnols-sur-Ceze cedex (France)

    2008-07-01

    Transmutation of minor actinides enables to produce energy and to turn them into shorter-lived nuclides. This promising way to reduce the long-term waste radiotoxicity is world wide investigated. In the framework of the Global Actinide Cycle International Demonstration and regarding the homogeneous recycling for transmutation in fast reactors, minor actinides (Am, Np, Cm) bearing MOX fuel pellets were fabricated in the ATALANTE facility by a conventional powder metallurgy process (milling then pressing and finally sintering). The sintered pellets were submitted to a visual inspection where neither crack nor strain was detected. In addition, the pellets exhibit a density in the range 93-96% TD which makes them proper to the irradiation in fast reactors. The pellets were characterized by XRD (X radiation diffraction) and SEM (scanning electron microscopy) combined to image analysis. (authors)

  12. Physical and mechanical metallurgy of high purity Nb for accelerator cavities

    International Nuclear Information System (INIS)

    Bieler, T.R.; Wright, N.T.; Pourboghrat, F.; Compton, C.; Hartwig, K.T.; Baars, D.; Zamiri, A.; Chandrasekaran, S.; Darbandi, P.; Jiang, H.; Skoug, E.; Balachandran, S.; Ice, G.E.; Liu, W.

    2010-01-01

    In the past decade, high Q values have been achieved in high purity Nb superconducting radio frequency (SRF) cavities. Fundamental understanding of the physical metallurgy of Nb that enables these achievements is beginning to reveal what challenges remain to establish reproducible and cost-effective production of high performance SRF cavities. Recent studies of dislocation substructure development and effects of recrystallization arising from welding and heat treatments and their correlations with cavity performance are considered. With better fundamental understanding of the effects of dislocation substructure evolution and recrystallization on electron and phonon conduction, as well as the interior and surface states, it will be possible to design optimal processing paths for cost-effective performance using approaches such as hydroforming, which minimizes or eliminates welds in a cavity.

  13. Annual report of the Metallurgy Division [for the] period ending December 1976

    International Nuclear Information System (INIS)

    Elayaperumal, K.; Gupta, C.K.; Mukhopadhyay, P.; Rao, S.V.K.

    1977-01-01

    An account of the work done in the Metallurgy Division of the Bhabha Atomic Research Centre, Bombay, during the calendar year 1976 is given. Some of the major achievements are: (1) production of boron carbide and boral sheet for the Trombay R-5 reactor under construction, (2) production of niobium metal for the manufacture of Zr-Nb-Cu alloy garter springs, (3) development of a process for graphite coating on zircaloy, (4) studies on structural and metal physics aspects of zirconium alloys and steels, (5) studies on the corrosion behaviour of zircaloy-2 as affected by the replacement of helium and stress corrosion cracking of zircaloy fuel tubes in iodine atmosphere and (6) production of high density UO 2 pellets with stable microstructures and sinterable magnesium oxide for MHD application. (M.G.B.)

  14. Beta Ti-45Nb and Ti-50Nb alloys produced by powder metallurgy for aerospace application

    Energy Technology Data Exchange (ETDEWEB)

    Martins, G.V.; Trava-Airoldi, V.J.; Machado, J.P.B., E-mail: givmartins@yahoo.com.br, E-mail: vladimir@las.inpe.br, E-mail: joaopaulo@las.inpe.br [Instituto Nacional de Pesquisas Espaciais (INPE), Sao Jose dos Campos, SP (Brazil); Silva, C.R.M., E-mail: cosmeroberto@gmail.com [Universidade de Brasilia (UnB), Brasilia, DF (Brazil); Nunes, C.A., E-mail: cnunes@demar.eel.usp.br [Universidade de Sao Paulo (EEL/USP), Lorena, SP (Brazil). Polo Urbo Industrial; Borges Junior, L.A., E-mail: borges.jr@itelefonica.com.br [Centro Universitario de Volta Redond (UNIFOA), Volta Redonda, RJ (Brazil)

    2009-07-01

    Beta titanium alloys parts are used on advanced aerospace systems because of their high strength to weight ratio and excellent corrosion resistance. Production of powder metallurgy titanium alloys components may lead to a substantial reduction in the cost, compared to those produced by conventional cast and wrought processes, because additional working operations and material waste can be avoided. In this work, beta Ti-45Nb and Ti- 50Nb were produced by the blended elemental technique, followed by uniaxial and cold isostatic pressing with subsequent densification by sintering. Sintered samples were characterized for phase composition by XRD, microstructure by SEM, hardness by Vickers indentation, specific mass by the Archimedes method and elastic modulus by resonance ultrasound. The sintered samples presented only the beta phase, higher hardness and lower elastic modulus when compared to Ti6Al4V alloy and experimental specific mass value near theoretical specific mass. These characteristics are adequate for application on several aerospace parts. (author)

  15. 9th Mining and metallurgy international congress, Leon, 24-28 May 1994

    International Nuclear Information System (INIS)

    1994-01-01

    The 9th Mining and Metallurgy International Congress had 201 communications. These was articulated into 4th areas: 1.- Geological resources management and profit: 1.1- Geological and mining research on geologic resources. 1.2.- Non energetic mineral resources exploitation. 1.3- Hydro-geologic and geothermia resources. 1.4- Geologic resources and planning. 2.- Energy: 2.1.- Energetic mining.- 2.2 Oil and gas. 2.3.- Electricity production and distribution. 2.4.- Coal clean technologies. 2.5.- Energetic management. 3.- Material engineering: 3.1.- Minerallurgia and metallurgic processes. 3.2- Industrial minerals and ornamental 10cks. 3.3 .- Building materials. 3.4 Advanced technology materials. 4.- Environmental and territorial engineering in basic industry. 4.1.-Valuation of environmental impacts. 4.2.- Restoration engineering in mining. 4.3.- Effluent and residue engineering. 4.4.- Environmental management and clean technologies 4.5.- Natural and technological risks

  16. Beta Ti-45Nb and Ti-50Nb alloys produced by powder metallurgy for aerospace application

    International Nuclear Information System (INIS)

    Martins, G.V.; Trava-Airoldi, V.J.; Machado, J.P.B.; Silva, C.R.M.; Nunes, C.A.

    2009-01-01

    Beta titanium alloys parts are used on advanced aerospace systems because of their high strength to weight ratio and excellent corrosion resistance. Production of powder metallurgy titanium alloys components may lead to a substantial reduction in the cost, compared to those produced by conventional cast and wrought processes, because additional working operations and material waste can be avoided. In this work, beta Ti-45Nb and Ti- 50Nb were produced by the blended elemental technique, followed by uniaxial and cold isostatic pressing with subsequent densification by sintering. Sintered samples were characterized for phase composition by XRD, microstructure by SEM, hardness by Vickers indentation, specific mass by the Archimedes method and elastic modulus by resonance ultrasound. The sintered samples presented only the beta phase, higher hardness and lower elastic modulus when compared to Ti6Al4V alloy and experimental specific mass value near theoretical specific mass. These characteristics are adequate for application on several aerospace parts. (author)

  17. Accelerated Threshold Fatigue Crack Growth Effect-Powder Metallurgy Aluminum Alloy

    Science.gov (United States)

    Piascik, R. S.; Newman, J. A.

    2002-01-01

    Fatigue crack growth (FCG) research conducted in the near threshold regime has identified a room temperature creep crack growth damage mechanism for a fine grain powder metallurgy (PM) aluminum alloy (8009). At very low (Delta) K, an abrupt acceleration in room temperature FCG rate occurs at high stress ratio (R = K(sub min)/K(sub max)). The near threshold accelerated FCG rates are exacerbated by increased levels of K(sub max) (K(sub max) = 0.4 K(sub IC)). Detailed fractographic analysis correlates accelerated FCG with the formation of crack-tip process zone micro-void damage. Experimental results show that the near threshold and K(sub max) influenced accelerated crack growth is time and temperature dependent.

  18. Development of fully dense and high performance powder metallurgy HSLA steel using HIP method

    Science.gov (United States)

    Liu, Wensheng; Pang, Xinkuan; Ma, Yunzhu; Cai, Qingshan; Zhu, Wentan; Liang, Chaoping

    2018-05-01

    In order to solve the problem that the mechanical properties of powder metallurgy (P/M) steels are much lower than those of traditional cast steels with the same composition due to their porosity, a high–strength–low–alloy (HSLA) steel with fully dense and excellent mechanical properties was fabricated through hot isostatic pressing (HIP) using gas–atomized powders. The granular structure in the P/M HIPed steel composed of bainitic ferrite and martensite–austenite (M–A) islands is obtained without the need of any rapid cooling. The P/M HIPed steel exhibit a combination of tensile strength and ductility that surpasses that of conventional cast steel and P/M sintered steel, confirming the feasibility of fabricating high performance P/M steel through appropriate microstructural control and manufacture process.

  19. Physical and mechanical metallurgy of high purity Nb for accelerator cavities

    Directory of Open Access Journals (Sweden)

    T. R. Bieler

    2010-03-01

    Full Text Available In the past decade, high Q values have been achieved in high purity Nb superconducting radio frequency (SRF cavities. Fundamental understanding of the physical metallurgy of Nb that enables these achievements is beginning to reveal what challenges remain to establish reproducible and cost-effective production of high performance SRF cavities. Recent studies of dislocation substructure development and effects of recrystallization arising from welding and heat treatments and their correlations with cavity performance are considered. With better fundamental understanding of the effects of dislocation substructure evolution and recrystallization on electron and phonon conduction, as well as the interior and surface states, it will be possible to design optimal processing paths for cost-effective performance using approaches such as hydroforming, which minimizes or eliminates welds in a cavity.

  20. Structure and properties of powder metallurgy constructional steel of different densities

    International Nuclear Information System (INIS)

    Gulyaev, A.P.; Moskvina, T.P.

    1986-01-01

    A specific feature of powder metallurgy steels is porosity, the degree of which depends upon the method of their production. This article establishes the influence of a small amount of porosity on the mechanical properties of powder metallurgy constructional steel. The structure of heat-treated cast and powder metallurgy steels with different porosities are shown. The results of mechanical tests of the experimental steels with different porosities are shown. With an increase in porosity the nonmetallic inclusion rating of the powder metallurgy constructional steel increases, primarily as the result of the increase in the coarse particles, which is caused by the lower degree of plastic deformation in pressing. With an increase in porosity the mechanical properties of the powder metallurgy steel become poorer: the hardness and strength properties with a porosity of more than 3-5%, the plasticity with more than 1-2%, and the toughness even with a porosity of 1%

  1. Ferrous ammonium phosphate (FeNH₄PO₄) as a new food fortificant: iron bioavailability compared to ferrous sulfate and ferric pyrophosphate from an instant milk drink.

    Science.gov (United States)

    Walczyk, Thomas; Kastenmayer, Peter; Storcksdieck Genannt Bonsmann, Stefan; Zeder, Christophe; Grathwohl, Dominik; Hurrell, Richard F

    2013-06-01

    The main purpose of this study was to establish bioavailability data in humans for the new (Fe) fortification compound ferrous ammonium phosphate (FAP), which was specially developed for fortification of difficult-to-fortify foods where soluble Fe compounds cannot be used due to their negative impact on product stability. A double-blind, randomized clinical trial with cross-over design was conducted to obtain bioavailability data for FAP in humans. In this trial, Fe absorption from FAP-fortified full-cream milk powder was compared to that from ferric pyrophosphate (FPP) and ferrous sulfate. Fe absorption was determined in 38 young women using the erythrocyte incorporation dual stable isotope technique (⁵⁷Fe, ⁵⁸Fe). Geometric mean Fe absorption from ferrous sulfate, FAP and FPP was 10.4, 7.4 and 3.3 %, respectively. Fe from FAP was significantly better absorbed from milk than Fe from FPP (p soluble reference compound (p = 0.0002). Absorption ratios of FAP and FPP relative to ferrous sulfate as a measure of relative bioavailability were 0.71 and 0.32, respectively. The results of the present studies show that replacing FPP with FAP in full-cream milk could significantly improve iron bioavailability.

  2. A spectroscopic and surface microhardness study of enamel exposed to beverages supplemented with ferrous fumarate and ferrous sulfate. A randomized in vitro trial.

    Science.gov (United States)

    Xavier, Arun M; Rai, Kavita; Hegde, Amitha M; Shetty, Suchetha

    2016-06-01

    To compare the efficacy between supplementing ferrous fumarate and ferrous sulfate to carbonated beverages by recording the in vitro mineral loss and surface microhardness (SMH) changes in human enamel. 120 enamel blocks each (from primary and permanent teeth) were uniformly prepared and the initial SMH was recorded. These enamel specimens were equally divided (n = 60) for their respective beverage treatment in Group 1 (2 mmol/L ferrous sulfate) and Group 2 (2 mmol/L ferrous fumarate). Each group was further divided into three subgroups as Coca-Cola, Sprite and mineral water (n= 10). The specimens were subjected to three repetitive cycles of respective treatment for a 5-minute incubation period, equally interspaced by 5-minute storage in artificial saliva. The calcium and phosphate released after each cycle were analyzed spectrophotometrically and the final SMH recorded. The results were tested using student's t-test, one-way ANOVA and Wilcoxon signed rank test (P Coca-Cola (P < 0.005).

  3. Production of ferrous sulfate from residue from the iron mining; Producao de sulfato ferroso a partir de residuo proveniente da mineracao de ferro

    Energy Technology Data Exchange (ETDEWEB)

    Cardoso, K.A; Riella, H.G.; Abreu, E.F. [Universidade Federal de Santa Catarina (UFSC), Florianopolis, SC (Brazil). Dept. de Engrenharia Quimica; Carvalho, E.F. Urano de; Durazzo, M. [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil). Centro de Combustivel Nuclear

    2012-11-15

    This paper was developed from a residue obtained by processing iron ore exploited by the mining company Samarco S/A. The residue was characterized and the analyses showed that it contains about 70% of the mineral hematite (Fe{sub 2}O{sub 3}) and also that some economically important products could be produced. One is the ferrous sulfate that can be used in pharmaceuticals and also that can be used in the treatment of iron deficiency anemia. The iron, in addition to is importance for the industrial production of steel and parts in general, also has great biological importance in all living beings. In order to produce ferrous sulfate from the byproduct in question, it was developed a obtaining route using metallic iron as hematite reductor and sulfuric acid to form the salt. (author)

  4. Development of a New Ferrous Aluminosilicate Refractory Material for Investment Casting of Aluminum Alloys

    Science.gov (United States)

    Yuan, Chen; Jones, Sam; Blackburn, Stuart

    2012-12-01

    Investment casting is a time-consuming, labour intensive process, which produces complex, high value-added components for a variety of specialised industries. Current environmental and economic pressures have resulted in a need for the industry to improve current casting quality, reduce manufacturing costs and explore new markets for the process. Alumino-silicate based refractories are commonly used as both filler and stucco materials for ceramic shell production. A new ceramic material, norite, is now being produced based on ferrous aluminosilicate chemistry, having many potential advantages when used for the production of shell molds for casting aluminum alloy. This paper details the results of a direct comparison made between the properties of a ceramic shell system produced with norite refractories and a typical standard refractory shell system commonly used in casting industry. A range of mechanical and physical properties of the systems was measured, and a full-scale industrial casting trial was also carried out. The unique properties of the norite shell system make it a promising alternative for casting aluminum based alloys in the investment foundry.

  5. Powder metallurgy at Savannah River Laboratory

    International Nuclear Information System (INIS)

    Peacock, H.B.

    1978-12-01

    Development of a powder metallurgical process for the manufacture of reactor grade fuel tubes is being carried out at the Savannah River Laboratory (SRL). Using the P/M technology, cores were isostatically compacted with 100 wt % U 3 O 8 and coextruded tubes fabricated which contain up to approx. 80% cores clad with aluminum. Irradiation tests were completed for tubes with up to 59 wt % oxide. Post-irradiation inspection showed no significant swelling for 40% burnup. Thermal testing of sections from irradiated tubes showed that the threshold temperature for blister formation increased as the fission density of oxide decreased. Procedures are discussed for making PM cores and extruded tubes at SRL. Both laboratory and full-scale tests are presented

  6. An application of powder metallurgy to dentistry.

    Science.gov (United States)

    Oda, Y; Ueno, S; Kudoh, Y

    1995-11-01

    Generally, the dental casting method is used to fabricate dental prostheses made with metal. The method of fabricating dental prostheses from sintered titanium alloy has certain advantages: the elimination of casting defects, a sintering temperature that is lower than the melting point, and a shorter processing time. By examining (1) the properties of green, sintered compacts of titanium powder, (2) the effects of adding aluminum powder on the properties of green, sintered compacts of Ti-Al compound, and (3) the effects of adding copper powder on the properties of green, sintered compacts of Ti-Al-Cu compound, the authors developed a sintered titanium alloy on a trial basis. Because the properties satisfied the requirements of dental restorations, a powder metallurgical method of making dental restorations from this sintered titanium alloy was devised. Applications of such sintered titanium alloys for the metal coping of metal-ceramic crowns and denture base plates were discussed.

  7. Use of ferrous industrial wastes as binding materials for construction; Empleo de residuos industriales siderurgicos como materiales aglomerantes en construccion

    Energy Technology Data Exchange (ETDEWEB)

    Mymrin, V.A. [Centro Nacional de Investigaciones Metalurgicas. CENIM. Madrid (Spain)

    1998-12-01

    Several ferrous and non ferrous metallurgical wastes, slag, powdered wastes, alkaline liquors, etc., can be used as binding materials to produce new building materials. These materials can be used in place of concretes made of cement, crushed stones, sand and gravel mixtures in several applications, road, industrial and airport foundations, etc. They are leaching resistant, so heavy metals do not migrate to the environment. These new materials, with a new structure, are obtained by mixing in right proportion of two or three industrial wastes or with mixtures of two of them and natural soils without any addition of traditional binders like and without heating. The main advantages are the solution of the problem of disposal of industrial wastes and the lower cost of the new materials, 5 to 6 times cheaper than traditional. Several examples of roads existing in Russia, even in Siberia and other northern regions, demonstrate the benefit of this process because after 20 years they still offer a good performance. (Author) 8 refs.

  8. Metallurgy of platinoids. Studies of industrial cases

    International Nuclear Information System (INIS)

    Blazy, P.; Jdid, E. A.

    2004-01-01

    The platinoids deposits, currently in exploitation, are often associated with dunitic and gabbroitic ultra-basic rocks containing copper, nickel and iron sulfides. The proportion of platinoids in these deposits is variable and requires generally an adaptation of the industrial processes for their recovery. Nevertheless, we can consider that the classical industrial way consists to treat the composite concentrates of copper-nickel-platinoids sulfides by melting/conversion operations following by hydrometallurgical operations of recovery of the basic metals Cu, Ni. These last ones concentrate the platinoids in leaching residues. In these residues, the platinoids are extracted and separated by hydrometallurgical ways including different techniques: dissolution, selective precipitation, distillation, solvent extraction, resins...The great variety of uses of platinoids makes their recycling difficult. The wastes are often too complex for being economically recycling. The environmental protection depends of the type of industry (metallurgical, chemical, mining). Some products present risks of fire and explosion. The toxicity often appears by superficial allergies and by serious troubles in case of ingestion of soluble salts. (O.M.)

  9. The mysterious world of plutonium metallurgy: Past and future

    International Nuclear Information System (INIS)

    Hecker, S.S.; Hammel, E.F.

    1998-01-01

    The first atomic bomb detonated at the Trinity Site in New Mexico on July 16, 1945, used plutonium, a man-made element discovered < 5 yr earlier. The story of how Manhattan Project scientists and engineers tackled the mysteries of this element and fabricated it into the first atomic bomb is one of the most fascinating in the history of metallurgy and materials. The authors are currently trying to generate renewed interest in plutonium metallurgy because of the challenge posed by President Clinton, i.e., to keep the nuclear stockpile of weapons safe and reliable without nuclear testing. The stockpile stewardship challenge requires either a lifetime extension of the plutonium components or a remanufacture--neither of which can be verified by testing. In turn, this requires that one achieve a better fundamental understanding of plutonium. Of special interest is the effect of self-irradiation on the properties and on the long-term stability of plutonium and its alloys. Additional challenges arise from long-term concerns about disposing of plutonium and dealing with its environmental legacy. It is imperative to interest the next generation of students in these plutonium challenges

  10. Stress Analysis of Non-Ferrous Metals Welds by Numerical Simulation

    Directory of Open Access Journals (Sweden)

    Kravarikova Helena

    2017-01-01

    Full Text Available Thermal energy welded material unevenly heated and thus supports the creation of tension. During the fusing process welding transient tensions generated in the welded material. Generation of the transient tensions depends on the thermal expansion and fixed permanently welded parts. Tensions are the result of the interaction of material particles. For welded parts and constructions it is necessary to know the size and direction of application of tensions. The emerging tensions can cause local change or a total deformation of welded materials. Deformations and residual stresses impair the performance of a welded construction, reduces the stability of the parts. To reduce or eliminate of action or a screening direction stresses and strains it is necessary to know the mechanism of their emergence. It is now possible to examine the emergence of tensions numerical experiments on any model using numerical simulation using FEM. Results of numerical experiment is the analysis of stress and deformation course. In the plane the tension it divided into normal σ and τ tangential folders. Decomposition stress on components simplifies the stress analysis. The results obtained from numerical analysis are correct to predict the stress distribution and size. The paper presents the results of numerical experiments stress analysis solutions fillet welds using FEM numerical simulation of welding of non-ferrous metals.

  11. Improvement of the Wear Resistance of Ferrous Alloys by Electroless Plating of Nickel

    Science.gov (United States)

    Kaleicheva, J. K.; Karaguiozova, Z.

    2018-01-01

    The electroless nickel (Ni) and composite nickel - nanodiamond (Ni+DND) coatings are investigated in this study. The method EFTTOM-NICKEL for electroless nickel plating with nanosized strengthening particles (DND 4-6 nm) is applied for the coating deposition. The coatings are deposited on ferrous alloys samples. The wear resistance of the coatings is performed by friction wear tests under 50-400 MPa loading conditions - in accordance with a Polish Standard PN-83/H-04302. The microstructure observations are made by optic metallographic microscope GX41 OLIMPUS and the microhardness is determined by Vickers Method. Tests for wear resistance, thickness and microhardness measurements of the coatings without heat treatment and heat treatment are performed. The heat treatment regime is investigated with the aim to optimize the thermal process control of the coated samples without excessive tempering of the substrate material. The surface fatigue failure is determined by contact fatigue test with the purpose to establish suitable conditions for production of high performance materials.

  12. Potential for microbial oxidation of ferrous iron in basaltic glass.

    Science.gov (United States)

    Xiong, Mai Yia; Shelobolina, Evgenya S; Roden, Eric E

    2015-05-01

    Basaltic glass (BG) is an amorphous ferrous iron [Fe(II)]-containing material present in basaltic rocks, which are abundant on rocky planets such as Earth and Mars. Previous research has suggested that Fe(II) in BG can serve as an energy source for chemolithotrophic microbial metabolism, which has important ramifications for potential past and present microbial life on Mars. However, to date there has been no direct demonstration of microbially catalyzed oxidation of Fe(II) in BG. In this study, three different culture systems were used to investigate the potential for microbial oxidation of Fe(II) in BG, including (1) the chemolithoautotrophic Fe(II)-oxidizing, nitrate-reducing "Straub culture"; (2) the mixotrophic Fe(II)-oxidizing, nitrate-reducing organism Desulfitobacterium frappieri strain G2; and (3) indigenous microorganisms from a streambed Fe seep in Wisconsin. The BG employed consisted of clay and silt-sized particles of freshly quenched lava from the TEB flow in Kilauea, Hawaii. Soluble Fe(II) or chemically reduced NAu-2 smectite (RS) were employed as positive controls to verify Fe(II) oxidation activity in the culture systems. All three systems demonstrated oxidation of soluble Fe(II) and/or structural Fe(II) in RS, whereas no oxidation of Fe(II) in BG material was observed. The inability of the Straub culture to oxidize Fe(II) in BG was particularly surprising, as this culture can oxidize other insoluble Fe(II)-bearing minerals such as biotite, magnetite, and siderite. Although the reason for the resistance of the BG toward enzymatic oxidation remains unknown, it seems possible that the absence of distinct crystal faces or edge sites in the amorphous glass renders the material resistant to such attack. These findings have implications with regard to the idea that Fe(II)-Si-rich phases in basalt rocks could provide a basis for chemolithotrophic microbial life on Mars, specifically in neutral-pH environments where acid-promoted mineral dissolution and

  13. Evaluation of Ferric and Ferrous Iron Therapies in Women with Iron Deficiency Anaemia

    Science.gov (United States)

    Berber, Ilhami; Erkurt, Mehmet Ali; Aydogdu, Ismet; Kuku, Irfan

    2014-01-01

    Introduction. Different ferric and ferrous iron preparations can be used as oral iron supplements. Our aim was to compare the effects of oral ferric and ferrous iron therapies in women with iron deficiency anaemia. Methods. The present study included 104 women diagnosed with iron deficiency anaemia after evaluation. In the evaluations performed to detect the aetiology underlying the iron deficiency anaemia, it was found and treated. After the detection of the iron deficiency anaemia aetiology and treatment of the underlying aetiology, the ferric group consisted of 30 patients treated with oral ferric protein succinylate tablets (2 × 40 mg elemental iron/day), and the second group consisted of 34 patients treated with oral ferrous glycine sulphate tablets (2 × 40 mg elemental iron/day) for three months. In all patients, the following laboratory evaluations were performed before beginning treatment and after treatment. Results. The mean haemoglobin and haematocrit increases were 0.95 g/dL and 2.62% in the ferric group, while they were 2.25 g/dL and 5.91% in the ferrous group, respectively. A significant difference was found between the groups regarding the increase in haemoglobin and haematocrit values (P < 0.05). Conclusion. Data are submitted on the good tolerability, higher efficacy, and lower cost of the ferrous preparation used in our study. PMID:25006339

  14. Effects of ferrous ions on the reductive dechlorination of trichloroethylene by zero-valent iron

    International Nuclear Information System (INIS)

    Liu, C.-C.; Tseng, D.-H.; Wang, C.-Y.

    2006-01-01

    The surface characteristics of zero-valent iron (ZVI) and the efficiency of reductive dechlorination of trichloroethylene (TCE) in the presence of ferrous ions were studied. The experimental results indicated that the acid-washing of a metallic iron sample enhanced the efficiency of TCE degradation by ZVI. This occurred because acid-washing changed the conformation of oxides on the surface of iron from maghemite (γ-Fe 2 O 3 ) to the more hydrated goethite (α-FeOOH), as was confirmed by XPS analysis. However, when ferrous ions were simultaneous with TCE in water, the TCE degradation rate decreased as the concentration of ferrous ion increased. This was due to the formation of passive precipitates of ferrous hydroxide, including maghemite and magnetite (Fe 3 O 4 ), that coated on the surface of acid-washed ZVI, which as a result inhibited the electron transfer and catalytic hydrogenation mechanisms. On the other hand, in an Fe 0 -TCE system without the acid-washing pretreatment of ZVI, ferrous ions were adsorbed into the maghemite lattice which was then converted to semiconductive magnetite. Thus, the electrons were transferred from the iron surface and passed through the precipitates, allowing for the reductive dechlorination of TCE

  15. Effects of ferrous ions on the reductive dechlorination of trichloroethylene by zero-valent iron

    Energy Technology Data Exchange (ETDEWEB)

    Liu, C.-C. [Graduate Institute of Environmental Engineering, National Central University, Chungli, Taiwan 32001 (China); Tseng, D.-H. [Graduate Institute of Environmental Engineering, National Central University, Chungli, Taiwan 32001 (China)]. E-mail: dhtseng@ncuen.ncu.edu.tw; Wang, C.-Y. [Graduate Institute of Environmental Engineering, National Central University, Chungli, Taiwan 32001 (China)

    2006-08-25

    The surface characteristics of zero-valent iron (ZVI) and the efficiency of reductive dechlorination of trichloroethylene (TCE) in the presence of ferrous ions were studied. The experimental results indicated that the acid-washing of a metallic iron sample enhanced the efficiency of TCE degradation by ZVI. This occurred because acid-washing changed the conformation of oxides on the surface of iron from maghemite ({gamma}-Fe{sub 2}O{sub 3}) to the more hydrated goethite ({alpha}-FeOOH), as was confirmed by XPS analysis. However, when ferrous ions were simultaneous with TCE in water, the TCE degradation rate decreased as the concentration of ferrous ion increased. This was due to the formation of passive precipitates of ferrous hydroxide, including maghemite and magnetite (Fe{sub 3}O{sub 4}), that coated on the surface of acid-washed ZVI, which as a result inhibited the electron transfer and catalytic hydrogenation mechanisms. On the other hand, in an Fe{sup 0}-TCE system without the acid-washing pretreatment of ZVI, ferrous ions were adsorbed into the maghemite lattice which was then converted to semiconductive magnetite. Thus, the electrons were transferred from the iron surface and passed through the precipitates, allowing for the reductive dechlorination of TCE.

  16. Development and characterization of Al-Zn alloy by ingot metallurgy and powder metallurgy with improved mechanical properties

    International Nuclear Information System (INIS)

    Waseem, M.; Awais, H.B.; Zauha, M.S.; Tariq, N.H.

    2007-01-01

    Current project focuses on the production of AI-Zn alloy AA7075 used for wide range of applications like Aircraft components, missile and other structural applications. The above alloy was developed by two different routes. One was melting /casting, after which alloy was characterized by microstructural - examination (optical and SEM) and mechanical testing. Other route was the preparation of this alloy by powder metallurgy. This involves preparation of powders, mechanical alloying, compaction, sintering, rolling, solution treatment and aging then analysis. Powders of Aluminum, Zinc and powders of master alloys of AI-Cu, AI-Mg, AI-Mn, and AI-Cr were Mechanical alloyed. Then this powder was compacted by uniaxial press to form pellets. Sintering was carried out at 500 degree C and then hot rolled in Ar atmosphere. After solution and aging treatments samples were characterized. It is observed that there is about 12-21% improvement in mechanical properties such as tensile strength, yield strength, ductility and fracture toughness due to the more fine microstructure and less segregation than ingot metallurgy route. (author)

  17. Effect of process variables on the flexural behavior of alloys Ti - 3% at. X (X = Nb, Ta) obtained by powder metallurgy; Efecto de las variables de proceso sobre el comportamiento a flexion de aleaciones Ti - 3% at. X (X = Nb, Ta) obtenidas por pulvimetalurgia

    Energy Technology Data Exchange (ETDEWEB)

    Franconetti, P.; Candel, J. J.; Vicente, A.; Amigo, V.

    2013-07-01

    Niobium and tantalum are added to titanium alloys to form new beta alloys with higher biocompatibility for biomedical applications. Both elements have a high melting point, that is the reason for their limited solid state diffusion. In this work samples of titanium with 3% at. niobium and tantalum have been manufactured by powder metallurgy. The effect of the compacting pressure, temperature and the sintering time on the strength, elasticity and ductility in bending has been studied. The results show that both elements behave similarly: flexural strength increases between 20-25%, elasticity between 0-10% and ductility over 150%. Therefore, the addition of these elements is beneficial to mechanical properties. Statistical analysis shows that the effect of temperature and pressure are important, while the effect of time is insignificant and even harmful in these alloys. (Author)

  18. Investigation of hydrostatic extrusion and other deformation modes for the fabrication of multifilamentary niobium--tin superconductors by a powder metallurgy approach

    International Nuclear Information System (INIS)

    MacLeod, G.E.

    1977-06-01

    Various aspects of a powder metallurgy approach to fabricate filamentary niobium-tin superconducting wire were investigated. Difficulties occurred due to lack of complete tin infiltration of the sintered niobium rod, formation of intermetallics during infiltration, and both cladding and core fracture during mechanical reduction. The influence of sintering time, infiltration temperature, and deformation mode was investigated. Progress is reported on the clarification of the role of several of the important process parameters

  19. Research of radiation protection standard system in uranium mining and metallurgy

    International Nuclear Information System (INIS)

    Lian Guoxi; Song Liquan; Xie Zhanjun

    2011-01-01

    The contents of radiation and environment protection standards used in uranium mining and metallurgy are analyzed and the existent problems in current standard system are pointed out. A new standard system is established according to theory of systematology and the actuality of uranium mining and metallurgy. Some standard checklists which need to be complemented, corrected, deleted and used during the work of perfection and complementation of standard system are presented. The procedures of establishing new standard system are described, and some suggestions on the establishment and implementation of radiation protection standard system in uranium mining and metallurgy are put forward. (authors)

  20. CORRELATION BETWEEN PUBLIC FUNDING AND NON-FERROUS INDUSTRY. EVIDENCE FROM CEE AND ROMANIA

    Directory of Open Access Journals (Sweden)

    Brîndusa COVACI

    2016-12-01

    Full Text Available The paper aims at presenting important approaches of the influence of the public funding to industry, especially non-ferrous, in the Countries from Eastern Europe (CEE and Romania. Studies presented in the paper show that the industry funding had been sustained by the European Commission in the community area, but particularly in CEE area. The impact of industry funding will never be exactly measured, but important data can be presented in order to foresee the future development of the European industry. Specific for non-ferrous industry, in the article there are presented important items, as turnover, value added cost, exports, production, which are correlated to EU funds absorption in order to measure the efficiency of the public funding for 2007-2013 period (national and EU funds and the welfare of the CEE and Romanian non-ferrous sector.

  1. An application of powder metallurgy for the LHC

    CERN Document Server

    Sgobba, Stefano

    2004-01-01

    The cold mass of the 1232 superconducting dipole magnets of LHC, operating at 1.9 K, is enclosed by a shrinking cylinder and two end covers at its extremities. The covers are structural components that must retain high strength and toughness at cryogenic temperature. They are manufactured by Metso Oy /FI in AISI 316 LN steel by Powder Metallurgy (PM) and Hot Isostatic Pressing. PM represents an attractive near net shaping technique for these components of complex geometry for which dimension tolerances, dimensional stability, weldability are key issues for magnet fabrication, and mechanical properties, ductility and leak tightness have to be guaranteed during operation. The material of the covers and its welds have been fully characterized and mechanically tested down to 4.2 K at CERN. The fine grained structure, the absence of residual stresses, the full isotropy of mechanical properties associated to the low level of Prior Particle Boundaries oxides result in superior mechanical properties and high ductilit...

  2. Phase Stability of a Powder Metallurgy Disk Superalloy

    Science.gov (United States)

    Gabb, Timothy P.; Gayda, John; Kantzos, P.; Telesman, Jack; Gang, Anita

    2006-01-01

    Advanced powder metallurgy superalloy disks in aerospace turbine engines now entering service can be exposed to temperatures approaching 700 C, higher than those previously encountered. They also have higher levels of refractory elements, which can increase mechanical properties at these temperatures but can also encourage phase instabilities during service. Microstructural changes including precipitation of topological close pack phase precipitation and coarsening of existing gamma' precipitates can be slow at these temperatures, yet potentially significant for anticipated disk service times exceeding 1,000 h. The ability to quantify and predict such potential phase instabilities and degradation of capabilities is needed to insure structural integrity and air worthiness of propulsion systems over the full life cycle. A prototypical advanced disk superalloy was subjected to high temperature exposures, and then evaluated. Microstructural changes and corresponding changes in mechanical properties were quantified. The results will be compared to predictions of microstructure modeling software.

  3. Powder metallurgy: Solid and liquid phase sintering of copper

    Science.gov (United States)

    Sheldon, Rex; Weiser, Martin W.

    1993-01-01

    Basic powder metallurgy (P/M) principles and techniques are presented in this laboratory experiment. A copper based system is used since it is relatively easy to work with and is commercially important. In addition to standard solid state sintering, small quantities of low melting metals such as tin, zinc, lead, and aluminum can be added to demonstrate liquid phase sintering and alloy formation. The Taguchi Method of experimental design was used to study the effect of particle size, pressing force, sintering temperature, and sintering time. These parameters can be easily changed to incorporate liquid phase sintering effects and some guidelines for such substitutions are presented. The experiment is typically carried out over a period of three weeks.

  4. Powder metallurgy and mechanical alloying effects on the formation of thermally induced martensite in an FeMnSiCrNi SMA

    Directory of Open Access Journals (Sweden)

    Pricop Bogdan

    2015-01-01

    Full Text Available By ingot metallurgy (IM, melting, alloying and casting, powder metallurgy (PM, using as-blended elemental powders and mechanical alloying (MA of 50 % of particle volume, three types of FeMnSiCrNi shape memory alloy (SMA specimens were fabricated, respectively. After specimen thickness reduction by hot rolling, solution treatments were applied, at 973 and 1273 K, to thermally induce martensite. The resulting specimens were analysed by X-ray diffraction (XRD and scanning electron microscopy (SEM, in order to reveal the presence of ε (hexagonal close-packed, hcp and α’ (body centred cubic, bcc thermally induced martensites. The reversion of thermally induced martensites, to γ (face centred cubic, fcc austenite, during heating, was confirmed by dynamic mechanical analysis (DMA, which emphasized marked increases of storage modulus and obvious internal friction maxima on DMA thermograms. The results proved that the increase of porosity degree, after PM processing, increased internal friction, while MA enhanced crystallinity degree.

  5. Comprehensive waste characterization and organic pollution co-occurrence in a Hg and As mining and metallurgy brownfield.

    Science.gov (United States)

    Gallego, J R; Esquinas, N; Rodríguez-Valdés, E; Menéndez-Aguado, J M; Sierra, C

    2015-12-30

    The abandonment of Hg-As mining and metallurgy sites, together with long-term weathering, can dramatically degrade the environment. In this work it is exemplified the complex legacy of contamination that afflicts Hg-As brownfields through the detailed study of a paradigmatic site. Firstly, an in-depth study of the former industrial process was performed to identify sources of different types of waste. Subsequently, the composition and reactivity of As- and Hg-rich wastes (calcines, As-rich soot, stupp, and flue dust) was analyzed by means of multielemental analysis, mineralogical characterization (X-ray diffraction, electronic, and optical microscopy, microbrobe), chemical speciation, and sequential extractions. As-rich soot in the form of arsenolite, a relatively mobile by-product of the pyrometallurgical process, and stupp, a residue originated in the former condensing system, were determined to be the main risk at the site. In addition, the screening of organic pollution was also aimed, as shown by the outcome of benzo(a) pyrene and other PAHs, and by the identification of unexpected Hg organo-compounds (phenylmercury propionate). The approach followed unravels evidence from waste from the mining and metallurgy industry that may be present in other similar sites, and identifies unexpected contaminants overlooked by conventional analyses. Copyright © 2015 Elsevier B.V. All rights reserved.

  6. Uranium mining and metallurgy library information service under the network environment

    International Nuclear Information System (INIS)

    Tang Lilei

    2012-01-01

    This paper analyzes the effect of the network environment on the uranium mining and metallurgy of the information service. Introduces some measures such as strengthening professional characteristic literature resources construction, changing the service mode, building up information navigation, deepening service, meet the individual needs of users, raising librarian's quality, promoting the co-construction and sharing of library information resources, and puts forward the development idea of uranium mining and metallurgy library information service under the network environment. (author)

  7. Development and application of characteristic database for uranium mining and metallurgy in the library of Beijing Research Institute of Chemical Engineering and Metallurgy

    International Nuclear Information System (INIS)

    Gao Renxi

    2012-01-01

    Beijing Research Institute of Chemical Engineering and Metallurgy (BRICEM) is a multi disciplinary comprehensive research institute engaged in uranium mining, engineering design and related material researches. After 53 years of researches and development, BRICEM has accumulated a plenty of valuable data and resources. By analyzing the actual conditions of BRICEM's technological database, this thesis aims to propose the idea of building a characteristic database for uranium mining and metallurgy. It gives an in-depth analysis on content design, development status and problems of database development, in order to come up with solutions to these problems, as well as suggestions on the future development plans of the characteristic database. (author)

  8. Isolation and characterization of ferrous- and sulfur-oxidizing bacteria from Tengchong solfataric region, China.

    Science.gov (United States)

    Jiang, Chengying; Liu, Ying; Liu, Yanyang; Guo, Xu; Liu, Shuang-Jiang

    2009-01-01

    Microbial oxidation and reduction of iron and sulfur are important parts of biogeochemical cycles in acidic environments such as geothermal solfataric regions. Species of Acidithiobacillus and Leptospirillum are the common ferrous-iron and sulfur oxidizers from such environments. This study focused on the Tengchong sofataric region, located in Yunnan Province, Southwest China. Based on cultivation, 9 strains that grow on ferrous-iron and sulfuric compounds were obtained. Analysis of 16S rRNA genes of the 9 strains indicated that they were affiliated to Acidithiobacillus, Alicyclobacillus, Sulfobacillus, Leptospirillum and Acidiphilium. Physiological and phylogenetic studies indicated that two strains (TC-34 and TC-71) might represent two novel members of Alicyclobacillus. Strain TC-34 and TC-71 showed 94.8%-97.1% 16S rRNA gene identities to other species of Alicyclobacillus. Different from the previously described Alicyclobacillus species, strains TC-34 and TC-71 were mesophilic and their cellular fatty acids do not contain omega-cyclic fatty acids. Strain TC-71 was obligately dependent on ferrous-iron for growth. It was concluded that the ferrous-iron oxidizers were diversified and Alicyclobacillus species were proposed to take part in biochemical geocycling of iron in the Tengchong solfataric region.

  9. A novel reverse osmosis membrane by ferrous sulfate assisted controlled oxidation of polyamide layer

    Science.gov (United States)

    Raval, Hiren D.; Raviya, Mayur R.; Gauswami, Maulik V.

    2017-11-01

    With growing desalination capacity, it is very important to evaluate the performance of thin film composite reverse osmosis (TFC RO) membrane in terms of energy consumption for desalination. There is a trade-off between salt rejection and water-flux of TFC RO membrane. This article presents a novel approach of analyzing the effect of mixture of an oxidizing agent sodium hypochlorite and a reducing agent ferrous sulfate on virgin TFC RO membrane. Experiments were carried out by varying the concentrations of both sodium hypochlorite and ferrous sulfate. The negative charge was induced on the membrane due to the treatment of combination of sodium hypochlorite and ferrous sulfate, thereby resulting in higher rejection of negative ions due to repulsive force. Membrane treated with 1000 mg l-1 sodium hypochlorite and 2000 mg l-1 ferrous sulfate showed the best salt rejection i.e. 96.23%. The characterization was carried out to understand the charge on the membrane surface by Zeta potential, morphology of membrane surface by scanning electron microscope (SEM), surface roughness features by atomic force microscope (AFM) and chemical structural changes by nuclear magnetic resonance (NMR) analysis.

  10. The effect of initial pH on the kinetics of ferrous-iron biooxidation at ...

    African Journals Online (AJOL)

    The general understanding in bioleaching of sulphide minerals is to keep pH low. A number of published articles have reported the effect of pH on biooxidation rates of ferrous-iron and/or sulphur by bioleaching microbes, although most of these studies were conducted at optimum or near optimum temperature for microbial ...

  11. Compatibility of Anti-Wear Additives with Non-Ferrous Engine Bearing Alloys

    Energy Technology Data Exchange (ETDEWEB)

    Qu, Jun [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Zhou, Yan [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)

    2017-01-01

    Investigate the compatibility of engine lubricant antiwear (AW) additives, specifically conventional zinc dialkyldithiophosphate (ZDDP) and newly developed ionic liquids (ILs), with selected non-ferrous engine bearing alloys, specifically aluminum and bronze alloys that are commonly used in connecting rod end journal bearings and bushings, to gain fundamental understanding to guide future development of engine lubricants

  12. Part 5: Experimental periods using a ferrous-ferric chloride blend

    African Journals Online (AJOL)

    drinie

    A blend of ferrous chloride and ferric chloride (FeCl2-FeCl3) was simultaneously dosed into an activated sludge system at .... theoretical oxygen demand for this reaction is small, namely 0.15 ...... The role of bacterial extracellular polymers.

  13. Energy conservation and efficiency in Giprokoks designs at Ukrainian ferrous-metallurgical enterprises

    Energy Technology Data Exchange (ETDEWEB)

    M.I. Fal' kov [Giprokoks, the State Institute for the Design of Coke-Industry Enterprises, Kharkov (Ukraine)

    2009-07-15

    Energy conditions at Ukrainian ferrous-metallurgical enterprises are analyzed. Measures to boost energy conservation and energy efficiency are proposed: specifically, the introduction of systems for dry slaking of coke; and steam-gas turbines that employ coke-oven gas or a mixture of gases produced at metallurgical enterprises. Such turbines may be built from Ukrainian components.

  14. Price variability and marketing method in non-ferrous metals: Slade's analysis revisited

    NARCIS (Netherlands)

    Gilbert, C.L.; Ferretti, F.

    2002-01-01

    We examine the impact of the pricing regime on price variability with reference to the non-ferrous metals industry. Theoretical arguments are ambiguous, but suggest that the extent of monopoly power is more important than the pricing regime as a determinant of variability. Slade (Quart. J. Econ. 106

  15. Stabilization of Pb and As in soils by applying combined treatment with phosphates and ferrous iron.

    Science.gov (United States)

    Xenidis, Anthimos; Stouraiti, Christina; Papassiopi, Nymphodora

    2010-05-15

    The chemical immobilization of Pb and As in contaminated soil from Lavrion, Greece, using monocalcium phosphate and ferrous sulfate as stabilizing agents was investigated. Monocalcium phosphate was added to contaminated soil at PO(4) to Pb molar ratios equal to 0, 0.5, 1, 1.5 and 2.5, whereas ferrous sulfate was added at Fe to As molar ratios equal to 0, 2.5, 5, 10 and 20. Phosphates addition to contaminated soil decreased Pb leachability, but resulted in significant mobilization of As. Simultaneous immobilization of Pb and As was obtained only when soil was treated with mixtures of phosphates and ferrous sulfate. Arsenic uptake by plants was also seen to increase when soil was treated only with phosphates, but co-addition of ferrous sulfate was efficient in maintaining As phytoaccumulation at low levels. The addition of at least 1.5M/M phosphates and 10M/M iron sulfate to soil reduced the dissolved levels of Pb and As in the water extracts to values in compliance with the EU drinking water standards. However, both additives contributed in the acidification of soil, decreasing pH from 7.8 to values as low as 5.6 and induced the mobilization of pH sensitive elements, such as Zn and Cd. Copyright (c) 2010 Elsevier B.V. All rights reserved.

  16. Laser photothermal non-destructive metrology of cracks in un-sintered powder metallurgy manufactured automotive transmission sprockets

    International Nuclear Information System (INIS)

    Tolev, J; Mandelis, A

    2010-01-01

    A non-contact and non-intrusive method of revealing crack presence in un-sintered (green) automotive transmission parts (sprockets), manufactured by means of a powder metallurgy technology based on analysis of photo-thermal radiometric (PTR) signals and their statistical analysis was developed. The inspection methodology relies on the interaction of a modulated laser generated thermal wave with the potential crack and the resulting change in amplitude and phase of the detected signal [1-5]. The crack existence at points in high stress regions of a group of green (unsintered) sprockets was evaluated through frequency scans. The results were validated by independent destructive cross-sectioning of the sprockets following sintering and polishing. Examination of the sectioned sprockets under a microscope at the locations where signal changes was used for correlation with the PTR signals. Statistical analysis confirmed the capabilities of the method to detect the presence of hairline cracks (∼5 - 10 μm size) with excellent sensitivity (91%) and good accuracy (78%) and specificity (61%). This measurement technique and the associated statistical analysis can be used as a simple and reliable on-line inspection methodology of industrial powder metallurgy manufactured steel products for non-destructive quality and feedback control of the parts forming process.

  17. Indoor atmospheric corrosion of historical ferrous alloys. System characterisation, mechanisms and modelling discussion

    International Nuclear Information System (INIS)

    Monnier, J.

    2008-12-01

    Understanding the mechanisms of indoor atmospheric corrosion in iron alloys is of primary importance in several fields, including for the conservation of Middle Ages monuments or the long term storage of nuclear waste. In this research, a double approach was developed, combining fine characterisation of corrosion systems and design of experiments to answers specific questions related to mechanisms understanding. Iron indoor atmospheric corrosion was investigated on samples coming from the reinforcing chain of the Amiens cathedral (15. century). In the first stage, the corrosion system has been extensively characterised from the macroscopic to the nano-metric scale. In particular, structural micro-analysis (μ-Raman, μ-XRD, μ-XAS) has been used to locate, identify and quantify the oxidised phases. Rust layers are composed of a matrix of nano-metric goethite, with low quantities of lepidocrocite and akaganeite mostly located in the extern part of the corrosion system. In addition, clear marblings are dispersed in the matrix, which are sometimes connected with the metal core. Although these may contain maghemite, these marblings are generally made of ferri-hydrite/feroxyhite phases. In the second stage, specific experiments have been carried out in an unsaturated marked medium to locate oxygen reduction sites in the rust layers. Several cases were evidenced, depending on the rust layer morphology. In addition, reduction processes of model phases have been studied in situ, using an electrochemical cell coupled with structural characterisation techniques. This combination highlighted the influence of reduction mode and pH on the type of reduced phase formed. From the obtained results, several mechanisms are proposed to explain the long term indoor atmospheric corrosion of iron, including rust layers morphology and phases properties. The different hypotheses have been integrated in a proposed method to diagnosis ancient ferrous systems stability. These hypotheses also

  18. Estimation and characterization of PCDD/Fs, dl-PCBs, PCNs, HxCBz and PeCBz emissions from magnesium metallurgy facilities in China.

    Science.gov (United States)

    Nie, Zhiqiang; Zheng, Minghui; Liu, Wenbin; Zhang, Bing; Liu, Guorui; Su, Guijin; Lv, Pu; Xiao, Ke

    2011-12-01

    Magnesium production is considered to be one potential source of unintentional persistent organic pollutants (unintentional POPs). However, studies on the emissions of unintentional POPs from magnesium metallurgy are still lacking. Emissions of unintentional POPs, such as polychlorinated dibenzo-p-dioxins/dibenzofurans (PCDD/Fs), dioxin-like polychlorinated biphenyls (dl-PCBs), polychlorinated naphthalenes (PCNs), hexachlorobenzene (HxCBz) and pentachlorobenzene (PeCBz) are covered under the Stockholm Convention. In this study, these emissions were investigated through a magnesium smelting process. Stack gas and fly ash samples from a typical magnesium plant in China were collected and analyzed to estimate the emissions of unintentional POPs from magnesium metallurgy. Emissions factors of 412 ng TEQ t(-1) for PCDD/Fs, 18.6 ng TEQ t(-1) for dl-PCBs, 3329 μg t(-1) for PCNs, 820 μg t(-1) for HxCBz, and 1326 μg t(-1) for PeCBz were obtained in 2009. Annual emissions from magnesium metallurgy in China were estimated to be 0.46 g WHO-TEQ for PCDD/Fs and dl-PCBs, 1651 g for PCNs, 403 g for HxCBz and 653 g for PeCBz, respectively. Copyright © 2011 Elsevier Ltd. All rights reserved.

  19. The Effect of Forging Variables on the Supersolvus Heat-Treatment Response of Powder-Metallurgy Nickel-Base Superalloys

    Science.gov (United States)

    2014-12-01

    AFRL-RX-WP-JA-2015-0160 THE EFFECT OF FORGING VARIABLES ON THE SUPERSOLVUS HEAT-TREATMENT RESPONSE OF POWDER - METALLURGY NICKEL-BASE SUPERALLOYS... POWDER - METALLURGY NICKEL- BASE SUPERALLOYS (POSTPRINT) 5a. CONTRACT NUMBER In-house 5b. GRANT NUMBER 5c. PROGRAM ELEMENT NUMBER 62102F 6. AUTHOR...treatment (SSHT) of two powder - metallurgy , gamma–gamma prime superalloys, IN-100 and LSHR, was established. For this purpose, isothermal, hot

  20. Reuse of beneficiency residue from mining and metallurgy as source of zeolites

    International Nuclear Information System (INIS)

    Souza, J.A.S.; Rodrigues, E.C.; Souza, J.A.S.; Neves, R.F.; Macedo, E.N.; Moraes, C.G.

    2011-01-01

    The mining industry and metallurgy, located in Para State, brought the concern about the huge generation of solid waste (eg The Red Mud (LV) industry Alumina; waste alumina sand-kaolin industry, waste of cuba electrolytic aluminum industry and other metal) and with the gas emissions from the burning of fossil fuels these industries. In the case of solid waste, most of which require special care such as check dams and even storage areas protected. Since the waste gases are not always properly treated and are one of the most discussed environmental problem today, according to the emission of compounds such as SOx, NOx, Cox's treatment of these effluents should be given, necessarily involves techniques of adsorption followed by reaction neutralization. These techniques can be used in two ways: by wet and dry. In the specific case of gas emissions from fossil fuels is used to wash using aqueous suspensions of calcium oxide. In this context, studies conducted in the Laboratory of Ceramic Materials, UFPA [1, 2], showed that the Bayer process residue (red mud) has characteristics that indicate the possibility of its use in place of calcium oxide in the treatment of waste gases. Moreover, waste from kaolin industry can be used as adsorbents since they go through a process of synthesis, producing different types of synthetic zeolites can be extremely useful in the treatment of waste and various activities related to environmental issues. (author)

  1. Anodization Mechanism on SiC Nanoparticle Reinforced Al Matrix Composites Produced by Power Metallurgy

    Directory of Open Access Journals (Sweden)

    Sonia C. Ferreira

    2014-12-01

    Full Text Available Specimens of aluminum-based composites reinforced by silicon carbide nanoparticles (Al/SiCnp produced by powder metallurgy (PM were anodized under voltage control in tartaric-sulfuric acid (TSA. In this work, the influence of the amount of SiCnp on the film growth during anodizing was investigated. The current density versus time response and the morphology of the porous alumina film formed at the composite surface are compared to those concerning a commercial aluminum alloy (AA1050 anodized under the same conditions. The processing method of the aluminum alloys influences the efficiency of the anodizing process, leading to a lower thicknesses for the unreinforced Al-PM alloy regarding the AA1050. The current density versus time response is strongly dependent on the amount of SiCnp. The current peaks and the steady-state current density recorded at each voltage step increases with the SiCnp volume fraction due to the oxidation of the SiCnp. The formation mechanism of the anodic film on Al/SiCnp composites is different from that occurring in AA1050, partly due the heterogeneous distribution of the reinforcement particles in the metallic matrix, but also to the entrapment of SiCnp in the anodic film.

  2. Anodization Mechanism on SiC Nanoparticle Reinforced Al Matrix Composites Produced by Power Metallurgy

    Science.gov (United States)

    Ferreira, Sonia C.; Conde, Ana; Arenas, María A.; Rocha, Luis A.; Velhinho, Alexandre

    2014-01-01

    Specimens of aluminum-based composites reinforced by silicon carbide nanoparticles (Al/SiCnp) produced by powder metallurgy (PM) were anodized under voltage control in tartaric-sulfuric acid (TSA). In this work, the influence of the amount of SiCnp on the film growth during anodizing was investigated. The current density versus time response and the morphology of the porous alumina film formed at the composite surface are compared to those concerning a commercial aluminum alloy (AA1050) anodized under the same conditions. The processing method of the aluminum alloys influences the efficiency of the anodizing process, leading to a lower thicknesses for the unreinforced Al-PM alloy regarding the AA1050. The current density versus time response is strongly dependent on the amount of SiCnp. The current peaks and the steady-state current density recorded at each voltage step increases with the SiCnp volume fraction due to the oxidation of the SiCnp. The formation mechanism of the anodic film on Al/SiCnp composites is different from that occurring in AA1050, partly due the heterogeneous distribution of the reinforcement particles in the metallic matrix, but also to the entrapment of SiCnp in the anodic film. PMID:28788295

  3. Cooling γ precipitation behavior and strengthening in powder metallurgy superalloy FGH4096

    Institute of Scientific and Technical Information of China (English)

    TIAN Gaofeng; JIA Chengchang; WEN Yin; LIU Guoquan; HU Benfu

    2008-01-01

    Two cooling schemes (continuous cooling and interrupted cooling tests) were applied to investigate the cooling γ precipitation behavior in powder metallurgy superalloy FGH4096.The effect of cooling rate on cooling γ precipitation and the development of γ precipitates during cooling process were involved in this study.The ultimate tensile strength (UTS) of the specimens in various cooling circumstances was tested.The experiential equations were obtained between the average sizes of secondary and tertiary γ precipitates,the strength,and cooling rate.The results show that they are inversely correlated with the cooling rate as well as the grain boundary changes from serrated to straight,the shape of secondary γ precipitates changes from irregular cuboidal to spherical,while the formed tertiary γ precipitates are always spherical.The interrupted cooling tests show that the average size of secondary γ precipitates increases as a linear function of interrupt temperature for a fixed cooling rate of 24℃/min.The strength first decreases and then increases against interrupt temperature,which is fundamentally caused by the multistage nucleation of γ precipitates during cooling process.

  4. Innovative technologies for powder metallurgy-based disk superalloys: Progress and proposal

    Science.gov (United States)

    Chong-Lin, Jia; Chang-Chun, Ge; Qing-Zhi, Yan

    2016-02-01

    Powder metallurgy (PM) superalloys are an important class of high temperature structural materials, key to the rotating components of aero engines. In the purview of the present challenges associated with PM superalloys, two novel approaches namely, powder preparation and the innovative spray-forming technique (for making turbine disk) are proposed and studied. Subsequently, advanced technologies like electrode-induction-melting gas atomization (EIGA), and spark-plasma discharge spheroidization (SPDS) are introduced, for ceramic-free superalloy powders. Presently, new processing routes are sought after for preparing finer and cleaner raw powders for disk superalloys. The progress of research in spray-formed PM superalloys is first summarized in detail. The spray-formed superalloy disks specifically exhibit excellent mechanical properties. This paper reviews the recent progress in innovative technologies for PM superalloys, with an emphasis on new ideas and approaches, central to the innovation driving techniques like powder processing and spray forming. Project supported by the National Natural Science Foundation of China (Grant Nos. 50974016 and 50071014).

  5. Spray forming and mechanical properties of a new type powder metallurgy superalloy

    International Nuclear Information System (INIS)

    Jia Chong-Lin; Ge Chang-Chun; Xia Min; Gu Tian-Fu

    2015-01-01

    The deposited billet of a new type powder metallurgy (PM) superalloy FGH4095M for use in turbine disk manufacturing has been fabricated using spray forming technology. The metallurgical quality of the deposited billet was analyzed in terms of density, texture, and grain size. Comparative research was done on the microstructure and mechanical properties between the flat disk preform prepared with hot isostatic pressing (HIP) and the same alloy forgings prepared with HIP followed by isothermal forging (IF). The results show that the density of the spray-formed and nitrogen-atomized deposit billet is above 99% of the theoretical density, indicating a compact structure. The grains are uniform and fine. The billet has weak texture with a random distribution in the spray deposition direction and perpendicular to the direction of deposition. A part of atomizing nitrogen exists in the preform in the form of carbonitride. Nitrogen-induced microporosity causes the density reduction of the preform. Compared with the process of HIP+IF, the superalloy FGH4095M after HIP has better mechanical properties at both room temperature and high temperature. The sizes of the γ′ phase are finer in microstructure of the preform after HIP in comparison with the forgings after HIP+IF. This work shows that SF+HIP is a viable processing route for FGH4095M as a turbine-disk material. (paper)

  6. State-of-the-art of recycling e-wastes by vacuum metallurgy separation.

    Science.gov (United States)

    Zhan, Lu; Xu, Zhenming

    2014-12-16

    In recent era, more and more electric and electronic equipment wastes (e-wastes) are generated that contain both toxic and valuable materials in them. Most studies focus on the extraction of valuable metals like Au, Ag from e-wastes. However, the recycling of metals such as Pb, Cd, Zn, and organics has not attracted enough attentions. Vacuum metallurgy separation (VMS) processes can reduce pollution significantly using vacuum technique. It can effectively recycle heavy metals and organics from e-wastes in an environmentally friendly way, which is beneficial for both preventing the heavy metal contaminations and the sustainable development of resources. VMS can be classified into several methods, such as vacuum evaporation, vacuum carbon reduction and vacuum pyrolysis. This paper respectively reviews the state-of-art of these methods applied to recycling heavy metals and organics from several kinds of e-wastes. The method principle, equipment used, separating process, optimized operating parameters and recycling mechanism of each case are illustrated in details. The perspectives on the further development of e-wastes recycling by VMS are also presented.

  7. Anodization Mechanism on SiC Nanoparticle Reinforced Al Matrix Composites Produced by Power Metallurgy.

    Science.gov (United States)

    Ferreira, Sonia C; Conde, Ana; Arenas, María A; Rocha, Luis A; Velhinho, Alexandre

    2014-12-19

    Specimens of aluminum-based composites reinforced by silicon carbide nanoparticles (Al/SiC np ) produced by powder metallurgy (PM) were anodized under voltage control in tartaric-sulfuric acid (TSA). In this work, the influence of the amount of SiC np on the film growth during anodizing was investigated. The current density versus time response and the morphology of the porous alumina film formed at the composite surface are compared to those concerning a commercial aluminum alloy (AA1050) anodized under the same conditions. The processing method of the aluminum alloys influences the efficiency of the anodizing process, leading to a lower thicknesses for the unreinforced Al-PM alloy regarding the AA1050. The current density versus time response is strongly dependent on the amount of SiC np . The current peaks and the steady-state current density recorded at each voltage step increases with the SiC np volume fraction due to the oxidation of the SiC np . The formation mechanism of the anodic film on Al/SiC np composites is different from that occurring in AA1050, partly due the heterogeneous distribution of the reinforcement particles in the metallic matrix, but also to the entrapment of SiC np in the anodic film.

  8. Dwell Notch Low Cycle Fatigue Behavior of a Powder Metallurgy Nickel Disk Alloy

    Science.gov (United States)

    Telesman, J.; Gabb, T. P.; Yamada, Y.; Ghosn, L. J.; Jayaraman, N.

    2012-01-01

    A study was conducted to determine the processes which govern dwell notch low cycle fatigue (NLCF) behavior of a powder metallurgy (P/M) ME3 disk superalloy. The emphasis was placed on the environmentally driven mechanisms which may embrittle the highly stressed notch surface regions and reduce NLCF life. In conjunction with the environmentally driven notch surface degradation processes, the visco-plastic driven mechanisms which can significantly change the notch root stresses were also considered. Dwell notch low cycle fatigue testing was performed in air and vacuum on a ME3 P/M disk alloy specimens heat treated using either a fast or a slow cooling rate from the solutioning treatment. It was shown that dwells at the minimum stress typically produced a greater life debit than the dwells applied at the maximum stress, especially for the slow cooled heat treatment. Two different environmentally driven failure mechanisms were identified as the root cause of early crack initiation in the min dwell tests. Both of these failure mechanisms produced mostly a transgranular crack initiation failure mode and yet still resulted in low NLCF fatigue lives. The lack of stress relaxation during the min dwell tests produced higher notch root stresses which caused early crack initiation and premature failure when combined with the environmentally driven surface degradation mechanisms. The importance of environmental degradation mechanisms was further highlighted by vacuum dwell NLCF tests which resulted in considerably longer NLCF lives, especially for the min dwell tests.

  9. Indexation Rules for Metallurgy in PASCAL. Original Title: Regles d'Indexation de la Metallurgie'--Technical Note Issued by Informascience--January 1980. Translated by Marie Wallin.

    Science.gov (United States)

    Royal Inst. of Tech., Stockholm (Sweden). Library.

    The indexing rules presented are designed for use with a new French-German database on metallurgy being developed under an agreement by CNRS (Centre National de la Recherche Scientifique, Paris) and BAM (Bundesanstalt fur Materialprufung, Berlin). The new database, which will feature multilingual titles and index terms (French-German-English-) and…

  10. Alloy 800 - A review of properties and metallurgy

    International Nuclear Information System (INIS)

    Stone, P.G.; Orr, J.

    1976-01-01

    It is shown that the properties and metallurgy of alloy 800 are significantly influenced by relatively small changes in composition introduced by the nuclear industry in order to obtain better stress corrosion resistance. Two particular metallurgical effects are considered: the influence of lower TiC volume fraction on grain coarsening behavior and grain size; the influence of increased amounts of titanium in solid solution on Ni 3 (AlTi) precipitation. The first effect has a direct influence on proof stress properties, and the second on stress rupture strength and ductility. However, the important effect of aluminium on this behavior is emphasized. Other aspects considered are the effect of long reheating times during operation on proof strength and impact resistance. The final part of the paper deals with two fabrication aspects. After demonstrating the detrimental effect of cold working on stress rupture ductility, the susceptibility to premature failure is examined, using notched stress rupture specimens. Although notch sensitivity was found in short term tests, additional work suggests that it may not occur after longer testing times. The effect of stress relieving on this behavior is reported. The welding aspects considered include the compositional factors influencing liquation cracking, grain growth during welding, and the proof strength and stress rupture properties of welded material

  11. The traces of roman metallurgy in Eastern Serbia

    Directory of Open Access Journals (Sweden)

    Petković Sofija

    2009-01-01

    Full Text Available The archaeological traces of the Roman mining and metallurgy in eastern Serbia are rather frequent but insufficiently studied and published. Three mining-metallurgical regions abounding in gold, silver, copper, iron and lead could be distinguished there: 1. the upper course of the Pek river, metalla Pincensia, 2. the area between Bor, Zlot, Crna Reka and Rgotina and 3. the area in the river basin of Beli Timok, two latter ones had been organized as territoria metallorum. The archeometallurgical sites confirmed by investigations are: Kraku lu Jordan at the confluence of the Brodica river and the Pek river, Rudna Glava, Tilva Roš in Bor, Gamzigrad - Romuliana, Rgotina near Zaječar and Timacum Minus in the village Ravna near Knjaževac. Roman mining-metallurgical activities in eastern Serbia flourished from the end of the 3rd century, were interrupted by the invasion of Huns in AD 441. and restored in the time of emperors Anastasius and Justin I, in the end of the 5th - beginning of the 6th centuries. The Roman mining-metallurgical centers functioned in the 6th century until the Slav invasion in the beginning of the 7th century.

  12. Device for preparing combinatorial libraries in powder metallurgy.

    Science.gov (United States)

    Yang, Shoufeng; Evans, Julian R G

    2004-01-01

    This paper describes a powder-metering, -mixing, and -dispensing mechanism that can be used as a method for producing large numbers of samples for metallurgical evaluation or electrical or mechanical testing from multicomponent metal and cermet powder systems. It is designed to make use of the same commercial powders that are used in powder metallurgy and, therefore, to produce samples that are faithful to the microstructure of finished products. The particle assemblies produced by the device could be consolidated by die pressing, isostatic pressing, laser sintering, or direct melting. The powder metering valve provides both on/off and flow rate control of dry powders in open capillaries using acoustic vibration. The valve is simple and involves no relative movement, avoiding seizure with fine powders. An orchestra of such valves can be arranged on a building platform to prepare multicomponent combinatorial libraries. As with many combinatorial devices, identification and evaluation of sources of mixing error as a function of sample size is mandatory. Such an analysis is presented.

  13. [Possible health effects associated with Pre-Columbian metallurgy].

    Science.gov (United States)

    Idrovo, Alvaro Javier

    2005-09-01

    In the Old World, several researchers have indicated that adverse health effects were associated with exposure to arsenic, and that this influenced a change in the use of copper-arsenic alloys to others less toxic. This hypothesis was evaluated for three Pre-Columbian metallurgy traditions: Central Andes, Intermediate Area, and West Mexico. The metal artifacts from the Central Andes showed arsenic concentrations similar to those in the Old World (0.5%-1.0%). In the Intermediate Area the values were smallest; however, in West Mexico the arsenic content was very high (7%-25%). In Central Andes arsenical bronze was used initially, but copper-tin alloys when introduced were preferred and distributed throughout the Inca Empire. Osteological and artistic evidences of foot amputations among Moche individuals from Central Andes support the presence of "black foot disease" (a condition associated with arsenic poisoning) among Pre-Columbian populations. In conclusion, the adverse effects of arsenic have been observed in the New World, and that these effects promoted a change toward the use of less toxic alloys.

  14. Metallurgy of platinoids. Studies of industrial cases; Metallurgie des platinoides. Etudes de cas industriels

    Energy Technology Data Exchange (ETDEWEB)

    Blazy, P. [Ecole Nationale Superieure de Geologie, 54 - Vandoeuvre les Nancy (France); Jdid, E. A. [Institut National Polytechnique de Lorraine (ENSG/INPL/CNRS UMR 7569), 54 Vandoeuvre les Nancy (France)

    2004-03-01

    The platinoids deposits, currently in exploitation, are often associated with dunitic and gabbroitic ultra-basic rocks containing copper, nickel and iron sulfides. The proportion of platinoids in these deposits is variable and requires generally an adaptation of the industrial processes for their recovery. Nevertheless, we can consider that the classical industrial way consists to treat the composite concentrates of copper-nickel-platinoids sulfides by melting/conversion operations following by hydrometallurgical operations of recovery of the basic metals Cu, Ni. These last ones concentrate the platinoids in leaching residues. In these residues, the platinoids are extracted and separated by hydrometallurgical ways including different techniques: dissolution, selective precipitation, distillation, solvent extraction, resins...The great variety of uses of platinoids makes their recycling difficult. The wastes are often too complex for being economically recycling. The environmental protection depends of the type of industry (metallurgical, chemical, mining). Some products present risks of fire and explosion. The toxicity often appears by superficial allergies and by serious troubles in case of ingestion of soluble salts. (O.M.)

  15. Influence of cold rolling and strain rate on plastic response of powder metallurgy and chemical vapor deposition rhenium

    International Nuclear Information System (INIS)

    Koeppel, B.J.; Subhash, G.

    1999-01-01

    The plastic response of two kinds of rhenium processed via powder metallurgy (PM) and chemical vapor deposition (CVD) were investigated under uniaxial compression over a range of strain rates. The PM rhenium, further cold rolled to 50 and 80 pct of the original thickness, was also investigated to assess the influence of cold work on the plastic behavior. A strong basal texture was detected in all the preceding materials as a result of processing and cold work. Both CVD and PM rhenium exhibited an increase in yield strength and flow stress with increasing strain rate. In PM rhenium, cold work resulted in an increase in hardness and yield strength and a decrease in the work hardening rate. The deformed microstructures revealed extensive twinning in CVD rhenium. At large strains, inhomogeneous deformation mode in the form of classical cup and cone fracture was noticed

  16. Compressibility of 304 Stainless Steel Powder Metallurgy Materials Reinforced with 304 Short Stainless Steel Fibers

    Directory of Open Access Journals (Sweden)

    Bibo Yao

    2016-03-01

    Full Text Available Powder metallurgy (P/M technique is usually used for manufacturing porous metal materials. However, some P/M materials are limitedly used in engineering for their performance deficiency. A novel 304 stainless steel P/M material was produced by a solid-state sintering of 304 stainless steel powders and 304 short stainless steel fibers, which were alternately laid in layers according to mass ratio. In this paper, the compressive properties of the P/M materials were characterized by a series of uniaxial compression tests. The effects of fiber content, compaction pressure and high temperature nitriding on compressive properties were investigated. The results indicated that, without nitriding, the samples changed from cuboid to cydariform without damage in the process of compression. The compressive stress was enhanced with increasing fiber content ranging from 0 to 8 wt.%. For compaction pressure from 55 to 75 MPa, greater compaction pressure improved compressive stress. Moreover, high temperature nitriding was able to significantly improve the yield stress, but collapse failure eventually occurred.

  17. Application of powder metallurgy technique to produce improved bearing elements for cryogenic aerospace engine turbopumps

    Science.gov (United States)

    Moxson, V. S.; Moracz, D. J.; Bhat, B. N.; Dolan, F. J.; Thom, R.

    1987-01-01

    Traditionally, vacuum melted 440C stainless steel is used for high performance bearings for aerospace cryogenic systems where corrosion due to condensation is a major concern. For the Space Shuttle Main Engine (SSME), however, 440C performance in the high-pressure turbopumps has been marginal. A basic assumption of this study was that powder metallurgy, rather than cast/wrought, processing would provide the finest, most homogeneous bearing alloy structure. Preliminary testing of P/M alloys (hardness, corrosion resistance, wear resistance, fatigue resistance, and fracture toughness) was used to 'de-select' alloys which did perform as well as baseline 440C. Five out of eleven candidate materials (14-4/6V, X-405, MRC-2001, T-440V, and D-5) based on preliminary screening were selected for the actual rolling-sliding five-ball testing. The results of this test were compared with high-performance vacuum-melted M50 bearing steel. The results of the testing indicated outstanding performance of two P/M alloys, X-405 and MRC-2001, which eventually will be further evaluated by full-scale bearing testing.

  18. Evaluation of the mechanical properties of powder metallurgy Ti-6Al-7Nb alloy.

    Science.gov (United States)

    Bolzoni, L; Ruiz-Navas, E M; Gordo, E

    2017-03-01

    Titanium and its alloys are common biomedical materials owing to their combination of mechanical properties, corrosion resistance and biocompatibility. Powder metallurgy (PM) techniques can be used to fabricate biomaterials with tailored properties because changing the processing parameters, such as the sintering temperature, products with different level of porosity and mechanical performances can be obtained. This study addresses the production of the biomedical Ti-6Al-7Nb alloy by means of the master alloy addition variant of the PM blending elemental approach. The sintering parameters investigated guarantee that the complete diffusion of the alloying elements and the homogenization of the microstructure is achieved. The sintering of the Ti-6Al-7Nb alloy induces a total shrinkage between 7.4% and 10.7% and the level of porosity decreases from 6.2% to 4.7% with the increment of the sintering temperature. Vickers hardness (280-300 HV30) and tensile properties (different combination of strength and elongation around 900MPa and 3%) are achieved. Copyright © 2016 Elsevier Ltd. All rights reserved.

  19. Factors Influencing Dwell Fatigue Cracking in Notches of Powder Metallurgy Superalloys

    Science.gov (United States)

    Gabb, T. P.; Telesman, J.; Ghosn, L.; Garg, A.; Gayda, J.

    2011-01-01

    The influences of heat treatment and cyclic dwells on the notch fatigue resistance of powder metallurgy disk superalloys were investigated for low solvus high refractory (LSHR) and ME3 disk alloys. Disks were processed to produce material conditions with varied microstructures and associated mechanical properties. Notched specimens were first subjected to baseline dwell fatigue cycles having a dwell at maximum load, as well as tensile, stress relaxation, creep rupture, and dwell fatigue crack growth tests at 704 C. Several material heat treatments displayed a bimodal distribution of fatigue life with the lives varying by two orders-of-magnitude, while others had more consistent fatigue lives. This response was compared to other mechanical properties, in search of correlations. The wide scatter in baseline dwell fatigue life was observed only for material conditions resistant to stress relaxation. For selected materials and conditions, additional tests were then performed with the dwells shifted in part or in total to minimum tensile load. The tests performed with dwells at minimum load exhibited lower fatigue lives than max dwell tests, and also exhibited early crack initiation and a substantial increase in the number of initiation sites. These results could be explained in part by modeling evolution of peak stresses in the notch with continued dwell fatigue cycling. Fatigue-environment interactions were determined to limit life for the fatigue cycles with dwells.

  20. Compressibility of 304 Stainless Steel Powder Metallurgy Materials Reinforced with 304 Short Stainless Steel Fibers.

    Science.gov (United States)

    Yao, Bibo; Zhou, Zhaoyao; Duan, Liuyang; Xiao, Zhiyu

    2016-03-04

    Powder metallurgy (P/M) technique is usually used for manufacturing porous metal materials. However, some P/M materials are limitedly used in engineering for their performance deficiency. A novel 304 stainless steel P/M material was produced by a solid-state sintering of 304 stainless steel powders and 304 short stainless steel fibers, which were alternately laid in layers according to mass ratio. In this paper, the compressive properties of the P/M materials were characterized by a series of uniaxial compression tests. The effects of fiber content, compaction pressure and high temperature nitriding on compressive properties were investigated. The results indicated that, without nitriding, the samples changed from cuboid to cydariform without damage in the process of compression. The compressive stress was enhanced with increasing fiber content ranging from 0 to 8 wt.%. For compaction pressure from 55 to 75 MPa, greater compaction pressure improved compressive stress. Moreover, high temperature nitriding was able to significantly improve the yield stress, but collapse failure eventually occurred.

  1. Residual Stresses in a NiCrY-Coated Powder Metallurgy Disk Superalloy

    Science.gov (United States)

    Gabb, Timothy P.; Rogers, Richard B.; Nesbitt, James A.; Puleo, Bernadette J.; Miller, Robert A.; Telesman, Ignacy; Draper, Susan L.; Locci, Ivan E.

    2017-01-01

    Protective ductile coatings will be necessary to mitigate oxidation and corrosion attack on superalloy disks exposed to increasing operating temperatures in some turbine engine environments. However, such coatings must be resistant to harmful surface cracking during service. The objective of this study was to investigate how residual stresses evolve in such coatings. Cylindrical gage fatigue specimens of powder metallurgy-processed disk superalloy LSHR were coated with a NiCrY coating, shot peened, and then subjected to fatigue in air at room and high temperatures. The effects of shot peening and fatigue cycling on average residual stresses and other aspects of the coating were assessed. Shot peening did induce beneficial compressive residual stresses in the coating and substrate. However, these stresses became more tensile in the coating with subsequent heating and contributed to cracking of the coating in long intervals of cycling at 760 C. Substantial compressive residual stresses remained in the substrate adjacent to the coating, sufficient to suppress fatigue cracking. The coating continued to protect the substrate from hot corrosion pitting, even after fatigue cracks initiated in the coating.

  2. [Atmospheric emission of PCDD/Fs from secondary aluminum metallurgy industry in the southwest area, China].

    Science.gov (United States)

    Lu, Yi; Zhang, Xiao-Ling; Guo, Zhi-Shun; Jian, Chuan; Zhu, Ming-Ji; Deng, Li; Sun, Jing; Zhang, Qin

    2014-01-01

    Five secondary aluminum metallurgy enterprises in the southwest area of China were measured for emissions of PCDD/Fs. The results indicated that the emission levels of PCDD/Fs (as TEQ) were 0.015-0.16 ng x m(-3), and the average was 0.093 ng x m(-3) from secondary aluminum metallurgy enterprises. Emission factors of PCDD/Fs (as TEQ) from the five secondary aluminum metallurgy enterprises varied between 0.041 and 4.68 microg x t(-1) aluminum, and the average was 2.01 microg x t(-1) aluminum; among them, PCDD/Fs emission factors from the crucible smelting furnace was the highest. Congener distribution of PCDD/F in stack gas from the five secondary aluminum metallurgies was very different from each other. Moreover, the R(PCDF/PCDD) was the lowest in the enterprise which was installed only with bag filters; the R(PCDF/PCDD) were 3.8-12.6 (the average, 7.7) in the others which were installed with water scrubbers. The results above indicated that the mechanism of PCDD/Fs formation was related to the types of exhaust gas treatment device. The results of this study can provide technical support for the formulation of PCDD/Fs emission standards and the best available techniques in the secondary aluminum metallurgy industry.

  3. Mathematical model of the oxidation of ferrous iron by a biofilm of Thiobacillus ferrooxidans.

    Science.gov (United States)

    Mesa, M M; Macías, M; Cantero, D

    2002-01-01

    Microbial oxidation of ferrous iron may be a viable alternative method of producing ferric sulfate, which is a reagent used for removal of H(2)S from biogas. The paper introduces a kinetic study of the biological oxidation of ferrous iron by Thiobacillus ferrooxidans immobilized on biomass support particles (BSP) composed of polyurethane foam. On the basis of the data obtained, a mathematical model for the bioreactor was subsequently developed. In the model described here, the microorganisms adhere by reversible physical adsorption to the ferric precipitates that are formed on the BSP. The model can also be considered as an expression for the erosion of microorganisms immobilized due to the agitation of the medium by aeration.

  4. Ferrous arrowheads and their oil quench hardening: Some early Indian evidence

    Science.gov (United States)

    Dube, R. K.

    2008-05-01

    A wide variety of ferrous arrowheads were in use in ancient India. Several typical chemical analyses of arrowheads found from archaeological excavation carried out at Kaushambi are reported in this paper. The average carbon content of these arrowheads varied from as low as 0.1 wt.% to approximately 0.9 wt.%. Literary evidence for oil quench hardening of ferrous arrowheads, as reported in famous Sanskrit epics—the Rāmāyana and the Mahābhārata—have been discussed in this paper. This type of quench hardening was intentionally adopted as it helped in preventing distortion and formation of quench cracks in arrowheads. The oil quench-hardened arrowheads were rubbed on stones to sharpen them, which also brought about tempering of martensite due to frictional heat.

  5. Surface grinding characteristics of ferrous metals under high-speed and speed-stroke grinding conditions

    International Nuclear Information System (INIS)

    Ghani, A.K.; Choudhury, I.A.; Ahim, M.B.

    1999-01-01

    Some ferrous metals have been ground under different conditions with high-speed and speed-stroke in surface grinding operation. The paper describes experimental investigation of grinding forces in grinding some ferrous metals with the application of cutting fluids. Grinding tests have been carried out on mild steel, assab steel and stainless steel with different combinations of down feed and cross feed. The wheel speed was 27 m/sec while the table speed was maintained at the maximum possible 25 m/min. The grindability has been evaluated by measuring the grinding forces, grinding ratio, and surface finish. Grinding forces have been plotted against down feed of the grinding wheel and cross feed of the table. It has been observed that the radial and tangential grinding forces in stainless steel were higher than those in assab steel and mild steel

  6. Bacteria-assisted preparation of nano α-Fe{sub 2}O{sub 3} red pigment powders from waste ferrous sulfate

    Energy Technology Data Exchange (ETDEWEB)

    Li, Xiang; Wang, Chuankai; Zeng, Yu; Li, Panyu; Xie, Tonghui; Zhang, Yongkui, E-mail: zhangyongkui@scu.edu.cn

    2016-11-05

    Highlights: • A route to prepare nano α-Fe{sub 2}O{sub 3} red pigment from waste ferrous sulfate is proposed. • Acidithiobacillus ferrooxidans is introduced for accelerating iron oxidation. • The particle size of synthetic α-Fe{sub 2}O{sub 3} is ranged from 22 nm to 86 nm. • The prepared nano α-Fe{sub 2}O{sub 3} red pigment fulfills ISO 1248-2006. - Abstract: Massive ferrous sulfate with excess sulfuric acid is produced in titanium dioxide industry each year, ending up stockpiled or in landfills as solid waste, which is hazardous to environment and in urgent demand to be recycled. In this study, waste ferrous sulfate was used as a second raw material to synthesize nano α-Fe{sub 2}O{sub 3} red pigment powders with a bacteria-assisted oxidation process by Acidithiobacillus ferrooxidans. The synthesis route, mainly consisting of bio-oxidation, precipitation and calcination, was investigated by means of titration, thermogravimetric analysis (TGA), X-ray diffraction (XRD), scanning electron microscope (SEM) and X-ray fluorescence (XRF) to obtain optimum conditions. Under the optimum conditions, nano α-Fe{sub 2}O{sub 3} red pigment powders contained 98.24 wt.% of Fe{sub 2}O{sub 3} were successfully prepared, with a morphology of spheroidal and particle size ranged from 22 nm to 86 nm and averaged at 45 nm. Moreover, the resulting product fulfilled ISO 1248-2006, the standards of iron oxide pigments.

  7. Conflitos ambientais: uma análise da assimetria de poder entre os atores sociais envolvidos no caso do Mineroduto da Ferrous / Environmental conflict: an analysis of power asymmetry between social actors involved in the case of Ferrous Pipeline

    Directory of Open Access Journals (Sweden)

    Dayane Rouse Neves Sousa

    2015-12-01

    Full Text Available This work intends to present the environmental conflict initiated due to the installation of pipeline Ferrous Ressources S / A, in the micro region of Viçosa-MG, building an analysis of the positioning of the main social actors involved, as well as their respective relations of power. Thepipeline of Ferrous will connect the complex Beam Mine in Congonhas-MG, the port of Ferrous Ressources in Presidente Kennedy-ES in order to export iron ore. To do so, were used as methodological procedures: bibliographical research; document analysis; semi-structured interviews with different actors; and follow-up meetings of the Popular Campaign Against the Water and Pipeline Ferrous, public hearings and demonstrations taken place in the Viçosa. Furthermore, there was monitoring of the pipeline discussion in local newspapers and on blogs. Thus, this study demonstrated that the Ferrous company, which owns high economic and symbolic power, assumes the role of dominating the conflict. On the other hand, those affected and social movements against the construction of the project, are sometimes in the role of dominated, leaving them to articulate strategies of resistance to delay / stop the construction of the pipeline. The state, in turn, assumes different roles in this context, demonstrating thereby weakness in mediation and conflict management established by pipeline Ferrous mainly in the micro region of Viçosa-MG.

  8. Synthesis and characterization of ferrous phosphate (vivianite) and its behavior in aqueous media

    International Nuclear Information System (INIS)

    Diaz F, J.C.

    2003-01-01

    The synthesis and characterization of materials that can be useful in Environmental Chemistry is very important because their characteristics are exposed and its behavior in chemical phenomena as the sorption in aqueous media is understand to use it in the human being benefit. With the object of using, in a future, the octa hydrated ferrous phosphate (vivianite) as a potential candidate for matrix confinement in contention walls for the storage of radioactive waste of long half life, it was synthesized and it characterized physico chemically and their properties of surface of this compound were evaluated. Presently work was carried out the synthesis and structural characterization of the iron phosphate II by infrared spectroscopy with having Fourier transform, high vacuum scanning electron microscopy, X-ray diffraction, thermal gravimetric analysis, the BET multipoint surface area and Moessbauer spectroscopy; as well as, the determination between aqueous media of the isoelectric point and the density of sites of surface of the compound. The octa hydrated ferrous phosphate was obtained pure. The results indicate that the product corresponds to the prospective mineral, the vivianite. The thermal gravimetric analysis demonstrated that the ferrous phosphate is a stable salt after the lost of water. The isoelectric point is since an important parameter because allows to know the behavior of the surface of the material in aqueous systems, in this case the isoelectric point, of the octa hydrated ferrous phosphate, in distilled water is of pH 4.20 and in solution of potassium nitrate 0.5 M is of pH = 3.75. This indicates that the material has an amphoteric surface depending on the pH. On the other hand, the density of active sites of surface obtained by titrations acid-base is of 20 sites by nm 2 . (Author)

  9. Dyeing Studies with Eucalyptus, Quercetin, Rutin, and Tannin: A Research on Effect of Ferrous Sulfate Mordant

    OpenAIRE

    Rattanaphol Mongkholrattanasit; Charoon Klaichoi; Nattadon Rungruangkitkrai; Nattaya Punrattanasin; Kamolkan Sriharuksa; Monthon Nakpathom

    2013-01-01

    Natural dyes from Eucalyptus leaf extract, quercetin, rutin, and tannin were applied to silk fabric by pad-batch and pad-dry techniques under different conditions. Ferrous sulfate was used as a mordant. The dyeing properties were evaluated by measuring K/S and CIELAB values. In addition, the different fastness properties were evaluated. The effect of dyes at different concentration levels with respect to their colour strength was also studied.

  10. [Severe toxic liver failure after acute poisoning with paracetamol, ferrous sulphate and naproxen].

    Science.gov (United States)

    Adamek, Robert; Wilczek, Lech; Krupiński, Bogusław

    2004-01-01

    We present the case of 20-year-old woman intoxicated with mixed drugs, composed of paracetamol (acetaminophen), ferrous sulphate, naproxen and benzodiazepines. Acute toxic liver damage with clinical symptoms of coma resolved at the patient. Lack of the past history doesn't let to specific therapy and systemic complications. In this data we confirm, that past history, clinical symptoms and laboratory results are needed in designing a treatment strategy.

  11. Determination of reliability of express forecasting evaluation of radiometric enriching ability of non-ferrous ores

    International Nuclear Information System (INIS)

    Kirpishchikov, S.P.

    1991-01-01

    Use of the data of nuclear physical methods of sampling and logging enables to improve reliability of evaluation of radiometric enriching ability of ores, as well as to evaluate quantitatively this reliability. This problem may be solved by using some concepts of geostatistics. The presented results enable to conclude, that the data of nuclear-physical methods of sampling and logging can provide high reliability of evaluation of radiometric enriching ability of non-ferrous ores and their geometrization by technological types

  12. Synthesis and characterization of a ferrous compound material obtained by combustion of ferroboron and ferrotitanium mixtures

    International Nuclear Information System (INIS)

    Bejar, M.A; Fuenzalida, J.L

    2008-01-01

    A ferrous compound material was synthesized in this work, by the air auto-combustion of mixtures of powdered ferroboron and ferrotitanium, compacted under pressures of 79 and 93 MPa and preheated to a temperature of about 1000 o C. The synthesized compounds were characterized by XRD analysis, and macro and micro-hardness tests. The formation of titanium diboride was found in all the synthesized test pieces (au)

  13. Stress corrosion cracking of several high strength ferrous and nickel alloys

    Science.gov (United States)

    Nelson, E. E.

    1971-01-01

    The stress corrosion cracking resistance of several high strength ferrous and nickel base alloys has been determined in a sodium chloride solution. Results indicate that under these test conditions Multiphase MP35N, Unitemp L605, Inconel 718, Carpenter 20Cb and 20Cb-3 are highly resistant to stress corrosion cracking. AISI 410 and 431 stainless steels, 18 Ni maraging steel (250 grade) and AISI 4130 steel are susceptible to stress corrosion cracking under some conditions.

  14. Sorption of ferrous iron by EPS from the acidophilic bacterium Acidiphilium Sp.: A mechanism proposal

    Energy Technology Data Exchange (ETDEWEB)

    Tapia, J.M.; MuNoz, J.; Gonzlez, F.; Blazquez, M.L.; Ballester, A.

    2016-07-01

    The aim of this work was to assess the uptake of Fe(II) by extracellular polymeric substances (EPS) from the acidophilic bacterium Acidiphillium 3.2Sup(5). These EPS were extracted using EDTA. EPS of A. 3.2Sup(5) loaded in sorption tests with Fe(II), were characterized using the following experimental techniques: scanning electron microscopy (SEM) with energy dispersive X-ray microanalysis (EDX), X-ray diffraction (XRD) and Fourier transform infrared spectroscopy (FTIR). The experimental results indicate that EPS adsorb ferrous iron according to Freundlich model with a metal sorption uptake of K = 1.14 mg1−1/n L1/n g−1 and a sorption intensity of 1/n = 1.26. In addition, ferrous iron sorption by EPS took place by preferential interaction with the carboxyl group which promotes the formation of ferrous iron oxalates (FeC2O4). Since the interaction reaction was reversible (Log K = 0.77 ± 0.33), that means that the cation sorption can be reversed at convenience. (Author)

  15. COMPARATIVE STUDY OF EFFICACY OF FERROUS SULPHATE AND CARBONYL IRON IN ANEMIA OF ANTENATAL WOMEN

    Directory of Open Access Journals (Sweden)

    Radhika

    2015-03-01

    Full Text Available Iron deficiency anemia is the most common and important public health problem all over the world in the risk group of antenatal women. Research is going on to improve the iron status of the pregnant women with different forms of iron available. In this regard, Carbonyl Iron is showing promising results in improving the red cell mass with better compliance. 120 antenatal women were recruited in this study. The study comprised of 6weeks for each patient. They were given Carbonyl Iron 100 mg/day and FeS04 100gm/day . Before and after treatment all the baseline and specific investigations were one. Results were tabulated, comparison and significance were tested by unpaired student ’s’ test and their 'p' value was calculated. Results were shown graphically also. Carbonyl Iron showed improvement in hemoglobin, PCV and better than ferrous Sulphate (P <0.001. Incidence of side effects were less with Carbonyl Iron than Ferrous Sulphate, better compliance was seen with Carbonyl Iron. In conclusion, the present study s howed that Carbonyl Iron had better efficacy and safety in the management of Iron deficiency anemia in antenatal women than ferrous Sulphate

  16. Oral iron therapy in human subjects, comparative absorption between ferrous salts and iron polymaltose

    International Nuclear Information System (INIS)

    Jacobs, P.; Johnson, G.; Wood, L.

    1984-01-01

    Iron absorption was directly compared between equivalent doses of ferrous salts and a polymaltose complex using a twin-isotope technique in which each individual acts as his own control. In the first study, bioavailability of iron from ferrous sulfate and the complex was defined at physiologic doses of 5 mg (Group 1: n = 14) and therapeutic doses of 50 mg (Group 2: n = 13). In Group 1, mean absorption from salt was 47.77% (SD 14.58%) and from polymaltose, 46.56% SD 17.07%). In Group 2, mean absorption from salt was 32.92% (SD 13.42%) and from polymaltose, 27.07% (SD 6.50%). In a second study, 100 mg of iron in a chewable formulation was used to compare absorption between equal doses of ferrous fumarate and the polymaltose complex. Mean absorption from salt was 10.25% (SD 6.89%) and from polymaltose 10.68% (SD 4.68%). At all three dosage levels, iron is equally available from salt or polymaltose for hemoglobin synthesis (p greater than 0.20), and absorption negatively correlated with plasma ferritin (p less than 0.01). These two materials may be used interchangeably in the treatment of patients with absolute iron deficiency

  17. Progress report of the Metallurgy Division for the period 1978-1980

    International Nuclear Information System (INIS)

    Sharma, B.D.; Mohan, Ashok; Bose, D.K.; Rao, C.N.; Chouthai, S.S.

    1980-01-01

    The research and development (R and D) work of the Metallurgy Division of the Bhabha Atomic Research Centre at Bombay for the period 1978-1980 is reported in the form of individual summaries under the headings: extractive metallurgy section, physical metallurgy section, corrosion and electrometallurgy section, ceramics section. Progress of work of beryllium pilot plant project, programme for R-5 utilisation for materials irradiation research project, development of rare, reactive and refractory metals, and development of ceramics materials for MHD programme is surveyed. Lists of publications, deputations, visits, conferences, colloquia are given. A chart at the end shows the various sections of the Division and personnel in each section. (M.G.B.)

  18. Plutonium metallurgy: The materials science challenges bridging condensed-matter physics and chemistry

    Energy Technology Data Exchange (ETDEWEB)

    Schwartz, A.J. [Lawrence Livermore National Laboratory, Livermore, CA 94550 (United States)], E-mail: schwartz6@llnl.gov

    2007-10-11

    Although there exists evidence of metallurgical practices dating back over 6000 years, studies of Pu and Pu alloys have been conducted for barely 60 years. During the time of the Manhattan Project and extending for some time afterward, the priority to produce the metal took precedence over the fundamental understanding of the metallurgical principals. In the past decade or so, there has been a resurgence in the basic metallurgy, condensed-matter physics, and chemistry of Pu and Pu alloys. These communities have made substantial progress, both experimentally and theoretically in many areas; however, many challenges still remain. The intent of this brief overview is to highlight a number important challenges that we face in the metallurgy of Pu including phase transformations and phase stability, aging, and the connection between electronic structure and metallurgy.

  19. Building of effluence and environment monitoring capability of uranium mining and metallurgy in China

    International Nuclear Information System (INIS)

    Li Xianjie; Hu Penghua; Duan Jianchen; Xue Jianxin

    2014-01-01

    The status of effluence and environmental monitoring capability of nine uranium mining and metallurgy corporations in operation in China was investigated and analyzed. The results show that there exist some problems in all corporations such as imperfect monitoring plan, ineligible analyst, aging equipment, insufficient analysis capacity, lack of good detection limit. In order to solve the problems, several steps have been taken by Department of Safety and Environment Protection and Department of Geology and Mining (CNNC) in three years, including establishing three-level monitoring sys- tem, equipping corresponding monitoring instrument, holding three training classes, enhancing the analyst capacity, publishing the model for effluence and environment monitoring capability of uranium mining and metallurgy and carrying out comparison on monitoring of U and Ra in water, which greatly improved effluence and environment monitoring capability of uranium mining and metallurgy. (authors)

  20. Microstructural characterisation of vacuum sintered T42 powder metallurgy high-speed steel after heat treatments

    International Nuclear Information System (INIS)

    Trabadelo, V.; Gimenez, S.; Iturriza, I.

    2009-01-01

    High-speed steel powders (T42 grade) have been uniaxially cold-pressed and vacuum sintered to full density. Subsequently, the material was heat treated following an austenitising + quenching + multitempering route or alternatively austenitising + isothermal annealing. The isothermal annealing route was designed in order to attain a hardness value of ∼50 Rockwell C (HRC) (adequate for structural applications) while the multitempering parameters were selected to obtain this value and also the maximum hardening of the material (∼66 HRC). Microstructural characterisation has been carried out by scanning electron microscopy (SEM) and transmission electron microscopy (TEM). The microstructure consists of a ferrous (martensitic or ferritic) matrix with a distribution of second phase particles corresponding to nanometric and submicrometric secondary carbides precipitated during heat treatment together with primary carbides. The identification of those secondary precipitates (mainly M 3 C, M 6 C and M 23 C 6 carbides) has allowed understanding the microstructural evolution of T42 high-speed steel under different processing conditions

  1. The Los Alamos National Laboratory Chemistry and Metallurgy Research Facility upgrades project - A model for waste minimization

    International Nuclear Information System (INIS)

    Burns, M.L.; Durrer, R.E.; Kennicott, M.A.

    1996-07-01

    The Los Alamos National Laboratory (LANL) Chemistry and Metallurgy Research (CMR) Facility, constructed in 1952, is currently undergoing a major, multi-year construction project. Many of the operations required under this project (i.e., design, demolition, decontamination, construction, and waste management) mimic the processes required of a large scale decontamination and decommissioning (D ampersand D) job and are identical to the requirements of any of several upgrades projects anticipated for LANL and other Department of Energy (DOE) sites. For these reasons the CMR Upgrades Project is seen as an ideal model facility - to test the application, and measure the success of - waste minimization techniques which could be brought to bear on any of the similar projects. The purpose of this paper will be to discuss the past, present, and anticipated waste minimization applications at the facility and will focus on the development and execution of the project's open-quotes Waste Minimization/Pollution Prevention Strategic Plan.close quotes

  2. The physical metallurgy of mechanically-alloyed, dispersion-strengthened Al-Li-Mg and Al-Li-Cu alloys

    Science.gov (United States)

    Gilman, P. S.

    1984-01-01

    Powder processing of Al-Li-Mg and Al-Li-Cu alloys by mechanical alloying (MA) is described, with a discussion of physical and mechanical properties of early experimental alloys of these compositions. The experimental samples were mechanically alloyed in a Szegvari attritor, extruded at 343 and 427 C, and some were solution-treated at 520 and 566 C and naturally, as well as artificially, aged at 170, 190, and 210 C for times of up to 1000 hours. All alloys exhibited maximum hardness after being aged at 170 C; lower hardness corresponds to the solution treatment at 566 C than to that at 520 C. A comparison with ingot metallurgy alloys of the same composition shows the MA material to be stronger and more ductile. It is also noted that properly aged MA alloys can develop a better combination of yield strength and notched toughness at lower alloying levels.

  3. Hydroxylamine-induced oxidation of ferrous carbonylated truncated hemoglobins from Mycobacterium tuberculosis and Campylobacter jejuni is limited by carbon monoxide dissociation.

    Science.gov (United States)

    Ascenzi, Paolo; Ciaccio, Chiara; Gasperi, Tecla; Pesce, Alessandra; Caporaso, Lucia; Coletta, Massimo

    2017-08-01

    Hydroxylamine (HA) is an oxidant of ferrous globins and its action has been reported to be inhibited by CO, even though this mechanism has not been clarified. Here, kinetics of the HA-mediated oxidation of ferrous carbonylated Mycobacterium tuberculosis truncated hemoglobin N and O (Mt-trHbN(II)-CO and Mt-trHbO(II)-CO, respectively) and Campylobacter jejuni truncated hemoglobin P (Cj-trHbP(II)-CO), at pH 7.2 and 20.0 °C, are reported. Mixing Mt-trHbN(II)-CO, Mt-trHbO(II)-CO, and Cj-trHbP(II)-CO solution with the HA solution brings about absorption spectral changes reflecting the disappearance of the ferrous carbonylated derivatives with the concomitant formation of the ferric species. HA oxidizes irreversibly Mt-trHbN(II)-CO, Mt-trHbO(II)-CO, and Cj-trHbP(II)-CO with the 1:2 stoichiometry. The dissociation of CO turns out to be the rate-limiting step for the oxidation of Mt-trHbN(II)-CO, Mt-trHbO(II)-CO, and Cj-trHbP(II)-CO by HA. Values of the second-order rate constant for HA-mediated oxidation of Mt-trHbN(II)-CO, Mt-trHbO(II)-CO, and Cj-trHbP(II)-CO range between 8.8 × 10 4 and 8.6 × 10 7 M -1 s -1 , reflecting different structural features of the heme distal pocket. This study (1) demonstrates that the inhibitory effect of CO is linked to the dissociation of this ligand, giving a functional basis to previous studies, (2) represents the first comparative investigation of the oxidation of ferrous carbonylated bacterial 2/2 globins belonging to the N, O, and P groups by HA, (3) casts light on the correlation between kinetics of HA-mediated oxidation and carbonylation of globins, and (4) focuses on structural determinants modulating the HA-induced oxidation process.

  4. Modernization of the Ural Metallurgy during the Great Patriotic War (1941–1945

    Directory of Open Access Journals (Sweden)

    Vladimir V. Zaparii

    2013-09-01

    Full Text Available The article characterizes the Ural industry modernization in war footing, shows the significance of evacuation of enterprises from the Western areas of the country to the region, reveals their role in the formation of a new metallurgical center of modern metallurgy in terms of human resources and manufacture. Innovations in metallurgy, the role of human factor in solving industrial restructuring problem are examined. Forms and methods of science use for the industrial modernization are considered. Solving of human resources problem is shown. The author touches upon the problem of metallurgical sector management in wartime. The role of people’s heroism in this difficult period of Russian history is discussed.

  5. Al/ B4C Composites with 5 and 10 wt% Reinforcement Content Prepared by Powder Metallurgy

    International Nuclear Information System (INIS)

    Yusof Abdullah; Mohd Reusmaazran Yusof; Azali Muhammad; Nadira Kamarudin; Wilfred Sylvester Paulus; Roslinda Shamsudin; Nasrat Hannah Shudin; Nurazila Mat Zali

    2012-01-01

    The preparation, physical and mechanical properties of Al/ B 4 C composites with 5 and 10 wt.% reinforcement content were investigated. In order to obtain the feedstock with a low powder loading, B 4 C mixtures containing fine powders were investigated to obtain the optimal particle packing. The experimental results indicated that the fine containing 5 and 10 wt.% particles are able to prepare the feedstock with a good flowability. The composites fabricated by powder metallurgy have low densities and homogeneous microstructures. Additionally there is no interface reaction observed between the reinforcement and matrix by XRD analysis. The hardness of Al/ B 4 C composites prepared by powder metallurgy was high. (Author)

  6. [Analysis of changes in characteristics of arterial hypertension occupational risk in workers of nonferrous metallurgy].

    Science.gov (United States)

    Vlasova, E M; Shliapnikov, D M; Lebedeva, T M

    2015-01-01

    The article covers changes in occupational cardiovascular risk for workers of nonferrous,metallurgy. Findings are that exposure to noise up to 94 dB with length of service increases possible atherosclerosis and metabolic syndrome. With 5 years of service, risk of the predicted conditions increases by 40.5%. When occupational exposure lasts over 5 years, risk of arterial hypertension increases. A group of workers without exposure to occupational factors appeared to have no connection between length of service and metabolic syndrome and arterial hypertension. Risk evolution modelling proved that risk of functional disorders in nonferrous metallurgy workers becomes unacceptable after 5 years of service (cardiovascular disorders are critical).

  7. Comprehensive waste characterization and organic pollution co-occurrence in a Hg and As mining and metallurgy brownfield

    Energy Technology Data Exchange (ETDEWEB)

    Gallego, J.R., E-mail: jgallego@uniovi.es [Environmental Technology, Biotechnology and Geochemistry Group, C/Gonzalo Gutiérrez Quirós s/n, 33600 Mieres, Asturias (Spain); Esquinas, N.; Rodríguez-Valdés, E.; Menéndez-Aguado, J.M. [Environmental Technology, Biotechnology and Geochemistry Group, C/Gonzalo Gutiérrez Quirós s/n, 33600 Mieres, Asturias (Spain); Sierra, C. [Environmental Technology, Biotechnology and Geochemistry Group, C/Gonzalo Gutiérrez Quirós s/n, 33600 Mieres, Asturias (Spain); Escuela Superior Politécnica del Litoral, Guayaquil (Ecuador)

    2015-12-30

    Highlights: • Complex legacy of contamination afflicts As–Hg brownfields. • As- and Hg-rich waste analyzed in a paradigmatic study site. • Co-ocurrence of a complex speciation of As and Hg, and organic pollution (PAHs). • Arsenolite was determined to be the main source of risk at the site. • Unexpected Hg organo-compounds found. - Abstract: The abandonment of Hg–As mining and metallurgy sites, together with long-term weathering, can dramatically degrade the environment. In this work it is exemplified the complex legacy of contamination that afflicts Hg–As brownfields through the detailed study of a paradigmatic site. Firstly, an in-depth study of the former industrial process was performed to identify sources of different types of waste. Subsequently, the composition and reactivity of As- and Hg-rich wastes (calcines, As-rich soot, stupp, and flue dust) was analyzed by means of multielemental analysis, mineralogical characterization (X-ray diffraction, electronic, and optical microscopy, microbrobe), chemical speciation, and sequential extractions. As-rich soot in the form of arsenolite, a relatively mobile by-product of the pyrometallurgical process, and stupp, a residue originated in the former condensing system, were determined to be the main risk at the site. In addition, the screening of organic pollution was also aimed, as shown by the outcome of benzo(a) pyrene and other PAHs, and by the identification of unexpected Hg organo-compounds (phenylmercury propionate). The approach followed unravels evidence from waste from the mining and metallurgy industry that may be present in other similar sites, and identifies unexpected contaminants overlooked by conventional analyses.

  8. Low temperature anaerobic bacterial diagenesis of ferrous monosulfide to pyrite

    Science.gov (United States)

    Donald, Ravin; Southam, Gordon

    1999-07-01

    In vitro enrichment cultures of dissimilatory sulfate-reducing bacteria precipitated FeS and catalyzed its transformation into FeS 2 at ambient temperature and pressure under anaerobic conditions. When compared to purely abiotic processes, the bacterially mediated transformation was shown to be more efficient in transforming FeS into FeS 2. This occurred due to the large, reactive surface area available for bacterially catalyzed diagenesis, where the biogenic FeS precursor was immobilized as a thin film (˜25 nm thick) on the μm-scale bacteria. The bacteria also contained the source(s) of sulfur for diagenesis to occur. Using a radiolabeled organic-sulfur tracer study, sulfur was released during cell autolysis and was immobilized at the bacterial cell surface forming FeS 2. The formation of FeS 2 occurred on both the inner and outer surfaces of the cell envelope and represented the first step of bacterial mineral diagenesis. Pyrite crystals, having linear dimensions of ˜1 μm, grew outward from the bacterial cell surfaces. These minerals were several orders of magnitude larger in volume than those originating abiotically.

  9. Reactivity of Uranium and Ferrous Iron with Natural Iron Oxyhydroxides.

    Science.gov (United States)

    Stewart, Brandy D; Cismasu, A Cristina; Williams, Kenneth H; Peyton, Brent M; Nico, Peter S

    2015-09-01

    Determining key reaction pathways involving uranium and iron oxyhydroxides under oxic and anoxic conditions is essential for understanding uranium mobility as well as other iron oxyhydroxide mediated processes, particularly near redox boundaries where redox conditions change rapidly in time and space. Here we examine the reactivity of a ferrihydrite-rich sediment from a surface seep adjacent to a redox boundary at the Rifle, Colorado field site. Iron(II)-sediment incubation experiments indicate that the natural ferrihydrite fraction of the sediment is not susceptible to reductive transformation under conditions that trigger significant mineralogical transformations of synthetic ferrihydrite. No measurable Fe(II)-promoted transformation was observed when the Rifle sediment was exposed to 30 mM Fe(II) for up to 2 weeks. Incubation of the Rifle sediment with 3 mM Fe(II) and 0.2 mM U(VI) for 15 days shows no measurable incorporation of U(VI) into the mineral structure or reduction of U(VI) to U(IV). Results indicate a significantly decreased reactivity of naturally occurring Fe oxyhydroxides as compared to synthetic minerals, likely due to the association of impurities (e.g., Si, organic matter), with implications for the mobility and bioavailability of uranium and other associated species in field environments.

  10. Elevated temperature crack growth in advanced powder metallurgy aluminum alloys

    Science.gov (United States)

    Porr, William C., Jr.; Gangloff, Richard P.

    1990-01-01

    Rapidly solidified Al-Fe-V-Si powder metallurgy alloy FVS0812 is among the most promising of the elevated temperature aluminum alloys developed in recent years. The ultra fine grain size and high volume fraction of thermally stable dispersoids enable the alloy to maintain tensile properties at elevated temperatures. In contrast, this alloy displays complex and potentially deleterious damage tolerant and time dependent fracture behavior that varies with temperature. J-Integral fracture mechanics were used to determine fracture toughness (K sub IC) and crack growth resistance (tearing modulus, T) of extruded FVS0812 as a function of temperature. The alloy exhibits high fracture properties at room temperature when tested in the LT orientation, due to extensive delamination of prior ribbon particle boundaries perpendicular to the crack front. Delamination results in a loss of through thickness constraint along the crack front, raising the critical stress intensity necessary for precrack initiation. The fracture toughness and tensile ductility of this alloy decrease with increasing temperature, with minima observed at 200 C. This behavior results from minima in the intrinsic toughness of the material, due to dynamic strain aging, and in the extent of prior particle boundary delaminations. At 200 C FVS0812 fails at K levels that are insufficient to cause through thickness delamination. As temperature increases beyond the minimum, strain aging is reduced and delamination returns. For the TL orientation, K (sub IC) decreased and T increased slightly with increasing temperature from 25 to 316 C. Fracture in the TL orientation is governed by prior particle boundary toughness; increased strain localization at these boundaries may result in lower toughness with increasing temperature. Preliminary results demonstrate a complex effect of loading rate on K (sub IC) and T at 175 C, and indicate that the combined effects of time dependent deformation, environment, and strain aging

  11. Investigation of the Environmental Durability of a Powder Metallurgy Material

    Science.gov (United States)

    Ward, LaNita D.

    2004-01-01

    PM304 is a NASA-developed composite powder metallurgy material that is being developed for high temperature applications such as bushings in high temperature industrial furnace conveyor systems. My goal this summer was to analyze and evaluate the effects that heat exposure had on the PM304 material at 500 C and 650 C. The material is composed of Ni-Cr, Ag, Cr2O3, and eutectic BaF2-CaF2. PM304 is designed to eliminate the need for oil based lubricants in high temperature applications, while reducing friction and wear. However, further investigation was needed to thoroughly examine the properties of PM304. The effects of heat exposure on PM304 bushings were investigated. This investigation was necessary due to the high temperatures that the material would be exposed to in a typical application. Each bushing was cut into eight sections. The specimens were heated to 500 C or 650 C for time intervals from 1 hr to 5,000 hrs. Control specimens were kept at room temperature. Weight and thickness measurements were taken before and after the bushing sections were exposed to heat. Then the heat treated specimens were mounted and polished side by side with the control specimens. This enabled optical examination of the material's microstructure using a metallograph. The specimens were also examined with a scanning electron microscope (SEM). The microstructures were compared to observe the effects of the heat exposure. Chemical analysis was done to investigate the interactions between Ni-Cr and BaF2-CaF2 and between Cr2O3 and BaF2-CaF2 at high temperature. To observe this, the two compounds that were being analyzed were mixed in a crucible in varied weight percentages and heated to 1100 C in a furnace for approximately two hours. Then the product was allowed to cool and was then analyzed by X-ray diffraction. Interpretation of the results is in progress.

  12. Metallurgy, environmental pollution and the decline of Etruscan civilisation.

    Science.gov (United States)

    Harrison, Adrian P; Cattani, Ilenia; Turfa, Jean M

    2010-01-01

    The Etruscans were justifiably famous in antiquity for their advanced metallurgy and for the rich mineral resources of their region (including La Tolfa, the Colline Metallifere, Mont'Amiata and Elba). We offer a new perspective on certain Iron Age and Archaic (ca. 1,000-480 BC: ) Etruscan industrial and habitation sites, and on the problem of heavy metal poisoning, still being investigated today, coincidentally in some of the same areas that originally saw Etruscan mines and workshops. This study investigates ancient sources, including literature and excavation reports, in the light of modern studies of heavy metal poisoning on human beings, plant and animal life. Furthermore, it is the first to use non-invasive Niton X-ray fluorescence analysis of samples of Etruscan (strictly ethnically Faliscan) hair (c. 350 BCE: ). The findings show the strong likelihood of heavy metal poisoning in areas of Etruscan metallurgical activity with the effects of this being responsible for or contributing to the abandonment of a number of these sites around the 6th century BC: . No thoroughly satisfactory explanation of this phenomenon has previously been offered. However, findings suggest that Faliscan women, represented by sample CG 2004-6-2, were not exposed to high levels of arsenic in life, which is not perhaps surprising for an urban aristocratic woman of the mid-4th century BC: . The reasons for the abandonment of several flourishing settlements are without doubt complex, and include political and social change. We suggest heavy metal contamination as an additional stimulus to the noted phenomenon of the peaceful abandonment, at the beginning, and at the end of the 6th century BC: , of sites in southern and northern Etruria such as Marsiliana d'Albegna (late 7th c.), Lago dell'Accesa, Acquarossa and Poggio Civitate-Murlo (late 6th c.). While the historical truth of the demise of Etruscan civilisation is much more complex, an interim set of related events, the desertion of

  13. Enhancing the electrochemical oxidation of acid-yellow 36 azo dye using boron-doped diamond electrodes by addition of ferrous ion

    International Nuclear Information System (INIS)

    Villanueva-Rodriguez, M.; Hernandez-Ramirez, A.; Peralta-Hernandez, J.M.; Bandala, Erick R.; Quiroz-Alfaro, Marco A.

    2009-01-01

    This work shows preliminary results on the electrochemical oxidation process (EOP) using boron-doped diamond (BDD) electrode for acidic yellow 36 oxidation, a common azo dye used in textile industry. The study is centred in the synergetic effect of ferrous ions and hydroxyl free radicals for improving discoloration of azo dye. The assays were carried out in a typical glass cell under potentiostatic conditions. On experimental conditions, the EOP was able to partially remove the dye from the reaction mixture. The reaction rate increased significantly by addition of Fe 2+ (1 mM as ferrous sulphate) to the system and by (assumed) generation of ferrate ion [Fe(VI)] over BDD electrode. Ferrate is considered as a highly oxidizing reagent capable of removing the colorant from the reaction mixture, in synergistic action with the hydroxyl radicals produced on the BDD surface. Further increases in the Fe 2+ concentration lead to depletion of the reaction rate probably due to the hydroxyl radical scavenging effect of Fe 2+ excess in the system.

  14. Corrosion behaviour of non-ferrous metals in sea water

    Energy Technology Data Exchange (ETDEWEB)

    Birn, Jerzy; Skalski, Igor [Ship Design and Research Centre, Al. Rzeczypospolitej 8, 80-369 Gdansk (Poland)

    2004-07-01

    The most typical kinds of corrosion of brasses are selective corrosion (dezincification) and stress corrosion. Prevention against these kinds of corrosion lies in application of arsenic alloy addition and appropriate heat treatment removing internal stresses as well as in maintaining the arsenic and phosphorus contents on a proper level. The most typical corrosion of cupronickels is the local corrosion. Selective corrosion occurs less often and corrosion cracking caused by stress corrosion in sea water does not usually occur. Crevice corrosion is found especially in places of an heterogeneous oxidation of the surface under inorganic deposits or under bio-film. Common corrosive phenomena for brasses and cupronickels are the effects caused by sea water flow and most often the impingement attack. Alloy additions improve resistance to the action of intensive sea water flow but situation in this field requires further improvement, especially if the cheaper kinds of alloys are concerned. Contaminants of sea water such as ammonia and hydrogen sulphide are also the cause of common corrosion processes for all copper alloys. Corrosion of copper alloys may be caused also by sulphate reducing bacteria (SRB). Galvanic corrosion caused by a contact with titanium alloys e.g. in plate heat exchangers may cause corrosion of both kinds copper alloys. Bronzes belong to copper alloys of the highest corrosion resistance. Failures that sometimes occur are caused most often by the cavitation erosion, by an incorrect chemical composition of alloys or at last by their inadequate structure. The main problems of aluminium alloys service in sea water are following phenomena: local corrosion (pitting and crevice corrosion), galvanic corrosion, exfoliation and corrosion in the presence of OH- ions. The cause of local corrosion are caused by presence of passive film on the alloy's surface and presence of chlorides in sea water which are able to damage the passive film. Galvanic corrosion is

  15. Ferrous archaeological analogues for the understanding of the multi-secular corrosion mechanisms in an anoxic environment

    International Nuclear Information System (INIS)

    Saheb-Djahromi, M.

    2009-12-01

    layer. From the obtained results, long term corrosion mechanisms in anoxic media have been proposed. One is based on the occurrence of a nano-metric non porous layer located at the metallic interface. The other one is based on a gel-like phase's formation. This study has enabled to propose new data on the corrosion processes occurring in anoxic media; these last must be integrated in the behaviour models of buried ferrous materials. (author)

  16. Recycling of wastes from uranium mining and metallurgy and recovery of useful resources in China

    International Nuclear Information System (INIS)

    Pan Yingjie; Xue Jianxin; Chen Zhongqiu

    2012-01-01

    Recycling of wastes from uranium mining and metallurgy in China and recovery of useful resources are summarized from the aspects such as recovery of uranium from mine water, reusing of waste water, decontaminating and recycling of radioactivity contaminated metal, backfill of gangues and tailings, and comprehensive recovery and utilization of associated uranium deposits. (authors)

  17. Metallurgy Department. Progress Report for the Period 1 January to 31 December 1984

    DEFF Research Database (Denmark)

    Risø National Laboratory, Roskilde

    The activities of the Metallurgy Department at Risø during 1984 are described. The work is presented in three chapters: General Materials Research, Technology and Materials Development, and Fuel Elements. A survey is given of the Department's participation in international collaboration and of its...

  18. Practical application of solid phase spectrophotometry in analysis of materials and goods of mining and metallurgy

    International Nuclear Information System (INIS)

    Duan Qunzhang

    1999-01-01

    The author reviewed recent development and practical application of solid phase spectrophotometry in analysis of materials and goods of mining-metallurgy. Separation and preconcentration and conditions of coloring determination, sensitivity and range of detection, as well as interference of corresponding method are discussed

  19. Ice-core evidence of earliest extensive copper metallurgy in the Andes 2700 years ago

    Science.gov (United States)

    Eichler, A.; Gramlich, G.; Kellerhals, T.; Tobler, L.; Rehren, Th.; Schwikowski, M.

    2017-01-01

    The importance of metallurgy for social and economic development is indisputable. Although copper (Cu) was essential for the wealth of pre- and post-colonial societies in the Andes, the onset of extensive Cu metallurgy in South America is still debated. Comprehensive archaeological findings point to first sophisticated Cu metallurgy during the Moche culture ~200-800 AD, whereas peat-bog records from southern South America suggest earliest pollution potentially from Cu smelting as far back as ~2000 BC. Here we present a 6500-years Cu emission history for the Andean Altiplano, based on ice-core records from Illimani glacier in Bolivia, providing the first complete history of large-scale Cu smelting activities in South America. We find earliest anthropogenic Cu pollution during the Early Horizon period ~700-50 BC, and attribute the onset of intensified Cu smelting in South America to the activities of the central Andean Chiripa and Chavin cultures ~2700 years ago. This study provides for the first time substantial evidence for extensive Cu metallurgy already during these early cultures.

  20. Mechanical properties of modified low cobalt powder metallurgy Udimet 700 type alloys

    Science.gov (United States)

    Harf, Fredric H.

    1989-01-01

    Eight superalloys derived from Udimet 700 were prepared by powder metallurgy, hot isostatically pressed, heat treated and their tensile and creep rupture properties determined. Several of these alloys displayed properties superior to those of Udimet 700 similarly prepared, in one case exceeding the creep rupture life tenfold. Filter clogging by extracted gamma prime, its measurement and significance are discussed in an appendix.

  1. 8th international congress on mining and metallurgy. 8. Congreso internacional de mineria y metalurgia

    Energy Technology Data Exchange (ETDEWEB)

    1988-01-01

    The meeting covered many aspects of mining and metallurgy including: underground and surface mining of coal; coal preparation; desulfurization and conversion; coal and coal waste combustion, including FBC; coal quality and chemistry; coal gasification; research programs on coal, the economics of the Spanish coal industry; and the Spanish coal industry and the European Community.

  2. Metallurgy Department progress report for the period 1 January to 31 December 1984

    International Nuclear Information System (INIS)

    1985-04-01

    The activities of the Metallurgy Department at Risoe during 1984 are described. The work is presented in three chapters: General Materials Research, Technology and Materials Development, and Fuel Elements. A survey is given of the Department's participation in international collaboration and of its activities within education and training. A list (with abstracts) of publications and lectures by the staff during 1984 is included. (author)

  3. Metallurgy department progress report for the period 1 January to 31 December 1982

    International Nuclear Information System (INIS)

    1983-07-01

    The activities of the Metallurgy Department at Risoe during 1982 are described. The work is presented in three chapters: General Materials Research, Technology and Materials Deveopment, Fuel Elements. Furthermore, a survey is given of the department's participation in international collaboration and of its activities within education and training. A list (with abstracts) of publications and lectures by the staff during 1982 is included. (author)

  4. Powder Metallurgy Preparation of Co-Based Alloys for Biomedical Applications

    Czech Academy of Sciences Publication Activity Database

    Marek, I.; Novák, P.; Mlynár, J.; Vojtěch, D.; Kubatík, Tomáš František; Málek, J.

    2015-01-01

    Roč. 128, č. 4 (2015), s. 597-601 ISSN 0587-4246. [International Symposium on Physics of Materials (ISPMA) /13./. Prague, 31.08.2014-04.09.2014] Institutional support: RVO:61389021 Keywords : powder metallurgy * mechanical properties * biomedical applications Subject RIV: JK - Corrosion ; Surface Treatment of Materials Impact factor: 0.525, year: 2015

  5. Application of powder metallurgy beryllium in Beijing spectrometer III beam pipe

    International Nuclear Information System (INIS)

    Zheng Lifang; Li Xunfeng; Wang Li; Ji Quan; Liu Jianping

    2008-01-01

    According to the requirements of Beijing Spectrometer III (BESIII) beam pipe, the physical properties of several materials were compared and powder metallurgy beryllium was chosen as the material for the central pipe of the BES III beam pipe. Weight-loss method was used to study the corrosion of powder metallurgy beryllium in No. 1 oil for electron discharge machining (EDM-1). The result shows that the anticorrosive property of powder metallurgy beryllium in EDM-1 is high. The corrosion rate, 4.18 x 10 -7 kg· m -2 ·h -1 in initial stage, becomes small with the lapse of the time and stabilizes at 1.54 x 10 -7 kg·m -2 ·h -1 at last. It can be estimated that the powder metallurgy beryllium will be corroded 19.9 μm in the depth in 10 years and it accounts for 3.32% of the smallest thickness of the central pipe, which satisfies the requirements of the BESIII. (authors)

  6. Power metallurgy approaches to high temperature components for gas turbine engines

    Science.gov (United States)

    Probst, H. B.

    1974-01-01

    Work conducted by NASA and NASA contractors on prealloyed superalloy powders and materials strengthened by oxide dispersion is reviewed. Fabrication, tensile strength, superplasticity, grain growth control, stress rupture life, and grain-size and dispersion-level effects are covered. Distinct strength advantages of powder metallurgy superalloys over conventional wrought alloys are noted.

  7. Ice-core evidence of earliest extensive copper metallurgy in the Andes 2700 years ago.

    Science.gov (United States)

    Eichler, A; Gramlich, G; Kellerhals, T; Tobler, L; Rehren, Th; Schwikowski, M

    2017-01-31

    The importance of metallurgy for social and economic development is indisputable. Although copper (Cu) was essential for the wealth of pre- and post-colonial societies in the Andes, the onset of extensive Cu metallurgy in South America is still debated. Comprehensive archaeological findings point to first sophisticated Cu metallurgy during the Moche culture ~200-800 AD, whereas peat-bog records from southern South America suggest earliest pollution potentially from Cu smelting as far back as ~2000 BC. Here we present a 6500-years Cu emission history for the Andean Altiplano, based on ice-core records from Illimani glacier in Bolivia, providing the first complete history of large-scale Cu smelting activities in South America. We find earliest anthropogenic Cu pollution during the Early Horizon period ~700-50 BC, and attribute the onset of intensified Cu smelting in South America to the activities of the central Andean Chiripa and Chavin cultures ~2700 years ago. This study provides for the first time substantial evidence for extensive Cu metallurgy already during these early cultures.

  8. [Concomitant influence of occupational and social risk factors on health of workers engaged into powder metallurgy].

    Science.gov (United States)

    Shur, P Z; Zaĭtseva, N V; Kostarev, V G; Lebedeva-Nesevria, N A; Shliapnikov, D M

    2012-01-01

    Results of health risk evaluation in workers engaged into powder metallurgy, using complex of hygienic, medical, epidemiologic and sociologic studies, enable to define priority occupational and social risk factors, to assess degree of their influence on the workers' health and to identify occupationally induced diseases.

  9. A Guide for Planning Facilities for Occupational Preparation Programs in Metallurgy Technology. Interim Report. Research 28.

    Science.gov (United States)

    German, Carl, Jr.

    The major purpose of this guide is to elicit the information necessary for writing educational specifications for facilities to house technical education programs in metallurgy. It is organized in these parts: (1) Part I discusses the major purpose, underlying assumptions, recent instructional trends, and guiding principles utilized in the…

  10. Powder metallurgy preparation of Al-Cu-Fe quasicrystals using mechanical alloying and Spark Plasma Sintering

    Czech Academy of Sciences Publication Activity Database

    Novák, P.; Kubatík, Tomáš František; Vystrčil, J.; Hendrych, R.; Kříž, J.; Mlynár, J.; Vojtěch, D.

    2014-01-01

    Roč. 52, September (2014), s. 131-137 ISSN 0966-9795 Institutional support: RVO:61389021 Keywords : Nanostructure intermetallics * Ternary alloys systems * Mechanical alloying and milling * Sintering * Diffraction Subject RIV: JG - Metallurgy Impact factor: 2.131, year: 2014 http://www.sciencedirect.com/science/article/pii/S0966979514001198#

  11. Metallurgy department progress report for the period 1 January to 31 December 1981

    International Nuclear Information System (INIS)

    1982-07-01

    The activities of the Metallurgy Department at Risoe during 1981 are described. The work is presented in three chapters: General Materials Research, Technology and Materials Development, Fuel Elements. Furthermore, a survey is given of the department's participation in international collaboration and of its activities within education and training. A list (with abstracts) of publications and lectures by the staff during 1981 is included. (author)

  12. Uranium mining and metallurgy library science and technology literature retrieval of network

    International Nuclear Information System (INIS)

    Tang Lilei

    2014-01-01

    This paper introduces the network resources and characteristics retrieve service of Beijing research Institute of Chemical Engineering of Metallurgy library, Analyzes the problems often encountered in the literature retrieval in science and technology, And puts forward the solution, Puts forward the thinking and Suggestions of science and technology literature retrieval. (author)

  13. Elucidating the role of ferrous ion cocatalyst in enhancing dilute acid pretreatment of lignocellulosic biomass

    Directory of Open Access Journals (Sweden)

    Wei Hui

    2011-11-01

    Full Text Available Abstract Background Recently developed iron cocatalyst enhancement of dilute acid pretreatment of biomass is a promising approach for enhancing sugar release from recalcitrant lignocellulosic biomass. However, very little is known about the underlying mechanisms of this enhancement. In the current study, our aim was to identify several essential factors that contribute to ferrous ion-enhanced efficiency during dilute acid pretreatment of biomass and to initiate the investigation of the mechanisms that result in this enhancement. Results During dilute acid and ferrous ion cocatalyst pretreatments, we observed concomitant increases in solubilized sugars in the hydrolysate and reducing sugars in the (insoluble biomass residues. We also observed enhancements in sugar release during subsequent enzymatic saccharification of iron cocatalyst-pretreated biomass. Fourier transform Raman spectroscopy showed that major peaks representing the C-O-C and C-H bonds in cellulose are significantly attenuated by iron cocatalyst pretreatment. Imaging using Prussian blue staining indicated that Fe2+ ions associate with both cellulose/xylan and lignin in untreated as well as dilute acid/Fe2+ ion-pretreated corn stover samples. Analyses by scanning electron microscopy and transmission electron microscopy revealed structural details of biomass after dilute acid/Fe2+ ion pretreatment, in which delamination and fibrillation of the cell wall were observed. Conclusions By using this multimodal approach, we have revealed that (1 acid-ferrous ion-assisted pretreatment increases solubilization and enzymatic digestion of both cellulose and xylan to monomers and (2 this pretreatment likely targets multiple chemistries in plant cell wall polymer networks, including those represented by the C-O-C and C-H bonds in cellulose.

  14. Study of Anti-Fatigue Effect in Rats of Ferrous Chelates Including Hairtail Protein Hydrolysates

    Directory of Open Access Journals (Sweden)

    Saibo Huang

    2015-12-01

    Full Text Available The ability of ferrous chelates including hairtail protein hydrolysates to prevent and reduce fatigue was studied in rats. After hydrolysis of hairtail surimi with papain, the hairtail protein hydrolysates (HPH were separated into three groups by range of relative molecular weight using ultrafiltration membrane separation. Hairtail proteins were then chelated with ferrous ions, and the antioxidant activity, the amino acid composition and chelation rate of the three kinds of ferrous chelates including hairtail protein hydrolysates (Fe-HPH were determined. Among the three groups, the Fe-HPH chelate showing the best conditions was selected for the anti-fatigue animal experiment. For it, experimental rats were randomly divided into seven groups. Group A was designated as the negative control group given distilled water. Group B, the positive control group, was given glutathione. Groups C, D and E were designated as the Fe-HPH chelate treatment groups and given low, medium, and high doses, respectively. Group F was designated as HPH hydrolysate treatment group, and Group G was designated as FeCl2 treatment group. The different diets were orally administered to rats for 20 days. After that time, rats were subjected to forced swimming training after 1 h of gavage. Rats given Fe-FPH chelate had higher haemoglobin regeneration efficiency (HRE, longer exhaustive swimming time and higher SOD activity. Additionally, Fe-FPH chelate was found to significantly decrease the malondialdehyde content, visibly enhance the GSH-Px activity in liver and reduce blood lactic acid of rats. Fe-HPH chelate revealed an anti-fatigue effect, similar to or better than the positive control substance and superior to HPH or Fe when provided alone.

  15. Protonation of Ferrous Dinitrogen Complexes Containing a Diphosphine Ligand with a Pendant Amine

    Energy Technology Data Exchange (ETDEWEB)

    Heiden, Zachariah M.; Chen, Shentan; Mock, Michael T.; Dougherty, William G.; Kassel, W. S.; Rousseau, Roger J.; Bullock, R. Morris

    2013-04-01

    The addition of protons to pendant amine containing ferrous dinitrogen complexes, of the type [FeX(N2)(PEtNMePEt)(dmpm)]+ (X = H, Cl, or Br; PEtNMePEt = Et2PCH2N(Me)CH2PEt2 and dmpm = Me2PCH2PMe2), was found to protonate at the pendant amine as opposed to the dinitrogen ligand. This protonation increased the νN2 of the complex by about 25 cm-1, shifting the Fe(II/I) couple 330 mV to a more positive potential. A similar shift was observed in the case of [FeX(CO)(PEtNMePEt)(dmpm)]+ (X = H, Cl, or Br). Computational analysis verified these experimental results and showed the coordination of N2 to Fe(II) centers increases the basicity of N2 (vs. free N2) by 13 and 20 pKa units for the trans halides and hydrides, respectively. Although the iron center was found to increase the basicity of the bound N2 ligand, coordinated N2 is not sufficiently basic to be protonated. In the case of ferrous dinitrogen complexes containing a basic pendant methylamine, the amine site was determined to be the most basic site by 30 pKa units compared to protonation at the N2 ligand. To increase the basicity of the N2 ligand in order to promote proton transfer from the pendant amine to the N2 ligand, chemical reduction of these ferrous dinitrogen complexes was performed and found to result in oxidative addition of the methylene C-H bond of the PEtNMePEt ligand to Fe, preventing isolation of a reduced Fe(0) N2 complex. This work was supported as part of the Center for Molecular Electrocatalysis, an Energy Frontier Research Center funded by the U.S. Department of Energy Office of Science, Office of Basic Energy Sciences.

  16. Effects of porosity on corrosion resistance of Mg alloy foam produced by powder metallurgy technology

    Energy Technology Data Exchange (ETDEWEB)

    Aghion, E., E-mail: egyon@bgu.ac.il; Perez, Y.

    2014-10-15

    Magnesium alloy foams have the potential to serve as structural material for regular light-weight applications as well as for biodegradable scaffold implants. However, their main disadvantage relates to the high reactivity of magnesium and consequently their natural tendency to corrode in regular service conditions and in physiological environments. The present study aims at evaluating the effect of porosity on the corrosion resistance of MRI 201S magnesium alloy foams in 0.9% NaCl solution and in phosphate buffer saline solution as a simulated physiological electrolyte. The magnesium foams were produced by powder metallurgy technology using space-holding particles to control the porosity content. Machined chips were used as raw material for the production of Mg alloy powder by milling process. The microstructure of the foams was examined using optical and scanning electron microscopy, X-ray diffraction, and X-ray photoelectron spectroscopy analysis. The corrosion behavior was evaluated by immersion test and potentiodynamic polarization analysis. The results obtained clearly demonstrate that the porosity has a significant effect on the corrosion resistance of the tested foams. Foams with 14–19% porosity have a corrosion rate of 4–10 mcd and 7–15 mcd in NaCl and phosphate buffer saline solution, respectively, compared to only 0.10 mcd for the same alloy in as cast conditions. This increased corrosion degradation of the Mg foams by more than one order of magnitude compared to the cast alloy may limit their potential application in regular and physiological environments. - Highlights: • Porosity has a detrimental effect on corrosion resistance of MRI 201S Mg foams. • 14–19% porosity increases the corrosion rate by more than one order of magnitude. • Accelerated corrosion limits the use of foams in regular/physiological environments.

  17. In vitro and in vivo biological performance of porous Ti alloys prepared by powder metallurgy.

    Science.gov (United States)

    do Prado, Renata Falchete; Esteves, Gabriela Campos; Santos, Evelyn Luzia De Souza; Bueno, Daiane Acácia Griti; Cairo, Carlos Alberto Alves; Vasconcellos, Luis Gustavo Oliveira De; Sagnori, Renata Silveira; Tessarin, Fernanda Bastos Pereira; Oliveira, Felipe Eduardo; Oliveira, Luciane Dias De; Villaça-Carvalho, Maria Fernanda Lima; Henriques, Vinicius André Rodrigues; Carvalho, Yasmin Rodarte; De Vasconcellos, Luana Marotta Reis

    2018-01-01

    Titanium (Ti) and Ti-6 Aluminium-4 Vanadium alloys are the most common materials in implants composition but β type alloys are promising biomaterials because they present better mechanical properties. Besides the composition of biomaterial, many factors influence the performance of the biomaterial. For example, porous surface may modify the functional cellular response and accelerate osseointegration. This paper presents in vitro and in vivo evaluations of powder metallurgy-processed porous samples composed by different titanium alloys and pure Ti, aiming to show their potential for biomedical applications. The porous surfaces samples were produced with different designs to in vitro and in vivo tests. Samples were characterized with scanning electron microscopy (SEM), energy dispersive spectroscopy (EDS) and elastic modulus analyses. Osteogenic cells from newborn rat calvaria were plated on discs of different materials: G1-commercially pure Ti group (CpTi); G2-Ti-6Al-4V alloy; G3-Ti-13 Niobium-13 Zirconium alloy; G4-Ti-35 Niobium alloy; G5-Ti-35 Niobium-7 Zirconium-5 Tantalum alloy. Cell adhesion and viability, total protein content, alkaline phosphatase activity, mineralization nodules and gene expression (alkaline phosphatase, Runx-2, osteocalcin and osteopontin) were assessed. After 2 and 4 weeks of implantation in rabbit tibia, bone ingrowth was analyzed using micro-computed tomography (μCT). EDS analysis confirmed the material production of each group. Metallographic and SEM analysis revealed interconnected pores, with mean pore size of 99,5μm and mean porosity of 42%, without significant difference among the groups (p>0.05). The elastic modulus values did not exhibit difference among the groups (p>0.05). Experimental alloys demonstrated better results than CpTi and Ti-6Al-4V, in gene expression and cytokines analysis, especially in early experimental periods. In conclusion, our data suggests that the experimental alloys can be used for biomedical

  18. Empirical analyses on the development trend of non-ferrous metal industry under China’s new normal

    Science.gov (United States)

    Li, C. X.; Liu, C. X.; Zhang, Q. L.

    2017-08-01

    The CGE model of Yunnan’s macro economy was constructed based on the input-output data of Yunnan in 2012, and the development trend of the non-ferrous metals industry (NMI) under the China’s new normal was simulated. In view of this, according to different expected economic growth, and optimized economic structure, the impact on development of Yunnan NMI was simulated. The results show that the NMI growth rate is expected to decline when the economic growth show a downward trend, but the change of the proportion is relatively small. Moreover, the structure in proportion was adjusted to realize the economic structure optimization, while the proportion of NMI in GDP will decline. In contrast, the biggest influence on the NMI is the change of economic structure. From the statistics of last two years, we can see that NMI is growing, and at the same time, its proportion is declining, which is consistent with the results of simulation. But the adjustment of economic structure will take a long time. It is need to improve the proportion of deep-processing industry, extend the industrial chain, enhance the value chain, so as to be made good use of resource advantage.

  19. Magnetic and Moessbauer-spectroscopic studies of iron-clusters in zeolites. [Reduction of ferrous ions

    Energy Technology Data Exchange (ETDEWEB)

    Schmidt, F; Gunsser, W; Knappwost, A [Hamburg Univ. (F.R. Germany). Inst. fuer Physikalische Chemie

    1975-12-01

    Iron clusters have been prepared within zeolite holes by reduction of zeolites containing ferrous ions. The diameter of these particles must therefore be smaller that 13 A. They are superparamagnetic and their Moessbauer spectra show no HFS, even at 4K. The temperature dependence of the magnetic susceptibility of the unreduced zeolites obeys a Curie-Weiss law with p/sub eff/ = 4.45 ..mu..B and THETA = 105K. The Weiss curves of the reduced samples lie distinctly below those of the bulk material.

  20. Friction and surface chemistry of some ferrous-base metallic glasses

    Science.gov (United States)

    Miyoshi, K.; Buckley, D. H.

    1982-01-01

    The friction properties of some ferrous-base metallic glasses were measured both in argon and in vacuum to a temperature of 350 C. The alloy surfaces were also analyzed with X-ray photoelectron spectroscopy to identify the compounds and elements present on the surface. The results of the investigation indicate that even when the surfaces of the amorphous alloys, or metallic glasses, are atomically clean, bulk contaminants such as boric oxide and silicon dioxide diffuse to the surfaces. Friction measurements in both argon and vacuum indicate that the alloys exhibit higher coefficients of friction in the crystalline state than they do in the amorphous state.