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Sample records for cast iron

  1. Special thermite cast irons

    OpenAIRE

    Yu. Zhiguts; I. Kurytnik

    2008-01-01

    The given paper deals with the problems of the synthesis of cast iron by metallothermy synthesis. On the basis of investigated method of calculations structures of charges have been arranged and cast iron has been synthesized further. Peculiarities metallothermic smelting were found, mechanical properties and structure of received cast iron were investigated and different technologies for cast iron receiving were worked out.

  2. Thin Wall Iron Castings

    Energy Technology Data Exchange (ETDEWEB)

    J.F. Cuttino; D.M. Stefanescu; T.S. Piwonka

    2001-10-31

    Results of an investigation made to develop methods of making iron castings having wall thicknesses as small as 2.5 mm in green sand molds are presented. It was found that thin wall ductile and compacted graphite iron castings can be made and have properties consistent with heavier castings. Green sand molding variables that affect casting dimensions were also identified.

  3. Special thermite cast irons

    Directory of Open Access Journals (Sweden)

    Yu. Zhiguts

    2008-07-01

    Full Text Available The given paper deals with the problems of the synthesis of cast iron by metallothermy synthesis. On the basis of investigated method of calculations structures of charges have been arranged and cast iron has been synthesized further. Peculiarities metallothermic smelting were found, mechanical properties and structure of received cast iron were investigated and different technologies for cast iron receiving were worked out.

  4. Nodular cast iron and casting monitoring

    Directory of Open Access Journals (Sweden)

    S. Pietrowski

    2008-10-01

    Full Text Available In this paper quality monitoring of nodular cast iron and casting made of it is presented. A control system of initial liquid cast iron to spheroidization, after spheroidization and inoculation with using of TDA method was shown. An application of an ultrasonic method to assessment of the graphite form and the metal matrix microstructure of castings was investigated.

  5. Colour Metallography of Cast Iron

    Institute of Scientific and Technical Information of China (English)

    Zhou Jiyang; Liu Jincheng

    2011-01-01

    White Cast Iron (Ⅰ) White cast iron or ‘white iron' refers to the type of cast iron in which all of the carbon exists as carbide;there is no graphite in the as-cast structure and the fractured surface shows a white colour.White cast iron can be divided in three classes:· Normal white cast iron — this iron contains only C,Si,Mn,P and S,with no other alloying elements.· Low-alloy white cast iron — the total mass fraction of alloying elements is less than 5%.

  6. Cast iron - a predictable material

    OpenAIRE

    Jorg C. Sturm; Guido Busch

    2011-01-01

    High strength compacted graphite iron (CGI) or alloyed cast iron components are substituting previously used non-ferrous castings in automotive power train applications. The mechanical engineering industry has recognized the value in substituting forged or welded structures with stiff and light-weight cast iron castings. New products such as wind turbines have opened new markets for an entire suite of highly reliable ductile iron cast components. During the last 20 years, casting process s...

  7. Colour Metallography of Cast Iron

    Institute of Scientific and Technical Information of China (English)

    Zhou Jiyang; Liu Jincheng

    2010-01-01

    @@ Chapter 3 Spheroidal Graphite Cast Iron(I) Spheroidal Graphite Cast Iron, SG iron in short, refers to the cast iron in which graphite precipitates as spheroidal shape during solidification of liquid iron. The graphite in common commercial cast iron can only be changed from flake to spheroidal shape by spheroidising treatment. Since spheroidal graphite reduces the cutting effect of stress concentration, the metal matrix strength of SG iron can be applied around 70%-90%, thus the mechanical property of SG iron is significantly superior to other cast irons;even the tensile strength of SG iron is higher than that carbon steel.

  8. Colour Metallography of Cast Iron

    Institute of Scientific and Technical Information of China (English)

    Zhou Jiyang; Ph.D Liu Jincheng

    2010-01-01

    @@ Note: This book consists of five sections: Chapter 1 Introduction, Chapter 2 Grey Iron, Chapter 3 Spheroidal Graphite Cast Iron, Chapter 4 Vermicular Cast Iron, and Chapter 5 White Cast Iron. CHINA FOUNDRY publishes this book in several parts serially, starting from the first issue of 2009.

  9. Colour Metallography of Cast Iron

    Institute of Scientific and Technical Information of China (English)

    Zhou Jiyang; Liu Jincheng

    2009-01-01

    @@ This book consists of five sections:Chapter 1 Introduction,Chapter 2 Grey Iron,Chapter 3 Ductile Iron,Chapter 4Vermicular Cast Iron,and Chapter 5 White Cast Iron. CHINA FOUNDRY publishs this book in several parts serially,starting from the first issue of 2009.

  10. Colour Metallography of Cast Iron

    Institute of Scientific and Technical Information of China (English)

    Zhou Jiyang; Liu Jincheng

    2011-01-01

    @@ Vermicular graphite cast iron(VG iron for short in the following sections)is a type of cast iron in which the graphite is intermediate in shape between flake and spheroidal.Compared with the normal flake graphite in grey iron, the graphite in VG iron is shorter and thicker and shows a curved, more rounded shape.Because its outer contour is exactly like a worm, hence it is called vermicular graphite.

  11. Colour Metallography of Cast Iron

    Institute of Scientific and Technical Information of China (English)

    Zhou Jiyang; Liu Jincheng

    2010-01-01

    @@ Spheroidal Graphite Cast Iron(Ⅳ) 3.7 Segregation of SG iron The non-uniform distribution of solute elements during solidification results in the micro segregation of SG iron.As for the redistribution of elements in the phases of the solidification structure,there is no intrinsic difference between SG iron and grey iron[132].

  12. Niobium in gray cast iron

    International Nuclear Information System (INIS)

    The potential for utilization of niobium in gray cast iron is appraised and reviewed. Experiments described in literature indicate that niobium provides structural refinement of the eutectic cells and also promotes pearlite formation. (Author)

  13. Colour Metallography of Cast Iron

    Institute of Scientific and Technical Information of China (English)

    Zhou Jiyang

    2009-01-01

    @@ Preface Cast iron, as a traditional metal material, has advantages of low total cost, good castability and machinability, good wear resistance and low notch sensitivity, and is still facing tough challenge in quality, property and variety of types etc.

  14. Bainite obtaining in cast iron with carbides castings

    Directory of Open Access Journals (Sweden)

    S. Pietrowski

    2010-01-01

    Full Text Available In these paper the possibility of upper and lower bainite obtaining in cast iron with carbides castings are presented. Conditions, when in cast iron with carbides castings during continuous free air cooling austenite transformation to upper bainite or its mixture with lower bainte proceeds, have been given. A mechanism of this transformation has been given, Si, Ni, Mn and Mo distribution in the eutectic cell has been tested and hardness of tested castings has been determined.

  15. Inoculation Effects of Cast Iron

    Directory of Open Access Journals (Sweden)

    E. Fraś

    2012-12-01

    Full Text Available The paper presents a solidification sequence of graphite eutectic cells of A and D types, as well as globular and cementite eutectics. The morphology of eutectic cells in cast iron, the equations for their growth and the distances between the graphite precipitations in A and D eutectic types were analyzed. It is observed a critical eutectic growth rate at which one type of eutectic transformed into another. A mathematical formula was derived that combined the maximum degree of undercooling, the cooling rate of cast iron, eutectic cell count and the eutectic growth rate. One type of eutectic structure turned smoothly into the other at a particular transition rate, transformation temperature and transformational eutectic cell count. Inoculation of cast iron increased the number of eutectic cells with flake graphite and the graphite nodule count in ductile iron, while reducing the undercooling. An increase in intensity of inoculation caused a smooth transition from a cementite eutectic structure to a mixture of cementite and D type eutectic structure, then to a mixture of D and A types of eutectics up to the presence of only the A type of eutectic structure. Moreover, the mechanism of inoculation of cast iron was studied.

  16. Cementite Solidification in Cast Iron

    Science.gov (United States)

    Coronado, J. J.; Sinatora, A.; Albertin, E.

    2014-06-01

    Two hypereutectic cast irons (5.01 pct Cr and 5.19 pct V) were cast and the polished surfaces of test pieces were deep-etched and analyzed via scanning electron microscopy. The results show that graphite lamellae intersect the cementite and a thin austenite film nucleates and grows on the cementite plates. For both compositions, graphite and cementite can coexist as equilibrium phases, with the former always nucleating and growing first. The eutectic carbides grow from the austenite dendrites in a direction perpendicular to the primary plates.

  17. Inoculation of chromium white cast iron

    Directory of Open Access Journals (Sweden)

    D. Kopyciński

    2009-01-01

    Full Text Available It has been proved that an addition of boron carbide introduced as an inoculant to the chromium white cast iron changes the structureof castings. Castings after inoculation revealed a different structure with numerous grains. Primary precipitates of chromium carbide also appeared, reducing the mechanical properties of as-cast parts. Properly established heat treatment regime makes chromium iron castings regain their, originally high, mechanical properties.

  18. Inoculation of chromium white cast iron

    OpenAIRE

    D. Kopyciński

    2009-01-01

    It has been proved that an addition of boron carbide introduced as an inoculant to the chromium white cast iron changes the structureof castings. Castings after inoculation revealed a different structure with numerous grains. Primary precipitates of chromium carbide also appeared, reducing the mechanical properties of as-cast parts. Properly established heat treatment regime makes chromium iron castings regain their, originally high, mechanical properties.

  19. Chilling Tendency and Chill of Cast Iron

    Institute of Scientific and Technical Information of China (English)

    E. Fra(s); M. Górny; W. Kapturkiewicz; H. López

    2008-01-01

    An analytical expression is presented for the susceptibility of liquid cast iron to solidify according tothe Fe-C-X metastable system (also known as the chilling tendency of cast iron, CT). The analysis incorpo-rates the nucleation and growth processes associated with the eutectic transformation. The CT is related tothe physicochemical state of the liquid, the eutectic cells in the flake graphite, and the number of nodules innodular cast iron. In particular, the CT can be related to the critical wall thickness, Scr, or the chill width, Wcr,in wedge shaped castings. Finally, this work serves as a guide for understanding the effect of technical fac-tors such as the melt chemistry, the spheroidizing and inoculation practice, and the holding time and tam-perature on the resultant CT and chill of the cast iron. Theoretical calculations of Scr and Wcr compare wellwith experimental data for flake graphite and nodular cast iron.

  20. Control of Cast Iron Microstructure

    Science.gov (United States)

    Graham, J.; Lillybeck, N.; Franco, N.; Stefanescu, D. M.

    1985-01-01

    The use of microgravity for industrial research in the processing of cast iron was investigated. Solidification experiments were conducted using the KC-135 and F-104 aircraft, and an experiment plan was developed for follow-on experiments using the Shuttle. Three areas of interest are identified: (1) measurement of thermophysical properties in the melt; (2) understanding of the relative roles of homogeneous nucleation, grain multiplication, and innocultants in forming the microstructure; and (3) exploring the possibility of obtaining an aligned graphite structure in hypereutectic Fe, Ni, and Co.

  1. WEAR-RESISTANCE OF CHROMIC CAST IRONS OF EUTECTIC COMPOSITION

    Directory of Open Access Journals (Sweden)

    K. E. Baranovskij

    2009-01-01

    Full Text Available Casting of wear-resistant chrome cast irons in combined molds and iron chills is studied. Application of these ways of casting results in blending of carbides and increasing of hardness of castings.

  2. 49 CFR 192.373 - Service lines: Cast iron and ductile iron.

    Science.gov (United States)

    2010-10-01

    ... 49 Transportation 3 2010-10-01 2010-10-01 false Service lines: Cast iron and ductile iron. 192.373... Regulators, and Service Lines § 192.373 Service lines: Cast iron and ductile iron. (a) Cast or ductile iron... cast iron pipe or ductile iron pipe is installed for use as a service line, the part of the...

  3. 49 CFR 192.275 - Cast iron pipe.

    Science.gov (United States)

    2010-10-01

    ... 49 Transportation 3 2010-10-01 2010-10-01 false Cast iron pipe. 192.275 Section 192.275... Cast iron pipe. (a) Each caulked bell and spigot joint in cast iron pipe must be sealed with mechanical leak clamps. (b) Each mechanical joint in cast iron pipe must have a gasket made of a...

  4. Thin Wall Ductile Iron Castings: Technological Aspects

    Directory of Open Access Journals (Sweden)

    E Fraś

    2013-01-01

    Full Text Available The paper discusses the reasons for the current trend of substituting ductile iron castings by aluminum alloys castings.However, it has been shown that ductile iron is superior to aluminum alloys in many applications. In particular it has beendemonstrated that is possible to produce thin wall wheel rim made of ductile iron without the development of chills, coldlaps or misruns. In addition it has been shown that thin wall wheel rim made of ductile iron can have the same weight, andbetter mechanical properties, than their substitutes made of aluminum alloys.

  5. Ductile iron castings fabricated using metallic moulds

    International Nuclear Information System (INIS)

    The features and suitability of high requirements ductile iron castings production using metallic moulds have been studied in the present work. The structural and mechanical properties of the produced castings have been analysed and compared to the corresponding ones but fabricated using green sand moulds according to a conventional production process. The higher cooling rate in the metallic moulds is the main cause for the appearance of the detected structural changes in castings. The mechanical and microstructural properties obtained directly on castings are remarkable due to the higher nodule count among other factors. Finally, the benefits and inconveniences found in this kind of production methodology using metallic moulds are also discussed. (Author)

  6. Colour Metallography of Cast Iron - Chapter 3: Spheroidal Graphite Cast Iron (Ⅰ

    Directory of Open Access Journals (Sweden)

    Zhou Jiyang

    2010-02-01

    Full Text Available Cast iron, as a traditional metal material, has advantages of low total cost, good castability and machinability, good wear resistance and low notch sensitivity, and is still facing tough challenge in quality, property and variety of types etc. Experts and engineers studying and producing iron castings all around world extremely concern this serious challenge. Over more than 30 years, a great of research work has been carried out on how to further improve its property, expand its application and combine cast iron technology with some hi-techs (for example, computer technology. Nevertheless, cast iron is a multi-element and multi-phase alloy and has complex and variety of structures and still has great development potential in structure and property. For further studying and developing cast iron, theoretical research work is important promise, and the study on solidification process and control mechanism of graphite morphology is fundamental for improving property of cast iron and developing new type of cast iron. Metallography of cast iron normally includes two sections: liquid phase transformation and solid phase transformation. The book, Colour Metallography of Cast Iron, uses colour metallography technique to study solidification structures of cast irons: graphite, carbides, austenite and eutectics; and focuses on solidification processes. With progress of modern solidification theory, the control of material solidification process becomes important measure for improving traditional materials and developing new materials. Solidification structure not only influences mechanical and physical properties of cast iron, but also affects its internal quality. The book uses a large amount of colour photos to describe the formation of solidification structures and their relations. Crystallization phenomena, which cannot be displayed with traditional metallography, are presented and more phase transformation information is obtained from these colour

  7. Colour Metallography of Cast Iron - Chapter 4: Vermicular Graphite Cast Iron (Ⅱ

    Directory of Open Access Journals (Sweden)

    Zhou Jiyang

    2011-05-01

    Full Text Available Cast iron, as a traditional metal material, has advantages of low total cost, good castability and machinability, good wear resistance and low notch sensitivity, and is still facing tough challenge in quality, property and variety of types etc. Experts and engineers studying and producing iron castings all around world extremely concern this serious challenge. Over more than 30 years, a great of research work has been carried out on how to further improve its property, expand its application and combine cast iron technology with some hi-techs (for example, computer technology. Nevertheless, cast iron is a multi-element and multi-phase alloy and has complex and variety of structures and still has great development potential in structure and property. For further studying and developing cast iron, theoretical research work is important promise, and the study on solidification process and control mechanism of graphite morphology is fundamental for improving property of cast iron and developing new type of cast iron. Metallography of cast iron normally includes two sections: liquid phase transformation and solid phase transformation. The book, Colour Metallography of Cast Iron, uses colour metallography technique to study solidification structures of cast irons: graphite, carbides, austenite and eutectics; and focuses on solidification processes. With progress of modern solidification theory, the control of material solidification process becomes important measure for improving traditional materials and developing new materials. Solidification structure not only influences mechanical and physical properties of cast iron, but also affects its internal quality. The book uses a large amount of colour photos to describe the formation of solidification structures and their relations. Crystallization phenomena, which cannot be displayed with traditional metallography, are presented and more phase transformation information is obtained from these colour

  8. Colour Metallography of Cast Iron - Chapter 3: Spheroidal Graphite Cast Iron (Ⅳ

    Directory of Open Access Journals (Sweden)

    Zhou Jiyang

    2010-11-01

    Full Text Available Cast iron, as a traditional metal material, has advantages of low total cost, good castability and machinability, good wear resistance and low notch sensitivity, and is still facing tough challenge in quality, property and variety of types etc. Experts and engineers studying and producing iron castings all around world extremely concern this serious challenge. Over more than 30 years, a great of research work has been carried out on how to further improve its property, expand its application and combine cast iron technology with some hi-techs (for example, computer technology. Nevertheless, cast iron is a multi-element and multi-phase alloy and has complex and variety of structures and still has great development potential in structure and property. For further studying and developing cast iron, theoretical research work is important promise, and the study on solidification process and control mechanism of graphite morphology is fundamental for improving property of cast iron and developing new type of cast iron. Metallography of cast iron normally includes two sections: liquid phase transformation and solid phase transformation. The book, Colour Metallography of Cast Iron, uses colour metallography technique to study solidification structures of cast irons: graphite, carbides, austenite and eutectics; and focuses on solidification processes. With progress of modern solidification theory, the control of material solidification process becomes important measure for improving traditional materials and developing new materials. Solidification structure not only influences mechanical and physical properties of cast iron, but also affects its internal quality. The book uses a large amount of colour photos to describe the formation of solidification structures and their relations. Crystallization phenomena, which cannot be displayed with traditional metallography, are presented and more phase transformation information is obtained from these colour

  9. Thin wall ductile and austempered iron castings

    Directory of Open Access Journals (Sweden)

    E. Fraś

    2010-07-01

    Full Text Available It has been shown that it is possible to produce thin wall castings made of ductile iron with wall thickness in the range of 1.2 to 2.9 mm(without chills, cold laps and misruns. Thin wall ductile iron castings can be lighter (380 g than their substitutes made of aluminium alloys (580g. The kinetics of austenitising transformation was studied in unalloyed ductile iron. The advance of transformations during austenitising was monitored by measurement the fraction of martensite and also by dilatometic studies. It has been shown that in thin wall ductile iron castings austenitising at 880 oC for 20 minutes is adequate to obtain the austenite matrix at the end of the first stage of austempering heat treatment cycle.

  10. DEVELOPMENTS IN THE FIELD OF STEEL AND CAST IRON

    OpenAIRE

    Ten, E. B.; V. D. Belov

    2015-01-01

    The article describes the use of a number of promising casting technologies applied to produce the castings of steel and cast iron with special properties. Such as, technology of centrifugal casting of large-size workpieces made of steel, forecasting method composition of slag in the smelting of high-manganese steels, method of complex modifying chromium cast irons, analysis of properties of perspective high-alloy aluminium cast iron.

  11. DEVELOPMENTS IN THE FIELD OF STEEL AND CAST IRON

    Directory of Open Access Journals (Sweden)

    E. B. Ten

    2015-05-01

    Full Text Available The article describes the use of a number of promising casting technologies applied to produce the castings of steel and cast iron with special properties. Such as, technology of centrifugal casting of large-size workpieces made of steel, forecasting method composition of slag in the smelting of high-manganese steels, method of complex modifying chromium cast irons, analysis of properties of perspective high-alloy aluminium cast iron.

  12. Spatial Bimetallic Castings Manufactured from Iron Alloys

    Directory of Open Access Journals (Sweden)

    M. Cholewa

    2007-07-01

    Full Text Available In this paper a conception for manufacturing method of skeleton castings with composite features was shown. Main application of such castings are the working organs of machines subjected to intensive abrasive and erosive wear. Skeleton geometry was based on three-dimensional cubic net consisting of circular connectors and nodes joining 6 connectors according to Cartesian co-ordinate system. Dimension of an elementary cell was equal to 10 mm and diameter of single connector was equal to 5 mm. For bimetallic castings preparation two Fe based alloys were used: L25SHMN cast steel for skeleton substrate and ZlCr15NiMo cast iron for working part of the casting. In presented work obtained structure was analyzed with indication of characteristic regions. Authors described phenomena occurring at the alloys interface and phases in transition zone. A thesis was formulated concerning localization of transition zone at the cast iron matrix – cast steel reinforcement interface. Direction of further studies were indicated.

  13. Colour Metallography of Cast Iron

    Institute of Scientific and Technical Information of China (English)

    Zhou Jiyang

    2009-01-01

    @@ Grey Iron(Ⅲ) 2.5 Crystallization of the LTF during final stage of eutectic solidification of grey iron In the final stage of eutectic solidification, eutectic cells grow gradually into large sizes; the liquid iron between the cells enters the last stage of solidification. At this time, the region of the remaining liquid iron is called last to freeze volume, LTF in short, as shown in Fig.2-39.

  14. Dynamic fracture behavior of nodular cast iron

    International Nuclear Information System (INIS)

    Ferritic nodular cast iron has been found to be a much tougher material than previously believed based on Charpy impact test results. As a result this material is being considered as a substitute for Stainless Steel in nuclear waste transport containers. We have determined Klc and Kld values for nodular cast iron with varying values of silicon and percentage of pearlite in the matrix. Regular V-notch charpy bars and fatigue precracked charpy bars have been tested to determine the initiation and propagation energy and the effect of notch acuity on transition temperature. (author)

  15. Recent development of ductile cast iron production technology in China

    Directory of Open Access Journals (Sweden)

    Cai Qizhou

    2008-05-01

    Full Text Available Recent progress in the production and technology of ductile cast iron castings in China is reviewed. The manufacture and process control of as-cast ductile iron are discussed. The microstructure, properties and application of partial austenitization normalizing ductile iron and austempered ductile iron (ADI are briefl y depicted. The new development of ductile iron production techniques, such as cored-wire injection (wire-feeding nodularization process, tundish cover ladle nodularizing process, horizontal continuous casting, and EPC process (lost foam for ductile iron castings, etc., are summarized.

  16. Recent development of ductile cast iron production technology in China

    Institute of Scientific and Technical Information of China (English)

    Cai Qizhou; Wei Bokang

    2008-01-01

    Recent progress in the production and technology of ductile cast iron castings in China is reviewed.The manufacture and process control of as-cast ductile iron are discussed.The microstructure.properties and application of partial austenitization normalizing ductile iron and austempered duclile iron(ADI)are briefly depicted.The new development of duclile iron production techniques,such as cored-wire injection(wire-feeding nodularization)process,tundish cover ladle nodularizing process,horizontal continuous casting,and EPC process (lost foam)for ductile iron castings,etc.,are summarized.

  17. 46 CFR 153.239 - Use of cast iron.

    Science.gov (United States)

    2010-10-01

    ... 46 Shipping 5 2010-10-01 2010-10-01 false Use of cast iron. 153.239 Section 153.239 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) CERTAIN BULK DANGEROUS CARGOES SHIPS CARRYING BULK... Systems § 153.239 Use of cast iron. (a) Cast iron used in a cargo containment system must meet...

  18. Manufacturing of thin walled near net shape iron castings

    DEFF Research Database (Denmark)

    Larsen, Per Leif

    2003-01-01

    substituting iron casings with aluminum castings. Substituting iron castings with aluminum castings is not as easy as first believed, and hence the substitution is very slow. This combined with the lack of fully exploiting the potential in iron castings, makes research in iron castings interesting. The 60......The demand for near net shape thin walled iron castings is growing. This has several reasons, the main one is the need for lowering the fuel consumption of cars; the easiest way to do that is to lower the weight of the cars. The best way to do this was for a period of time believed to be.......000.000 cars produced world wide each year consumes enormous amounts of cast parts ! The aim of the project is to develop the green sand molding method on DISAMATIC to be able to deal with the new demands for thin walled near net shape castings in iron....

  19. Control of the metallurgical processing of ICDP cast irons

    OpenAIRE

    Hampl, Jiří; Válek, Tomáš; Lichý, Petr; Elbel, Tomáš

    2014-01-01

    The article is focused on the use of the measurement of oxygen activity for the management of cast-iron metallurgical processing in the operating conditions of a centrifugal-roll casting foundry. The paper presents the results of the oxygen-activity measurement recorded during the metallurgical processing of cast iron from the beginning of the melting to the inoculation of cast iron. The measurement of oxygen activity was made with specifically developed devices and the probes with a...

  20. Graphitization in chromium cast iron

    OpenAIRE

    LECOMTE-BECKERS, Jacqueline; Terziev, L.; Breyer, J. P.

    1998-01-01

    Some trials with graphite Hi-Cr iron rolls have been done mainly in Japan, for the rolling of stainless steel. This material could lead to good compromise between oxidation, wear and thermal behaviour. By using thermal analysis and resistometry, the conditions for secondary graphite formation have been studied. The amount and volume of free graphite may be strongly increased by a suitable heat treatment, allowing a good thermal conductivity as well as high wear and mechanical properties.

  1. Studies of the transition zone in steel – chromium cast iron bimetallic casting

    Directory of Open Access Journals (Sweden)

    S. Tenerowicz

    2010-01-01

    Full Text Available In this work authors presented the results of transition zone studies on steel – cast iron interface in bimetallic casting. During the investigations cylindrical castings with different diameter were prepared of cast iron with steel rods placed in the center. From each bimetallic casting a microsection was prepared for microhardness tests and metalographic analysis, consisting of transition zone measurement, point and linear analysis as well as quantitative analysis.

  2. Maintenance system improvement in cast iron foundry

    Directory of Open Access Journals (Sweden)

    S. Kukla

    2011-07-01

    Full Text Available The work presents the issue of technical equipment management in an iron foundry basing on the assumptions of the TPM system (Total Productive Maintenance. Exploitation analysis of automatic casting lines has been carried out and their work’s influence on the whole production system’s functioning has been researched. Within maintenance system improvement, implementation of autonomic service and planned lines’ review have been proposed in order to minimize the time of breakdown stoppages. The SMED method was used to optimize changeover time, and the OEE (Overall Equipment Effectiveness was applied to evaluate the level of resources usage before and after implementing changes. Further, the influence of the maintenance strategy of casting devices’ efficiency on own costs of casting manufac- ture was estimated.

  3. Inoculated Slightly Hypereutectic Gray Cast Irons

    Science.gov (United States)

    Chisamera, Mihai; Riposan, Iulian; Stan, Stelian; Militaru, Cristina; Anton, Irina; Barstow, Michael

    2012-03-01

    The current experimental investigation in this article was designed to characterize the structure of mold (M) and ladle (L) inoculated, low-S (0.025 wt.% S), low-Al (0.003 wt.% Al), slightly hypereutectic (CE = 4.4-4.5 wt.%) electric melted gray irons, typical for high performance thin-wall castings. It describes the effect of a Ca, Al, Zr-FeSi inoculant addition of 0-0.25 wt.% on structure characteristics, and compares to similar treatments with hypoeutectic irons (3.5-3.6 wt.% CE, 0.025 wt.% S, and 0.003 wt.% Al). A complex structure including primary graphite, austenite dendrites, and eutectic cells is obtained in hypereutectic irons, as the result of nonequilibrium solidification following the concept of a coexisting region. Dendrites appear to be distributed between eutectic cells at higher eutectic undercooling, while in inoculated irons and for lower undercooling, the eutectic cells are "reinforced" by eutectic austenite dendrites. A Zr, Ca, Al-FeSi alloy appears to be an effective inoculant in low S, low Al, gray cast irons, especially for a late inoculation technique, with beneficial effects on both graphite and austenite phases. First, inoculation influenced the nucleation of graphite/eutectic cell, and then their characteristics. A further role of these active elements directly contributed to form nucleation sites for austenite, as complex (Mn,X)S particles.

  4. Thin Wall Cast Iron: Phase II

    Energy Technology Data Exchange (ETDEWEB)

    Doru M. Stefanescu

    2005-07-21

    The development of thin-wall technology allows the designers of energy consuming equipment to select the most appropriate material based on cost/material properties considerations, and not solely on density. The technology developed in this research project will permit the designers working for the automotive industry to make a better informed choice between competing materials and thin wall cast iron, thus decreasing the overall cost of the automobile.

  5. Crystallization of nodular cast iron with carbides

    Directory of Open Access Journals (Sweden)

    S. Pietrowski

    2008-12-01

    Full Text Available In this paper a crystallization process of nodular cast iron with carbides having a different chemical composition have been presented. It have been found, that an increase of molybdenum above 0,30% causes the ledeburutic carbides crystallization after (γ+ graphite eutectic phase crystallization. When Mo content is lower, these carbides crystallize as a pre-eutectic phase. In this article causes of this effect have been given.

  6. Maintenance system improvement in cast iron foundry

    OpenAIRE

    S. Kukla

    2011-01-01

    The work presents the issue of technical equipment management in an iron foundry basing on the assumptions of the TPM system (Total Productive Maintenance). Exploitation analysis of automatic casting lines has been carried out and their work’s influence on the whole production system’s functioning has been researched. Within maintenance system improvement, implementation of autonomic service and planned lines’ review have been proposed in order to minimize the time of breakdown stoppages. The...

  7. The temperature gradient on section of casting in process of primary crystallization of chromium cast iron

    Directory of Open Access Journals (Sweden)

    A. Studnicki

    2008-08-01

    Full Text Available The methodology of defining in article was introduced the temperature gradient in process of primary crystallization during cooling the casting from chromium cast iron on basis of measurements of thermal field in test DTA-K3. Insert also the preliminary results of investigations of influence temperature gradient on structure of studied wear resistance chromium cast iron.

  8. Eutectic solidification mode of spheroidal graphite cast iron and graphitization

    OpenAIRE

    Hideo Nakae; Sanghoon Jung; Takayuki Kitazawa

    2007-01-01

    The shrinkage and chilling tendency of spheroidal graphite (abbreviated SG) cast iron is much greater than that of the flake graphite cast iron in spite of its higher amount of C and Si contents. Why? The main reason should be the difference in their graphitization during the eutectic solidification. In this paper, we discuss the difference in the solidification mechanism of both cast irons for solving these problems using unidirectional solidification and the cooling curves of the spheroidal...

  9. RESEARCH AND APPLICATION OF AS-CAST WEAR RESISTANCE HIGH CHROMIUM CAST IRON

    Institute of Scientific and Technical Information of China (English)

    1998-01-01

    The influence of alloy elements, such as boron and silicon, on the microstructure and properties of as-cast high chromium cast iron is studied. The results show that boron and silicon have a great effect on the mechanical properties and the wear resistance. Through proper addition of boron and silicon, the properties of as-cast high chromium cast iron can be improved effectively. Through analyzing the distribution of elements by scanning electron microscope, it has been shown that the addition of boron and silicon lowers the mass fraction of chromium saturated in as-cast austenite, and makes it unstable and liable to be transformed into martensite. The as-cast high chromium cast iron with proper content of boron and silicon is suitable for the manufacture of lining for asphalt concrete mixer and its wear resistance is 14 times that of lining made of low alloy white cast iron.

  10. Costs Analysis of Iron Casts Manufacturing

    Directory of Open Access Journals (Sweden)

    S. Kukla

    2012-04-01

    Full Text Available The article presents the issues of costs analysis of iron casts manufacturing using automated foundry lines. Particular attention was paid to departmental costs, conversion costs and costs of in-plant transport. After the Pareto analysis had been carried out, it was possible to set the model area of the process and focus on improving activities related to finishing of a chosen group of casts. In order to eliminate losses, the activities realised in this domain were divided into activities with added value, activities with partially added value and activities without added value. To streamline the production flow, it was proposed to change the location of workstations related to grinding, control and machining of casts. Within the process of constant improvement of manufacturing processes, the aspect of work ergonomics at a workstation was taken into account. As a result of the undertaken actions, some activities without added value were eliminated, efficiency was increased and prime costs of manufacturing casts with regard to finishing treatment were lowered.

  11. Solidification of cast iron - A study on the effect of microalloy elements on cast iron

    DEFF Research Database (Denmark)

    Moumeni, Elham

    of the austenite, in the last region to solidify. The superfine graphite which forms in this type of irons is short (10-20µm) and stubby. The microstructure of this kind of graphite flakes in titanium alloyed cast iron is studied using electron microscopy techniques. The methods to prepare samples of...... the unetched, colour-etched and deep-etched samples. It was confirmed that in irons with high sulphur content (0.12 wt%) nucleation of type-A and type-D graphite occurs on Mn sulphides that have a core of complex Al, Ca, Mg oxide. An increased titanium level of 0.35% produced superfine interdendritic...

  12. Colour Metallography of Cast Iron Chapter 2 Introduction (Ⅰ)

    Institute of Scientific and Technical Information of China (English)

    Zhou Jiyang; Liu Jincheng

    2009-01-01

    @@ Grey iron is type of cast iron with grey color fracture and carbon precipitated as flake graphite.According to its chemical compostion in Fe-C phase diagram,grey iron is categorised into three types:hypoeutectic,eutecitic,hypereutecitic irons are hypoeutecic compostion.

  13. Colour Metallography of Cast Iron - Chapter 1: Introduction (Ⅰ

    Directory of Open Access Journals (Sweden)

    Zhou Jiyang

    2009-02-01

    Full Text Available Cast iron, as a traditional metal material, has advantages of low total cost, good castability and machinability, good wear resistance and low notch sensitivity, and is still facing tough challenge in quality, property and variety of types etc. Experts and engineers studying and producing iron castings all around world extremely concern this serious challenge. Over more than 30 years, a great of research work has been carried out on how to further improve its property, expand its application and combine cast iron technology with some hi-techs (for example, computer technology. Nevertheless, cast iron is a multi-element and multi-phase alloy and has complex and variety of structures and still has great development potential in structure and property. For further studying and developing cast iron, theoretical research work is important promise, and the study on solidification process and control mechanism of graphite morphology is fundamental for improving property of cast iron and developing new type of cast iron. Metallography of cast iron normally includes two sections: liquid phase transformation and solid phase transformation. The book, Colour Metallography of Cast Iron, uses colour metallography technique to study solidification structures of cast irons: graphite, carbides, austenite and eutectics; and focuses on solidification processes. With progress of modern solidification theory, the control of material solidification process becomes important measure for improving traditional materials and developing new materials. Solidification structure not only influences mechanical and physical properties of cast iron, but also affects its internal quality. The book uses a large amount of colour photos to describe the formation of solidification structures and their relations. Crystallization phenomena, which cannot be displayed with traditional metallography, are presented and more phase transformation information is obtained from these colour

  14. Eutectic solidification mode of spheroidal graphite cast iron and graphitization

    Directory of Open Access Journals (Sweden)

    Hideo Nakae

    2007-02-01

    Full Text Available The shrinkage and chilling tendency of spheroidal graphite (abbreviated SG cast iron is much greater than that of the flake graphite cast iron in spite of its higher amount of C and Si contents. Why? The main reason should be the difference in their graphitization during the eutectic solidification. In this paper, we discuss the difference in the solidification mechanism of both cast irons for solving these problems using unidirectional solidification and the cooling curves of the spheroidal graphite cast iron. The eutectic solidification rate of the SG cast iron is controlled by the diffusion of carbon through the austenite shell, and the final thickness is 1.4 times the radius of the SG, therefore, the reduction of the SG size, namely, the increase in the number, is the main solution of these problems.

  15. Spall behavior of cast iron with varying microstructures

    International Nuclear Information System (INIS)

    The spall strength of cast iron with varying microstructures has been investigated using plate impact at moderate speed. Stress history measurements were made with manganin stress gauges embedded between the back face of the specimen and a low impedance polycarbonate backing. Five separate cast irons were tested. Four of these consisted of gray cast iron with graphite in flake form, with three classified as Type VII A2 and the fourth containing a bimodal distribution of Types VII A4 and VII D8. The fifth casting consisted of ductile cast iron with graphite in nodular form, classified as Type I, size class 5. The spall strength for the Type VII A2 gray cast irons varied between 40 and 370 MPa, and that of the additional gray cast iron, between 410 and 490 MPa. The spall strength of the ductile cast iron fell within the range of 0.94–1.2 GPa. It is shown that the spall strength is linked to the damage level at the spall plane, where an increased level of tensile stress is required to generate higher levels of damage. Post mortem analysis was performed on the recovered samples, revealing the graphite phase to be the primary factor governing the spall fracture of cast irons, where crack nucleation is directly correlated to the debonding of graphite from the metal matrix. The average length of graphite found within a casting is linked to the material's strength, where strength increases as a function of decreasing length. The morphology and mean free path of graphite precipitates further govern the subsequent coalescence of initiated cracks to form a complete fracture plane. In cases where graphite spacing is large, increased energy level is required to complete the fracture process. A secondary factor governing the spall fracture of cast irons has also been linked to the microstructure of the metal matrix, with pearlite yielding higher spall strengths than free ferrite.

  16. Wear resistance of chromium cast iron – research and application

    Directory of Open Access Journals (Sweden)

    A. Studnicki

    2006-04-01

    Full Text Available Purpose: A short characteristic of wear resistance chromium cast iron has been presented as well as possibilities of this material researches realization in Foundry Department have been discussed.Design/methodology/approach: Main attention was given on research process of crystallization and analysis of chromium cast iron microstructure and its resistance on erosion wears. Separate part of paper was devoted to discuss the bimetallic castings with chromium cast iron layer as well as typical applications of chromium cast iron castings in minig, proccesing, metallurgical and power industry.Findings: The new method of crystallization process research with three testers (DTA-K3 was found in the work. The method makes possible to characterize sensitivity of chromium cast iron on cooling kinetic.Research limitations/implications: DTA-K3 method can be used for research of crystallization proccess of cast materials particularly for abrasion-resisting alloy.Practical implications: Wide scope researches of chromium cast iron in Foundry Department enable extending applications its material in many industries.Originality/value: Value of the paper is the presentation of researches possibilities which undertaken in Foundry Department within the range of wear resistant materials.

  17. Laboratory grey cast iron continuous casting line with electromagnetic forced convection support

    Directory of Open Access Journals (Sweden)

    J. Szajnar

    2010-07-01

    Full Text Available The article describes the construction of a 20 mm diameter grey cast iron ingots continuous casting laboratory line. This line is made ofthree main units: melting unit (induction furnace, casting unit and the pulling unit. In order to improve the homogeneity of themicrostructure of ingots (by applying forced convection of liquid metal during the crystallization process in this case a crystallizer system generating the forced movement of liquid metal based on a system of electrical power windings of the AC specific frequency. Thissolution allowed to obtain a homogeneous microstructure of the continuous casting of cast iron EN-GJL-200 species.

  18. Tribological Aspects of Cast Iron Investigated Via Fracture Toughness

    OpenAIRE

    C. Fragassa; Minak, G; A. Pavlovic

    2016-01-01

    Linear-elastic plane-strain fracture toughness of metallic materials is a method which covers the determination of the strain fracture toughness (KIC) of metallic materials by increasing-force test of fatigue precracked specimens. This method has been applied for investigating the fracture behaviour of cast iron. Two groups of cast alloys, Compacted Graphite Iron (CGI) and Spheroidal Graphite Iron (SGI) have been investigated. While SGI benefits of a wide scientific literature, CGI is a relat...

  19. Acoustic energy transmission in cast iron pipelines

    Science.gov (United States)

    Kiziroglou, Michail E.; Boyle, David E.; Wright, Steven W.; Yeatman, Eric M.

    2015-12-01

    In this paper we propose acoustic power transfer as a method for the remote powering of pipeline sensor nodes. A theoretical framework of acoustic power propagation in the ceramic transducers and the metal structures is drawn, based on the Mason equivalent circuit. The effect of mounting on the electrical response of piezoelectric transducers is studied experimentally. Using two identical transducer structures, power transmission of 0.33 mW through a 1 m long, 118 mm diameter cast iron pipe, with 8 mm wall thickness is demonstrated, at 1 V received voltage amplitude. A near-linear relationship between input and output voltage is observed. These results show that it is possible to deliver significant power to sensor nodes through acoustic waves in solid structures. The proposed method may enable the implementation of acoustic - powered wireless sensor nodes for structural and operation monitoring of pipeline infrastructure.

  20. Fracture analysis of chilled cast iron camshaft

    Institute of Scientific and Technical Information of China (English)

    Li Ping; Li Fengjun; Cai Anke; Wei Bokang

    2009-01-01

    The fracture of a camshaft made of chilled cast iron, installed in a home-made Fukang car, happened only after running over a distance of 6,200 km. The fractured camshaft was received to conduct a series of failure analyses using visual inspection, SEM observation of fracture section, microstructure analysis, chemical composition analysis and hardness examination and so on, while those of CKD camshaft made by Citroen Company in France was also simultaneously analyzed to compare the difference between them. The results showed that the fracture of the camshaft mainly results from white section in macrostructure and Ledeburite in microstructure; the crack in the fractured camshaft should be recognized to initiate at the boundary of coarser needle-like carbide and matrix, and then propagate through the transverse section. At the same time, the casting defects such as dendritic shrinkage, accumulated inclusion and initiated crack and abnormal external force might stimulate the fracture of camshaft as well. Based on failure analysis, some measures have been employed, and as a result, the fracture of home-made camshafts has been effectively prevented.

  1. 49 CFR 192.369 - Service lines: Connections to cast iron or ductile iron mains.

    Science.gov (United States)

    2010-10-01

    ... 49 Transportation 3 2010-10-01 2010-10-01 false Service lines: Connections to cast iron or ductile iron mains. 192.369 Section 192.369 Transportation Other Regulations Relating to Transportation... Customer Meters, Service Regulators, and Service Lines § 192.369 Service lines: Connections to cast iron...

  2. Optimization of the Chemical Composition of Cast Iron Used for Casting Ball Bearing Grinding Disks

    Institute of Scientific and Technical Information of China (English)

    Aurel Crisan; Sorin Ion; Munteanu; Ioan Ciobanu; Iulian Riposan

    2008-01-01

    The chemical composition of cast iron used for casting ball bearing machining disks was varied to optimize the properties such as castability, hardenability, and durability in ball machining. The cast iron characteristics were most strongly dependent on the Ni content and the carbon saturation degree, So. This paper describes the types of test specimens, the working conditions, and the experimental results. The in-crease of the degree of carbon saturation reduces the tendency to form shrinkholes in the castings. The de-crease in the Ni content negatively affects the final hardening treatment. A way to control solidification de-fects in cast iron, by reducing the Ni content, has been verified on cast disks.

  3. Interaction between alloying and hardening of cast iron surface

    Institute of Scientific and Technical Information of China (English)

    刘政军; 郝雪枫; 傅迎庆; 牟力军

    2002-01-01

    To improve wear resistance of surface will increase the service life of gray cast iron directly. This paper presents that gray cast iron surface coated with alloy powder is locally remelted by TIG arc to increase the wear resistance. The influences of arc current and scanning rate etc on surface properties are found. Under different conditions, the microstructure, hardness and wear resistance of remelted layer are analyzed and measured. The results indicate that the gray cast iron surface can be strengthened by TIG arc local remelting treatment. Especially, surface alloying hardening effect is best and surface properties are improved remarkably.

  4. CASTING OF DETAILS OF WEAR-RESISTANT CHROME CAST IRONS FOR CHROMIC MILLS IN COMBINED MOLDS AND CHILLS

    Directory of Open Access Journals (Sweden)

    K. E. Baranovskij

    2009-01-01

    Full Text Available Relative wear resistance of chrome cast irons of eutectic composition is determined in laboratory and industry conditions. Complex alloyed eutectic cast iron with increased wear resistance and mechanical characteristics is developed.

  5. The surface layer of austempered ductile iron investment castings properties

    Directory of Open Access Journals (Sweden)

    D. Myszka

    2009-01-01

    Full Text Available The article presents a unique process of carbonnitriding and nitriding the precision casting surfaces of austempered ductile iron. The results of the research are pointing that adequate process parameters allow to obtain multiple increase of wear resistance and a significant increase of corrosion resistance. Also, changes of cast microstructure and hardness are presented.

  6. The structure of high-quality aluminium cast iron

    Directory of Open Access Journals (Sweden)

    D. Kopyciński

    2012-01-01

    Full Text Available In this study presents the analyse of aluminium iron cast structure (as-cast condition which are used in high temperature. While producing the casts of aluminium iron major influence has been preserve the structure of technological process parameters. The addition to Fe-C-Al alloy V, Ti, Cr leads to the improvement of functional and mechanical cast qualities. In this study, a method was investigated to eliminate the presence of undesirable Al4C3 phases in a aluminium cast iron structure and thus improve the production process. V and Ti additions in aluminium cast iron allows to development of FeAl - VC or TiC alloys. In particular, V or Ti contents above 5 wt.% were found to totally eliminate the presence of Al4C3. In addition, preliminary work indicates that the alloy with the FeAl - VC or TiC structure reveals high oxidation resistance. The introduction of 5 wt.% chromium to aluminium cast iron strengthened Al4C3 precipitate. Thus, the resultant alloy can be considered an intermetallic FeAl matrix strengthened by VC and TiC or modified Al4C3 reinforcements.

  7. Analysis of the structure of castings made from chromium white cast iron resistant to abrasive wear

    Directory of Open Access Journals (Sweden)

    D. Kopyciński

    2009-10-01

    Full Text Available It has been proved that an addition of boron carbide and disintegrated steel scrap introduced as an inoculant to the chromium white cast iron changes the structure of castings. The said operation increases the number of crystallization nuclei for dendrites of the primary austenite. In this case, the iron particles act as substrates for the nucleation of primary austenite due to a similar crystallographic lattice. The more numerous are the dendrites of primary austenite and the structure more refined and the mechanical properties higher. Castings after B4C inoculation revealed a different structure of fine grained fracture. Primary precipitates of chromium carbide also appeared, reducing the mechanical properties of as-cast parts. Properly established heat treatment regime makes chromium iron castings regain their, originally high, mechanical properties.

  8. Surface hardening of two cast irons by friction stir processing

    International Nuclear Information System (INIS)

    The Friction Stir Processing (FSP) was applied to the surface hardening of cast irons. Flake graphite cast iron (FC300) and nodular graphite cast iron (FCD700) were used to investigate the validity of this method. The matrices of the FC300 and FC700 cast irons are pearlite. The rotary tool is a 25mm diameter cylindrical tool, and the travelling speed was varied between 50 and 150mm/min in order to control the heat input at the constant rotation speed of 900rpm. As a result, it has been clarified that a Vickers hardness of about 700HV is obtained for both cast irons. It is considered that a very fine martensite structure is formed because the FSP generates the heat very locally, and a very high cooling rate is constantly obtained. When a tool without an umbo (probe) is used, the domain in which graphite is crushed and striated is minimized. This leads to obtaining a much harder sample. The hardness change depends on the size of the martensite, which can be controlled by the process conditions, such as the tool traveling speed and the load. Based on these results, it was clarified that the FSP has many advantages for cast irons, such as a higher hardness and lower distortion. As a result, no post surface heat treatment and no post machining are required to obtain the required hardness, while these processes are generally required when using the traditional methods.

  9. Structure and mechanical properties of vermicular cast iron in cylinder head casting

    OpenAIRE

    Guzik, E.; S. Dzik

    2009-01-01

    The paper discusses the problem of grain density and ferrite content in microstructure of vermicular graphite iron cast in bars of different section diameters and cylinder head casting. The experimental results regarding the section effect demonstrate that the nodule count, grain density and ferrite content are all function of the cast bar diameter in this particular case ranging from 0.6 to 8.0 cm and microstructure and mechanical properties in the cylinder head. The nodule count (or grain d...

  10. The change of temperature gradient in solidification of hypereutectic chromium cast iron casting

    OpenAIRE

    A. Studnicki

    2010-01-01

    In article the analysis of temperature gradient of solidification in section of hypereutectic chromium cast iron model casting was introduced. On this example was presented the method (DTGA – derivative and thermal gradient analysis), which was worked out in Department of Foundry Silesian University of Technology enabling the record of indispensable data to execution of analysis the temperature gradient and its derivative after time on section of model casting. It multichanneled apparatus to ...

  11. The change of temperature gradient in solidification of hypereutectic chromium cast iron casting

    Directory of Open Access Journals (Sweden)

    A. Studnicki

    2010-01-01

    Full Text Available In article the analysis of temperature gradient of solidification in section of hypereutectic chromium cast iron model casting was introduced. On this example was presented the method (DTGA – derivative and thermal gradient analysis, which was worked out in Department of Foundry Silesian University of Technology enabling the record of indispensable data to execution of analysis the temperature gradient and its derivative after time on section of model casting. It multichanneled apparatus to registration of data was used Crystaldigraph - PC.

  12. Stereological parameters of carbides on section of casting made from modified chromium cast iron

    Directory of Open Access Journals (Sweden)

    A. Studnicki

    2011-07-01

    Full Text Available The analysis of stereological parameters of carbides on the section of the model castingmade from modified (the mixture FeNb+FeV+RE wear resistance chromium cast iron was introduced in the article. The jump change of some stereological parameters of carbides in certain distance from the surface of the casting was observed.

  13. FORMATION OF WEAR-RESISTANT CHROMIUM CAST IRON CASTING INTO THE CHILL MOLD

    Directory of Open Access Journals (Sweden)

    E. I. Marukovich

    2015-05-01

    Full Text Available The analysis of thermal processes of formation of castings from wearproof chromic cast irons for replaceable details of centrifugal mills and crushers is carried out. Influence of protective and dividing coverings on intensity of heating of the chill mold is investigated.

  14. FORMATION OF WEAR-RESISTANT CHROMIUM CAST IRON CASTING INTO THE CHILL MOLD

    OpenAIRE

    E. I. Marukovich; V. M. Ilyushenko; P. Yu. Duvalov

    2015-01-01

    The analysis of thermal processes of formation of castings from wearproof chromic cast irons for replaceable details of centrifugal mills and crushers is carried out. Influence of protective and dividing coverings on intensity of heating of the chill mold is investigated.

  15. Residual stresses in a cast iron automotive brake disc rotor

    International Nuclear Information System (INIS)

    Runout, and consequent juddering and pulsation through the brake pedal, is a multi-million dollar per year warranty problem for car manufacturers. There is some suspicion that the runout can be caused by relaxation of residual casting stresses when the disc is overheated during severe-braking episodes. We report here neutron-diffraction measurements of the levels and distribution of residual strains in a used cast iron brake disc rotor. The difficulties of measuring stresses in grey cast iron are outlined and three-dimensional residual-strain distributions are presented and their possible effects discussed

  16. EFFICIENCY CHARACTERISTICS OF MICROALLOYED AND MODIFIED WHITE CAST IRONS

    Directory of Open Access Journals (Sweden)

    M. M. Jamshinskiy

    2015-05-01

    Full Text Available Influencing of chrome and manganese in the wide range of their concentrations on wear proof of white cast-irons for making of the poured details working in the conditions of intensive abrasive and hydroabrasive wear is studied. It is set that at optimum correlation of these elements cast-irons have high hardness, wearproof and satisfactory casting properties, allowing to make the poured details of different mass, geometry and overall sizes. Influence of processes of микролегирования and modification is explored on operating properties of the recommended Cr-Mn cast-iron 290Х19Г4 and expedience of the use of these processes is set at production of the wearproof foundings taking into account concrete external environments.

  17. Bainitic nodular cast iron with carbides obtaining with use of Inmold method

    Directory of Open Access Journals (Sweden)

    G. Gumienny

    2009-07-01

    Full Text Available In these paper bainitic nodular cast iron with carbides as-cast obtaining has been presented. This cast iron has been obtained with use of Inmold method. It was shown, that there is the possibility of bainite and carbides obtaining in cast iron with Mo and Ni for studied chemical composition.

  18. The influence of cooling rate on the hardness of cast iron with nodular and vermicular graphite

    OpenAIRE

    M.S. Soiński; B. Zatoń; A. Skoczylas; A. Derda

    2008-01-01

    The paper presents hardness changes for cast iron with nodular and vermicular graphite, determined within the separately cast test blocks. Investigation has comprised cast irons with similar ferrite and pearlite fractions in the metal matrix. The hardness measurements have been performed by Brinell method for samples taken both from an edge and from the centre of a Y block (for nodular cast iron) or of a reversed U block (in the case of vermicular cast iron). Investigations have pertained bot...

  19. 46 CFR 56.60-10 - Cast iron and malleable iron.

    Science.gov (United States)

    2010-10-01

    ... and malleable iron fittings conforming to the specifications of 46 CFR 56.60-1, Table 56.60-1(a) may...; see 46 CFR 56.01-2) and if their service does not exceed the rating as marked on the valve. (b) Cast... 46 Shipping 2 2010-10-01 2010-10-01 false Cast iron and malleable iron. 56.60-10 Section...

  20. Abrasion Resistance of as-Cast High-Chromium Cast Iron

    Directory of Open Access Journals (Sweden)

    Pokusová Marcela

    2014-12-01

    Full Text Available High chromium cast irons are widely used as abrasion resistant materials. Their properties and wear resistance depend on carbides and on the nature of the matrix supporting these carbides. The paper presents test results of irons which contain (in wt.% 18-22 Cr and 2-5 C, and is alloyed by 1.7 Mo + 5 Ni + 2 Mn to improve the toughness. Tests showed as-cast irons with mostly austenitic matrix achieved hardness 36-53 HRC but their relative abrasion-resistance was higher than the tool steel STN 19436 heat treated on hardness 60 HRC.

  1. Formation of microstructures in the spheroidal graphite cast iron

    International Nuclear Information System (INIS)

    Pipeline systems for hydraulic networks are obtained via centrifugal casting of spheroidal graphite cast iron. The very high cooling rate that is achieved in the skin of the product can sometimes lead to carbide instead of graphite in cast iron. An experimental device has been built in the laboratory that allows reproducing the extreme thermal conditions encountered during formation of skin of centrifugally cast pipes. Liquid metal droplets fall on a cold substrate. Rapid directional solidification occurs. The temperature evolution of the lower surface of the droplet is recorded during the very first moment of the solidification (t < 200 ms) thanks to a photodiode, which is located below the substrate. The microstructures that are obtained in laboratory are characterised in both the as-cast state and the heat-treated state. They are compared to the centrifugally cast ones. A model of directional solidification of cast iron under a very large temperature gradient has been built. It allows explaining the transition from stable to metastable micro structure that was observed in the products and reproduced in the laboratory samples.

  2. Control of microstructure of cast irons Indefinite Chill Double Pour-ICDP

    Directory of Open Access Journals (Sweden)

    T.Válek

    2011-10-01

    Full Text Available ICDP cast irons designated for working layer of centrifugal cylinders of rolling mill must have precisely defined properties. The most closely observed parameters of the ICDP (Indefinite Child Double Pour cast irons are the following: the amount of graphite in a microstructure and hardness of base metal material. Secretion of graphite in cast iron with ledeburitic basic metal compound is a complex process that can be controlled and managed with the use of thermal analysis. On the basis of the evaluation of cooling curve parameters of cast iron there is performed metallurgical adjustment of meltage by adding elements supporting graphite end carbide formation into cast iron. The identified structural and mechanical properties of ICDP cast irons were correlated with recorded KO. Subsequently, a methodology for control of the metallurgical adjustment of cast iron before casting was proposed so as to ensure the desired microstructure and properties the ICDP cast iron.

  3. Computer-aided control of high-quality cast iron

    Directory of Open Access Journals (Sweden)

    S. Pietrowski

    2008-04-01

    Full Text Available The study discusses the possibility of control of the high-quality grey cast iron and ductile iron using the author’s genuine computer programs. The programs have been developed with the help of algorithms based on statistical relationships that are said to exist between the characteristic parameters of DTA curves and properties, like Rp0,2, Rm, A5 and HB. It has been proved that the spheroidisation and inoculation treatment of cast iron changes in an important way the characteristic parameters of DTA curves, thus enabling a control of these operations as regards their correctness and effectiveness, along with the related changes in microstructure and mechanical properties of cast iron. Moreover, some examples of statistical relationships existing between the typical properties of ductile iron and its control process were given for cases of the melts consistent and inconsistent with the adopted technology.A test stand for control of the high-quality cast iron and respective melts has been schematically depicted.

  4. Stereology of carbide phase in modified hypereutectic chromium cast iron

    Directory of Open Access Journals (Sweden)

    J. Suchoń

    2010-04-01

    Full Text Available In paper are presented results of studies of carbide phase stereology modified hypereutectic wear resistance chromium cast iron which contains carbon about 3,5% and chromium about 25%. Three substances were applied to the modification: boron carbide (B4C, ferroniobium (FeNb and mixture of ferroniobium and rare-earth (RE. The measurements of geometrical features of carbides were conducted on microsection taken from castings wich were cooled with various velocities.

  5. Stereology of carbide phase in modified hypereutectic chromium cast iron

    OpenAIRE

    J. Suchoń; A. Studnicki; M. Przybył

    2010-01-01

    In paper are presented results of studies of carbide phase stereology modified hypereutectic wear resistance chromium cast iron which contains carbon about 3,5% and chromium about 25%. Three substances were applied to the modification: boron carbide (B4C), ferroniobium (FeNb) and mixture of ferroniobium and rare-earth (RE). The measurements of geometrical features of carbides were conducted on microsection taken from castings wich were cooled with various velocities.

  6. Thermodynamic stability of austenitic Ni-Mn-Cu cast iron

    Directory of Open Access Journals (Sweden)

    A. Janus

    2014-07-01

    Full Text Available The performed research was aimed at determining thermodynamic stability of structures of Ni-Mn-Cu cast iron castings. Examined were 35 alloys. The castings were tempered at 900 °C for 2 hours. Two cooling speeds were used: furnace-cooling and water-cooling. In the alloys with the nickel equivalent value less than 20,0 %, partial transition of austenite to martensite took place. The austenite decomposition ratio and the related growth of hardness was higher for smaller nickel equivalent value and was clearly larger in annealed castings than in hardened ones. Obtaining thermodynamically stable structure of castings requires larger than 20,0 % value of the nickel equivalent.

  7. Carbides in Nodular Cast Iron with Cr and Mo

    Directory of Open Access Journals (Sweden)

    S. Pietrowski

    2007-07-01

    Full Text Available In these paper results of elements microsegregation in carbidic nodular cast iron have been presented. A cooling rate in the centre of the cross-section and on the surface of casting and change of moulding sand temperature during casting crystallization and its self-cooling have been investigated. TDA curves have been registered. The linear distribution of elements concentration in an eutectic grain, primary and secondary carbides have been made. It was found, that there are two kinds of carbides: Cr and Mo enriched. A probable composition of primary and secondary carbides have been presented.

  8. Casting Ductile Iron in Layer Moulds Made from Ecological Sands

    OpenAIRE

    M. Rączka; K. Gandurski; B. Isendorf

    2012-01-01

    The article contains the results of tests performed under the target project in Hardtop Foundry Charsznica.The objective of the tests and studies was to develop a technology of making high-quality ductile iron castings, combined witheffective means of environmental protection. The studies presented in this article related to castings weighing from 1 to 300 kg made from ductile iron of grades 400-15 and 500-7, using two-layer moulds, where the facing and core sand was the sand with an alkaline...

  9. Thin wall ductile iron casting as a substitute for aluminum alloy casting in automotive industry

    Directory of Open Access Journals (Sweden)

    M. Górny

    2009-01-01

    Full Text Available In paper it is presented thin wall ductile iron casting (TWDI as a substitute of aluminium alloy casting. Upper control arm made of ductile iron with wall thickness ranging from 2 – 3.7 mm was produced by inmold process. Structure, mechanical properties and computer simulations were investigated. Structural analysis of TWDI shows pearlitic-ferritic matrix free from chills and porosity. Mechanical testing disclose superior ultimate tensile strength (Rm, yield strength (Rp0,2 and slightly lower elongation (E of TWDI in comparison with forged control arm made of aluminium alloy (6061-T6. Moreover results of computer simulation of static loading for tested control arms are presented. Analysis show that the light-weight ductile iron casting can be loaded to similar working conditions as the forged Al alloy without any potential failures.

  10. Improving chill control in iron powder treated slightly hypereutectic grey cast irons

    OpenAIRE

    Iulian Riposan; Mihai Chisamera; Stelian Stan

    2011-01-01

    Recent studies revealed that in eutectic to slightly hypereutectic grey irons (CE = 4.3%-4.5%) the presence of austenite dendrites provides an opportunity to improve the cast iron properties, as a high number of eutectic cells are “reinforced” by austenite dendrites. An iron powder addition proved to be important by promoting dendritic austenite in hypereutectic irons, but was accompanied by adverse effect on the characteristics of potential nuclei for graphite. The purpose of the present pap...

  11. Residual Stresses and Fatigue of Shot Peened Cast Iron

    OpenAIRE

    Lundberg, Mattias

    2013-01-01

    The complex geometry of cylinder head in heavy-duty diesel engine makes grey cast iron or compact graphite iron a perfect material choice due to its castability, thermal conductivity and damping capacity. To increase the efficiency of the engine, the fatigue property of the material needs to be improved. Shot peening is often used to increase the fatigue strength of components. The benefits are associated with the compressive stresses induced and with surface hardening. In this research proje...

  12. 75 FR 70900 - Certain Iron Construction Castings From Brazil, Canada, and the People's Republic of China...

    Science.gov (United States)

    2010-11-19

    ... Construction Castings from Brazil, 75 FR 54596 (September 8, 2010). On November 2, 2010, the ITC determined... International Trade Administration Certain Iron Construction Castings From Brazil, Canada, and the People's... certain iron construction castings (``castings'') from Brazil, Canada, and the People's Republic of...

  13. Galvanic corrosion of copper-cast iron couples

    International Nuclear Information System (INIS)

    To ensure the safe encapsulation of spent nuclear fuel rods for geological disposal, SKB are considering using the Copper-Cast Iron Canister, which consists of an outer copper canister and an inner cast iron container. The canister will be placed into boreholes in the bedrock of a geologic repository and surrounded by bentonite clay. In the unlikely event of the outer copper canister being breached, water would enter the annulus between the inner and outer canister and at points of contact between the two metals there would be the possibility of galvanic interactions. Although this subject has been considered previously from both a theoretical standpoint and by experimental investigations there was a need for further experimental studies in support of information provided by SKB to the Swedish regulators (SKI). In the work reported here copper-cast iron galvanic couples were set up in a number of different environments representing possible conditions in the SKB repository. The tests investigated two artificial porewaters at 30 deg C and 50 deg C, under aerated and deaerated conditions. Tests were also carried out in a 30 wt% bentonite slurry made up in artificial groundwater. The potential of the couples and the currents passing between the coupled electrodes were monitored for several months. The effect of growing an oxide film on the surface of the cast iron prior to coupling it with copper was investigated. In addition, some crevice specimens based on the multi-crevice assembly (MCA) design were used to simulate the situation where the copper canister will be in direct contact with the cast iron inner vessel. The electrochemical results are presented graphically in the form of electrode potentials and galvanic corrosion currents as a function of time. The galvanic currents in aerated conditions were much higher than in deaerated conditions. For example, at 30 deg C, galvanic corrosion rates as low as 0.02 μm/year for iron were observed after deaeration, but

  14. Galvanic corrosion of copper-cast iron couples

    Energy Technology Data Exchange (ETDEWEB)

    Smart, N.R.; Rance, A.P.; Fennell, P.A.H. [Serco Assurance, Risley (United Kingdom)

    2005-01-01

    To ensure the safe encapsulation of spent nuclear fuel rods for geological disposal, SKB are considering using the Copper-Cast Iron Canister, which consists of an outer copper canister and an inner cast iron container. The canister will be placed into boreholes in the bedrock of a geologic repository and surrounded by bentonite clay. In the unlikely event of the outer copper canister being breached, water would enter the annulus between the inner and outer canister and at points of contact between the two metals there would be the possibility of galvanic interactions. Although this subject has been considered previously from both a theoretical standpoint and by experimental investigations there was a need for further experimental studies in support of information provided by SKB to the Swedish regulators (SKI). In the work reported here copper-cast iron galvanic couples were set up in a number of different environments representing possible conditions in the SKB repository. The tests investigated two artificial porewaters at 30 deg C and 50 deg C, under aerated and deaerated conditions. Tests were also carried out in a 30 wt% bentonite slurry made up in artificial groundwater. The potential of the couples and the currents passing between the coupled electrodes were monitored for several months. The effect of growing an oxide film on the surface of the cast iron prior to coupling it with copper was investigated. In addition, some crevice specimens based on the multi-crevice assembly (MCA) design were used to simulate the situation where the copper canister will be in direct contact with the cast iron inner vessel. The electrochemical results are presented graphically in the form of electrode potentials and galvanic corrosion currents as a function of time. The galvanic currents in aerated conditions were much higher than in deaerated conditions. For example, at 30 deg C, galvanic corrosion rates as low as 0.02 {mu}m/year for iron were observed after deaeration, but

  15. Mechanisms and mechanics of porosity formation in ductile iron castings

    Directory of Open Access Journals (Sweden)

    M. Perzyk

    2007-12-01

    Full Text Available Shrinkage defects in ductile iron castings can be of two basic types: shrinkage cavities associated with the liquid contraction prior to the expansion period of the iron as well as the porosity, which may appear even if the liquid shrinkage is fully compensated. In the present paper two possible mechanisms of the porosity are presented and analyzed. The first one is the Karsay’s mechanism based on the secondary shrinkage concept. The second one is the mechanism acting during the expansion period of the iron, first suggested by Ohnaka and co-authors and essentially modified by the present authors. The mechanical interactions between casting and mould are determined for the both mechanisms. Their analysis leads to the conclusion, that porosity forms during expansion period of the melt. The direct cause is the negative pressure which appears in the central part of the casting due to the differences in expansion coefficients of the fast cooling surface layer and slow cooling inner region. Observations concerning feeding behavior of ductile iron castings, based on this mechanism, agree well with industrial practice. The secondary shrinkage is not only needless to induce the porosity, but the corresponding mechanism of its occurrence, proposed by Karsay, does not seem to be valid.

  16. Solidification, processing and properties of ductile cast iron

    DEFF Research Database (Denmark)

    Tiedje, Niels Skat

    2010-01-01

    Ductile cast iron has been an important engineering material in the past 50 years. In that time, it has evolved from a complicated material that required the foundry metallurgist's highest skill and strict process control to being a commonly used material that can easily be produced with modern p...

  17. Solidification of Hypereutectic Thin Wall Ductile Cast Iron

    DEFF Research Database (Denmark)

    Pedersen, Karl Martin; Tiedje, Niels Skat

    2006-01-01

    Hypereutectic ductile iron was cast in green sand moulds with four plates with thickness of 1.5, 2, 3 and 4 mm in each mould. Temperatures were measured in the 3 and 4 mm plate. The temperature curves showed that eutectic solidification was divided into two stages: primary and secondary eutectic...

  18. Castability of ductile iron in thin walled castings (TWDI

    Directory of Open Access Journals (Sweden)

    M. Górny

    2008-10-01

    Full Text Available In work it has been presented results of influence of pouring temperature (Tp and carbon equivalent (CE on castability of ductile iron in thin walled castings with wall thickness of 1, 2 and 3 mm, respectively. Analysis was done on ductile iron with carbon equivalent ranging from 4.30 to 5.00 and pouring temperature varied from 1400 to 1500 oC. It has been shown that a statistical liner relationship exists between wall thickness and castability. Influence of CE and Tp on castability of cast iron flowing through channel with wall thickness of 2 and 3 mm can be presented by means of correlation equations (L = f(CE, Tp. Statistical analysis shows that pouring temperature has much higher influence on castability in comparison with influence of carbon equivalent.

  19. Structure and mechanical properties of vermicular cast iron in cylinder head casting

    Directory of Open Access Journals (Sweden)

    E. Guzik

    2009-01-01

    Full Text Available The paper discusses the problem of grain density and ferrite content in microstructure of vermicular graphite iron cast in bars of different section diameters and cylinder head casting. The experimental results regarding the section effect demonstrate that the nodule count, grain density and ferrite content are all function of the cast bar diameter in this particular case ranging from 0.6 to 8.0 cm and microstructure and mechanical properties in the cylinder head. The nodule count (or grain density has been reported to increase, while ferrite content was decreasing with decreasing casting diameter. The density number of the grains Nv has been related (by regression analysis to the undercooling degree

  20. Casting Ductile Iron in Layer Moulds Made from Ecological Sands

    Directory of Open Access Journals (Sweden)

    M. Rączka

    2012-09-01

    Full Text Available The article contains the results of tests performed under the target project in Hardtop Foundry Charsznica.The objective of the tests and studies was to develop a technology of making high-quality ductile iron castings, combined witheffective means of environmental protection. The studies presented in this article related to castings weighing from 1 to 300 kg made from ductile iron of grades 400-15 and 500-7, using two-layer moulds, where the facing and core sand was the sand with an alkaline organic binder, while backing sand was the sand with an inorganic geopolymer binder.A simplified method of sand reclamation was applied with possible reuse of the reclaim as an addition to the backing sand. The castiron spheroidising treatment and inoculation were selected taking into account the specific conditions of Hardtop Foundry. A pilot batch of castings was made, testing the gating and feeding systems and using exothermic sleeves on risers. The study confirmed the validity of the adopted concept of making ductile iron castings in layer moulds, while maintaining the content of sand with an organic binder at a level of maximum 15%.

  1. Microstructure and properties of cast iron after laser surface hardening

    Directory of Open Access Journals (Sweden)

    Stanislav

    2013-12-01

    Full Text Available Laser surface hardening of cast iron is not trivial due to the material’s heterogeneity and coarse-grained microstructure, particularly in massive castings. Despite that, hardening of heavy moulds for automotive industry is in high demand. The present paper summarises the findings collected over several years of study of materials structure and surface properties. Phase transformations in the vicinity of graphite are described using examples from production of body parts in automotive industry. The description relates to formation of martensite and carbide-based phases, which leads to hardness values above 65 HRC and to excellent abrasion resistance.

  2. Some problems in the production of ductile irons by investment casting

    OpenAIRE

    Yu Bo; Cai Qizhou; Wei Bokang

    2008-01-01

    Because of the excellent performance of ductile irons and the unique superiority of investment casting, the preparation of complicated and thin-wall ductile iron castings by investment casting shows a good development prospect. In this present work, combined with the actual product experiments, the characteristics of shell making, spheroidization, inoculation and defect prevention are presented, and some suggestions are given for investment casting of ductile iron.

  3. Some problems in the production of ductile irons by investment casting

    Directory of Open Access Journals (Sweden)

    Yu Bo

    2008-02-01

    Full Text Available Because of the excellent performance of ductile irons and the unique superiority of investment casting, the preparation of complicated and thin-wall ductile iron castings by investment casting shows a good development prospect. In this present work, combined with the actual product experiments, the characteristics of shell making, spheroidization, inoculation and defect prevention are presented, and some suggestions are given for investment casting of ductile iron.

  4. Ductile cast iron obtaining by Inmold method with use of LOST FOAM process

    Directory of Open Access Journals (Sweden)

    T. Pacyniak

    2010-01-01

    Full Text Available The possibility of manufacturing of ductile cast iron castings by Inmold method with use of LOST FOAM process was presented in this work. The spheroidization was carried out by magnesium master alloy in amounts of 1% casting mass. Nodulizer was located in the reactive chamber in the gating system made of foamed polystyrene. Pretests showed, that there are technical possibilities of manufacturing of casts from ductile cast iron in the LOST FOAM process with use of spheroidization in mould.

  5. High temperature corrosion of cast irons and cast steels in dry air

    Energy Technology Data Exchange (ETDEWEB)

    Tholence, F.; Norell, M. [Chalmers Univ. of Technology, Goeteborg (Sweden). Dept. of Engineering Metals

    2001-07-01

    The oxidation in dry air of four cast alloys intended for exhaust gas systems has been examined. Particular interest was directed to how the oxide growth was related to the microstructures. The examined alloys were two cast ductile irons, a SiMo alloy (Fe3,86Si0,6Mo3C) and a Ni-Resist alloy (Fe32Ni5,3Si2,1C), and two cast stainless steels, one ferritic (Fe18Cr2,1Mn0,32C) and one austenitic (Fe20Cr9Ni0,47C). Coupons were oxidised for 50 h at temperatures between 650 C and 1050 C. The samples were characterised by using XRD, SEM/EDX and AES. As expected, the overall oxide thickness increased with temperature and partial spallation occurred at the highest temperatures for all alloys. Porous Fe oxide nodules nucleate at the graphite nodules on the ductile irons. These Fe-oxide nodules formed above a continuous layer of Fe-Si-oxide for the SiMo and mixed Fe-Ni-Si oxides for the Ni-Resist. The total oxide thickness is about (60 {mu}m). Thick oxides at the interdendritic regions in the cast steels were attributed to non-Cr-carbides. Segregation of Cr directed the formation of iron oxide nodules to the centre of the dendrites in the austenitic alloy. (orig.)

  6. New developments in high quality grey cast irons

    Directory of Open Access Journals (Sweden)

    Iulian Riposan

    2014-07-01

    Full Text Available The paper reviews original data obtained by the present authors, revealed in recent separate publications, describing specific procedures for high quality grey irons, and reflecting the forecast needs of the worldwide iron foundry industry. High power, medium frequency coreless induction furnaces are commonly used in electric melting grey iron foundries. This has resulted in low sulphur (1,500 °C, contributing to unfavourable conditions for graphite nucleation. Thin wall castings are increasingly produced by these electric melt shops with a risk of greater eutectic undercooling during solidification. The paper focused on two groups of grey cast irons and their specific problems: carbides and graphite morphology control in lower carbon equivalent high strength irons (CE=3.4%-3.8%, and austenite dendrite promotion in eutectic and slightly hypereutectic irons (CE=4.1%-4.5%, in order to increase their strength characteristics. There are 3 stages and 3 steps involving graphite formation, iron chemistry and iron processing that appear to be important. The concept in the present paper sustains a threestage model for nucleating flake graphite [(Mn,XS type nuclei]. There are three important groups of elements (deoxidizer, Mn/S, and inoculant and three technological stages in electric melting of iron (superheat, pre-conditioning of base iron, final inoculation. Attention is drawn to a control factor (%Mn x (%S ensuring it equals to 0.03 – 0.06, accompanied by 0.005wt.%–0.010wt.% Al and/or Zr content in inoculated irons. It was found that iron powder addition promotes austenite dendrite formation in eutectic and slightly eutectic, acting as reinforcement for the eutectic cells. But, there is an accompanying possible negative influence on the characteristics of the (Mn,XS type graphite nuclei (change the morphology of nuclei from polygonal compact to irregular polygonal, and therefore promote chill tendency in treated irons. A double addition (iron

  7. New developments in high quality grey cast irons

    Institute of Scientific and Technical Information of China (English)

    Iulian Riposan; Mihai Chisamera; Stelian Stan

    2014-01-01

    The paper reviews original data obtained by the present authors, revealed in recent separate publications, describing speciifc procedures for high quality grey irons, and relfecting the forecast needs of the worldwide iron foundry industry. High power, medium frequency coreless induction furnaces are commonly used in electric melting grey iron foundries. This has resulted in low sulphur (1,500 °C), contributing to unfavourable conditions for graphite nucleation. Thin wall castings are increasingly produced by these electric melt shops with a risk of greater eutectic undercooling during solidiifcation. The paper focused on two groups of grey cast irons and their speciifc problems: carbides and graphite morphology control in lower carbon equivalent high strength irons (CE=3.4%-3.8%), and austenite dendrite promotion in eutectic and slightly hypereutectic irons (CE=4.1%-4.5%), in order to increase their strength characteristics. There are 3 stages and 3 steps involving graphite formation, iron chemistry and iron processing that appear to be important. The concept in the present paper sustains a three-stage model for nucleating flake graphite [(Mn,X)S type nuclei]. There are three important groups of elements (deoxidizer,Mn/S, and inoculant) and three technological stages in electric melting of iron (superheat, pre-conditioning of base iron, ifnal inoculation). Attention is drawn to a control factor (%Mn) x (%S) ensuring it equals to 0.03- 0.06, accompanied by 0.005wt.%-0.010wt.% Al and/or Zr content in inoculated irons. It was found that iron powder addition promotes austenite dendrite formation in eutectic and slightly eutectic, acting as reinforcement for the eutectic cells. But, there is an accompanying possible negative influence on the characteristics of the (Mn,X)S type graphite nuclei (change the morphology of nuclei from polygonal compact to irregular polygonal, and therefore promote chill tendency in treated irons). A double addition (iron powder + inoculant

  8. Effect of potassium on as-cast microstructure of a hypereutectic high chromium cast iron

    OpenAIRE

    Liu Qing; Yang Hua; Ding Haimin

    2011-01-01

    The present work mainly evaluates the effect of potassium (K) on as-cast microstructure of a hypereutectic high chromium cast iron by means of a field emission scanning electron microscope (FESEM) and an X-ray diffractometer using CuKα radiation with a 2θ range of 30-130°. Results showed that, with the addition of K-containing modifier, the large lath-like and/or rod-like primary M7C3 carbides can be modified to the hexagonal prisms, and the eutectic carbides can also be refined. In addition,...

  9. Mechanism of silicon influence on the chill of cast iron

    Directory of Open Access Journals (Sweden)

    E. Fraś

    2007-12-01

    Full Text Available In this work an analytical solution of general validity is used to explain mechanism of the silicon influence on the absolute chill tendency (CT and chill (w of cast iron. It is found that CT can be related to nucleation potential of graphite (Nv, growth parameter (μ of eutectic cells, temperature range (ΔTsc and the pre-eutectic austenite volume fraction (fγ. It has been shown that silicon additions: a impede the growth of graphite eutectic cells, μ, b expands the temperature range ΔTsc, c increases the nucleation potential of graphite Nv, d lowers the pre-eutectic austenite volume fraction, fγ. and in consequence the absolute chilling tendency, CT decreases. The minimum wall thicknesses for chilled castings, or chill widths (w in wedge shaped castings is related to CT and as silcon contents increases, the w value also increases.

  10. Fracture toughness behaviour of ferritic ductile cast iron

    International Nuclear Information System (INIS)

    The static rate fracture toughness of a series of eight heats of ductile cast iron has been measured. Samples from each heat were tested in a heat treated condition which produced a fully ferritic matrix. The chemical composition and the microstructural feature size has also been measured directly from each specimen tested. A multiple linear regression method was used to establish a simple mathematical relationship between fracture toughness and the composition and microstructure. Fracture toughness was found to be strongly associated with the spacing (or size) of the graphite nodules in these fully ferritic ductile cast irons. Other features, including the composition, the ferrite grain size, or the amount of graphite (over the ranges examined), did not strongly influence the fracture toughness. Fracture toughness also did not correlate with tensile properties (i.e. strength or ductility) in these alloys. (author)

  11. SURFACE CAST IRON STRENGTHENING USING COMBINED LASER AND ULTRASONIC PROCESSING

    Directory of Open Access Journals (Sweden)

    O. Devojno

    2013-01-01

    Full Text Available The paper provides an analysis of ultrasonic surface plastic deformation and subsequent laser thermal strengthening of gray cast iron parts in the regime of hardening from a solid state with the purpose to obtain strengthened surface layers of bigger depth and less roughness of the processed surface. Program complex ANSYS 11.0 has been used for calculation of temperature fields induced by laser exposure.  The appropriate regime of laser processing without surface fusion has been selected on the basis of the applied complex. The possibility of displacement in the bottom boundary of α–γ-transformation temperature  for СЧ20 with 900 °С up to 800 °С is confirmed due to preliminary ultrasonic surface plastic deformation of the surface that allows to expand technological opportunities of laser quenching  of gray  cast iron from a solid state. 

  12. Role of yttrium in heavy section spheroidal graphite cast iron

    International Nuclear Information System (INIS)

    Magnesium ferrosilicon alloys (Mg = 5-7%) are widely used abroad, while rare earth-magnesium ferrosilicon alloys (Mg = 8-10%, Ce RE = 5-9%) are used predominantly in China. Recently, due to the exploitation of natural resources of yttrium rare earth at home, a new type of alloy--yttrium based-rare earth ferrosilicon (YRE=25-40%, Si=40%) has been developed and put into trail as a substitute for conventional rare earth magnesium ferrosilicon alloy in some of the foundries for manufacturing heavy section spheroidal graphite cast iron. In this paper the effect of yttrium on mechanical properties and microstructures of heavy section spheroidal graphite cast iron are studied. Some simulating experiments were carried out in laboratory

  13. Age Strengthening of Gray Cast Iron Phase III

    Energy Technology Data Exchange (ETDEWEB)

    Von L. Richards; Wayne Nicola

    2003-06-26

    The primary objective of this research is to identify the age strengthening mechanism in gray and ductile cast iron, and to quantify the parameters that control it. It is also to contribute to a new predictive model for gray and ductile iron strength and hardness. This work shows that age strengthening occurs on a sigmoidal-logarithmic scale in gray and ductile cast irons, to a statistically significant extent. This is similar to Avrami-Johnson-Mehl kinetics for phase transformations in metals. It occurs in both cupola-melted iron and induction melted iron. However, it does not happen in all compositions. We have developed some understanding of the process. Data suggests that nitrogen and nitride-forming trace elements have a significant role in the process, but that is yet not fully characterized. Also, the time dependence of the bulk hardness and strength increase, the nano-scale precipitation evidence from neutron scattering, differential scanning calorimetry results and matrix micro-hardness increase in ferrite all indicate that age strengthening occurs by a precipitation or pre-precipitate cluster formation mechanism.

  14. The influence of cooling rate on the hardness of cast iron with nodular and vermicular graphite

    Directory of Open Access Journals (Sweden)

    M. S. Soiński

    2008-12-01

    Full Text Available The paper presents hardness changes for cast iron with nodular and vermicular graphite, determined within the separately cast test blocks. Investigation has comprised cast irons with similar ferrite and pearlite fractions in the metal matrix. The hardness measurements have been performed by Brinell method for samples taken both from an edge and from the centre of a Y block (for nodular cast iron or of a reversed U block (in the case of vermicular cast iron. Investigations have pertained both to the test parts and to the sinkheads of the test blocks. Hardness measurements have been completed with metallographic examination.

  15. The effect of microstructure of low-alloy spheroidal cast iron on impact strength

    Directory of Open Access Journals (Sweden)

    T. Szykowny

    2010-01-01

    Full Text Available The study presents an evaluation of the effect of microstructure of low-alloy spheroidal cast iron on impact strength within the temperature range from –60 to 100°C. Analyses were conducted on one type of cast iron containing 0.51% Cu and 0.72% Ni. Cast iron was austempered or normalized. Values of KCV and static mechanical properties were determined. Structural and fractographic analyses were based on light and scanning microscopy as well as X-ray diffraction. It was found that thermal processing considerably improves impact strength in relation to cast iron after casting. At the same time static mechanical properties are enhanced.

  16. Identification Trial of Crystallization Parameters of Modified Chromium Cast Iron

    OpenAIRE

    A. Studnicki

    2007-01-01

    In the paper results of researches of abrasion-resisting chromium cast iron inoculated with boron carbide B4C primary crystallization are presented. The main aim of work was make an attempt to identification of crystallization parameters that changed in reason of inoculation. Essential primary crystallization parameters, with the help of which, will be possible to evaluate the inoculation capacity were searched. It was found that in the result of inoculant actions characteristic temperatures ...

  17. Nondestructive characterization of ductile cast iron by magnetic adaptive testing

    Czech Academy of Sciences Publication Activity Database

    Vértesy, G.; Uchimoto, T.; Tomáš, Ivan; Takagi, T.

    2010-01-01

    Roč. 322, č. 20 (2010), s. 3117-3121. ISSN 0304-8853 R&D Projects: GA ČR GA101/09/1323; GA AV ČR 1QS100100508 Institutional research plan: CEZ:AV0Z10100520 Keywords : magnetic NDE * magnetic adaptive testing * magnetic hysteresis * cast iron Subject RIV: BM - Solid Matter Physics ; Magnetism Impact factor: 1.689, year: 2010

  18. Iron-based bulk metallic glasses - Optimization of casting

    Czech Academy of Sciences Publication Activity Database

    Stloukal, Ivo; Král, Lubomír; Čermák, Jiří

    Ostrava: Tanger s. r. o, 2009, s. 481-487. ISBN 978-80-87294-04-8. [METAL 2009. Mezinárodní konference metalurgie a materiálů /18./. Hradec nad Moravicí (CZ), 19.05.2009-21.05.2009] R&D Projects: GA ČR GA106/08/1241 Institutional research plan: CEZ:AV0Z20410507 Keywords : bulk metallic glasses * iron-based alloy * casting optimization Subject RIV: BJ - Thermodynamics

  19. Niobium alloying effect in high carbon equivalent grey cast iron

    OpenAIRE

    Zhou Wenbin; Zhu Hongbo; Zheng Dengke

    2011-01-01

    The effect of niobium on the formation of NbC phase and solidification structure in high carbon equivalent grey cast iron was investigated. The experimental results indicated that an increase in the niobium content is favorable to refining the graphite and eutectic cell; and the pearlite lamellar spacing is reduced. Based on the thermodynamic calculation the formation of NbC is prior to the eutectic reaction. The reduction in the pearlite lamellar spacing is mainly attributed to the decrease ...

  20. Solidification of Hypereutectic Thin Wall Ductile Cast Iron

    OpenAIRE

    Pedersen, Karl Martin; Tiedje, Niels Skat

    2006-01-01

    Hypereutectic ductile iron was cast in green sand moulds with four plates with thickness of 1.5, 2, 3 and 4 mm in each mould. Temperatures were measured in the 3 and 4 mm plate. The temperature curves showed that eutectic solidification was divided into two stages: primary and secondary eutectic solidification. The first stage, which was relatively short, had none or very little recalescence. Further under cooling, followed by reheating during recalescence, was necessary to initiate the secon...

  1. Performance characteristics of mill rolls from graphite chromium cast iron

    OpenAIRE

    Lecomte-Beckers, Jacqueline; Terziev, L.; Breyer, J. P.

    2000-01-01

    The main requirements for the development of a new grade for the later finishing section of the mill are : good oxidation and thermal behaviour, high wear resistance, good resistance to rolling incidents. The approach of Marichal Ketin to improve the rolling performances in the last finishing stands is presented. The Hi-Cr cast iron possesses excellent wear resistance due to the presence of hard chromium carbides, but its thermal conductivity and sticking properties are fairly low. A graphite...

  2. Improving chill control in iron powder treated slightly hypereutectic grey cast irons

    Directory of Open Access Journals (Sweden)

    Iulian Riposan

    2011-05-01

    Full Text Available Recent studies revealed that in eutectic to slightly hypereutectic grey irons (CE = 4.3%-4.5% the presence of austenite dendrites provides an opportunity to improve the cast iron properties, as a high number of eutectic cells are “reinforced” by austenite dendrites. An iron powder addition proved to be important by promoting dendritic austenite in hypereutectic irons, but was accompanied by adverse effect on the characteristics of potential nuclei for graphite. The purpose of the present paper is to investigate the solidification pattern of these irons. Chill wedges with different cooling moduli (CM = 0.11 – 0.43 cm were poured in resin bonded sand and metal moulds. Relative clear / mottled / total chill measurement criteria were applied. Iron powder additions led to a higher chill tendency, while single inoculation showed the strongest graphitizing effect. The various double treatments show an intermediate position, but the inoculant added after iron powder appears to be the most effective in reducing base iron chill tendency, for all cooling moduli and chill evaluation parameters. This performance reflects the improved properties of (Mn,XS polygonal compounds as nucleation sites for graphite, especially in resin bonded sand mould castings. Both austenite and graphite nucleation benefit from a double addition of iron powder + inoculant, with positive effect on the final structure and chill tendency.

  3. Structure fields in the solidifying cast iron roll

    Directory of Open Access Journals (Sweden)

    W.S. Wołczyński

    2010-01-01

    Full Text Available Some properties of the rolls depend on the ratio of columnar structure area to equiaxed structure area created during roll solidification. The transition is fundamental phenomenon that can be apply to characterize massive cast iron rolls produced by the casting house. As the first step of simulation, a temperature field for solidifying cast iron roll was created. The convection in the liquid is not comprised since in the first approximation, the convection does not influence the studied occurrence of the (columnar to equiaxed grains transition in the roll. The obtained temperature field allows to study the dynamics of its behavior observed in the middle of the mould thickness. This midpoint of the mould thickness was treated as an operating point for the transition. A full accumulation of the heat in the mould was postulated for the transition. Thus, a plateau at the curve was observed at the midpoint. The range of the plateau existence corresponded to the incubation period , that appeared before fully equiaxed grains formation. At the second step of simulation, behavior of the thermal gradients field was studied. Three ranges within the filed were visible: EC→EC→EC→EC→(tTECtt↔RERCtt↔a/ for the formation of columnar structure (the C – zone: ( and 0>>T&0>>=−>−=REREttGttG.The columnar structure formation was significantly slowed down during incubation period. It resulted from a competition between columnar growth and equiaxed growth expected at that period of time. The 0≈=−=RERCttGttG relationship was postulated to correspond well with the critical thermal gradient, known in the Hunt’s theory. A simulation was performed for the cast iron rolls solidifying as if in industrial condition. Since the incubation divides the roll into two zones: C and E; (the first with columnar structure and the second with fully equiaxed structure some experiments dealing with solidification were made on semi-industrial scale.

  4. Effect of Chemical Composition on Number of Eutectic Colonies in Ni-Mn-Cu Cast Iron

    Directory of Open Access Journals (Sweden)

    A. Janus

    2013-01-01

    Full Text Available Determined were direction and intensity of influence of alloying additions on the number of eutectic graphite colonies in austenitic cast iron Ni-Mn-Cu. Chemical composition of the cast iron was 1.7 to 3.3% C, 1.4 to 3.1% Si, 2.8 to 9.9% Ni, 0.4 to 7.7% Mn, 0 to 4.6% Cu,0.14 to 0.16% P and 0.03 to 0.04% S. Analysed were structures of mottled (20 castings and grey (20 castings cast iron. Obtained wereregression equations determining influence intensity of individual components on the number of graphite colonies per 1 cm2 (LK. It wasfound that, in spite of high total content of alloying elements in the examined cast iron, the element that mainly decides the LK value is carbon, like in a plain cast iron.

  5. Influence of dust addition from cast iron production on bentonite sand mixture properties

    Directory of Open Access Journals (Sweden)

    P. Gengeľ

    2010-04-01

    Full Text Available In cast iron foundry operations like melting, casting, feetling, casts cleaning and grinding of a high amount of dusts are produced. Threekinds of dusts from different parts of cast iron foundry were analysed; chemical analyses, granulometric analyses and microscopic analyseswere carried out. The bentonite sand mixtures with different portion of dusts were prepared. Technological properties of prepared sandmixtures (compression strength, shearing strength and permeability were measured.

  6. Testing of heating and cooling process of ADI cast iron with use of ATND method

    Directory of Open Access Journals (Sweden)

    A. Białobrzeski

    2008-10-01

    Full Text Available ADI (Austempered Ductile Iron cast iron, owing to its unique combination of high tensile strength and abrasion resistance with very goodplasticity, founds implementation in many branches of industry as a substitute of alloy cast steel and carburized or heat treated steels. Inspite of its solid position among producers and recipients of castings, there are still undertaken studies aimed at perfection of its propertiesand recognition of mechanisms enabling obtaining such properties.The paper presents implementation of thermal-voltage-derivative (ATND method to registration of heating and cooling course of ADIcast iron with EN-GJS-1200-2 grade. ADI cast iron with EN-GJS-1200-2 grade underwent the study. Heat treatment of the cast iron wasperformed in Foundry Institute with use of LT ADI-350/1000 processing line. Results obtained from the testing illustrate in graphic formregistered heating and cooling curves of investigated cast irons obtained with use of the ATND method.

  7. A Methodology to Predict Uniform Material Fatigue Life of Cast Iron: Law for Cast Iron%A Methodology to Predict Uniform Material Fatigue Life of Cast Iron: Law for Cast Iron

    Institute of Scientific and Technical Information of China (English)

    Sinan Korkmaz

    2011-01-01

    Mechanical, physical and manufacturing properties of east iron make it attractive for many fields of application, such as cranks and cylinder holds. As in design of all metals, fatigue life prediction is an intrinsic part of the design process of structural sections that are made of cast iron. A methodology to predict high-cycle fatigue life of cast iron is proposed. Stress amplitude-strain amplitude, strain amplitude-number of loading cycles relationships of cast iron are investigated. Also, fatigue life prediction in terms of Smith, Watson and Topper parameter is carried out using the proposed method. Results indicate that the analytical outcomes of the proposed methodology are in good accordance with the experimental data for the two studied types of cast iron: EN-GJS-400 and EN-GJS-600.

  8. Thermal analysis of ductile iron in thin walled casting

    Directory of Open Access Journals (Sweden)

    M. Górny

    2007-12-01

    Full Text Available Hypereutectic ductile iron was cast in self hardening moulding sand to produce castings with the shape of Archimedes spirals and with wall thickness of 1, 2 and 3 mm. Inmould technique was used to produce thin wall ductile iron (TWDI. In this work it has been carried out thermal analysis in spiral with 3 mm wall thickness. The present work provides results of thermal analysis, that are initial temperature of metal in mould cavity, velocity of metal stream as well as solidification time. Measurement of temperature shows that there is essential its drop during filling of mould cavity and amounts 230 oC for distance 700 mm from the beginning of spiral. On the basic on first derivative of temperature versus time characteristic solidification points were distinguish, namely solidification of primary graphite, austenite dendrite and eutectic. Experimental measurements of temperature drop during filling of mould cavity along with microscopic examinations of castings structure can be used to verify computer modeling and simulation of fluid flow and thermal field in TWDI.

  9. Role of the preliminary heat treatment in anisothermic eutectoid change of the cast iron

    OpenAIRE

    T. Szykowny; T. Giętka; M. Trepczyńska - Łent

    2011-01-01

    Preliminary heat treatment, preceding continuous cooling of the iron casting, assumed in the research, complies with the applied in prac- tice single normalization, double normalization or normalization with slow cooling. In each of these cases continuous cast iron cooling has been begun from the same temperature 925°C. CCT diagrams have been made with use of metallographic method. The mechanism, kinet- ics and the final structure of eutectoid change of the cast iron after such treatment have...

  10. Control of microstructure of cast irons Indefinite Chill Double Pour-ICDP

    OpenAIRE

    T.Válek; Hampl, J

    2011-01-01

    ICDP cast irons designated for working layer of centrifugal cylinders of rolling mill must have precisely defined properties. The most closely observed parameters of the ICDP (Indefinite Child Double Pour) cast irons are the following: the amount of graphite in a microstructure and hardness of base metal material. Secretion of graphite in cast iron with ledeburitic basic metal compound is a complex process that can be controlled and managed with the use of thermal analysis. On the basis of th...

  11. A Study of the Microstructure and Mechanical Properties of Continuously Cast Iron Products

    Directory of Open Access Journals (Sweden)

    Bockus, S.

    2006-01-01

    Full Text Available The horizontal continuous casting has a lot of advantages in comparison with traditional casting methods. But it has a few disadvantages and unsolved problems. The objective of this research was the experimental investigation of the effect of chemical composition of cast iron and the casting conditions on the microstructure and properties of continuously cast ingots. As a result, tensile strength, Brinell hardness, and pearlite content increased with increasing Cr, Cu, and Sb additions and decreasing carbon equivalent. As for microstructure of graphite, higher silicon to carbon ratio and lower solidification rate decreased a zone of interdendritic graphite. Nomograph of continuously cast iron structure was made.

  12. Effect of Heat Treatment on Mechanical Property of High Cr-W Cast Iron

    Institute of Scientific and Technical Information of China (English)

    Liu Jianping; Li Lixia

    2007-01-01

    The microstructure of high Cr-W cast iron after heat treatment were analyzed, and the effect of various heat treatment temperature and time on mechanical properties of high Cr-W cast iron were studied, and the best process parameter of heat treatment was provided in this paper. The results show that the heat treatment can improve the mechanical property of high Cr-W cast iron, and higher synthetic mechanical property of high Cr-W cast iron can be obtained when treated with normalization at 980℃ for 2h and tempered at 400℃ for 2h.

  13. Effect of chemical composition and superheat on macrostructure of high Cr white iron castings

    Energy Technology Data Exchange (ETDEWEB)

    Dogan, Omer N.

    2005-08-01

    White cast irons are frequently used in applications requiring high wear resistance. High Cr white cast irons have a composite microstructure composed of hard (Fe,Cr)7C3 carbides in a steel matrix. Previous research has indicated that the equiaxed region of these high Cr white iron castings is much more wear resistant under high stress abrasive conditions than the columnar region, when the carbides are oriented perpendicular to the wear surface. In the present study, the effect of both the chemical composition, particularly carbon content, and the pouring superheat of the melt on the macrostructure of high Cr white iron castings is investigated.

  14. Identification Trial of Crystallization Parameters of Modified Chromium Cast Iron

    Directory of Open Access Journals (Sweden)

    A. Studnicki

    2007-07-01

    Full Text Available In the paper results of researches of abrasion-resisting chromium cast iron inoculated with boron carbide B4C primary crystallization are presented. The main aim of work was make an attempt to identification of crystallization parameters that changed in reason of inoculation. Essential primary crystallization parameters, with the help of which, will be possible to evaluate the inoculation capacity were searched. It was found that in the result of inoculant actions characteristic temperatures were changed and time of primary crystallization was decreased. For tests the new broadened Derivative Thermal Analysis method, in which three samples with different solidification module were applied, was used. Thanks to this inoculation capacity in casts with significant diversified self-cooling ranges was possible to observe.

  15. Application of evolutionary algorithm for cast iron latent heat identification

    Directory of Open Access Journals (Sweden)

    J. Mendakiewicz

    2008-12-01

    Full Text Available In the paper the cast iron latent heat in the form of two components corresponding to the solidification of austenite and eutectic phases is assumed. The aim of investigations is to estimate the values of austenite and eutectic latent heats on the basis of cooling curve at the central point of the casting domain. This cooling curve has been obtained both on the basis of direct problem solution as well as from the experiment. To solve such inverse problem the evolutionary algorithm (EA has been applied. The numerical computations have been done using the finite element method by means of commercial software MSC MARC/MENTAT. In the final part of the paper the examples of identification are shown.

  16. Model of Primary Austenite Dendrite Structure in Hypoeutectic Cast Iron

    Institute of Scientific and Technical Information of China (English)

    2003-01-01

    The solidification of primary austenite in hypoeutectic gray cast iron was studied by stepped grinding and quantitative metallography. The dendrite structure of primary austenite can be described by three models: typical dendrite crystal model, metamorphic dendrite crystal model and network dendrite crystal model. The dendrite crystals formed according to 3rd model is much more than those formed according to other models in this experiment. The primary austenites are connected each other, and the primary stems of austenite could be regarded as secondary arms and vice versa.

  17. Gradient method of cast iron latent heat identification

    Directory of Open Access Journals (Sweden)

    E. Majchrzak

    2007-12-01

    Full Text Available In the paper the cast iron latent heat in the form of three components corresponding to solidification of austenite and eutectic phases is identified. The basic information concerning the form of adequate functions approximation has been taken on the basis of cooling curve and temperature derivative courses found by means of the TDA technique. On the stage of inverse problem solution the gradient method has been used. The numerical computations have been done using the finite difference method. In the final part of the paper the example of latent heat identification is shown.

  18. Primary and secondary crystallization of modified hypoeutectic chromium cast iron

    Directory of Open Access Journals (Sweden)

    A. Studnicki

    2010-04-01

    Full Text Available The paper presents investigations of crystallization of modified hypoeutectic wear resistant chromium cast iron which contains carbon about 2% and chromium on three levels (12%, 18% and 25%. Three substances were applied to the modification ( boron carbide (B4C, ferroniobium (FeNb and mixture of ferroniobium and mischmetal (RE. The investigations of crystallization were conducted the DTA method in DTA-C and DTA-Is testers. The influence on the course of the process of primary and secondary crystallization was observed.

  19. Effect of potassium on as-cast microstructure of a hypereutectic high chromium cast iron

    Directory of Open Access Journals (Sweden)

    Liu Qing

    2011-05-01

    Full Text Available The present work mainly evaluates the effect of potassium (K on as-cast microstructure of a hypereutectic high chromium cast iron by means of a field emission scanning electron microscope (FESEM and an X-ray diffractometer using CuKα radiation with a 2θ range of 30-130°. Results showed that, with the addition of K-containing modifier, the large lath-like and/or rod-like primary M7C3 carbides can be modified to the hexagonal prisms, and the eutectic carbides can also be refined. In addition, the carbides are distributed much more homogeneously in the matrix. The modification effect of K is due to its aggregation at the liquid-solid interface and the adsorption on the relatively fast growing planes during the solidification, which influence the growth rates of different crystal planes and lead to the modification of the carbides.

  20. Investigation of the tensile properties of continuous steel wire-reinforced gray cast iron composite

    International Nuclear Information System (INIS)

    Research highlights: → Metal matrix composite (MMC) is an important structural material. → Gray cast irons as a matrix material in MMC have more advantages than other cast irons. → Interface greatly determines the mechanical properties of MMC. → Interface formed by diffusion of carbon atoms. → While decarburizing takes place in gray cast iron, carburiszing takes place in steel near the interface. - Abstract: The aim of the present study was to improve the tensile properties of gray cast iron by reinforcing the material with a steel wire. The composite was produced by sand mold casting, and the specimens were normalized by applying heat treatments at 800 deg. C, 850 deg. C, and 900 deg. C. Tension tests were conducted on gray cast iron and composite specimens, and the microstructure of the specimens was examined with an optical microscope. The fracture surface of the tension test specimens was examined with a scanning electron microscope (SEM), and graphite-free transition regions with high degrees of hardness were observed due to the diffusion of carbon from the cast iron to the steel wire. The microstructure of the transition region (fine pearlitic phase with partially dissolved graphite flakes) and the bond quality in the transition region increased the tensile properties of cast iron composites. Also, it is concluded that the tensile properties of gray cast iron increased with an increase in the normalization temperature.

  1. Development of a manufacturing technology of compacted graphite iron castings from a cupola furnace

    OpenAIRE

    O. Bouska; J. Heunisch; A. Zadera; K. Nedelova; F. Kobersky

    2012-01-01

    Compacted graphite iron, also known as vermicular cast iron or semiductile cast iron is a modern material, the production of which is increasing globaly. Recently this material has been very often used in automotive industry. This paper reviews some findigs gained during the development of the manufacturing technology of compacted graphite iron under the conditions in Slévárna Heunisch Brno, Ltd. The new technology assumes usage of cupola furnace for melting and is beeing developed for produc...

  2. Optimization of casting defects analysis with supply chain in cast iron foundry process

    Directory of Open Access Journals (Sweden)

    C. Narayanaswamy

    2016-10-01

    Full Text Available Some of the foundries are in need of meeting production targets and due to the urgency they ignore the rejections. The objective of this paper is to analyze the various defects, [1] from molding process in a cast iron foundry. The Failure Mode Effects Analysis (FMEA in quality control [2-6] with suitable supply chain for mold making process considering rejection rates are identified and analyzed in terms of Risk Priority Number (RPN to prioritize the attention for each of the problem. The optimum levels of selected parameters [7] are obtained in this analysis.

  3. Graphite Nodule and Cell Count in Cast Iron

    Directory of Open Access Journals (Sweden)

    E Fraś

    2007-07-01

    Full Text Available In this work, a model is proposed for heterogeneous nucleation on substrates whose size distribution can be described by the Weibull statistics. It is found that the nuclei density, Nnuc can be given in terms of the maximum undercooling, ΔTm by Nnuc = Ns exp(-b/ΔTm; where Ns is the density of nucleation sites in the melt and b is the nucleation coefficient (b > 0 . When nucleation occurs on all the possible substrates, the graphite nodule density, NV,n or eutectic cell density NV after solidification equals Ns. In this work, measurements of NV,n and NV values were carried out on experimental nodular and flake graphite iron castings processed under various inoculation conditions. The volumetric nodule NV,,n or graphite eutectic cell NV count, were estimated from the area nodule count, NA,n or eutectic cell count NA on polished cast iron surface sections by stereological means. In addition, maximum undercoolings, ΔTm were measured using thermal analysis. The experimental outcome indicates that volumetric nodule NV,n or graphite eutectic cell NV count can be properly described by the proposed expression NV,,n = NV = Ns exp(-b/ΔTm. Moreover, the Ns and b values were experimentally determined. In particular, the proposed model suggests that the size distribution of nucleation sites is exponential in nature.

  4. Structure of ductile iron in thin walled castings

    Directory of Open Access Journals (Sweden)

    M. Górny

    2007-12-01

    Full Text Available It this work it has been shown that it is possible to produce thin wall ductile iron (TWDI castings with considerably length using Archimedes spiral with wall thickness of 1, 2 and 3 mm. Inmould technique was used to produce TWDI. It has been estimated castability and metallographic investigations were made using different moulding materials. From castability measurements result that it is possible to obtain thin wall ductile iron castings with wall thickness down to 1 mm with castability of 200 mm. Using mould with small ability to absorb heat castability increases twice. At wall thickness equal 3 mm castability reaches 1000 mm and using LDASC sand its value increases to over 1500 mm. Structure parameters for different wall thickness and moulding materials (graphite nodule count, ferrite and cementite fraction are plotted versus distance from the beginning of spiral. It is shown strong influence of LDASC sand (material with small ability to absorb heat on structure parameters (NF, Vf i VC revealing gradient character of TWDI.

  5. In-situ surface hardening of cast iron by surface layer metallurgy

    International Nuclear Information System (INIS)

    Abrasive wear is a serious problem in many cast iron castings used in industry. To minimize failure and repair of these components, different strategies exist to improve their surface microhardness thus enhancing their wear resistance. However, most of these methods lead to very brittle and/or expensive castings. In the current work a new method for surface hardening is presented which utilizes surface layer metallurgy to generate in-situ a boron-enriched white cast iron surface layer with a high microhardness on a gray cast iron casting. To do this, sand molds are coated with a ferroboron suspension and cast with a cast iron melt. After solidification, a 100–900 µm thick layer of boron-enriched ledeburite is formed on the surface of the casting which produces an increase in the average microhardness from 284 HV0.1±52 HV0.1 to 505 HV0.1±87 HV0.1. Analyses of the samples' core reveal a typical cast iron microstructure which leads to the conclusion that the coating mainly affects the castings' surface. By varying the grain size of the ferroboron powder in the coatings, it is shown that a powder size ≤100 µm is most suitable to create a boron-enriched ledeburite surface layer possessing high hardness values

  6. Effect of titanium on the as-cast microstructure and impact toughness of hypereutectic high-chromium cast iron

    Energy Technology Data Exchange (ETDEWEB)

    Huang, Zhifu; Xing, Jiandong; Gao, Yimin; Zhi, Xiaohui [Xi' an Jiaotong Univ., Xi' an (China). State Key Lab. for Mechanical Behavior of Materials

    2012-05-15

    The effect of titanium on the as-cast microstructure of a hypereutectic high-chromium cast iron was investigated by means of optical microscopy, scanning electron microscopy and energy-dispersive X-ray spectroscopy. The results indicate that the primary M{sub 7}C{sub 3} carbides are refined and spheroidized with the addition of a suitable amount of titanium. TiC is found in the primary carbide by energy dispersive spectroscopy analysis. The mechanism of titanium modification on the microstructure of the alloy is also discussed. In addition, the impact test result indicates that, compared with the hypereutectic high-chromium cast iron without titanium addition, the impact toughness value of hypereutectic high-chromium cast iron with titanium additions is improved and approximately reaches 6.4 J . cm{sup -2}. (orig.)

  7. Microstructure and Property of Hypereutectic High Chromium Cast Iron Prepared by Slope Cooling Body-Centrifugal Casting Method

    Institute of Scientific and Technical Information of China (English)

    Zhifu HUANG; Jiandong XING; Anfeng ZHANG

    2006-01-01

    In this paper, the ring-type ingot of hypereutectic high Cr cast iron was obtained by slope cooling bodycentrifugal casting method (SC-CCM), and its microstructure and impact toughness were investigated, respectively. The results indicated that, first, the primary carbides in the microstructure are prominently finer than those in the hypereutectic high Cr cast iron prepared by conventional casting method. Second, in the ring-type ingot, the primary carbides near radial outer field are finer than those near radial inner field; furthermore, there is dividing field in the microstructure. Finally, the impact toughness values of the specimens impacted on the radial outer face and on the radial inner face are improved respectively about 36% and 138%more than that of the hypereutectic high Cr one prepared by conventional casting method.

  8. The role of graphite morphology and matrix structure on low frequency thermal cycling of cast irons

    Indian Academy of Sciences (India)

    S Y Buni; N Raman; S Seshan

    2004-02-01

    Low frequency thermal cycling tests were carried out on four types of cast iron (viz., austempered ductile iron, pearlitic ductile iron, compacted/vermicular graphite iron and grey cast iron) at predetermined ranges of thermal cycling temperatures. The specimens were unconstrained. Results show that austempered ductile iron has the highest thermal cycling resistance, followed by pearlitic ductile iron and compacted graphite iron, while grey cast iron exhibits the lowest resistance. Microstructural analysis of test specimens subjected to thermal cycling indicates that matrix decomposition and grain growth are responsible for the reduction in hardness while graphite oxidation, de-cohesion and grain boundary separation are responsible for the reduction in the modulus of elasticity upon thermal cycling.

  9. Modelling the solidification of ductile cast iron parts with varying wall thicknesses

    DEFF Research Database (Denmark)

    Bjerre, Mathias Karsten; Tiedje, Niels Skat; Thorborg, Jesper;

    2015-01-01

    a 2D FE solution of the heat conduction equation is developed in an in-house code and model parameters are calibrated using experimental data from representative castings made of ductile cast iron. The main focus is on the influence of casting thickness and resulting local cooling conditions on the...

  10. 77 FR 17119 - Pipeline Safety: Cast Iron Pipe (Supplementary Advisory Bulletin)

    Science.gov (United States)

    2012-03-23

    ... Pipeline and Hazardous Materials Safety Administration Pipeline Safety: Cast Iron Pipe (Supplementary...; October 11, 1991 and ALN-92-02; June 26, 1992) covering the continued use of cast iron pipe in natural gas... INFORMATION CONTACT: Jeff Gilliam, Director, Engineering and Research, 202-366-0568 or by email at...

  11. Influences on Burr Size During Face-Milling of Aluminum Alloys and Cast Iron

    OpenAIRE

    Shefelbine, Wendy; Dornfeld, David

    2004-01-01

    The Exit Order Sequence (EOS) theory discussed by previous LMA students predicts the size of burrs formed during face milling. Other influences are tool geometry, coolant use, and material properties in aluminum silicon alloys and cast iron. Used, worn tools also increase the size of the burr. The effect of speed and feed are also discussed, particularly with regards to cast iron.

  12. Impact toughness and microstructure of continuous medium carbon steel bar-reinforced cast iron composite

    International Nuclear Information System (INIS)

    Although nodular cast iron has popular characteristics, its toughness and tensile strength are insufficient in many applications. In the present research, an attempt was made to produce a nodular cast iron composite reinforced with medium carbon steel bar, in order to investigate its effects on improving the toughness of the material. The composite material was produced by the sand mould casting technique. Then, the samples were annealed at 900 °C for 1 h. Afterwards, the microstructures of the composite in as cast and annealed conditions were analyzed by optical and electron microscopes. Later on, the hardness and impact toughness of the cast iron composite specimens were compared with the samples without reinforcement. The results revealed a pearlitic diffusion bond between the two components of the composite, due to the diffusion of carbon from the cast iron towards the steel bar. Furthermore, the impact toughness of the composite material showed better results in comparison with that of the simple specimens.

  13. Cast iron with spherical graphite is a perspective material for NPP equipment manufacture

    International Nuclear Information System (INIS)

    High-plasticity austenitic and ferritic spheroidal graphite cast irons are designed. The ferritic spheroidal graphite cast iron is shown to have a high fracture toughness after additional recrystallization heat treatment. The nodular cast iron is noted to show promise for components operating under irradiation. Domestic experience of production of ferritic and austenitic nodular cast irons of high fracture toughness permits to cast any complex-shaped components. This fact in combination with good workability gives the possibility of decreasing the number of labour consuming operations in manufacturing as spent fuel storage and shipping casks so other components of NPPs. The nodular irons are recommended to be used instead of steel 00Kh13NDP and 0Kh18N9T forgings

  14. Influence of spheroidal cast iron wall thickness on its microstructure and ultrasonic control index

    OpenAIRE

    W. Orłowicz; M. Tupaj; M. Mróz; E. Guzik; E. Gierut; W. Pilut; A. Zimowski

    2009-01-01

    This work presents results of ultrasonic evaluation of the microstructure of spheroidal cast iron manufactured under production conditions.Evaluation of the ultrasonic control index’s sensitiveness to changes in microstructure (graphite shape index Ss and average number of graphite precipitations NA) of cast iron, was made on modelled stepped castings. A relation between the graphite precipitation shape index Ss and the velocity of longitudinal ultrasonic wave cL has been defined, as well as ...

  15. Development of a manufacturing technology of compacted graphite iron castings from a cupola furnace

    Directory of Open Access Journals (Sweden)

    O. Bouska

    2012-01-01

    Full Text Available Compacted graphite iron, also known as vermicular cast iron or semiductile cast iron is a modern material, the production of which is increasing globaly. Recently this material has been very often used in automotive industry. This paper reviews some findigs gained during the development of the manufacturing technology of compacted graphite iron under the conditions in Slévárna Heunisch Brno, Ltd. The new technology assumes usage of cupola furnace for melting and is beeing developed for production of castings weighing up to 300 kilograms poured into bentonite sand moulds.

  16. Correlation Between Surface Roughness and Rheological Properties of Liquid Ductile Cast Iron

    Directory of Open Access Journals (Sweden)

    B. Borowiecki

    2012-12-01

    Full Text Available The investigation of filling process of ductile cast iron flow in sand mould was showed the correlation between casting roughness surface and rheological properties of metal. Evidently of castings surface roughness was state of distance, from a few to a dozen diameters of vertical channel inlet. The method of rod fluidity test permit to study of rheological properties of metal and the roughness surface of castings.

  17. Initial assessment of effectiveness of some selected inoculants for grey cast iron

    Directory of Open Access Journals (Sweden)

    M. S. Soiński

    2010-04-01

    Full Text Available The influence of four inoculants: FeSi75, Zircinoc, Foundry Grade, and Inogen has been determined in the work. The additions have been introduced in the amount of 0,2% into the cast iron exibiting the degree of saturation SC = 0,824. The shape, the size, and the arrangement of graphite precipitates have been determined, as well as the cast iron matrix type; both the initial cast iron and the modified alloy have been examined, the latter cast after either 2 or 8 minutes after the inoculation treatment. Additionally the chilling tendency of the cast iron has been assessed, the number of eutectic cells has been determined, and mechanical properties (strength and hardness of the alloy have been examined. It has been found that each of the inoculants significantly lowers the cast iron chilling tendency, however not to the same degree. Additionally, the graphite arrangement is changed from interdendritic one present in the initial cast iron to the arrangement of prevailing A type revealed in the modified alloy. The inoculation treatment leads to the distinct growth in the number of eutectic cells and to the increasing of cast iron tensile strength, the latter however not to the large extent.

  18. Fiber laser cladding of nickel-based alloy on cast iron

    Science.gov (United States)

    Arias-González, F.; del Val, J.; Comesaña, R.; Penide, J.; Lusquiños, F.; Quintero, F.; Riveiro, A.; Boutinguiza, M.; Pou, J.

    2016-06-01

    Gray cast iron is a ferrous alloy characterized by a carbon-rich phase in form of lamellar graphite in an iron matrix while ductile cast iron presents a carbon-rich phase in form of spheroidal graphite. Graphite presents a higher laser beam absorption than iron matrix and its morphology has also a strong influence on thermal conductivity of the material. The laser cladding process of cast iron is complicated by its heterogeneous microstructure which generates non-homogeneous thermal fields. In this research work, a comparison between different types of cast iron substrates (with different graphite morphology) has been carried out to analyze its impact on the process results. A fiber laser was used to generate a NiCrBSi coating over flat substrates of gray cast iron (EN-GJL-250) and nodular cast iron (EN-GJS-400-15). The relationship between processing parameters (laser irradiance and scanning speed) and geometry of a single laser track was examined. Moreover, microstructure and composition were studied by Scanning Electron Microscopy (SEM), Energy Dispersive X-Ray Spectroscopy (EDS) and X-Ray Diffraction (XRD). The hardness and elastic modulus were analyzed by means of micro- and nanoindentation. A hardfacing coating was generated by fiber laser cladding. Suitable processing parameters to generate the Ni-based alloy coating were determined. For the same processing parameters, gray cast iron samples present higher dilution than cast iron samples. The elastic modulus is similar for the coating and the substrate, while the Ni-based coating obtained presents a significantly superior hardness than cast iron.

  19. 75 FR 54595 - Certain Iron Construction Castings From Brazil, Canada, and the People's Republic of China: Final...

    Science.gov (United States)

    2010-09-08

    ... From Canada, 51 FR 7600 (March 5, 1986), Antidumping Duty Order; Iron Construction Castings From Brazil, 51 FR 17220 (May 9, 1986), and Antidumping Duty Order; Iron Construction Castings From the People's... International Trade Administration Certain Iron Construction Castings From Brazil, Canada, and the...

  20. RESEARCH OF INFLUENCE OF LIQUID ALUMINUM ON RESISTANCE OF THE STEEL AND CAST-IRON TOOL

    OpenAIRE

    S. S. Zhizhchenko; I. A. Shpareva; M. A. Turchanin; P. G. Agraval

    2015-01-01

    The study of the interaction of steel and cast iron with aluminum was performed by immersion, and isothermal holding. By optical and electron microscopy, the microstructure of the reaction zone was investigated. The partial enthalpy of dissolution of iron, steel and cast iron in liquid aluminum has been investigated by high-temperature calorimetry at 1773 K. X-ray analysis and microhardness measurements was used to study the phase composition of the reaction zone. The thermodynamic descriptio...

  1. Obtaining Martensitic Structures during Thixoforming of Hypoeutectic Gray Cast Iron

    Directory of Open Access Journals (Sweden)

    Lucas Bertolino Ragazzo

    2015-01-01

    Full Text Available The control of parameters such as liquid fraction, holding time, and cooling rate during thixoforming can help control the final microstructure of the thixoformed part, thus improving its mechanical properties. This study intended to investigate conditions required to obtain martensite in hypoeutectic gray cast iron at 3.1% CE (carbon equivalent deformed in the semisolid state. Samples heated up to 1130, 1135, and 1145°C (liquid fractions of 10, 30, and 45% were compressed into platens without any holding time (0 s. If a sample presented a martensitic structure for 0 s holding time, new samples were retested at the same temperature for 30, 60, and 90 s holding times. The die casting process was simulated by allowing the platens to become locked after hot compression. Samples that cooled in the locked platens were submitted to higher cooling rates than samples that cooled with the platens open and presented martensite instead of the conventional ferrite and pearlite. Thus, the factor that had the greatest influence on the formation of martensite was the cooling rate rather than stress. The thixoforming process presented good morphological stability, which is highly desirable for industrial applications.

  2. Chromium and copper influence on the nodular cast iron with carbides microstructure

    Directory of Open Access Journals (Sweden)

    G. Gumienny

    2010-10-01

    Full Text Available In this paper chromium to 1,00% and copper to 1,50% influence at constant molybdenum content of about 1,50% on the nodular cast ironwith carbides microstructure has been presented. It was found, that as a result of synergic addition of above-mentioned elements there isthe possibility obtaining an ausferrite in nodular cast iron with carbides castings. Conditions have been given, when in nodular cast iron with carbides at cooling at first in the form, then air-cooling austenite transformation to upper bainite, its mixture with lower bainite, martensite or ausferrite takes place. Transformations proceed during cooling and the crystallization of cast iron have been determined and the casting hardness has been presented.

  3. CHANGE OF CONNECTION BETWEEN MAGNETIC PARAMETERS OF CAST IRON IN COMPARISON WITH STEEL UNDER INFLUENCE OF INTERNAL DEMAGNETIZATION

    Directory of Open Access Journals (Sweden)

    S. G. Sandomirsky

    2014-01-01

    Full Text Available Connection of maximum magnetic permeability µm of cast irons with coercive force Нс and residual magnetism Мr is established in all size of changing of the magnetic characteristics of cast iron. Differences of this connection for steels and cast irons are revealed. Formula for calculation µm of steels by Нс and Мr is corrected for calculation µm of cast irons. As a result of correction the calculation error of cast irons µm is diminished. The results can be used in magnetic structural analysis instead of labor-consuming measurement µm.

  4. INVESTIGATION OF EFFICIENCY OF GRAY CAST IRON GRAPHITIZING MODIFICATION BY DISPERSION-FILLED CONSUMABLE PATTERN

    Directory of Open Access Journals (Sweden)

    I. A. Nebozhak

    2016-01-01

    Full Text Available The key criteria of the process of graphitizing modification of matrix melt silicon concentration and silicon assimilation evaluated were on samples of gray cast iron grade СЧ20 State Standard 1412-85. These criteria of evaluation on the structure and properties of casting ingots proved an efficiency of intra-mold modification of molten gray cast iron by dispersed ferrosilicon grade ФС75 State Standard 1415-93 (ISO 5445-80 using lost-foam casting (LFC-process.

  5. Analysis of reasons causing riser feeding failure in nodular iron castings production

    Directory of Open Access Journals (Sweden)

    ZHOU Gen

    2005-11-01

    Full Text Available In addition to mold rigidity and metallurgical quality of iron melting, the main reasons causing riser feeding failure in nodular iron castings production are: (a open and cold metal flowing-over risers were adopted; (b riser location was not proper; (c riser was too small or/and not enough high; (d ingates did not freeze up instantly as soon as pouring finished;(e there're isolated hot spots in the casting which are not connected with feeding channel of the riser; (f the feeding channel of castings with small size and thin sections is too narrow for feeding liquid to enter casting; and so on.

  6. Effect of Manganese on As-Cast Microstructure and Hardening Behavior of High Chromium White Cast Iron

    Institute of Scientific and Technical Information of China (English)

    SUN Zhi-ping; SHEN Bao-luo; WANG Jun; LIU Hao-huai; LUO Cheng

    2005-01-01

    The effect of manganese on the as-cast structure and hardening behavior of high chromium white cast iron subjected to sub-critical treatment was studied. The results indicate that the fraction of retained austenite and the manganese distribution in as-cast alloys are controlled by manganese content. The manganese distribution in as-cast alloys is not homogeneous. The manganese content in carbide is higher than that in matrix. Whether the secondary hardening occurs or not and the peak hardness of secondary hardening is controlled by manganese content in retained austenite in as-cast structure. Higher manganese content can cause more retained austenite. The secondary hardening occurs in sub-critical treating process if the fraction of retained austenite is high.

  7. TDA method application to austenite transformation in nodular cast iron with carbides assessment

    OpenAIRE

    G. Gumienny

    2011-01-01

    In this paper the possibility of TDA method using to austenite transformation in nodular cast iron with carbides assessment is presented. Studies were conducted on cast iron with about 2% molybdenum and 0,70% to 4,50% nickel. On diagrams, where TDA curves are pre- sented, on time axis a logarithmic scale was applied. It has not been used up to now. It was found, that during cooling and crystallization of cast iron in TDA probe, on the derivative curve there is a slight thermal effect from aus...

  8. Role of Titanium in Thin Wall Vermicular Graphite Iron Castings Production

    Directory of Open Access Journals (Sweden)

    M. Górny

    2013-04-01

    Full Text Available In this paper the effects of titanium addition in an amount up to 0.13 wt.% have been investigated to determine their effect on the microstructure and mechanical properties of Thin Wall Vermicular Graphite Iron Castings (TWVGI. The study was performed for thinwalled iron castings with 3-5 mm wall thickness and for the reference casting with 13 mm. Microstructural changes were evaluated by analyzing quantitative data sets obtained by image analyzer and also using scanning electron microscope (SEM. Metallographic examinations show that in thin-walled castings there is a significant impact of titanium addition to vermicular graphite formation. Thinwalled castings with vermicular graphite have a homogeneous structure, free of chills, and good mechanical properties. It may predispose them as a potential use as substitutes for aluminum alloy castings in diverse applications.

  9. Effect of molybdenum, vanadium, boron on mechanical properties of high chromium white cast iron in as-cast condition

    Science.gov (United States)

    Nurjaman, F.; Sumardi, S.; Shofi, A.; Aryati, M.; Suharno, B.

    2016-02-01

    In this experiment, the effect of the addition carbide forming elements on high chromium white cast iron, such as molybdenum, vanadium and boron on its mechanical properties and microstructure was investigated. The high chromium white cast iron was produced by casting process and formed in 50 mm size of grinding balls with several compositions. Characterization of these grinding balls was conducted by using some testing methods, such as: chemical and microstructure analysis, hardness, and impact test. From the results, the addition of molybdenum, vanadium, and boron on high chromium white cast iron provided a significant improvement on its hardness, but reduced its toughness. Molybdenum induced fully austenitic matrix and Mo2C formation among eutectic M7C3 carbide. Vanadium was dissolved in the matrix and carbide. While boron was played a role to form fine eutectic carbide. Grinding balls with 1.89 C-13.1 Cr-1.32 Mo-1.36 V-0.00051 B in as-cast condition had the highest hardness, which was caused by finer structure of eutectic carbide, needle like structure (upper bainite) matrix, and martensite on its carbide boundary.

  10. COMPARATIVE RESEARCHES OF FRACTURES OF HIGH-STRENGTH CAST IRON IN THE AS-CAST AND DEFORMED STATE

    Directory of Open Access Journals (Sweden)

    A. I. Pokrovsky

    2016-01-01

    Full Text Available The results of comparative studies of fracture surfaces of high-strength cast iron in the as-cast state and after hot direct extrusion through an aperture of a conical die are presented.The shape change of graphite inclusions and components of the metal matrix is examined with increasing the reduction ratio from 0 (as-cast state to 80%.For the fist time, using the electrochemical etching of the metal matrix of the cast iron, it is demonstrated experimentally that at plastic deformation the ductile flow of graphite inclusions occurs without fracturing of the latter. The surface morphology of a deformed graphite inclusion is revealed. It is shown that inside the inclusion the strain is distributed non-uniformly: the peripheral zones are deformed to a larger extent while the central part may retain its original radial structure.The fact that the most part of graphite inclusions on the fracture surface of the deformed cast iron appeared undamaged (very small amount of fractured inclusions was observed testifies against the common opinion that graphite acts as a crack nucleation site. A hypothesis is put forward that the crack nucleates in the metal matrix, presumably at the pearlite/ferrite interface, and propagates from one graphite inclusion to another rounding but not damaging the latter.

  11. APPLICATION OF ALLOYED-DIFFUSED CARBONACEOUS WIRE FOR MODIFYING OF CAST IRON

    Directory of Open Access Journals (Sweden)

    V. M. Konstantinov

    2010-01-01

    Full Text Available The process of modifying of cast iron by diffusingalloyed steel wire is studied. The peculiarities of structure formation of diffused layer at thermal-cyclic treatment of wire are established.

  12. TDA method application to austenite transformation in nodular cast iron with carbides assessment

    Directory of Open Access Journals (Sweden)

    G. Gumienny

    2011-07-01

    Full Text Available In this paper the possibility of TDA method using to austenite transformation in nodular cast iron with carbides assessment is presented. Studies were conducted on cast iron with about 2% molybdenum and 0,70% to 4,50% nickel. On diagrams, where TDA curves are pre- sented, on time axis a logarithmic scale was applied. It has not been used up to now. It was found, that during cooling and crystallization of cast iron in TDA probe, on the derivative curve there is a slight thermal effect from austenite to upper bainite or martensite transformation. Depending on nickel concentration austeniteupper bainite transformation start temperature changed (Bus, while MS temperature was independent of it. An influence of nickel on eutectic transformation temperature in nodular cast iron with carbides was determined too.

  13. IMPROVEMENT OF EFFICIENCY OF GREY CAST IRON MODIFICATION DUE TO INTRODUCTION OF CARBON MODIFIER INTO COMPOSITION

    Directory of Open Access Journals (Sweden)

    G. F. Lovshenko

    2016-02-01

    Full Text Available It is shown that introduction carbon into modifier composition and increase of its dispersion degree due to spatter on high-melting particles or due to mechanical alloying increases modifier efficiency for grey cast iron.

  14. Examination of Cast Iron Material Properties by Means of the Nanoindentation Method

    Directory of Open Access Journals (Sweden)

    A. Trytek

    2012-12-01

    Full Text Available The paper presents results of examination of material parameters of cast iron with structure obtained under rapid resolidification conditions carried out by means of the nanoindentation method.

  15. On the weldability of grey cast iron using nickel based filler metal

    International Nuclear Information System (INIS)

    Shielded metal arc welding process using nickel based filler metal was used to join grey cast iron. The effect of post weld heat treatment (PWHT) on the microstructure and hardness was studied. PWHT included heating up to 870 oC, holding for 1 h at 870 oC and then furnace cooling. By using nickel based filler metal, formation of hard brittle phase (e.g. carbides and martensite) in the fusion zone is prevented. Before PWHT, heat affected zone exhibited martensitic structure and partially melted zone exhibited white cast iron structure plus martensite. Applied PWHT resulted in the dissolution of martensite in heat affected zone and graphitization and in turn the reduction of partially melted zone hardness. Results showed that welding of grey cast iron with nickel based filler metal and applying PWHT can serve as a solution for cast iron welding problems.

  16. Numerical modelling of thin-walled hypereutectic ductile cast iron parts

    DEFF Research Database (Denmark)

    Pedersen, Karl Martin; Hattel, Jesper Henri; Tiedje, Niels Skat

    2006-01-01

    Solidification of hypereutectic thin-walled ductile cast iron has been modelled in one dimension taking into account the precipitation of off-eutectic austenite dendrites during solidification. The simulations have been compared with casting experiments on plate geometries with plate thicknesses...

  17. A new type of antifriction and wear resistant malleable cast iron

    Science.gov (United States)

    Davidov, S. V.; Gorlenko, A. O.

    2016-04-01

    There is developed a technology of malleable cast iron modification on the basis of complex chemical compound of surface-active elements and their solid solutions with other elements. Silicon high content in malleable cast iron helped to develop a power efficient technology of graphitizing annealing which has considerably lower annealing temperature and complete renunciation of the second graphitizing annealing stage at the expense of its change by controlled cooling up to ferrite structure or by air cooling for perlite structure.

  18. Assessment of ductile iron casting process with the use of the DRSA method

    OpenAIRE

    Kujawińska A.; Rogalewicz M.; Diering M.; Piłacińska M.; Hamrol A.; Kochańskib A.

    2016-01-01

    The paper introduces a concept of assessment of a ductile iron casting process with use of the rule-based approach, known as DRSA (dominance-based rough set approach). The research was conducted in a large Polish foundry. The collected data concern the chemical composition and mechanical properties of the used ductile cast iron. In the paper, a methodology of creating a rule-based moulding model for the tensile strength was proposed. The quality, sensitivit...

  19. Influence of selected modifiers on crystallization curve of chromium cast iron

    Directory of Open Access Journals (Sweden)

    A. Studnicki

    2009-07-01

    Full Text Available In article was introduced the results of investigations of modified chromium cast iron crystallization process. It the cast iron about composition of basic elements C = 2,8 % and Cr = 18% was modified with five substances (boron carbide, ferrosilicon, ferrocalciumsilicon, ferroniobium and ferroniobium with ferrovanadium. Influence on course of primary and secondary crystallization process was observed. The investigations of crystallization was conducted DTA method in tester DTA - C.

  20. Undercooling and nodule count in thin walled ductile iron castings

    OpenAIRE

    Pedersen, Karl Martin; Tiedje, Niels Skat

    2007-01-01

    Casting experiments have been performed with eutectic and hypereutectic castings with plate thicknesses from 2 to 8 mm involving both temperature measurements during solidification and microstructural examination afterwards. The nodule count was the same for the eutectic and hypereutectic castings in the thin plates (≤4.3 mm) while in the 8 mm plate the nodule count was higher in the hypereutectic than in the eutectic castings. The minimum temperature before the eutectic recalescence (Tmin) w...

  1. Cast iron deterioration with time in various aqueous salt solutions

    Indian Academy of Sciences (India)

    Rita Mehra; Aditi Soni

    2002-02-01

    The changes with time in the corrosion rate and corrosion current density on a cast iron electrode in various aqueous salt solutions have been carried out using total immersion test and potentiostatic polarization curves. The concentration of salts taken is expected to be present in potable water. The relative behaviour of these salts towards corrosion has also been studied, which is found to be different from previous studies. The total immersion test parameters viz. weight loss, corrosion rate as well as potentiostatic parameters, open circuit potential, corr, Tafel slopes, corrosion rate, have been calculated by standard methods. Besides these the relative increase in corrosion rate with time as well as the percentage to which corrosion rate should be decreased so as to provide protection towards corrosion have also been calculated. It was found that KCl and NaCl are major contributors than MnSO4, Pb(NO3)2, KI and KBr. The relative increase in corrosion is high in KBr, KI, NaNO3, CaCl2, and less in Pb(NO3)2, NaHCO3 and CaCO3 test solutions. For the reliability of results the data has been statistically analysed.

  2. Pearlitic ductile cast iron: damaging micromechanisms at crack tip

    Directory of Open Access Journals (Sweden)

    F. Iacoviello

    2013-07-01

    Full Text Available Ductile cast irons (DCIs are characterized by a wide range of mechanical properties, mainly depending on microstructural factors, as matrix microstructure (characterized by phases volume fraction, grains size and grain distribution, graphite nodules (characterized by size, shape, density and distribution and defects presence (e.g., porosity, inclusions, etc.. Versatility and higher performances at lower cost if compared to steels with analogous performances are the main DCIs advantages. In the last years, the role played by graphite nodules was deeply investigated by means of tensile and fatigue tests, performing scanning electron microscope (SEM observations of specimens lateral surfaces during the tests (“in situ” tests and identifying different damaging micromechanisms.In this work, a pearlitic DCIs fatigue resistance is investigated considering both fatigue crack propagation (by means of Compact Type specimens and according to ASTM E399 standard and overload effects, focusing the interaction between the crack and the investigated DCI microstructure (pearlitic matrix and graphite nodules. On the basis of experimental results, and considering loading conditions and damaging micromechanisms, the applicability of ASTM E399 standard on the characterization of fatigue crack propagation resistance in ferritic DCIs is critically analyzed, mainly focusing the stress intensity factor amplitude role.

  3. Energy Saving Melting and Revert Reduction Technology: Aging of Graphitic Cast Irons and Machinability

    Energy Technology Data Exchange (ETDEWEB)

    Richards, Von L. [Advanced Technology Inst., Virginia Beach, VA (United States)

    2012-09-19

    The objective of this task was to determine whether ductile iron and compacted graphite iron exhibit age strengthening to a statistically significant extent. Further, this effort identified the mechanism by which gray iron age strengthens and the mechanism by which age-strengthening improves the machinability of gray cast iron. These results were then used to determine whether age strengthening improves the machinability of ductile iron and compacted graphite iron alloys in order to develop a predictive model of alloy factor effects on age strengthening. The results of this work will lead to reduced section sizes, and corresponding weight and energy savings. Improved machinability will reduce scrap and enhance casting marketability. Technical Conclusions: Age strengthening was demonstrated to occur in gray iron ductile iron and compacted graphite iron. Machinability was demonstrated to be improved by age strengthening when free ferrite was present in the microstructure, but not in a fully pearlitic microstructure. Age strengthening only occurs when there is residual nitrogen in solid solution in the Ferrite, whether the ferrite is free ferrite or the ferrite lamellae within pearlite. Age strengthening can be accelerated by Mn at about 0.5% in excess of the Mn/S balance Estimated energy savings over ten years is 13.05 trillion BTU, based primarily on yield improvement and size reduction of castings for equivalent service. Also it is estimated that the heavy truck end use of lighter castings for equivalent service requirement will result in a diesel fuel energy savings of 131 trillion BTU over ten years.

  4. Undercooling and nodule count in thin walled ductile iron castings

    DEFF Research Database (Denmark)

    Pedersen, Karl Martin; Tiedje, Niels Skat

    2007-01-01

    Casting experiments have been performed with eutectic and hypereutectic castings with plate thick¬nesses from 2 to 8 mm involving both temperature measurements during solidification and micro¬structural examination afterwards. The nodule count was the same for the eutectic and hypereutectic...... castings in the thin plates ( 4.3 mm) while in the 8 mm plate the nodule count was higher in the hypereutectic than in the eutectic castings. The minimum temperature prior to the eutectic recalescence (Tmin) was 15 to 20C lower for the eutectic than the hypereutectic castings. This is due to nucleation...... of graphite nodules which begins at a lover temperature in the eutectic than in the hypereutectic castings The recalescence (Trec) was however also larger for the eutectic casting and in the thin plates the maximum temperature after recalescence (Tmax) was the same in the eutectic and hypereutectic...

  5. Undercooling and nodule count in thin walled ductile iron castings

    DEFF Research Database (Denmark)

    Pedersen, Karl Martin; Tiedje, Niels Skat

    2007-01-01

    Casting experiments have been performed with eutectic and hypereutectic castings with plate thicknesses from 2 to 8 mm involving both temperature measurements during solidification and microstructural examination afterwards. The nodule count was the same for the eutectic and hypereutectic castings...... in the thin plates (≤4.3 mm) while in the 8 mm plate the nodule count was higher in the hypereutectic than in the eutectic castings. The minimum temperature before the eutectic recalescence (Tmin) was 15 to 20ºC lower for the eutectic than for the hypereutectic castings. This is due to nucleation of...... graphite nodules which begins at a lower temperature in the eutectic than in the hypereutectic castings. The recalescence ∆Trec was however also larger for the eutectic casting and in the thin plates the maximum temperature after recalescence (Tmax) was the same in the eutectic and hypereutectic plates...

  6. Investigation of solidification of thin walled ductile cast iron using temperature measurement

    DEFF Research Database (Denmark)

    Pedersen, Karl Martin; Tiedje, Niels

    2005-01-01

    Investigation of solidification of thin walled ductile cast iron can be improved using temperature measurement. This article includes some background of the precautions that have to be taken when measuring temperatures in thin walled castings. The aim is to minimize influence of temperature...... measurement on castings and to get sufficient response time of thermocouples. Investigation of thin wall ductile iron has been performed with temperature measurement in plates with thickness between 2,8 and 8mm. The cooling curves achieved are combined with examination of the microstructure in order to reveal...

  7. The Influence of Small Amounts of Aluminium on the Effectiveness of Cast Iron Spheroidization with Magnesium

    OpenAIRE

    M. S. Soiński; A. Jakubus

    2013-01-01

    The influence of aluminium added in amounts of about 1.6%, 2.1%, or 2.8% on the effectiveness of cast iron spheroidization with magnesium was determined. The cast iron was melted and treated with FeSiMg7 master alloy under industrial conditions. The metallographic examinations were performed for the separately cast rods of 20 mm diameter. They included the assessment of the shape of graphite precipitates and of the matrix structure. The results allowed to state that the despheroidizing influe...

  8. THE INFLUENCE OF CHEMICAL COMPOSITION OF HIGH-CHROMIUM CAST IRONS ON THE MACHINABILITY

    Directory of Open Access Journals (Sweden)

    V. V. Netrebko

    2016-02-01

    Full Text Available Purpose. This research is aimed to obtain the regression dependence of the machinability on the chemical composition of pig iron (C, Cr, Mn and Ni in cast state. Methodology. The method of active experiment planning was used to build a mathematical model. Cast irons of composition 1.09…3.91 % С; 11.43…25.57 % Cr; 0.6…5.4 % Mn; 0.19…3.01 % Ni were studied. Cutting tools with plates 10х10 mm out of ВК8 according to State Standard 19051-80 were used for turning. Cutting modes: cutting depth – 0.8 mm, longitudinal feed – 0.15 mm/rot., spindle’s rotation frequency during turning – 200…360 rot./min. Lubricating and cooling liquids were not applied. Evaluation of iron workability was produced by determining the linear tool flank wear per unit length of the cutting path. Findings. Mathematically probabilistic equation of the regression dependence of the cutting tool’s wear on the C, Cr, Mn and Ni content in the machined cast iron were obtained. It was established that with the increase of Cr content in the cast iron to 14.8 % the cutting tool’s wear decreased as a result of formation of carbide eutectic which destroyed the doped ledeburite continuous frame. Further increase of chromium content promoted appearing of chromic carbides with high microhardness which considerably increased the tool’s wear. The conducted research shown that the minimum cutting tool’s wear 0,18 mkm/m was observed during the machining of cast iron containing: 1.09 % C, 14.8 % Cr, 2.3 % Mn and 1.2 % Ni; and the maximum wear is 48,96 mkm/m – when the content was: 3.91 % C, 11.43 % Cr, 5.4 % Mn and 0.19 % Ni. The tool’s wear reached 47.61 mkm/m during the treatment of cast iron containing 3.91 % C, 25.57 % Cr, 5.4 % Mn and 0.19 % Ni. Originality. Mathematically probabilistic model of the dependence of the cutting tool’s wear on the C, Cr, Mn and Ni content in the machined cast iron has been elaborated by the author. Practical value. The model

  9. Effect of Nb on Structure and Mechanical Properties of Chilled Cast Iron at Room and Elevated Temperatures

    Institute of Scientific and Technical Information of China (English)

    Qijie ZHAI; Li FU; Huaying ZHAI

    2004-01-01

    Effect of Nb on microstructure and mechanical properties of chilled cast iron at room and elevated temperatures is studied in this research. The results demonstrate that the cast structure and mechanical properties of chilled cast iron at room and elevated temperatures are improved with the addition of trace amount of Nb. However, if Nb was added too much, the cast structure and mechanical properties of chilled cast iron would deteriorate. The suitable content of Nb in chilled cast iron is about 0.05% (mass fraction). Except the dissolution in the matrix of cast iron the excessive Nb will form Nb-rich phases in three morphologies. Those are lumpy NbC, complicated strip-like phase and compound with pearlite structure.

  10. Application of 3-D numerical simulation software SRIFCAST to produce ductile iron castings

    Institute of Scientific and Technical Information of China (English)

    2005-01-01

    Based on a method using numerical simulation equations and their solution schemes for liquid metal flows and heat transfer during mold filling and the solidification process of casting, 3-D numerical simulation software SRIFCAST was created. This includes enmeshment of casting; velocity and temperature fields calculation; displaying iso-temperature lines;velocity vectors and 3-D temperature fields on a Windows 9x operating system. SRIFCAST was applied to produce sound castings of automobile and diesel engines, and also to connect with microstructure simulation for ductile iron castings.

  11. Investigation of Bond Strength in Centrifugal Lining of Babbitt on Cast Iron

    Science.gov (United States)

    Diouf, Papa; Jones, Alan

    2010-03-01

    The quality of the bond between Babbitt metal and a cast iron substrate was evaluated for centrifugal casting and static casting using the Chalmers bond strength method and scanning electron microscopy (SEM). The effect of three different centrifugal casting parameters, the speed of revolution, the pouring rate, and the cooling rate, was investigated. The bond strength and the microstructure at the bond interface were predominantly affected by the cooling rate, with a fast cooling rate resulting in better properties. The speed of revolution and the pouring rate only had a small effect on the bond strength, with faster revolution and faster pouring rate resulting in slightly better bonds.

  12. Temperature measurement during solidification of thin wall ductile cast iron. Part 1: Theory and experiment

    DEFF Research Database (Denmark)

    Pedersen, Karl Martin; Tiedje, Niels Skat

    2008-01-01

    Temperature measurement using thermocouples (TC’s) influence solidification of the casting, especially in thin wall castings. The problems regarding acquisition of detailed cooling curves from thin walled castings is discussed. Experiments were conducted where custom made TC’s were used to acquire....... Measurement error depending on TC design and cooling conditions is shown. A method is presented that allows acquisition of cooling curves in thin walled ductile iron castings down to thickness of at least 2.8 mm. The obtained cooling curves can be used to compare nucleation and growth during solidification of...

  13. TO SELECTION OF TECHNOLOGICAL SCHEME OF SOFTENING HEAT TREATMENT FOR HIGH CHROMIUM CAST IRON

    Directory of Open Access Journals (Sweden)

    V. G. Efremenko

    2014-03-01

    Full Text Available Purpose. High chromium cast irons with austenitic matrix have low machinability. The aim of work is search of new energy-saving modes of preliminary softening heat treatment enhancing the machinability of castings by forming an optimum microstructure. Methodology. Metallographic analysis, hardness testing and machinability testing are applied. Findings. It was found out that high temperature annealing with continuous cooling yields to martensite-austenite matrix in cast iron 270Х15Г2Н1MPhT, which abruptly affects the machinability of cast iron. Significant improvement of machinability is achieved by forming of structure "ferrite + granular carbides" and by decline of hardness to 37-39 HRC in the case of two-stage isothermal annealing in the subcritical temperature range or by the use of quenching and tempering (two-step or cyclic. Originality. It was found that the formation of the optimal structure of the matrix and achievement of desired hardness level needed for improving machinability of high chromium cast iron containing 3 % austenite-forming elements, can be obtained: 1 due to pearlite original austenite followed by spherodization eutectoid carbides, and 2 by getting predominantly martensite structure followed by the decay of martensite and carbides coagulation at high-temperature tempering. Practical value. The new energy-saving schemes of softening heat treatment to ensure the growth of machinability of high chromium cast iron, alloyed by higher quantity of austenite forming elements, are proposed.

  14. Stages of vermicular cast iron properties modeling in the intelligent design system

    Science.gov (United States)

    Klochkova, K. V.; Petrovich, S. V.; Simonova, L. A.; Yusupov, L. R.

    2015-06-01

    This article presents the structure of intelligent system of the cast iron with vermicular graphite iron (CGI) design under the conditions of current production, the technique of the optimal process TP parameters of the production of CGI parts in the preparatory phase of production based on mental models is designed.

  15. The sort of carburization and the quality of obtained cast iron

    Directory of Open Access Journals (Sweden)

    K. Janerka

    2008-12-01

    Full Text Available In the production of cast iron, the pig iron’s amount in charge material is more and more often limited, and replaced by steel scrap. That extorts the necessity of know-how the carburization and one is looking for carburizers, which ensure obtaining big carbon increment as quickly as possible with the high repeatability and the ones which ensure getting the adequate quality of cast iron. The object of presented research was definition of the influence of charge materials’ sort on the structure, course of solidification, and the effectiveness of process. The cast iron melts, which are presented below, are made only on the basis of steel scrap with portion of graphitoidal, coke and anthracite carburizers, which were added to the charge in solid. In the article one compared the carburizers in respect of their structure, chemical constitution and the effectiveness obtained during the carburization of liquid metal. The melting of cast iron, based on the special pig iron, was carried out as well. The course of melts, chemical constitution of obtained cast iron and its structure were presented. The comparison between quality distribution and the volume fraction of graphite in classes of size for the individual melts were achieved and the TDA curves were inserted.

  16. Strain analysis on ductile cast iron containers at drop tests

    International Nuclear Information System (INIS)

    Ductile cast iron (DCI) containers for transportation and deposition of radioactive waste have to be designed carefully in order to avoid unacceptable damages and leakages in case of an accident. Therefore various calculations and experimental methods are used during development and licensing of the containers. Besides others the container has to suffer severe impacts (e.g. falling from a height of several meters onto a concrete base). The level of strains must not exceed a value which would adversely affect the package in such a way that it would fail to meet the applicable requirements. In practice complex events such as drop tests are very difficult to calculate. Both the position of maximum stress and the time of its occurrence are not easily predicted with the method of FEM. The uncertainty of the material modelling for plastic deformation by dynamic loading rates is the limiting factor. Therefore holography as an integral measuring technique in combination with strain gauge techniques were used to fit the FEM. By using the FEM calculations in the case of licensing, the FE and the material model have to be verified. The verification of the FEmodel has to be done by comparison of the local maxima measured by strain gauges and by comparison of the vibration modes. These vibration modes we take from holographic measurements. In this paper we explain container vibrations after impact analysed with holographic measurements, FEM calculations and the comparison of the results. The comparison of the local maxima (strain gauges/FEM) is reported elsewhere (Schreiber 1993; Voelzer 1997). (orig.)

  17. Ultrasonic inspection of nodular cast iron insert edge distance using curved linear PA-probe

    International Nuclear Information System (INIS)

    Nuclear fuel disposal canisters consist of a copper tube and a cast iron insert. The copper tube is designed for corrosion protection. The design and use of the nodular cast iron insert is based on strength and fracture mechanic aspects and it is the load carrying part of the structure. The preliminary acceptance criteria for the cast iron insert are under study. There are several aspects in accepting the inspection results of nodular cast iron insert for use. One aspect among others is the position of the edge which is nearest to surface. In an earlier study this was stated to have a tolerance of edge position ± 5 mm. There have been studies both on eccentricity and the real position of the nearest edge tolerances. To determine the edge position, different ultrasonic techniques were tested using a curved linear PA-probe. To evaluate whether the distance variation is within the tolerance limit, the real geometrical nominal distance must be computed. Because the tolerances of the cast iron insert and its internal geometry can give a large variation in the edge position, these must be carefully evaluated. The applied ultrasonic system is a 128 element phased array equipment. The used probe is curved and adjusted to curvature of the cast iron insert. The curved probe was designed to inspect the edge of the channel with one long axial line scanning. During line scanning the phased array probe does at the same time electronical scanning. To optimize this electronic scanning, three different ultrasonic techniques were used. This evaluation of edge distance was tested in four inspections of real size cast iron inserts. It was seen that the variation of the edge position is about 1 to 12 mm in radial direction (straightness) and in circumferential direction about 2 to 8 mm (twist) in range of about 4 m. (orig.)

  18. Characteristics of flake graphite in Ni-Mn-Cu cast iron. Part 2.

    Directory of Open Access Journals (Sweden)

    A. Janus

    2010-01-01

    Full Text Available The paper continues the article published by Archives of Foundry Engineering, vol. 9, issue 1/2009, pp. 185-290, that presented influence of chemical composition of hypo- and hypereutectic nickel-manganese-copper alloyed cast iron on properties of the contained flake graphite. In this second part of the research, effect of chemical composition of hypereutectic cast iron containing 3.5÷5.1% C, 1.7÷2.8% Si, 3.5÷10.5 %Ni, 2.0÷8.0% Mn, 0.1÷3.5% Cu, 0.14÷0.17% P and 0.02÷0.04% S on properties of flake graphite is determined. Evolution of graphite properties with changing eutecticity degree of the examined cast iron is presented. For selected castings, histograms of primary and eutectic graphite are presented, showing quantities of graphite precipitates in individual size ranges and their shape determined by the coefficient ξ defined as ratio of a precipitate area to square of its circumference. Moreover, presented are equations obtained by discriminant analysis to determine chemical composition of Ni-Mn-Cu cast iron which guarantee the most favourable distribution of A-type graphite from the point of view of castings properties.

  19. Effect of vibration frequency on microstructure and performance of high chromium cast iron prepared by lost foam casting

    Directory of Open Access Journals (Sweden)

    Wen-qi Zou

    2016-07-01

    Full Text Available In the present research, high chromium cast irons (HCCIs were prepared using the lost foam casting (LFC process. To improve the wear resistance of the high chromium cast irons (HCCIs, mechanical vibration was employed during the solidification of the HCCIs. The effects of vibration frequency on the microstructure and performance of the HCCIs under as-cast, as-quenched and as-tempered conditions were investigated. The results indicated that the microstructures of the LFC-produced HCCIs were refined due to the introduction of mechanical vibration, and the hardness was improved compared to that of the alloy without vibration. However, only a slight improvement in hardness was found in spite of the increase of vibration frequency. In contrast, the impact toughness of the as-tempered HCCIs increased with an increase in the vibration frequency. In addition, the wear resistance of the HCCIs was improved as a result of the introduction of vibration and increased with an increase in the vibration frequency.

  20. Laser dressing process of porous cast-iron bonded diamond grinding wheels for machining ceramics

    International Nuclear Information System (INIS)

    Dressing using Yttrium Aluminum Garnet-Second Harmonic Generation (YAG-SHG) laser for porous cast-iron bonded diamond grinding wheels is a unique method. Diamond as an abrasive grain shows transparency with the laser, while cast-iron employed as a bonding and bridging material for the present diamond grinding wheels absorbs it. Hence, it is possible for laser to remove cast-iron selectively with a minimal damage on diamond so that dressing can be optimized. In this investigation a newly proposed dressing process using YAG-SHG laser with the wavelength of 532 nm was conducted upon porous cast-iron bonded diamond grinding wheels with fine grains. It revealed that application of laser for dressing evaporates cast-iron and the amount of evaporation increases with laser flux densities, resulting in an increment of protrusion heights. The wheel dressed with laser allows about six times of removal volume rate on ZrO2 at the maximum rather than the same wheel mechanically dressed. It also achieves 90 times less specific grinding energy. With the increase of laser flux density, the removal volume of ground work pieces can be increased or the specific grinding energy decreased. The laser dressed wheels can also achieve the same surface roughness on ground surfaces as mechanically dressed wheels. Copyright (2000) AD-TECH - International Foundation for the Advancement of Technology Ltd

  1. Fabrication of plain carbon steel/high chromium white cast iron bimetal by a liquid-solid composite casting process

    Institute of Scientific and Technical Information of China (English)

    V Javaheri; H Rastegari; M Naseri

    2015-01-01

    High-chromium white cast iron (HCWCI) is one of the most widely used engineering materials in the mining and cement indus-tries. However, in some components, such as the pulverizer plates of ash mills, the poor machinability of HCWCI creates difficulties. The bimetal casting technique is a suitable method for improving the machinability of HCWCI by joining an easily machined layer of plain car-bon steel (PCS) to its hard part. In this study, the possibility of PCS/HCWCI bimetal casting was investigated using sand casting. The inves-tigation was conducted by optical and electron microscopy and non-destructive, impact toughness, and tensile tests. The hardness and chemical composition profiles on both sides of the interface were plotted in this study. The results indicated that a conventional and low-cost casting technique could be a reliable method for producing PCS/HCWCI bimetal. The interfacial microstructure comprised two distinct lay-ers:a very fine, partially spheroidized pearlite layer and a coarse full pearlite layer. Moreover, characterization of the microstructure revealed that the interface was free of defects.

  2. Changes of gas pressure in sand mould during cast iron pouring

    OpenAIRE

    J. Mocek; J. Samsonowicz

    2011-01-01

    The paper presents a test method developed to measure changes of gas pressure in sand moulds during manufacture of iron castings. The pressure and temperature measurements were taken in the sand mould layers directly adjacent to the metal – mould interface. A test stand was described along with the measurement methodology. The sensors used allowed studying the fast-changing nature of the processes which give rise to the gas-originated casting defects. The study examined the influence of binde...

  3. Application of experimental data for numerical simulation of cast iron solidification

    Directory of Open Access Journals (Sweden)

    J. Mendakiewicz

    2008-12-01

    Full Text Available Numerical analysis of cast iron solidification process is presented. The system casting – shell mould is discussed. The parameter controlling the solidification process called a substitute thermal capacity (STC has been constructed in this way in order to take into account the evolution of latent heats connected with the solidification of austenite and eutectic phases. The information concerning the proper approximation of STC results from the experimental data using the thermal and derivative analysis (TDA.

  4. Numerical modelling of thin-walled hypereutectic ductile cast iron parts

    OpenAIRE

    Pedersen, Karl Martin; Hattel, Jesper Henri; Tiedje, Niels Skat

    2006-01-01

    Solidification of hypereutectic thin-walled ductile cast iron has been modelled in one dimension taking into account the precipitation of off-eutectic austenite dendrites during solidification. The simulations have been compared with casting experiments on plate geometries with plate thicknesses from 2.8 to 8.0 mm with good agreement for both cooling curves and nodule counts. The experimental results revealed that the eutectic solidification of plates with thicknesses less than 4.3 mm was cha...

  5. Reliability and Sensitivity Analysis of Cast Iron Water Pipes for Agricultural Food Irrigation

    Directory of Open Access Journals (Sweden)

    Yanling Ni

    2014-07-01

    Full Text Available This study aims to investigate the reliability and sensitivity of cast iron water pipes for agricultural food irrigation. The Monte Carlo simulation method is used for fracture assessment and reliability analysis of cast iron pipes for agricultural food irrigation. Fracture toughness is considered as a limit state function for corrosion affected cast iron pipes. Then the influence of failure mode on the probability of pipe failure has been discussed. Sensitivity analysis also is carried out to show the effect of changing basic parameters on the reliability and life time of the pipe. The analysis results show that the applied methodology can consider different random variables for estimating of life time of the pipe and it can also provide scientific guidance for rehabilitation and maintenance plans for agricultural food irrigation. In addition, the results of the failure and reliability analysis in this study can be useful for designing of more reliable new pipeline systems for agricultural food irrigation.

  6. Assessing the effect of copper additions on the corrosion behaviour of grey cast iron

    Directory of Open Access Journals (Sweden)

    Saliu Ojo SEIDU

    2015-05-01

    Full Text Available In this research work, the effect of copper additions on the corrosion behaviour of grey cast iron in 3.5 wt% NaCl, 0.3M H2SO4, and 0.1M NaOH respectively was investigated. Grey cast iron samples containing 3.0%, 2.5%, 2.0%, and 1.5% weight percent of copper were produced. The corrosion behaviour of the grey cast iron samples produced were assessed using mass loss and corrosion rate measurements according to America Society for Testing and Materials standard (ASTM procedures in salt water, basic, and acidic environments. The results reveal that the samples containing 2.0% and 1.5% weight percent of copper show an excellent corrosion resistance while samples containing 3.0% and 2.5% weight percent of copper show good corrosion behaviour all in salt water and basic environments but poorly in acidic environment.

  7. Removal of arsenate and arsenite from aqueous solution by waste cast iron

    Institute of Scientific and Technical Information of China (English)

    Nag-Choul Choi; Song-Bae Kim; Soon-Oh Kim; Jae-Won Lee; Jun-Boum Park

    2012-01-01

    The removal of As(Ⅲ) and As(Ⅴ) from aqueous solution was investigated using waste cast iron,which is a byproduct of the iron casting process in foundries.Two types of waste cast iron were used in the experiment:grind precipitate dust (GPD) and cast iron shot (CIS).The X-ray diffraction analysis indicated the presence of Fe0 on GPD and CIS.Batch experiments were performed under different concentrations of As(Ⅲ) and As(Ⅴ) and at various initial pH levels.Results showed that waste cast iron was effective in the removal of arsenic.The adsorption isotherm study indicated that the Langmuir isotherm was better than the Freundlich isotherm at describing the experimental result.In the adsorption of both As(Ⅲ) and As(Ⅴ),the adsorption capacity of GPD was greater than CIS,mainly due to the fact that GPD had higher surface area and weight percent of Fe than CIS.Results also indicated the removal of As(Ⅲ) and As(Ⅴ)by GPD and CIS was influenced by the initial solution pH,generally decreasing with increasing pH from 3.0 to 10.5.In addition,both GPD and CIS were more effective at the removal of As(Ⅲ) than As(Ⅴ) under given experimental conditions.This study demonstrates that waste cast iron has potential as a reactive material to treat wastewater and groundwater containing arsenic.

  8. Effect of Feeder Configuration on the Microstructure of Ductile Cast Iron

    DEFF Research Database (Denmark)

    Vedel-Smith, Nikolaj Kjelgaard; Tiedje, Niels Skat

    Feeding and microstructure of a test casting rigged with different feeder combinations was studied. Castings were examined and classified by soundness and microstructure. Subsequently the casting macro- and microstructure was analyzed to study how differences in solidification and segregation...... influence the soundness of different sections of the castings. Moreover, the microstructural changes due to variations in thermal gradients are classified, and the variations in the mushy zone described. The paper discusses how solidification and segregation influence porosity and microstructure of ductile...... iron castings. The goal is to enable metallurgists and foundry engineers to more directly target mushy zone development to prolong the possibility to feed through this section. Keeping smaller section open for an extended period will make it possible to use fewer or smaller feeders, with reduced energy...

  9. Grey cast iron as construction material of bridges from the 18th and 19th century

    Directory of Open Access Journals (Sweden)

    J. Rabiega

    2011-04-01

    Full Text Available Many bridges and railroad viaducts, which have been operated at the western and southern regions of Poland, were erected at the end ofthe 18th or beginning of the 19th century. In recent years they undergo overhauls and renovations requiring familiarity with the construction materials they have been made of. It is necessary for estimation of their load capacity (possible reinforcements and determining their suitability for further utilisation. Among the materials in the old bridges the puddled steels and cast irons predominate. Aim of the work is identification and documentation of microstructure and selected properties of the cast irons used for production of parts for the bridge in Łażany, the Old Mieszczański Bridge in Wrocław, the hanging bridge in Ozimek, as well as the columnar piers of the railroad viaduct in Wrocław. Using the methods of light microscopy and scanning electron microscopy, as well as the results of hardness measurements and chemical analysis, it has been shown that the objects have been built of grey cast iron with flake graphite having the ferritic-pearlitic or pearlitic matrix. The diversification of their chemical analysis resulting from the type, size and geometry of the cast parts was indicated.The tested materials fulfil requirements of the contemporary standards related to grey cast irons of the EN-GJL-100 and EN-GJL-150grades.

  10. Influences of copper on solidification structure and hardening behavior of high chromium cast irons

    Institute of Scientific and Technical Information of China (English)

    WANG Jun; XIONG Ji; FAN Hong-yuan; SHEN Bao-luo; GAO Sheng-ji

    2008-01-01

    The influences of copper on microstructure and the hardening behavior of high chromium cast irons subjected to sub-critical treatment were investigated.The results show that the mierostructure of the as-cast high chromium cast irons consists of retained austenite,martensite and M7 C3 type eutectic carbide.When copper is added into high chromium cast irons,austenite and carbide contents are increased.The increased addition of copper content from 0%to 1.84%leads to the increase of austenite and carbide from 15.9%and 20.0% to 61.0%and 35.5%,respectively.In the process of sub-critical treatment,the retained austenite in the matrix can be precipitated into secondary carbides and then transforms into martensite in cooling process,which causes the secondary hardening of the alloy under sub-critical treatment.High chromium cast irons containing copper in sub-critical treatment appear the second hardening curve peak due to the precipitation of copper from supersaturated matrix.

  11. Graphite nodule count and size distribution in thin-walled ductile cast iron

    DEFF Research Database (Denmark)

    Pedersen, Karl Martin; Tiedje, Niels Skat

    2008-01-01

    Graphite nodule count and size distribution have been analysed in thin walled ductile cast iron. The 2D nodule counts have been converted into 3D nodule count by using Finite Difference Method (FDM). Particles having a diameter smaller than 5 µm should be neglected in the nodule count as these ar...... results. The 3D size distribution showed presence of primary graphite nodules in hypereutectic castings. In thin plates the nodule count is similar in eutectic and hypereutectic plates. In thicker plates the hypereutectic casting has the highest nodule count....

  12. The Influence of Saturation of Cast Iron Austenite with Carbon on the Ausferrite Transformation

    OpenAIRE

    T. Giętka; T. Szykowny; S. Dymski

    2007-01-01

    Austenitizing during quench hardening of the ductile cast iron influences the content of carbon in austenite depending on the soaking heat. On the other hand, the saturation of austenite impacts its transformation in the ausferritizing process of a metal matrix and forming of microstructure. Ductile cast iron with the ferrite matrix was hardened with isothermal transformation in the range of ausferritizing in temperature tpi = 400 i 300 0C and the range of time τpi = 7,5 �� 240 min. Specimens...

  13. Experimental characterization of a Si-Mo-Cr ductile cast iron

    OpenAIRE

    Sesana, Raffaella; Delprete, Cristiana

    2014-01-01

    High temperature-resistant ductile cast irons behaviour is highly interesting for the manufacture of components, such as exhaust manifolds for automotive applications. In the present paper the temperature-dependent static, high cycle and low cycle fatigue behaviour of a heat-resistant Si-Mo-Cr ductile cast iron (Fe-2.4C-4.6Si-0.7Mo-1.2Cr) is investigated. Tensile and high cycle fatigue properties, in terms of elastic modulus, yield stress, elongation at break, fatigue limits, and the stress-l...

  14. Draft ASME code case on ductile cast iron for transport packaging

    International Nuclear Information System (INIS)

    The current Rules for Construction of ''Containment Systems for Storage and Transport Packagings of Spent Nuclear Fuel and High Level Radioactive Material and Waste'' of Division 3 in Section III of ASME Code (2001 Edition) does not include ductile cast iron in its list of materials permitted for use. The Rules specify required fracture toughness values of ferritic steel material for nominal wall thickness 5/8 to 12 inches (16 to 305 mm). New rule for ductile cast iron for transport packaging of which wall thickness is greater than 12 inches (305mm) is required

  15. New Possibilities of Shaping the Surface Properties in Austempered Ductile Iron Castings

    Directory of Open Access Journals (Sweden)

    D. Myszka

    2013-01-01

    Full Text Available The paper presents recent developments concerning the formation of surface layer in austempered ductile iron castings. It was found thatthe traditional methods used to change the properties of the surface layer, i.e. the effect of protective atmosphere during austenitising or shot peening, are not fully satisfactory to meet the demands of commercial applications. Therefore, new ways to shape the surface layer and the surface properties of austempered ductile iron castings are searched for, to mention only detonation spraying, carbonitriding, CVD methods, etc.

  16. Laser powder surfacing of the Si-Mo spheroidal cast iron with nickel powder

    OpenAIRE

    Klimpel, A; L.A. Dobrzański

    2006-01-01

    Purpose: Investigation results are presented of the effect of main parameters of laser powder surfacing of the Si-Mo spheroidal cast iron with the nickel based powder on quality and shape of padding welds and portion of the substrate material in the padding weld.Design/methodology/approach: It was shown basing on investigation of the process of laser powder surfacing with the nickel based powder onto the spheroidal cast iron substrate that it is feasible to make high quality padding welds in ...

  17. Assessment of ductile iron casting process with the use of the DRSA method

    Directory of Open Access Journals (Sweden)

    Kujawińska A.

    2016-01-01

    Full Text Available The paper introduces a concept of assessment of a ductile iron casting process with use of the rule-based approach, known as DRSA (dominance-based rough set approach. The research was conducted in a large Polish foundry. The collected data concern the chemical composition and mechanical properties of the used ductile cast iron. In the paper, a methodology of creating a rule-based moulding model for the tensile strength was proposed. The quality, sensitivity and accuracy of the model extracted from the data were examined. The studies proved its usefulness in the industrial practice and for aiding of the decision making process.

  18. Effect of boron carbide on primary crystallization of chromium cast iron

    Directory of Open Access Journals (Sweden)

    A. Studnicki

    2008-04-01

    Full Text Available In the paper results of the influence of boron carbide (B4C as inoculant of abrasion-resisting chromium cast iron (about 2,8% carbon and 18% chromium on primary crystallization researches are presented. Boron carbide dispersion was introduced at the bottom of pouring ladle before tap of liquid cast iron. In this investigations were used three different quantities of inoculant in amounts 0,1%; 0,2% and 0,3% with relation to bath weight. It has been demonstrated that such small additions of boron carbide change primary crystallization parameters, particularly temperature characteristic of process, their time and kinetics.

  19. Stress triaxiality influence on damaging micromechanisms in a pearlitic ductile cast iron

    Directory of Open Access Journals (Sweden)

    Vittorio Di Cocco

    2014-10-01

    Full Text Available In the last decades, damaging micromechanisms in ductile cast irons (DCIs have been widely investigated, considering both the matrix microstructure and the loading conditions influence. Considering the graphite nodules, they were initially considered as voids embedded and growing in a ductile metal matrix (especially considering ferritic ductile cast irons. Recent experimental results allowed to identify a more complex role played by the graphite nodules, depending on the matrix microstructure. In this work, damaging micromechanisms in a pearlitic DCI were investigated by means of tensile tests performed on notched specimen, mainly focusing the role played by graphite elements and considering the stress triaxiality influence.

  20. Directional solidification of flake and spheroidal graphite cast iron in low and normal gravity environment

    Science.gov (United States)

    Hendrix, J. C.; Stefanescu, D. M.; Curreri, P. A.

    1987-01-01

    A NASA KC-135 research aircraft, flying repeated low-g trajectories that yield 20-30 sec of 0.1-0.001 g microgravity, has been used to study microgravity solidification's elimination of sedimentation and convection (with formation of unique and advantageous microstructures) for the case of eutectic-composition cast irons. The solidification interface of hypereutectic flake and spheroidal graphite cast irons has been slowly advanced through a 4 mm-diameter rod sample. Sample solidification rates have been correlated with accelerometer data, while independently controlling thermal gradients and solidification rates.

  1. The low-aluminium cast iron of reduced silicon content treated with cerium mischmetal

    OpenAIRE

    M. S. Soiński; P. Susek; Hübner, K.; P. Mierzwa

    2008-01-01

    The work presents the effect of cerium mischmetal used in quantities of 0.1 and 0.2 wt-% and ferrosilicon used in quantities from 0.5% to 1.5% on the alloy matrix and the shape of graphite precipitates in the low-aluminium cast iron from seven heats, basing on the examination of its structure. The hypereutectic cast iron of the relatively high carbon content (4.0÷4.2%) at the prior-to-treatment silicon and manganese content equal to ca. 0.6% and ca. 0.04%, respectively, has been examined.It h...

  2. Research on Welding Test of Grey Cast Iron and Low-Carbon Steel

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    Grey cast iron's welding itself is a complex proble m.So proper welding materials must be selected,complex welding techniques such as preheating before weldingslow cooling after welding etc,should be taken. However the carbon component in low-carbon steel is comparatively low,the carbo n of welded joint will diffuse to the low-carbon steel when it is welded with gr ey cast iron,which will cause the component of carbon greatly increased at the low-carbon steel side in HAZ,high carbon martensite and cracks ...

  3. Effects of microbial redox cycling of iron on cast iron pipe corrosion in drinking water distribution systems.

    Science.gov (United States)

    Wang, Haibo; Hu, Chun; Zhang, Lili; Li, Xiaoxiao; Zhang, Yu; Yang, Min

    2014-11-15

    Bacterial characteristics in corrosion products and their effect on the formation of dense corrosion scales on cast iron coupons were studied in drinking water, with sterile water acting as a reference. The corrosion process and corrosion scales were characterized by electrochemical and physico-chemical measurements. The results indicated that the corrosion was more rapidly inhibited and iron release was lower due to formation of more dense protective corrosion scales in drinking water than in sterile water. The microbial community and denitrifying functional genes were analyzed by pyrosequencing and quantitative polymerase chain reactions (qPCR), respectively. Principal component analysis (PCA) showed that the bacteria in corrosion products played an important role in the corrosion process in drinking water. Nitrate-reducing bacteria (NRB) Acidovorax and Hydrogenophaga enhanced iron corrosion before 6 days. After 20 days, the dominant bacteria became NRB Dechloromonas (40.08%) with the protective corrosion layer formation. The Dechloromonas exhibited the stronger corrosion inhibition by inducing the redox cycling of iron, to enhance the precipitation of iron oxides and formation of Fe3O4. Subsequently, other minor bacteria appeared in the corrosion scales, including iron-respiring bacteria and Rhizobium which captured iron by the produced siderophores, having a weaker corrosion-inhibition effect. Therefore, the microbially-driven redox cycling of iron with associated microbial capture of iron caused more compact corrosion scales formation and lower iron release. PMID:25150521

  4. The thermal fatigue resistance of vermicular cast iron coupling with H13 steel units by cast-in process

    International Nuclear Information System (INIS)

    This paper focuses on improving the thermal fatigue resistance on the surface of vermicular cast iron coupling with inserted H13 steel blocks that had different cross sections, by cast-in processing. The microstructure of bionic units was examined by scanning electron microscope. Micro-hardness and thermal fatigue resistance of bionic samples with varied cross sections and spacings were investigated, respectively. Results show that a marked metallurgical bonding zone was produced at interface between the inserted H13 steel block and the parent material - a unique feature of the bionic structure in the vermicular cast iron samples. The micro-hardness of the bionic samples has been significantly improved. Thermal resistance of the samples with the circular cross section was the highest and the bionics sample with spacing of 2 mm spacing had a much longer thermal fatigue life, thus resulting in the improvement for the thermal fatigue life of the bionic samples, due to the efficient preclusion for the generation and propagation of crack at the interface of H13 block and the matrix.

  5. DEVELOPMENTS IN THE FIELD OF PRODUCTION OF CONTINUOUSLY CAST SLUGS OF COMPOUND CROSS-SECTION OF GREY AND HIGH-STRENGTH CAST IRON

    Directory of Open Access Journals (Sweden)

    V. S. Shumihin

    2016-02-01

    Full Text Available The joint works within the period of 1980–1985 of ITM NAN of Belarus, Institute of casting problems of AN Ukraine and Kaunas works «Tsentrolit» in the field of grey and high-strength cast iron hardening, developments of crystallizers constructions and technologies of production of ingots of compound cross- section by method of horizontal continuous casting, are described.

  6. Effect of bionic coupling units' forms on wear resistance of gray cast iron under dry linear reciprocating sliding condition

    Science.gov (United States)

    Pang, Zuobo; Zhou, Hong; Xie, Guofeng; Cong, Dalong; Meng, Chao; Ren, Luquan

    2015-07-01

    In order to get close to the wear form of guide rails, the homemade linear reciprocating wear testing machine was used for the wear test. In order to improve the wear-resistance of gray cast iron guide rail, bionic coupling units of different forms were manufactured by a laser. Wear behavior of gray-cast-iron with bionic-coupling units has been studied under dry sliding condition at room temperature using the wear testing machine. The wear resistance was evaluated by means of weight loss measurement and wear morphology. The results indicated that bionic coupling unit could improve the wear resistance of gray cast iron. The wear resistance of gray cast iron with reticulation bionic coupling unit is the best. When the load and speed changed, reticulation bionic coupling unit still has excellent performance in improving the wear resistance of gray cast iron.

  7. Inverse thermal analysis method to study solidification in cast iron

    DEFF Research Database (Denmark)

    Dioszegi, Atilla; Hattel, Jesper

    2004-01-01

    solution of a 1-dimensional heat transfer problem connected to solidification of cast alloys. In the analysis, the relation between the thermal state and the fraction solid of the metal is evaluated by a numerical method. This method contains an iteration algorithm controlled by an under relaxation term to......Solidification modelling of cast metals is widely used to predict final properties in cast components. Accurate models necessitate good knowledge of the solidification behaviour. The present study includes a re-examination of the Fourier thermal analysis method. This involves an inverse numerical...... achieve a stable convergence. The heat transfer problem is reduced to 1-dimension to promote the practical application of the method. Thermo-physical properties such as the volumetric heat capacity tabulated in the calculation are introduced as a function of solidifying phases. Experimental equipment was...

  8. Application of cored wire injection method to the producing of vermicular cast iron

    OpenAIRE

    E. Guzik; T. Kleingartner

    2008-01-01

    Thc rcsults of studies on thc use of magnesium alloy in modcrn cod wire injection method tor pmduction of vcrrniculnr ~rsphitcc astirons were described. The injection of Mg corcd wirc lcngth is a trcatmcnt rnczhod which can bc used lo pmcss iron mcltctl in an clcctricinduction fumacc. This paper describes the results of using a high-magnssiurn fcmsilicon alloy in corcd wire (Mg recovcry 45% ) Tor thcproduction OF vcrmicular graphite cast irons at Gicsserci Hcunisch GmbI I Foundry. Thc rcsulrs...

  9. Influencing factors on as-cast and heat treated 400-18 ductile iron grade characteristics

    Directory of Open Access Journals (Sweden)

    I. Riposan

    2007-11-01

    Full Text Available As-cast and heat-treated 400-18 ductile iron (DI grade was obtained in different foundry conditions, as metallic charge, Mg-treatment alloy and inoculation. It was found that the Pearlitic Influence Factor (Px and Antinodulizing Complex Factor (K1 have an important influence on property of DI, depending on the Mn and P level, the metallurgical quality of iron melt, rare earth (RE and inoculation. It was also found that the influence of Mn is depended on the phosphorus and residual elements level in ductile iron. Less than 0.03%P and 0.2%Mn and Px2.0 determines presence of pearlite in as-cast structure, while ferrite structure is obtained after a short annealing heat treatment. Lower level of phosphorus (P1.2. Si has a significant influence on the mechanical properties of heat treated ductile irons: an important decreasing of elongation level and a moderate increasing of yield and tensile strength and their ratio in 150-170 HB typical hardness field. A typical final chemical composition for as-cast 400-18 ductile iron could include 3.5%-3.7%C, 2.4%-2.5%Si, max.0.18%Mn, max.0.025%P, max.0.01%S, 0.04%-0.05%Mgres. for Px<1.5 and K1<1.1. High purity pig iron, RE-bearing FeSiMg and powerful inoculant are also recommended.

  10. Effect of Bi on graphite morphology and mechanical properties of heavy section ductile cast iron

    Directory of Open Access Journals (Sweden)

    Song Liang

    2014-03-01

    Full Text Available To improve the mechanical properties of heavy section ductile cast iron, bismuth (Bi was introduced into the iron. Five castings with different Bi content from 0 to 0.014 wt.% were prepared; and four positions in the casting from the edge to the center, with different solidification cooling rates, were chosen for microstructure observation and mechanical properties test. The effect of the Bi content on the graphite morphology and mechanical properties of heavy section ductile cast iron were investigated. Results show that the tensile strength, elongation and impact toughness at different positions in the five castings decrease with a decrease in cooling rate. With an increase in Bi content, the graphite morphology and the mechanical properties at the same position are improved, and the improvement of mechanical properties is obvious when the Bi content is no higher than 0.011wt.%. But when the Bi content is further increased to 0.014wt.%, the improvement of mechanical properties is not obvious due to the increase of chunky graphite number and the aggregation of chunky graphite. With an increase in Bi content, the tensile fracture mechanism is changed from brittle to mixture ductile-brittle fracture.

  11. State of the art of metal reoxidation study of iron castings

    Directory of Open Access Journals (Sweden)

    R. Vladik

    2007-11-01

    Full Text Available Purpose: Metal reoxidation causes a number of iron castings defects, particularly when pouring them in green-sand moulds. One of them is pinholes the occurrence of which is explained by several hypotheses. One of possible causes is reoxidation processes in the foundry mould cavity. During its flowing in the gating system and in the mould cavity the liquid metal gets into contact with oxygen from air and water vapour. Secondary oxidation of elements takes place in sequence of their affinity to oxygen.Design/methodology/approach: Therefore the authors were aimed at cast irons. Besides indirect methods the reoxidation was researched mainly by direct measurement of oxygen activity during filling of a mould up to solidus temperature. Findings: The use of oxygen activity measurement for direct study of changes caused by reoxidation processes is limited and that it is more suitable for study of the influence of different factors on cast iron crystallization and graphite morphology.Practical implications: Obtained results have confirmed that oxygen activity measurement can serve to the casting quality control. But it is little sensitive for explanation of processes running in a cavity during metal casting.Originality/value: Continuous monitoring of oxygen activity changes in a foundry mould is an original solution since other authors have done their measurements only in a furnace with disposable sensors.

  12. Microstructures and formation mechanism of hypoeutectic white cast iron by isothermal electromagnetic rheocast process

    Directory of Open Access Journals (Sweden)

    Zhang Wanning

    2010-05-01

    Full Text Available An investigation was made on the evolution of microstructures of hypoeutectic white cast iron slurry containing 2.5wt.%C and 1.8wt.%Si produced by rheocasting in which the solidifying alloy was vigorously agitated by electromagnetic stirrer during isothermal cooling processes. The results indicated that under the proper agitating temperatures and speeds applied, the dendrite structures in white cast iron slurry were gradually evolved into spherical structures during a certain agitating time. It also revealed that the bent dendrites were formed by either convection force or by the growth of the dendrites themselves in the bending direction; then, as they were in solidifying, they were gradually being alternated into separated particles and into more spherical structures at the end of the isothermal cooling process. Especially, the dendrites were granulated as the bending process proceeding, which suggested that they were caused by unwanted elements such as sulfur and phosphor usually contained in engineering cast iron. Convective flow of the melt caused corrosion on the dendritic segments where they were weaker in strength and lower in melting temperature because of higher concentration of sulfur or phosphor. And the granulation process for such dendrites formed in the melt became possible under the condition. Certainly, dendrite fragments are another factors considerable to function for spherical particles formation. A new mechanism, regarding to the rheocast structure formation of white cast iron, was suggested based on the structural evolution observed in the study.

  13. Investigation of jatropha seed oil as austempering quenchant for ductile cast iron

    Directory of Open Access Journals (Sweden)

    Akor Terngu

    2014-06-01

    Full Text Available Normal 0 false false false EN-US X-NONE X-NONE MicrosoftInternetExplorer4 Austempering is a multi-step process that includes austenitizing, followed by cooling rapidly enough to avoid the formation of pearlite to a temperature above the martensite start (Ms and then holding until the desired microstructure is formed. It is an isothermal heat treatment process that, when applied to cast iron, produces components that, in many cases, have properties superior to those process by conventional heat treatment. Salt bath has been recognized as the conventional quenching medium for austempering. This study investigates the suitability of jatropha seed oil as quenching medium for asaustempering ductile cast iron. Test samples were austenitized at 9500C; socked for 1hr; austempered for varying periods of 1, 2, 3, 4 and 5hrs. The result showed significant increase in tensile strength and impact energy apart from achieving an appreciable increase in hardness. It also tally with recommended values of ductile cast iron austempered in salt bath, implying that jatropha oil can be used as hot bath for the austempering of ductile cast iron. Keywords: Ausferrite, Austempering, Austenitized, Matrix So, Cked.

  14. Numerical modeling of coupled heat transfer and phase transformation for solidification of the gray cast iron

    DEFF Research Database (Denmark)

    Jabbari, Masoud; Hosseinzadeh, Azin

    2013-01-01

    In the present study the numerical model in 2D is used to study the solidification bahavior of the gray cast iron. The conventional heat transfer is coupled with the proposed micro-model to predict the amount of different phases, i.e. total austenite (c) phase, graphite (G) and cementite (C), in...

  15. The influence of chosen modifiers on stereological parameters of carbides of chromium cast iron

    OpenAIRE

    A. Studnicki; J. Suchoń

    2011-01-01

    The results of investigations of stereological carbides in the modified wear resistance chromium cast iron resistant were introduced in the article. There were following elements: boron, niobium, vanadium, cerium and lanthanum (RE), nitrogen in the composition of modifiers. The influence of used modifiers on such stereological parameters of carbides as: size, perimeter, shape coefficient and volume fraction was showed in tables and on diagrams.

  16. Modelling of Eutectic Saturation Influence on Microstructure in Thin Wall Ductile Iron Casting Using Cellular Automata

    Directory of Open Access Journals (Sweden)

    M. Górny

    2012-12-01

    Full Text Available The mathematical model of the globular eutectic solidification in 2D was designed. Proposed model is based on the Cellular AutomatonFinite Differences (CA-FD calculation method. Model has been used for studies of the primary austenite and of globular eutectic grainsgrowth during the ductile iron solidification in the thin wall casting. Model takes into account, among other things, non-uniformtemperature distribution in the casting wall cross-section, kinetics of the austenite and graphite grains nucleation, and non-equilibriumnature of the interphase boundary migration. Calculation of eutectic saturation influence (Sc = 0.9 - 1.1 on microstructure (austenite and graphite fraction, density of austenite and graphite grains and temperature curves in 2 mm wall ductile iron casting has been done.

  17. The identification of pouring conditions of cast iron to sand moulds

    Directory of Open Access Journals (Sweden)

    B. Borowiecki

    2008-04-01

    Full Text Available The structure and properties of the castings in cast iron put on spheroidization depend especially on the pouring conditions. Decisive factor of local castings properties can be the flow ability of liquid metal in sand mould, which depends not only on chemical constitutions but also on temperature and velocity of pouring. The parameter, which take into consideration various factors is a substitute rheological parameter θ proposed in early author’s papers [1, 2]. The parameter determined in fluidity test can be used to calculation of thickness of rheological boundary layer metal in gating system channel and in casting. The identification a thermal properties of sand mould material has been require of investigation proposed in literature [3, 4]. In the article presented also the experimental of measurement results of metal levels in piezometers located on the horizontal cross gate.

  18. Fatigue behaviour and energy dissipation of a nodular cast iron in ultrasonic fatigue loading

    Directory of Open Access Journals (Sweden)

    H.Q. Xue

    2006-08-01

    Full Text Available Purpose: In the current research, fatigue tests of cast iron (GS51 have been conducted using the ultrasonicfatigue system and monitored by an advanced infrared imaging system in real time. Fatigue damage processeshas been observed and analyzed. Furthermore, heat condition effect has been to analyze.Design/methodology/approach: Fatigue behaviour in the very high cycle regime of 1010 cycles wereinvestigated with a cast iron (GS51 under ultrasonic fatigue test system in ambient air at room temperaturewith a stress ratio R=-1. The influence of frequency was examined by comparing similar data generated onconventional servo hydraulic test systems. An infrared camera was also used to record specimen temperaturesat various load levels caused by internal damping due to cycling at a very high frequency.Findings: The S-N curves obtained show that fatigue failure occurred beyond 109 cycles, fatigue limit does notexist for the cast iron and there is no evidence of frequency effect on the test results. A detailed study on fatiguespecimens subjected to ultrasonic frequency shows that the temperature evolution of the cast iron specimen isvery evident, the temperature increased just at the beginning of the test, the temperature increased depending onthe maximum stress amplitude.Research limitations/implications: Ultrasonic fatigue test methodology had been applied extensively inexploring fatigue lives at very high cycle regime. However, it is a predominant problem that the thermal energydissipation results in increasing of temperature of specimen at very high frequency fatigue experiment. In orderto investigate the heat dissipation of ultrasonic fatigue specimen and understand the influence of temperatureevolution on the fatigue properties, it is necessary to obtain the temperature response of vibratory specimen.Originality/value: Early stage of damage of the cast iron which lead to crack initiation and micro crack growthare characterized by local microstructure

  19. Discussion on "proportional solidification technology" for nodular iron casting method

    Institute of Scientific and Technical Information of China (English)

    ZHOU Gen

    2006-01-01

    The Proportional Solidification Technology believes that advancing the expansion of graphite precipitation is favorable for fully utilizing the expansion to offset the contraction and minimizing feeder size. But this author has proved that advancing the expansion is unfavorable for both feeding from the feeder and the self-feeding by expansion. On contrary, advancing the contraction is favorable for both kinds of feeding and favorable for avoiding shrinkage. The feeding efficiency of feeders cannot be increased by advancing the expansion of the casting, but can only be increased by accelerating cooling and contraction of the casting, and (or) by delaying the freezing of the feeders. In order to fully utilize the expansion to offset the contraction, it is a must to ensure that all inlets and outlets of a casting being poured are blocked rapidly at the moment when pouring is finished. It is pointed out that blocking at the earlier frozen feeder neck is unfavorable for both feeding from the feeder and the self-feeding by expansion; whereas blocking at earlier frozen ingates is favorable for both kinds of feeding.

  20. Casting and stress-strain simulations of a cast ductile iron component using microstructure based mechanical behavior

    International Nuclear Information System (INIS)

    The industrial demand for increased component performance with concurrent reductions in component weight, development times and verifications using physical prototypes drives the need to use the full potential of casting and Finite Element Method (FEM) simulations to correctly predict the mechanical behavior of cast components in service. The mechanical behavior of the component is determined by the casting process, and factors as component geometry and casting process parameters are known to affect solidification and microstructure formation throughout the component and cause local variations in mechanical behavior as well as residual stresses. Though residual stresses are known to be an important factor in the mechanical behavior of the component, the importance of local mechanical behavior is not well established and the material is typically considered homogeneous throughout the component. This paper deals with the influence of solidification and solid state transformation on microstructure formation and the effect of local microstructure variations on the mechanical behavior of the cast component in service. The current work aims to investigate the coupling between simulation of solidification, microstructure and local variations in mechanical behavior and stress-strain simulation. This is done by performing several simulations of a ductile iron component using a recently developed simulation strategy, a closed chain of simulations for cast components, able to predict and describe the local variations in not only elastic but also plastic behavior throughout the component by using microstructural parameters determined by simulations of microstructural evolution in the component during the casting process. In addition the residual stresses are considered. The results show that the FEM simulation results are significantly affected by including microstructure based mechanical behavior. When the applied load is low and the component is subjected to stress levels

  1. Machinability of clean thin-wall gray and ductile iron castings. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Bates, C.E.; Littleton, H.E.; Eleftheriou, E.; Griffin, R.D.; Dwyer, Z.B.; DelSorbo, C.; Sprague, J.

    1997-02-01

    First phase was to develop a laboratory technique for evaluating the machinability of gray and ductile iron; longer term goal is to learn how to modify the foundry process to produce castings meeting all specified mechanical properties while providing improved machining behavior. Microcarbides present in the irons were found to dominate the machinability of iron. Pearlitic irons with acceptable machinability contain 8.9 to 10.5 wt% microcarbides. The weight fraction microcarbides in the iron is influenced by carbide forming element concentrations, presence of elements that retard carbon diffusion, and cooling rate from the eutectic through the eutectoid temperature range. Tool wear rate increased at higher surface machining speeds and fraction microcarbides; all irons containing above 11.5% microcarbides had poor machinability. Graphite size, shape, distribution, etc. had a lesser effect on machinability. Reducing the addition of a foundry grade Ca and Al bearing 75% FeSi inoculant from 0.5 to 0.2% increased the tool life 100%. Inoculation test castings were also poured in a class 40 gray iron; laboratory analysis is currently underway. Exploratory studies were conducted to determine if tool force could be used to predict tool life: torque and feed forces were found to correlate with machinability.

  2. The anaerobic corrosion of carbon steel and cast iron in artificial groundwaters

    International Nuclear Information System (INIS)

    In Sweden, high level radioactive waste will be disposed of in a canister with a copper outer and a cast iron or carbon steel inner. If the iron insert comes into contact with anoxic geological water, anaerobic corrosion leading to the generation of hydrogen will occur. This paper presents a study of the anaerobic corrosion of carbon steel and cast iron in artificial Swedish granitic groundwaters. Electrochemical methods and gas collection techniques were used to assess the mechanisms and rates of corrosion and the associated hydrogen gas production over a range of conditions. The corrosion rate is high initially but is anodically limited by the slow formation of a duplex magnetite film. The effects of key environmental parameters such as temperature and ionic strength on the anaerobic corrosion rate are discussed

  3. Thermal Microstructural Multiscale Simulation of Solidification and Eutectoid Transformation of Hypereutectic Gray Cast Iron

    Science.gov (United States)

    Urrutia, Alejandro; Celentano, Diego J.; Gunasegaram, Dayalan R.; Deeva, Natalia

    2014-08-01

    Although the gray cast iron solidification process has been the subject of several modeling studies, almost all available models appear to deal with only the more widely used hypoeutectic compositions. Models related to hypereutectic gray iron compositions with lamellar (or flake) graphite, and in particular for the proeutectic and eutectoid zones, are hard to find in the open literature. Hence, in the present work, a thermal microstructural multiscale model is proposed to describe the solidification and eutectoid transformation of a slightly hypereutectic composition leading to lamellar graphite gray iron morphology. The main predictions were: (a) temperature evolutions; (b) fractions of graphite, ferrite, and pearlite; (c) density; and (d) size of ferrite, pearlite, and gray eutectic grains; (e) average interlamellar graphite spacing; and (f) its thickness. The predicted cooling curves and fractions for castings with two different compositions and two different pouring temperatures were validated using experimental data. The differences between this model and existing models for hypoeutectic compositions are discussed.

  4. Development of a Cast Iron Fatigue Properties Database for use with Modern Design Methods

    Energy Technology Data Exchange (ETDEWEB)

    DeLa' O, James, D.; Gundlach, Richard, B.; Tartaglia, John, M.

    2003-09-18

    A reliable and comprehensive database of design properties for cast iron is key to full and efficient utilization of this versatile family of high production-volume engineering materials. A database of strain-life fatigue properties and supporting data for a wide range of structural cast irons representing industry standard quality was developed in this program. The database primarily covers ASTM/SAE standard structural grades of ADI, CGI, ductile iron and gray iron as well as an austempered gray iron. Twenty-two carefully chosen materials provided by commercial foundries were tested and fifteen additional datasets were contributed by private industry. The test materials are principally distinguished on the basis of grade designation; most grades were tested in a 25 mm section size and in a single material condition common for the particular grade. Selected grades were tested in multiple sections-sizes and/or material conditions to delineate the properties associated with a range of materials for the given grade. The cyclic properties are presented in terms of the conventional strain-life formalism (e.g., SAE J1099). Additionally, cyclic properties for gray iron and CGI are presented in terms of the Downing Model, which was specifically developed to treat the unique stress-strain response associated with gray iron (and to a lesser extent with CGI). The test materials were fully characterized in terms of alloy composition, microstructure and monotonic properties. The CDROM database presents the data in various levels of detail including property summaries for each material, detailed data analyses for each specimen and raw monotonic and cyclic stress-strain data. The CDROM database has been published by the American Foundry Society (AFS) as an AFS Research Publication entitled ''Development of a Cast Iron Fatigue Properties Database for Use in Modern Design Methods'' (ISDN 0-87433-267-2).

  5. Effects of alloying elements on the microstructure and fatigue properties of cast iron for internal combustion engine exhaust manifolds

    Science.gov (United States)

    Eisenmann, David J.

    In the design of exhaust manifolds for internal combustion engines the materials used must exhibit resistance to corrosion at high temperatures while maintaining a stable microstructure. Cast iron has been used for manifolds for many years by auto manufacturers due to a combination of suitable mechanical properties, low cost, and ease of casting. Over time cast iron is susceptible to microstructural changes, corrosion, and oxidation which can result in failure due to fatigue. This thesis seeks to answer the question: "Can observed microstructural changes and measured high temperature fatigue life in cast iron alloys be used to develop a predictive model for fatigue life?" the importance of this question lies in the fact that there is little data for the behavior of cast iron alloys at high temperature. For this study two different types of cast iron, 50HS and HSM will be examined. Of particular concern for the high Si+C cast irons (and Mo in the case of the HSM cast iron) are subsurface microstructural changes that result due to heat treatment including (1) decarburization, (2) ferrite formation, (3) graphitization, (4) internal oxidation of the Si, (5) high temperature fatigue resistance, and (6) creep potential. Initial results obtained include microstructure examination after being exposed to high temperatures, grain size, nodule size, and hardness measurements. The initial examinations concluded that both cast irons performed fairly similarly, although the microstructure of the HSM samples did show slightly better resistance to high temperature as compared to that of the 50HS. Follow on work involved high temperature fatigue testing of these two materials in order to better determine if the newer alloy, HSM is a better choice for exhaust manifolds. Correlations between fatigue performance and microstructure were made and discussed, with the results examined in light of current and proposed models for predicting fatigue performance based on computational methods

  6. INFLUENCE OF ANNEALING ON HARDNESS OF Cr-Mn-Ni CAST IRONS

    Directory of Open Access Journals (Sweden)

    V. V. Netrebko

    2015-11-01

    Full Text Available The necessary level of material’s hardness is determined by the exploitation conditions and presence of technological operations during manufacturing of articles. Mechanical edge cutting machining of wear resistant materials is impeded because of their high hardness. It is recommended to apply annealing in order to decrease hardness and improve machinability. The purpose of the work consisted in obtaining of regression dependences of cast iron’s macrohardness on its chemical content after annealing at 730 °С. With the use of mathematical experimental design the regression dependences of cast iron’s macrohardness and structural components’ microhardness on С, Cr, Mn, Ni content have been established. The minimal hardness of 27,6 HRC after annealing at 730 °С is obtained in the cast iron containing: 3,9% С; 11,4% Cr; 0,6% Mn; 0,2% Ni. The maximal hardness of 70,4 HRC is obtained when the content is as follows: 1,1% С; 25,6% Cr; 5,4% Mn; 3,0% Ni. Annealing at 730 °С decreases the cast irons’ hardness containing the minimal amount of Cr, Mn and Ni. Annealing at 730 °С is recommended for cast irons alloyed by Mn and Ni for increasing of hardness.

  7. MULTIPURPOSE (WEARPROOF AND ANTIFRICTIONAL COVERINGS ON PRODUCTS FROM CAST IRON

    Directory of Open Access Journals (Sweden)

    A. P. Laskovnev

    2015-11-01

    Full Text Available The basic elements of the new complex technologies providing effective receiving of the materials with the new level of properties are considered. Prospects of creation of new systems for alloying of constructional materials for mechanical engineering with management of their primary crystal structure, hardening mechanisms and resistance to fragile destruction are noted. The resource-saving method of direct surface alloying and modifying (using oxides is developed. Industrial wastes and semi-products of adjacent processes are used as modifying additives. The metals reduction is made by atomic hydrogen and carbon from the special coverings of a casting mold and cores containing high-polymeric connections.

  8. FEATURES OF CHROMIUM DOPING OF WEAR-RESISTANT CAST IRON

    Directory of Open Access Journals (Sweden)

    V. V. Netrebko

    2015-05-01

    Full Text Available The aim of this work analysis of the influence of chromium on the process of carbide formation, changes in chemical composition of the metal substrate in the areas adjacent to the carbides and at the hardness of iron while economy nickel and manganesealloying.

  9. Graphite nodule count and size distribution in thin-walled ductile cast iron

    OpenAIRE

    Pedersen, Karl Martin; Tiedje, Niels Skat

    2008-01-01

    Graphite nodule count and size distribution have been analysed in thin walled ductile cast iron. The 2D nodule counts have been converted into 3D nodule count by using Finite Difference Method (FDM). Particles having a diameter smaller than 5 µm should be neglected in the nodule count as these are inclusions and micro porosities that do not influence the solidification morphology. If there are many small graphite nodules as in thin walled castings only 3D nodule count calculated by FDM will g...

  10. The structure and mechanical properties of pearlitic-ferritic vermicular cast iron

    Directory of Open Access Journals (Sweden)

    E. Guzik

    2012-01-01

    Full Text Available The results of studies on the use of magnesium alloy in modern Tundish + Cored Wire injection method for production of vermicular graphite cast irons were described. The injection of Mg Cored Wire length is a treatment method which can be used to process iron melted in an electric induction furnace. This paper describes the results of using a high-magnesium ferrosilicon alloy in cored wire for the production of vermicular graphite cast irons at the; Tundish + Cored Wire to be injected methods (PE for pearlitic-ferritic matrix GJV with about 25 %ferrite content. The results of calculations and experiments have indicated the length of the Cored Wire to be injected basing on the initial sulfur content and weight of the treated melt. The paper presents a microstructure matrix and vermicular graphite in standard sample and different walled castings. The results of numerous trials have shown that the magnesium Tundish + PE Method process can produce high quality vermicular graphite irons under the specific industrial conditions of the above mentioned foundries.

  11. Melioidosis and idiopathic pulmonary hemosiderosis: a cast-iron case.

    Science.gov (United States)

    Gerhardy, Benjamin; Simpson, Graham

    2013-12-01

    Melioidosis is an infection with clinical importance in northern Australia due to the high associated mortality despite appropriate therapy. This report presents a case of acute pulmonary melioidosis on a background remarkable for the absence of typical risk factors for infection, but the presence of a high iron pulmonary microenvironment consequent to idiopathic pulmonary hemosiderosis. In light of recent genetic analysis of Burkholderia pseudomallei, we postulate that the patient inadvertently provided a high-substrate environment for the iron-scavenging ability of B. pseudomallei's siderophore associated virulence factors, giving her a unique major risk factor for infection. This highlights the importance of considering individual patient factors in addition to population-wide risk factors in the differential diagnosis of a serious illness, and the value of genetic analysis of clinically significant pathogens. PMID:25473541

  12. Melioidosis and idiopathic pulmonary hemosiderosis: a cast-iron case

    OpenAIRE

    Gerhardy, Benjamin; Simpson, Graham

    2013-01-01

    Melioidosis is an infection with clinical importance in northern Australia due to the high associated mortality despite appropriate therapy. This report presents a case of acute pulmonary melioidosis on a background remarkable for the absence of typical risk factors for infection, but the presence of a high iron pulmonary microenvironment consequent to idiopathic pulmonary hemosiderosis. In light of recent genetic analysis of Burkholderia pseudomallei, we postulate that the patient inadverten...

  13. Shrinkage Behaviour of Spheroidal Graphite Cast Iron in Green and Dry Sand Molds for the Benchmarking of Solidification Simulation

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    The effects of metallurgical and processing parameters on the formation of shrinkage cavities and porosities in spheroidal graphite cast iron have been studied, considering the parameters of carbon equivalent, inoculation, casting modulus, mold type (green or dry) and pouring temperature within specific ranges of these variables. Based on the orthogonal experiments, the metallurgical and processing parameters of the minimum casting shrinkage and the maximum casting shrinkage were obtained, and the effects of metallurgical and processing parameters on the formation of shrinkage cavities and porosities in spheroidal graphite cast iron castings were discussed. Finally,two regression equations relating these variables to the formation of shrinkage porosity were derived based upon the orthogonal experiments conducted.

  14. Effects of Carbon Content and Solidification Rate on the Thermal Conductivity of Grey Cast Iron

    Institute of Scientific and Technical Information of China (English)

    Daniel Holmgren; Attila Diószegi; Ingvar L.Svensson

    2008-01-01

    The thermal conductivity/diffusivity of pearlitic grey irons with various carbon contents was investi- gated by the laser flash method. The materials were cast in controlled thermal environments producing three dissimilar cooling rates. The cooling rates together with the carbon content largely influence the thermal conductivity of grey iron. Linear relationships exist between the thermal conductivity and the carbon content, the carbon equivalent, and the fraction of the former primary solidified austenite transformed into pearlite. The results show that the optimal thermal transport properties are obtained at medium cooling rates. Equa- tions are given for the thermal conductivity of pearlite, solidified as pre-eutectic austenite, and the eutectic of grey iron. The thermal conductivity of pearlitic grey iron is modelled at both room temperature and elevated temperatures with good accuracy.

  15. Effects of carbon content and solidification rate on thermal conductivity of grey cast iron

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    The thermal conductivity or diffusivity of pearlitic grey irons with various carbon contents is investigated by the laser flash method. The materials are cast in controlled thermal environments and produced in three dissimilar cooling rates. The cooling rate together with the carbon content largely influence the thermal conductivity of grey iron. Linear relationships exist between the thermal conductivity and the carbon content, the carbon equivalent and the fraction of former primary solidified austenite transformed into pearlite. The work shows that optimal thermal transport properties are obtained at medium cooling rates. Equations describing the thermal conductivity of pearlite,solidified as pre-eutectic austenite, and the eutectic of grey iron are derived. The thermal conductivity of pearlitic grey iron is modeled at both room temperature and elevated temperature with good accuracy.

  16. Study on Bond Ability of Arc-Spraying Coatings with Different Surface Pretreatment on Cast-Iron

    Institute of Scientific and Technical Information of China (English)

    HAO Jian-jun; MA Yue-jin; SHEN Yu-zeng

    2004-01-01

    Arc spraying coatings are widely used in various applications, but uncommon in cast iron substrate. Different surface pretreatment technology is tested on substrates of gray cast iron. Surface roughness and residual stress were measured by TR200 and X-ray diffraction analyzer. Influence of different surface pretreatment methods ( dry blasting and fusebond) on roughness and residual stress was analyzed. The arc-sprayed coatings of wire 3Cr13 (φ2mm) on gray cast iron substrate is studied. The microstructure and interface of bonding layer were observed by SEM. The bond strength was taken by tensile test. Results show that bond strength with grit blasting is higher than fuse-bond; it is feasible to make wire 3Cr13 coating with arc spraying on cast iron substrate roughened by grit blasting.

  17. Influence of rare earths on shrinkage porosity in thin walled ductile cast iron

    DEFF Research Database (Denmark)

    Pedersen, Karl Martin; Tiedje, Niels Skat

    2009-01-01

    Ductile cast iron has been cast in test bars with thickness from 2 to 10 mm. The rare earth elements La and Ce have been added to some of the castings to evaluate their influence on microstructure and shrinkage tendency. Both La and Ce increased the graphite nodule count, especially for thickness...... of 6 mm and below. La gave the best nodule size distribution with many small nodules. La had less shrinkage tendency than Ce in the 10 mm test bars. This tendency was less pronounced for the 6 and 4 mm test bars and other factors may have a large influence at these thicknesses. Increasing the...... temperature T-1, which is controlled by the growth of off-eutectic austenite dendrites, increased the shrinkage tendency....

  18. Behavior of cermets (Fe powder + Al2O3) obtained 'in situ' in cast iron

    International Nuclear Information System (INIS)

    The introduction of hard ceramic particles in a ferrous matrix modifies its behavior when undergoing stresses associated with wear resistance. So that this occurs, the particles must be properly selected, with reference to their hardness, size, shape and dispersion. These compound materials are called MMC (metal matrix composites) or cermets. This work looks at the methodology for producing cast iron pieces using a traditional sand mold casting process, using MMC tablets, and placing them in some areas of the piece that will undergo wear from abrasion. The following steps are described in the production of MMC tablets and of the casting material in the foundry's pilot plant. The material was studied and the metallurgical quality was evaluated together with its resistance to the abrasive wear

  19. Effect of Cu and Mn on the Mechanical Properties and Microstructure of Ductile Cast Iron

    Directory of Open Access Journals (Sweden)

    A.M.Omran

    2014-06-01

    Full Text Available This paper described the method used for producing ductile cast iron (SGI. The processing parameters affecting the production of SGI were studied. These parameters include chemical composition, castings thickness, mechanical properties, alloying elements and microstructure. The chemical composition of producing SGI was optimized. The nodularity was increased with increasing the percentages of Mg content and with decreasing the castings thickness. The amount of pearlite and mechanical properties were increased sharply with increasing Cu and Mn contents in the produced SGI. Empirical equations were correlated to indicate the relations among nodularity, Mg content and other parameters. The results shown also as the post inoculation increased the metallurgical quality was improved. The suitability of SGI as automotive engine was tested and different empirical correlations were obtained

  20. The forty years of vermicular graphite cast iron development in China (PartⅠ

    Directory of Open Access Journals (Sweden)

    CHEN Zheng-de

    2007-05-01

    Full Text Available In China, the research and development of vermicular graphite cast iron (VGCI as a new type of engineering material, were started in the same period as in other developed countries; however, its actual industrial application was even earlier. In China, the deep and intensive studies on VGCI began as early as the 1960s. According to the incomplete statistics to date, more than 600 papers on VGCI have been published by Chinese researchers and scholars at national and international conferences, and in technical journals. More than ten types of production methods and more than thirty types of treatment alloy have been studied. Formulae for calculating the critical addition of treatment alloy required to produce VGCI have been put forward, and mechanisms for explaining the formation of dross during treatment were brought forward. The casting properties, metallographic structure, mechanical and physical properties and machining performance of VGCI, as well as the relationships between them, have all been studied in detail. The Chinese Standards for VGCI and VGCI metallographic structure have been issued. In China, the primary crystallization of VGCI has been studied by many researchers and scholars. The properties of VGCI can be improved by heat treatment and addition of alloying elements enabling its applications to be further expanded. Hundreds of kinds of VGCI castings have been produced and used in vehicles, engines, mining equipment, metallurgical products serviced under alternating thermal load, machinery, hydraulic components, textile machine parts and military applications. The heaviest VGCI casting produced is 38 tons and the lightest is only 1 kg. Currently, the annual production of the VGCI in China is about 200 000 tons. The majority of castings are made from cupola iron without pre-treatment, however, they are also produced from electric furnaces and by duplex melting from cupolaelectric furnaces or blast furnace-electric furnace

  1. The forty years of vermicular graphite cast iron development in China (Part 2

    Directory of Open Access Journals (Sweden)

    CHEN Zheng-de

    2007-08-01

    Full Text Available In China, the research and development of vermicular graphite cast iron (VGCI as a new type of engineering material, were started in the same period as in other developed countries; however, its actual industrial application was even earlier. In China, the deep and intensive studies on VGCI began as early as the 1960s. According to the incomplete statistics to date, more than 600 papers on VGCI have been published by Chinese researchers and scholars at national and international conferences, and in technical journals. More than ten types of production methods and more than thirty types of treatment alloy have been studied. Formulae for calculating the critical addition of treatment alloy required to produce VGCI have been put forward, and mechanisms for explaining the formation of dross during treatment were brought forward. The casting properties, metallographic structure, mechanical and physical properties and machining performance of VGCI, as well as the relationships between them, have all been studied in detail. The Chinese Standards for VGCI and VGCI metallographic structure have been issued. In China, the primary crystallization of VGCI has been studied by many researchers and scholars. The properties of VGCI can be improved by heat treatment and addition of alloying elements enabling its applications to be further expanded. Hundreds of kinds of VGCI castings have been produced and used in vehicles, engines, mining equipment, metallurgical products serviced under alternating thermal load, machinery, hydraulic components, textile machine parts and military applications. The heaviest VGCI casting produced is 38 tons and the lightest is only 1 kg. Currently, the annual production of the VGCI in China is about 200 000 tons. The majority of castings are made from cupola iron without pre-treatment, however, they are also produced from electric furnaces and by duplex melting from cupolaelectric furnaces or blast furnace-electric furnace

  2. The forty years of vermicular graphite cast iron development in China (Part Ⅲ

    Directory of Open Access Journals (Sweden)

    QIU han-quan

    2007-11-01

    Full Text Available In China, the research and development of vermicular graphite cast iron (VGCI as a new type of engineering material, were started in the same period as in other developed countries; however, its actual industrial application was even earlier. In China, the deep and intensive studies on VGCI began as early as the 1960s. According to the incomplete statistics to date, more than 600 papers on VGCI have been published by Chinese researchers and scholars at national and international conferences, and in technical journals. More than ten types of production methods and more than thirty types of treatment alloy have been studied. Formulae for calculating the critical addition of treatment alloy required to produce VGCI have been put forward, and mechanisms for explaining the formation of dross during treatment were brought forward. The casting properties, metallographic structure, mechanical and physical properties and machining performance of VGCI, as well as the relationships between them, have all been studied in detail. The Chinese Standards for VGCI and VGCI metallographic structure have been issued. In China, the primary crystallization of VGCI has been studied by many researchers and scholars. The properties of VGCI can be improved by heat treatment and addition of alloying elements enabling its applications to be further expanded. Hundreds of kinds of VGCI castings have been produced and used in vehicles, engines, mining equipment, metallurgical products serviced under alternating thermal load, machinery, hydraulic components, textile machine parts and military applications. The heaviest VGCI casting produced is 38 tons and the lightest is only 1 kg. Currently, the annual production of the VGCI in China is about 200 000 tons. The majority of castings are made from cupola iron without pre-treatment, however, they are also produced from electric furnaces and by duplex melting from cupolaelectric furnaces or blast furnace-electric furnace

  3. The forty years of vermicular graphite cast iron development in China

    Institute of Scientific and Technical Information of China (English)

    QIU han-quan; CHEN Zheng-de

    2007-01-01

    In China, the research and development of vermicular graphite cast iron (VGCI) as a new type of engineering material, were started in the same period as in other developed countries; however, its actual industrial application was even earlier. In China, the deep and intensive studies on VGCI began as early as the 1960s. According to the incomplete statistics to date, more than 600 papers on VGCI have been published by Chinese researchers and scholars at national and international conferences, and in technical journals. More than ten types of production methods and more than thirty types of treatment alloy have been studied. Formulae for calculating the critical addition of treatment alloy required to produce VGCI have been put forward, and mechanisms for explaining the formation of dross during treatment were brought forward. The casting properties, metallographic structure, mechanical and physical properties and machining performance of VGCI, as well as the relationships between them, have all been studied in detail. The Chinese Standards for VGCI and VGCI metallographic structure have been issued. In China, the primary crystallization of VGCI has been studied by many researchers and scholars. The properties of VGCI can be improved by heat treatment and addition of alloying elements enabling its applications to be further expanded. Hundreds of kinds of VGCI castings have been produced and used in vehicles, engines,mining equipment, metallurgical products serviced under alternating thermal load, machinery, hydraulic components, textile machine parts and military applications. The heaviest VGCI casting produced is 38 tons and the lightest is only 1 kg.Currently, the annual production of the VGCI in China is about 200 000 tons. The majority of castings are made from cupola iron without pre-treatment, however, they are also produced from electric furnaces and by duplex melting from cupolaelectric furnaces or blast furnace-electric furnace. Examples of typical

  4. Fatigue strength of nodular cast iron with regard to heavy-wall applications

    Energy Technology Data Exchange (ETDEWEB)

    Bleicher, Christoph; Wagener, Rainer; Kaufmann, Heinz [Fraunhofer-Institut fuer Betriebsfestigkeit und Systemzuverlaessigkeit LBF, Darmstadt (Germany); Melz, Tobias [Fraunhofer-Institut fuer Betriebsfestigkeit und Systemzuverlaessigkeit LBF, Darmstadt (Germany); TU Darmstadt (Germany). Faculty of Mechanical Engineering

    2015-11-01

    For a proper estimation of the fatigue life of a heavy-walled cast component made of nodular cast iron, sufficient knowledge regarding the cyclic properties of the material is necessary. Based on the material parameters at hand for component design, different fatigue analysis procedures can be used. Elastic and elastic-plastic approaches can be adopted, with the latter being reserved only for local approaches. The present publication summarizes the cyclic material parameters gained during a research project by extensive material tests under stress and strain controlled cyclic loading at different load ratios for three nodular cast iron grades. In addition to an improved knowledge of the cyclic material behavior, the notch, the size effects and the mean stress sensitivity were of special concern during the investigations in order to provide an entire overview of the tested materials and thus input information for both stress and strain based design approaches. Tests were performed for specimens taken from large cast blocks of the nodular cast iron grades EN-GJS-400-18U-LT and EN-GJS-450-18, both with ferritic matrices, and EN-GJS-700-2 with a pearlitic matrix. For some of these materials, mean stress sensitivities above 0.5 were obtained during the investigations. These values are not covered by the common standards, which calculate lower values for the mean stress sensitivity. Cyclic material parameters for stress and strain controlled tests are given in this paper as well as values for the size effect, based on the concept of the highly stressed volume. The effect of different specimen sizes could be shown not only by stress but also by strain controlled tests.

  5. Fatigue strength of nodular cast iron with regard to heavy-wall applications

    International Nuclear Information System (INIS)

    For a proper estimation of the fatigue life of a heavy-walled cast component made of nodular cast iron, sufficient knowledge regarding the cyclic properties of the material is necessary. Based on the material parameters at hand for component design, different fatigue analysis procedures can be used. Elastic and elastic-plastic approaches can be adopted, with the latter being reserved only for local approaches. The present publication summarizes the cyclic material parameters gained during a research project by extensive material tests under stress and strain controlled cyclic loading at different load ratios for three nodular cast iron grades. In addition to an improved knowledge of the cyclic material behavior, the notch, the size effects and the mean stress sensitivity were of special concern during the investigations in order to provide an entire overview of the tested materials and thus input information for both stress and strain based design approaches. Tests were performed for specimens taken from large cast blocks of the nodular cast iron grades EN-GJS-400-18U-LT and EN-GJS-450-18, both with ferritic matrices, and EN-GJS-700-2 with a pearlitic matrix. For some of these materials, mean stress sensitivities above 0.5 were obtained during the investigations. These values are not covered by the common standards, which calculate lower values for the mean stress sensitivity. Cyclic material parameters for stress and strain controlled tests are given in this paper as well as values for the size effect, based on the concept of the highly stressed volume. The effect of different specimen sizes could be shown not only by stress but also by strain controlled tests.

  6. Ultrasonic cavitation erosion of nodular cast iron with ferrite-pearlite microstructure.

    Science.gov (United States)

    Mitelea, Ion; Bordeaşu, Ilare; Pelle, Marius; Crăciunescu, Corneliu

    2015-03-01

    The cavitation erosion of ductile cast iron with ferrite-pearlite microstructure was analyzed based on ultrasonic experiments performed according to ASTM G32-2010 and the resistance was compared to the C45 steel with similar hardness. The microstructural observation of the surface for different exposure times to the ultrasonic cavitation reveals the fact that the process initiates at the nodular graphite-ferrite interface and is controlled by micro-galvanic activities and mechanical factors. The cavitation erosion resistance was evaluated based on the evolution of the mean depth erosion and the mean depth erosion rate as a function of the cavitation time. The cavitation erosion rate of the cast iron is up to 1.32 times higher than the one of the C 45 steel with similar hardness. This is explained by the occurrence of stress concentrators due to the expulsion of the graphite from the metallic matrix. PMID:25465881

  7. Study of biofilm influenced corrosion on cast iron pipes in reclaimed water

    Science.gov (United States)

    Zhang, Haiya; Tian, Yimei; Wan, Jianmei; Zhao, Peng

    2015-12-01

    Biofilm influenced corrosion on cast iron pipes in reclaimed water was systemically studied using the weight loss method and electrochemical impedance spectroscopy (EIS). The results demonstrated that compared to sterile water, the existence of the biofilm in reclaimed water promoted the corrosion process significantly. The characteristics of biofilm on cast iron coupons were examined by the surface profiler, scanning electron microscopy (SEM) and energy dispersive spectroscopy (EDS). The bacterial counts in the biofilm were determined using the standard plate count method and the most probable number (MPN). The results demonstrated that the corrosion process was influenced by the settled bacteria, EPS, and corrosion products in the biofilm comprehensively. But, the corrosion mechanisms were different with respect to time and could be divided into three stages in our study. Furthermore, several corresponding corrosion mechanisms were proposed for different immersion times.

  8. Development of a New Route for Fe-C-Al Cast Iron Production

    Directory of Open Access Journals (Sweden)

    M.A. Maleque

    2010-01-01

    Full Text Available Fe-C-Al alloy system spheroidal graphite cast iron has enormous benefits such as higher strength and hardness, better wear and oxidation resistance etc. at room temperature as well as high temperature. However, its application is not still being popularized due to the production difficulties. In this investigation, a special type of design was developed to perform the magnesium (Mg treatment in the melt. The raw materials were melted in an induction furnace and later liquid metal was treated using pure Mg foil for spherodization in special crucible. The microstructural study was performed using Scanning Electron Microscope (SEM. The chemical analysis shows a great breakthrough in Mg recovery of Fe-C-Al alloy system spheroidal graphite cast iron. It is also shown that the mechanical properties such as hardness, tensile strength and ductility are comparable to the previous research work.

  9. Characteristics of flake graphite in Ni-Mn-Cu cast iron. Part 2.

    OpenAIRE

    Janus, A.

    2010-01-01

    The paper continues the article published by Archives of Foundry Engineering, vol. 9, issue 1/2009, pp. 185-290, that presented influence of chemical composition of hypo- and hypereutectic nickel-manganese-copper alloyed cast iron on properties of the contained flake graphite. In this second part of the research, effect of chemical composition of hypereutectic cast iron containing 3.5÷5.1% C, 1.7÷2.8% Si, 3.5÷10.5 %Ni, 2.0÷8.0% Mn, 0.1÷3.5% Cu, 0.14÷0.17% P and 0.02÷0.04% S on properties of f...

  10. Review of current research and application of ductile cast iron quality monitoring technologies in Chinese foundry industry

    OpenAIRE

    Da-yong Li; Zhen-yu Xu; Xu-liang Ma

    2015-01-01

    There is a long history of studying and making use of ductile cast iron in China. Over the years, the foundrymen in China have carried out a lot of valuable research and development work for measuring parameters and controlling the quality in ductile cast iron production. Many methods, such as rapid metallographic phase, thermal analysis, eutectic expansion ratio, surface tension measurement, melt electrical resistivity, oxygen and sulfur activity measurement, ultrasonic measurement and sound...

  11. Study on the Thermal Fatigue Behavior of Hot Deformed Wear Resistance Cast Iron and Effect of Carbide

    Institute of Scientific and Technical Information of China (English)

    Dong Litao; Liu Rongchang; Li Xingyuan; Chen Xiuhong

    2007-01-01

    The thermal fatigue behavior of wear resistance cast iron with different quantity of deformation has been investigated. The results show that eutectic carbide is the main location and passage for initiation and extension of thermal fatigue cracks, approving that the more serious, the carbide breaks. The higher thermal fatigue resistance of wear resistance cast iron will be and thermal fatigue fracture belongs mainly to brittleness.

  12. A reliable and consistent production technology for high volume compacted graphite iron castings

    Institute of Scientific and Technical Information of China (English)

    Liu Jincheng

    2014-01-01

    The demands for improved engine performance, fuel economy, durability, and lower emissions provide a continual chalenge for engine designers. The use of Compacted Graphite Iron (CGI) has been established for successful high volume series production in the passenger vehicle, commercial vehicle and industrial power sectors over the last decade. The increased demand for CGI engine components provides new opportunities for the cast iron foundry industry to establish efficient and robust CGI volume production processes, in China and globaly. The production window range for stable CGI is narrow and constantly moving. Therefore, any one step single addition of magnesium aloy and the inoculant cannot ensure a reliable and consistent production process for complicated CGI engine castings. The present paper introduces the SinterCast thermal analysis process control system that provides for the consistent production of CGI with low nodularity and reduced porosity, without risking the formation of lfake graphite. The technology is currently being used in high volume Chinese foundry production. The Chinese foundry industry can develop complicated high demand CGI engine castings with the proper process control technology.

  13. Influence of shrinkage porosity on fatigue performance of iron castings and life estimation method

    Directory of Open Access Journals (Sweden)

    Wei Liu

    2016-01-01

    Full Text Available Shrinkage porosity exists more or less in heavy castings, and it plays an important role in the fatigue behavior of cast materials. In this study, fatigue tests were carried out on the QT400-18 cast iron specimens containing random degrees of shrinkage porosity defect. Experimental results showed that the order of magnitude of life scattered from 103 to 106 cycles when the shrinkage percentage ranged from 0.67% to 5.91%. SEM analyses were carried out on the shrinkage porosity region. The inter-granular discontinuous, micro cracks and inclusions interfered with the fatigue sliding or hindering process. The slip in shrinkage porosity region was not as orderly as the ordinary continuous medium. The shrinkage porosity area on fracture surface (SPAFS and alternating stress intensity factor (ASIF were applied to evaluate the tendency of residual life distribution; their relationship was fitted by negative exponent functions. Based on the intermediate variable of ASIF, a fatigue life prediction model of nodular cast iron containing shrinkage porosity defects was established. The modeling prediction was in agreement with the experimental results.

  14. Changes of gas pressure in sand mould during cast iron pouring

    Directory of Open Access Journals (Sweden)

    J. Mocek

    2011-10-01

    Full Text Available The paper presents a test method developed to measure changes of gas pressure in sand moulds during manufacture of iron castings. The pressure and temperature measurements were taken in the sand mould layers directly adjacent to the metal – mould interface. A test stand was described along with the measurement methodology. The sensors used allowed studying the fast-changing nature of the processes which give rise to the gas-originated casting defects. The study examined the influence of binders, clays and refining additives on the nature of the gas evolution process. The effect of the base sand type - quartz or olivine - on the nature of pressure changes was compared. The test stand design ensured the stability of technological parameters in the examined mould elements, and a repeatable process of making pilot castings. The main outcome was classification of sand mixtures in terms of pressure occurring during pouring of iron castings. The obtained results confirm the usefulness of the described method for testing gas pressure occurrence in a sand mould.

  15. The Influence of Saturation of Cast Iron Austenite with Carbon on the Ausferrite Transformation

    Directory of Open Access Journals (Sweden)

    T. Giętka

    2007-07-01

    Full Text Available Austenitizing during quench hardening of the ductile cast iron influences the content of carbon in austenite depending on the soaking heat. On the other hand, the saturation of austenite impacts its transformation in the ausferritizing process of a metal matrix and forming of microstructure. Ductile cast iron with the ferrite matrix was hardened with isothermal transformation in the range of ausferritizing in temperature tpi = 400 i 300 0C and the range of time τpi = 7,5 �� 240 min. Specimens were gradually austenitized. They were soaked in the nominal temperature tγ = 950 0C, then precooled to the temperature tγ’ = 850 and 800 0C. Microstructure was investigated, there were also defined the proportion of austenite in the matrix of the cast iron and the content of carbon in it and hardness and impact strength in unnotched specimens. It was stated, that the precooling temperature deciding on the content of carbon in austenite influences kinetics of the ausferritic transformation, the content of carbon in the γ phase and impact strength and, in a less degree, hardness. As a result of gradual austenitizing the cast iron after quench hardening, in some conditions of treatment, reached mechanical properties corresponding, according to the ASTM A 897 standard, with high grades of ADI. Chilling in the range of austenitizing in temperature 850 and 800 0C led to the decrease of carbon in austenite what influenced positively on the matrix microstructure and properties of the ADI. Investigations in this range will be continued.

  16. Simultaneous oxidation and decarburization of cast iron powder during plasma spraying

    Czech Academy of Sciences Publication Activity Database

    Voleník, Karel; Schneeweiss, Oldřich; Chráska, Tomáš; Dubský, Jiří; Písačka, Jan

    2009-01-01

    Roč. 47, č. 1 (2009), s. 19-24. ISSN 0023-432X R&D Projects: GA AV ČR IAA1041404 Institutional research plan: CEZ:AV0Z20430508; CEZ:AV0Z20410507 Keywords : cast iron powder * plasma spraying * oxidation * decarburization Subject RIV: JK - Corrosion ; Surface Treatment of Materials Impact factor: 1.345, year: 2007 http://kovmat.sav.sk/abstract.php?rr=47&cc=1&ss=19

  17. ELABORATION OF MANAGEMENT PLAN OF SOLID WASTE FROM SMALL CAST IRON FOUNDRIES

    OpenAIRE

    Carlos Alberto Mendes Moraes; Amanda Gonçalves Kieling; Daiane Calheiro; Daniel Canello Pires; Cynthia Fleming Batalha da Silveira; Ana Cristina de Almeida Garcia; Feliciane Andrade Brehm

    2013-01-01

    The foundry industry contributes to society meeting the demand of metal scrap recycling, but, at the same time, it brings a high risk of environmental impact for its many potentially pollutant wastes. Among these, there are slag and used foundry sand (cold cure molding). Through a survey about the production process of a small cast iron company, the collected data was compiled to determine the organizational setting in terms of generation and segregation of waste. From a complete ...

  18. Fatigue analysis-based numerical design of stamping tools made of cast iron

    OpenAIRE

    Ben Slima, Khalil; Penazzi, Luc; Mabru, Catherine; Ronde-Oustau, François

    2013-01-01

    International audience This work concerns stress and fatigue analysis of stamping tools made of cast iron with an essentially pearlitic matrix and containing foundry defects. Our approach consists at first, in coupling the stamping numerical processing simulations and structure analysis in order to improve the tool stiffness geometry for minimizing the stress state and optimizing their fatigue lifetime. The method consists in simulating the stamping process by considering the tool as a per...

  19. Microstructure Formation and Fracturing Characteristics of Grey Cast Iron Repaired Using Laser

    OpenAIRE

    Peng Yi; Pengyun Xu; Changfeng Fan; Guanghui Yang; Dan Liu; Yongjun Shi

    2014-01-01

    The repairing technology based on laser rapid fusion is becoming an important tool for fixing grey cast iron equipment efficiently. A laser repairing protocol was developed using Fe-based alloy powders as material. The microstructure and fracturing feature of the repaired zone (RZ) were analyzed. The results showed that regionally organized RZ with good density and reliable metallurgical bond can be achieved by laser repairing. At the bottom of RZ, dendrites existed in similar direction and e...

  20. The forty years of vermicular graphite cast iron development in China (PartⅠ)

    OpenAIRE

    QIU Han-quan; CHEN Zheng-de

    2007-01-01

    In China, the research and development of vermicular graphite cast iron (VGCI) as a new type of engineering material, were started in the same period as in other developed countries; however, its actual industrial application was even earlier. In China, the deep and intensive studies on VGCI began as early as the 1960s. According to the incomplete statistics to date, more than 600 papers on VGCI have been published by Chinese researchers and scholars at national and international conferences,...

  1. The forty years of vermicular graphite cast iron development in China (Part 2)

    OpenAIRE

    CHEN Zheng-de; QIU Han-quan

    2007-01-01

    In China, the research and development of vermicular graphite cast iron (VGCI) as a new type of engineering material, were started in the same period as in other developed countries; however, its actual industrial application was even earlier. In China, the deep and intensive studies on VGCI began as early as the 1960s. According to the incomplete statistics to date, more than 600 papers on VGCI have been published by Chinese researchers and scholars at national and international conferences,...

  2. The influence of chosen modifiers on stereological parameters of carbides of chromium cast iron

    Directory of Open Access Journals (Sweden)

    A. Studnicki

    2011-07-01

    Full Text Available The results of investigations of stereological carbides in the modified wear resistance chromium cast iron resistant were introduced in the article. There were following elements: boron, niobium, vanadium, cerium and lanthanum (RE, nitrogen in the composition of modifiers. The influence of used modifiers on such stereological parameters of carbides as: size, perimeter, shape coefficient and volume fraction was showed in tables and on diagrams.

  3. Value/impact of design criteria for cast ductile iron shipping casks

    International Nuclear Information System (INIS)

    The ductile failure criteria proposed in the Base report appear appropriate except that stress intensity values, S/sub m/ should be based on lower safety factors and ductility should be added as a criterion. A safety factor for stress intensity, s/sub m/ of 4 is recommended rather than 3 on minimum ultimate tensile strength, S/sub u/ in accordance with ASME code philosophy of assigning higher safety factors to cast ductile iron than to steel. This more conservative approach has no impact on costs since the selection of wall thickness is controlled by shielding rather than by stress considerations. The addition of a ductility criterion is recommended because of the problems associated with the selection of appropriate brittle failure criteria and the potential for cast ductile iron to have extremely low elongation at failure. Neither a materials nor a linear elastic fracture mechanics (LEFM) approach appear to be viable for demonstrating the prevention of brittle failure in cast ductile iron shipping casks. It is possible that the analytic methods predict brittle failure because of extremely conservative assumptions whereas real casks may not fail. Model drop tests could be used to demonstrate containment integrity. It is estimated that a risk committment of at least $1,000,000 would be required for engineering, design, model fabrication and testing. Before taking such risks, a mechanism should be found to obtain concurrence from NRC that the results of the test would be acceptable. Probabilistic approaches or model testing could be used to demonstrate the acceptability of cast ductile iron casks from a brittle failure point of view. Before probabilistic methods can be used, the NRC would have to be persuaded to accept the approach of the Competent Authority in West Germany or more formalized methods for probabilistic risk assessments

  4. Composition changes of cast iron particles due to reactions in a plasma stream

    Czech Academy of Sciences Publication Activity Database

    Voleník, Karel; Schneeweiss, Oldřich; Chráska, Tomáš; Kolman, Blahoslav Jan; Chráska, Pavel

    Vol. 1. Shrewsbury : European Powder Metallurgy Association, 2010, s. 143-150. ISBN 1899072101. [Powder Metallurgy World Congress & Exhibition – PM2010. Florencie (IT), 10.10.2010-14.10.2010] R&D Projects: GA ČR GA106/08/1240 Institutional research plan: CEZ:AV0Z20430508; CEZ:AV0Z20410507 Keywords : Cast Iron * Plasma Spraying * Decarburization * Oxidation Subject RIV: JG - Metallurgy

  5. Control of Wear-Resistance Properties in Ti-added Hypereutectic High Chromium Cast Iron

    OpenAIRE

    Liu, Qiang

    2012-01-01

    High chromium cast iron (HCCI) is considered as one of the most useful wear resistance materials and their usage are widely spread in industry. The wear resistance and mechanical properties of HCCI mainly depend on type, size, number, morphology of hard carbides and the matrix structure (γ or α). The Hypereutectic HCCI with large volume fractions of hard carbides is preferred to apply in wear applications. However, the coarser and larger primary M7C3 carbides will be precipitated during the s...

  6. Microstructure Evaluation and Wear-Resistant Properties of Ti-alloyed Hypereutectic High Chromium Cast Iron

    OpenAIRE

    Liu, Qiang

    2013-01-01

    High chromium cast iron (HCCI) is considered as one of the most useful wear resistance materials and their usage are widely spread in industry. The mechanical properties of HCCI mainly depend on type, size, number, morphology of hard carbides and the matrix structure (γ or α). The hypereutectic HCCI with large volume fractions of hard carbides is preferred to apply in wear applications. However, the coarser and larger primary M7C3 carbides will be precipitated during the solidification of the...

  7. Numerical modeling and experimental validation of microstructure in gray cast iron

    DEFF Research Database (Denmark)

    Jabbari, Masoud; Davami, Parviz; Varahram, Naser

    2012-01-01

    To predict the amount of different phases in gray cast iron by a finite difference model (FDM) on the basis of cooling rate (R), the volume fractions of total γ phase, graphite, and cementite were calculated. The results of phase composition were evaluated to find a proper correlation with cooling...... to correlate the phase volume fraction to hardness. The results are compared with experimental data and show reasonable agreement....

  8. Influencing factors on as-cast and heat treated 400-18 ductile iron grade characteristics

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    As-cast and heat-treated 400-18 ductile iron (DI) grade was obtained in different foundry conditions, as metallic charge, Mg-treatment alloy and inoculation. It was found that the Pearlitic Influence Factor (Px) and Antinodulizing Complex Factor (K1) have an important influence on property of DI, depending on the Mn and P level, the metallurgical quality of iron melt, rare earth (RE) and inoculation. It was also found that the influence of Mn is depended on the phosphorus and residual elements level in ductile iron. Less than 0.03%P and 0.2%Mn and Px<2.0 are the basic conditions to obtain as-cast ferritic structure. At the same lower level of Mn and P, the increasing of residual elements (Px>2.0) determines presence of pearlite in as-cast structure, while ferrite structure is obtained after a short annealing heat treatment. Lower level of phosphorus (P<0.025%) and residual elements (Px<2.0) allow to use relative high Mn content (0.32%-0.38%), in condition of ferritic structure, including in as-cast state. High P (0.04%-0.045%) and Mn (0.25%-0.35%) content stabilized pearlite, especially at lower level of residual elements (Px <2.0). Antinodulizing action of elements was counteracted up to K1=2.0 level, by RE included in Mg-treatment alloy, which are beneficial for K1<1.2 and compulsory for K1>1.2. Si has a significant influence on the mechanical properties of heat treated ductile irons: an important decreasing of elongation level and a moderate increasing of yield and tensile strength and their ratio in 150-170 HB typical hardness field. A typical final chemical composition for as-cast 400-18 ductile iron could include 3.5%-3.7%C, 2.4%-2.5%Si, max.0.18%Mn, max.0.025%P, max.0.01%S, 0.04%-0.05%Mgres.for Px<1.5 and K1<1.1. High purity pig iron, RE-bearing FeSiMg and powerful inoculant are also recommended.

  9. Estimation of integrity of cast-iron cask against impact due to free drop test, (1)

    International Nuclear Information System (INIS)

    Ductile cast iron is examined to use for shipping and storage cask from a economic point of view. However, ductile cast iron is considered to be a brittle material in general. Therefore, it is very important to estimate the integrity of cast iron cask against brittle failure due to impact load at 9 m drop test and 1 m derop test on to pin. So, the F.E.M. analysis which takes nonlinearity of materials into account and the estimation against brittle failure by the method which is proposed in this report were carried out. From the analysis, it is made clear that critical flaw depth (the minimum depth to initiate the brittle failure) is 21.1 mm and 13.1 mm in the case of 9 m drop test and 1 m drop test on to pin respectively. These flaw depth can be detected by ultrasonic test. Then, the cask is assured against brittle failure due to impact load at 9 m drop test and 1 m drop test on to pin. (author)

  10. Effects of slope plate variable and reheating on semi-solid structure of ductile cast iron

    Institute of Scientific and Technical Information of China (English)

    M. Nili-Ahmadabadi; F. Pahlevani; P. Babaghorbani

    2008-01-01

    Semi-solid metal casting and forming are known as a promising process for a wide range of metal alloys production. In spite of growing application of semi-solid processed light alloys, a few works have been reported about semi-solid processing of iron and steel. In this research inclined plate was used to change dendritic structure of iron to globular one. The effects of length and slope of plate on the casting structure were examined. The results show that the process can effectively change the dendritic structure to globular. In the slope plate angle of 7.5°and length of 560 mm with cooling rate of 67K·s-1 the optimum nodular graphite and solid globular particle were achieved.The results also show that by using slope plate inoculant fading can be prevented more easily since the total time of process is rather short.In addition, the semi-solid ductile cast iron prepared by inclined plate method, was reheated to examine the effect of reheating conditions on the microstructure and coarsening kinetics of the alloy. Solid fraction at different reheating temperatures and holding time was obtained and based on these results the optimum reheating temperature range was determined.

  11. Effect of Titanium on the Mechanical Properties and Microstructure of Gray Cast Iron for Automotive Applications

    Science.gov (United States)

    Gelfi, M.; Gorini, D.; Pola, A.; La Vecchia, G. M.

    2016-07-01

    Lamellar gray cast iron, with a mainly pearlitic microstructure, is widely used in the automotive industry, mostly in the manufacturing of brake disks. This work analyzes in depth the effects of small variations of titanium content on the microstructure and mechanical properties of cast iron brake disks. For this purpose, eight different heats of EN-GJL-250 cast iron were selected, with a similar chemical composition but with different titanium contents, varying from 0.013 to 0.031%. The drops in mechanical strength and hardness values measured on the high-Ti samples were correlated to microstructural variations quantitatively observed by means of optical and scanning electron microscope. It was found that titanium combines to form titanium nitrides, suppressing the beneficial microstructural effects of nitrogen at solidification. Residual nitrogen, if present in sufficient quantity, promotes the nucleation of primary austenite from the liquid and the formation of a fine microstructure, with small eutectic cells and lower graphite content. Such a microstructure provides brake disks with better mechanical properties. The interpretation of results was further supported by thermal analysis and thermodynamic calculations.

  12. Laser powder surfacing of the Si-Mo spheroidal cast iron with nickel powder

    Directory of Open Access Journals (Sweden)

    A. Klimpel

    2006-04-01

    Full Text Available Purpose: Investigation results are presented of the effect of main parameters of laser powder surfacing of the Si-Mo spheroidal cast iron with the nickel based powder on quality and shape of padding welds and portion of the substrate material in the padding weld.Design/methodology/approach: It was shown basing on investigation of the process of laser powder surfacing with the nickel based powder onto the spheroidal cast iron substrate that it is feasible to make high quality padding welds in the relatively wide range of parameters.Findings: Investigation results presented in the paper were carried out to determine quality of padding welds applied by laser powder surfacing with the nickel based powder onto the alloy spheroidal cast iron and especially to determine the padding welds adhesion to the substrate.Practical implications: It is possible to control the portion of the substrate material in the padding weld with high accuracy in a wide range from even a few per cent, by the relevant setting of the line energy of the laser beam and the powder feed rate.Originality/value: The developed implant test makes the qualitative and quantitative assessment possible of the adhesion of the padding weld to the substrate, Table 5, Figs. 7 to 11. All padding welds made within the range of the optimum welding parameters demonstrated very good adhesion and the break, depending on the nickel padding weld thickness, occurred in the fusion area or by pulling part of the padding weld out.

  13. The low-aluminium cast iron of reduced silicon content treated with cerium mischmetal

    Directory of Open Access Journals (Sweden)

    M. S. Soiński

    2008-07-01

    Full Text Available The work presents the effect of cerium mischmetal used in quantities of 0.1 and 0.2 wt-% and ferrosilicon used in quantities from 0.5% to 1.5% on the alloy matrix and the shape of graphite precipitates in the low-aluminium cast iron from seven heats, basing on the examination of its structure. The hypereutectic cast iron of the relatively high carbon content (4.0÷4.2% at the prior-to-treatment silicon and manganese content equal to ca. 0.6% and ca. 0.04%, respectively, has been examined.It has been found that the performed treatment leads to the change in the alloy matrix from the nearly almost pearlitic to the ferritic-pearlitic one accompanied by changes in the shape of graphite precipitates. Due to applying both of the mentioned substances in the above stated amounts the graphite precipitates in cast iron have taken the shape of nodular and vermicular ones, and no presence of flake graphite has been revealed. A quantitative analysis of the performed treatment i.e. determining the fractions of graphite precipitates of different shapes has been possible by means of a computer image analyser.

  14. PECULIARITIES OF PROCESSES OF CARBIDE FORMATION AND DISTRIBUTION OF Cr, Mn AND Ni IN WHITE CAST IRONS

    Directory of Open Access Journals (Sweden)

    V. V. Netrebko

    2015-11-01

    Full Text Available During crystallization of castings from white cast iron, carbides Me3С, Me7С3, Me23С6 were formed depending on chromium and carbon content. Impeded chromium diffusion caused formation of thermodynamically unstable and non-uniform phases (carbides. During heat treatment process stable equilibrium phases were formed as a result of rearrangement of the carbides’ crystal lattice, replacement of iron, manganese, nickel and silicon atoms by chromium atoms. The allocated atoms concentrated, forming inclusions of austenite inside the carbides. Holding during 9 hours at 720 °С and annealing decreased the non-uniformity of chromium distribution in the metallic base of cast iron containing 11,5 % Cr, and increased it in the cast iron containing 21,5 % Cr. Holding during 4.5 hours at 1050 °С and normalization decreased the non-uniformity of chromium distribution in the metallic base of cast iron containing 21,5 % Cr, and increased it in cast iron containing 11,5 % Cr.

  15. High Cr white cast iron/carbon steel bimetal liner by lost foam casting with liquid-liquid composite process

    Directory of Open Access Journals (Sweden)

    Xiao Xiaofeng

    2012-05-01

    Full Text Available Liners in wet ball mill for mineral processing industry must bear abrasive wear and corrosive wear, and consequently, the service life of the liner made from traditional materials, such as Hadfield steel and alloyed steels, is typically less than ten months. Bimetal liner, made from high Cr white cast iron and carbon steel, has been successfully developed by using liquid-liquid composite lost foam casting process. The microstructure and interface of the composite were analyzed using optical microscope, SEM, EDX and XRD. Micrographs indicate that the boundary of bimetal combination regions is staggered like dogtooth, two liquid metals are not mixed, and the interface presents excellent metallurgical bonding state. After heat treatment, the composite liner specimens have shown excellent properties, including hardness > 61 HRC, fracture toughness αk >16.5 J·cm-2 and bending strength >1,600 MPa. Wear comparison was made between the bimetal composite liner and alloyed steel liner in an industrial hematite ball mill of WISCO, and the results of eight-month test in wet grinding environment have proved that the service life of the bimetal composite liner is three times as long as that of the alloyed steel liner.

  16. Effects of Rare Earths and Al on Structure and Performance of High Chromium Cast Iron Containing Wolfram

    Institute of Scientific and Technical Information of China (English)

    Guo Erjun; Wang Liping; Huang Yongchang; Fu Yuanke

    2006-01-01

    Effects of RE and Al on the structure, impact toughness, hardness, and wear resistance of high chromium cast iron containing wolfram were investigated.The results show that without modification the volume fraction of austenite is high and the carbide appears to be thick lath and the grain size is relatively large;proper modification using RE combined with Al can reduce volume fraction of residual austenite in the as-cast structure obviously, refine grain size of primary austenite notably, and make the morphology of carbide changing from thick lath to thin lath, rosette, and feather-like modification can also increase hardness, wear resistance and impact toughness of cast iron.

  17. The influence of boron on the abrasion wear resistance of 17%Cr white cast iron

    International Nuclear Information System (INIS)

    A study of the abrasion wear resistance of the 2.7C-17Cr-0.7Mo white cast irons with different structures alloyed with boron ranging from 0.1% to 1.3% is carried out. Eleven heat treatments were used to find the optimum treatment. Three conditions (as-cast, martensitic and austenitic) are adopted for various tests. The microstructure and three-dimensional morphology of compounds are examined by optical microscope and SEM respectively. X-ray diffractometer is employed to analyze the compound phases. A high-stress abrasive wear tests is performed with loose SiO/sub 2/ and SiC abrasives in a metal track wear tester. Another abrasive wear test is conducted with wet SiO/sub 2/ abrasives in a rubber wheel tester. The hardness and fracture toughness of these alloys was also measured. With increasing boron content fracture toughness decreases. It is noted that if the irons contained about same compound volume, the abrasion wear resistance in present wear systems are much better than the irons without boron against SiO/sub 2/ abrasives, and the toughness is equivalent to 15 Cr irons without boron. Finally, considering the wear resistance and fracture toughness, the test results would provide a basis for optimizing these properties in selecting materials for a given wear component

  18. Property enhancement of cast iron used for nuclear casks

    Science.gov (United States)

    Behera, R. K.; Mahto, B. P.; Dubey, J. S.; Mishra, S. C.; Sen, S.

    2016-01-01

    Ductile iron (DI) is a preferred material for use in various structural, automotive, and engineering fields because of its excellent combination of strength, toughness, and ductility. In the current investigation, we elucidate the relationship between the morphological and mechanical properties of DI intended for use in safety applications in the nuclear industry. DI specimens with various alloying elements were subjected to annealing and austempering heat treatment processes. A faster cooling rate appeared to increase the nodule count in austempered specimens, compensating for their nodularity value and subsequently decreasing their ductility and impact strength. The ductility and impact energy values of annealed specimens increased with increasing ferrite area fraction and nodularity, whereas an increase in the amounts of Ni and Cr resulted in an increase of hardness via solid solution strengthening. Austempered specimens were observed to be stronger than annealed specimens and failed in a somewhat brittle manner characterized by a river pattern, whereas the ductile failure mode was characterized by the presence of dimples.

  19. Nano-scale orientation mapping of graphite in cast irons

    International Nuclear Information System (INIS)

    A diametrical section of a graphite spheroid from a ductile iron sample was prepared using the focused ion beam-lift out technique. Characterization of this section was carried out through automated crystal orientation mapping in a transmission electron microscope. This new technique automatically collects electron diffraction patterns and matches them with precalculated templates. The results of this investigation are crystal orientation and phase maps of the specimen, which bring new light to the understanding of growth mechanisms of this peculiar graphite morphology. This article shows that mapping the orientation of carbon-based materials such as graphite, which is difficult to achieve with conventional techniques, can be performed automatically and at high spatial resolution using automated crystal orientation mapping in a transmission electron microscope. - Highlights: • ACOM/TEM can be used to study the crystal orientation of carbon-based materials. • A spheroid is formed by conical sectors radiating from a central nuclei. • Misorientations exist within the conical sectors, defining various orientation domains

  20. Impacts of the structure and processing conditions on the voltage arise in machining of gray cast irons

    Directory of Open Access Journals (Sweden)

    M. Aksoy

    2007-12-01

    Full Text Available Purpose: Machining is one of the most widely used manufacturing processes. The machining of gray cast iron is important because of wide application of these materials in various industries. The machinability studies have been carried out for these materials and it was reported that the amount of graphite in cast irons was one of the influential factor in tool wear during machining. This study is aimed to provide new approach to examine tool life by considering voltage arise during machining of gray cast irons.Design/methodology/approach: The experimental study carried out to measure voltage values during various machining conditions such as cutting speeds, feed rates and depth of cut. Chemical compositions of the four different gray cast irons were machined and the experimental results were compared to the machining of brass and steel. The selected machining conditions were 0.16, 0.32 and 0.48 mm feed rates, 0.5, 1 and 1.5 mm depths of cut and 125, 250 and 355 rpm spindle speeds, respectively.Findings: It was observed that the voltage difference was detected during the machining of cast iron specimens. This was due to increase of graphite particles within total intersections. This would lead to conclusion that high graphite particles would increase voltage and this would provide information about tool wear.Research limitations/implications: Because of being cheap, the usage of cast iron with lamella graphite particles in specific electric circuits to be used in industrial applications need to be further investigated. Also whether or not the cost iron with lamella graphite particles can be used as voltage storage under intensive stress needs to be investigated.Originality/value: Impacts of the structure and processing conditions on the voltage arise in machining of gray cast irons.

  1. The Role of Silicon in the Solidification of High-Cr Cast Irons

    Science.gov (United States)

    Bedolla-Jacuinde, A.; Rainforth, M. W.; Mejía, I.

    2013-02-01

    This work analyzes the effect of different additions of silicon (0 to 5.0 pct) on the structure of a high-Chromium white cast iron, with chromium content of 16.8 pct and carbon 2.56 pct. The alloys were analyzed in both as-cast and heat-treated conditions. Casting was undertaken in metallic molds that yielded solidification rates faster than in commercial processes. Nevertheless, there was some degree of segregation of silicon; this segregation resulted in a refinement in the microstructure of the alloy. Silicon also generated a greater influence on the structure by destabilizing the austenitic matrix, and promoted greater precipitation of eutectic carbides. Above 3 pct silicon, pearlite formation occurred in preference to martensite. After the destabilization heat treatment, the matrix structure of the irons up to 3 pct Si consisted of secondary carbides in a martensitic matrix with some retained austenite; higher Si additions produced a ferritic matrix. The different as-cast and heat-treated microstructures were correlated with selected mechanical properties such as hardness, matrix microhardness, and fracture toughness. Silicon additions increased matrix microhardness in the as-cast conditions, but the opposite phenomenon occurred in the heat-treated conditions. Microhardness decreased as silicon content was increased. Bulk hardness showed the same behavior. Fracture toughness was observed to increase up to 2 pct Si, and then decreased for higher silicon contents. These results are discussed in terms of the effect of eutectic carbides' size and the resulting matrix due to the silicon additions.

  2. Production and Machining of Thin Wall Gray and Ductile Cast Iron

    Energy Technology Data Exchange (ETDEWEB)

    Fleischman, E.H. (INEEL POC); Li, H.; Griffin, R.; Bates, C.E.; Eleftheriou, E.

    2000-11-03

    The University of Alabama at Birmingham, in cooperation with the American Foundry Society, companies across North America, with support from the U.S. Department of Energy, is conducting a project to develop an understanding of the factors that control the machinability of cast gray and ductile iron. Differences of as much as 500% have been found in machinability have been observed at the same strength. The most machinable irons were those with a high cell counts and few carbonitride inclusions. Additions of tin and copper can be added to both gray and ductile iron to stabilize the pearlite, but excessive additions (above those required to produce the desired pearlite content) degrade the machinability.

  3. Fatigue crack tip damaging micromechanisms in a ferritic-pearlitic ductile cast iron

    Directory of Open Access Journals (Sweden)

    Francesco Iacoviello

    2015-07-01

    Full Text Available Due to the peculiar graphite elements shape, obtained by means of a chemical composition control (mainly small addition of elements like Mg, Ca or Ce, Ductile Cast Irons (DCIs are able to offer the good castability of gray irons with the high mechanical properties of irons (first of all, toughness. This interesting properties combination can be improved both by means of the chemical composition control and by means of different heat treatments(e.g. annealing, normalizing, quenching, austempering etc. In this work, fatigue crack tip damaging micromechanisms in a ferritic-pearlitic DCI were investigated by means of scanning electron microscope observations performed on a lateral surface of Compact Type (CT specimens during the fatigue crack propagation test (step by step procedure, performed according to the “load shedding procedure”. On the basis of the experimental results, different fatigue damaging micromechanisms were identified, both in the graphite nodules and in the ferritic – pearlitic matrix.

  4. Influence of Addition of Briquettes with Dust Content into the Charge of Electric Induction Furnace on Cast Iron Quality

    OpenAIRE

    A. Pribulová; P. Futáš; Baricová, D.

    2012-01-01

    Foundry dust from blasting and grinding of castings contain a high amount of iron, ergo it is possible its recycling in foundry process.Dust was compacted by briquetting, two kinds of briquettes were prepared (A contained 95% magnetic part of dust from casting blasting+5% bentonite and B contained 95% mixture of dust from casting grinding and magnetic part of dust from casting blasting + 5%bentonite) and used as a part of charge into the electric induction furnace. It was found that addition ...

  5. An approach for the fatigue estimation of porous cast iron based on non-destructive testing results

    Directory of Open Access Journals (Sweden)

    Heinrietz André

    2014-06-01

    Full Text Available Big cast iron components made of spheroidal cast iron allow constructing big structures such as stone mills, engine blocks or wind mills with acceptable expenses. Thus, in economically optimized cast processes pores cannot be always prevented in thick walled cast iron components and these components are often rejected because of safety reasons. On the one hand the fatigue performance of high loadable spheroidal cast iron components is reduced significantly by the presence of local porosities which has been pointed out in the past. On the other hand concepts for the fatigue estimation based on fracture mechanics which take the size and localization of the defect into account can lead to erroneous estimations because the defect is modelled as a crack. The challenge of an estimation method is to derive a fatigue life without the necessity to perform component tests. In the contribution an estimation method is presented which is able to determine the fatigue strength of a material volume taking the pores into account. The method can be applied based on data from computer tomographic X-ray (CT or Sampling Phased Array (SPA ultrasonic analyses. The method is presented for three spheroidal cast iron types: ferritic GJS-400-18, ferritic GJS-450-15 with high silicon content and perlitic GJS-700-3.

  6. Influence of Addition of Briquettes with Dust Content into the Charge of Electric Induction Furnace on Cast Iron Quality

    Directory of Open Access Journals (Sweden)

    A. Pribulová

    2012-09-01

    Full Text Available Foundry dust from blasting and grinding of castings contain a high amount of iron, ergo it is possible its recycling in foundry process.Dust was compacted by briquetting, two kinds of briquettes were prepared (A contained 95% magnetic part of dust from casting blasting+5% bentonite and B contained 95% mixture of dust from casting grinding and magnetic part of dust from casting blasting + 5%bentonite and used as a part of charge into the electric induction furnace. It was found that addition of briquettes has had an influence of a chemical composition of cast iron above all on content of sulphur, phosphorus and silicon. It was not reflected in decrease in tensile strength and in microstructure. Yield of metal from briquettes was not lower then 70%.

  7. Using Cored Wires Injection 2PE-9 Method in the Production of Ferritic Si-Mo Ductile Iron Castings

    OpenAIRE

    E. Guzik; D. Wierzchowski

    2012-01-01

    The results of studies on the use of modern two cored wires injection method for production of ferritic nodular cast iron (ductile iron) with use of unique implementation of drum ladle as a treatment / transport and casting ladle instead vertical treatment ladle was described. The injection of length of Ø 9mm wires, cored: in FeSi + Mg nodulariser mixture and inoculant master alloy is a treatment method which can be used to produce iron melted in coreless induction furnace. This paper describ...

  8. Alloyed White Cast Iron With Precipitates of Spheroidal Vanadium Carbides VC

    Directory of Open Access Journals (Sweden)

    M. Kawalec

    2012-12-01

    Full Text Available The paper presents the results of tests on the spheroidising treatment of vanadium carbides VC done with magnesium master alloy and mischmetal. It has been proved that the introduction of magnesium master alloy to an Fe-C-V system of eutectic composition made 34% of carbides crystallise in the form of spheroids. Adding mischmetal to the base alloy melt caused 28% of the vanadium carbides crystallise as dendrites. In base alloy without the microstructure-modifying additives, vanadium carbides crystallised in the form of a branched fibrous eutectic skeleton.Testing of mechanical properties has proved that the spheroidising treatment of VC carbides in high-vanadium cast iron increases thetensile strength by about 60% and elongation 14 - 21 times, depending on the type of the spheroidising agent used.Tribological studies have shown that high-vanadium cast iron with eutectic, dendritic and spheroidal carbides has the abrasive wearresistance more than twice as high as the abrasion-resistant cast steel.

  9. Eutectic cell and nodule count as the quality factors of cast iron

    Directory of Open Access Journals (Sweden)

    E. Fraś

    2008-10-01

    Full Text Available In this work the predictions based on a theoretical analysis aimed at elucidating of eutectic cell count or nodule counts N wereexperimentally verified. The experimental work was focused on processing flake graphite and ductile iron under various inoculationconditions in order to achieve various physicochemical states of the experimental melts. In addition, plates of various wall thicknesses, s were cast and the resultant eutectic cell or nodule counts were established. Moreover, thermal analysis was used to find out the degree of maximum undercooling for the graphite eutectic, Tm. A relationship was found between the eutectic cell or nodule count and the maximum undercooling Tm.. In addition it was also found that N can be related to the wall thickness of plate shaped castings. Finally, the present work provides a rational for the effect of technological factors such as the melt chemistry, inoculation practice, and holding temperature and time on the resultant cell count or nodule count of cast iron. In particular, good agreement was found between the predictions of the theoretical analysis and the experimental data.

  10. CORROSION RESISTANCE OF PEARLITIC AND BAINITIC CAST IRON IN A SYNTHETIC SOLUTION OF CONDENSED GAS FROM COMBUSTION

    Directory of Open Access Journals (Sweden)

    Sandra Matos Cordeiro Costa

    2015-03-01

    Full Text Available The corrosion of engine components of the combustion chamber is usually related to the formation of acids such as sulfuric and nitric. These acids are generated by the condensation of combustion gases that usually occur in vehicle exhaust systems. However, with the development of new technologies to reduce emissions, condensation is also being promoted in vehicle combustion chambers. This fact is associated with high exhaust gas recirculation rates, known as EGR (English term for Exhaust Gas Recirculation. Consequently, corrosion problems in the engine components are increasing, especially in cylinder liners alloy manufactured using cast iron. In this study, the corrosion resistance of two cast iron alloys, one with a pearlitic microstructure and the other with a bainite microstructure in a solution simulating the composition of the condensate obtained from the combustion gases. It was found that the microstructure of the cast iron is an important factor affecting the corrosion behavior. The results showed that none of the two materials investigated is resistant to corrosion in the test medium, and the small difference observed between the behavior of the two cast iron was related to its microstructure, which are dependent on their chemical compositions. The cast iron with a pearlitic microstructure showed less formation of corrosion products than the bainitic cast iron. This result is related to the presence of steadite phase, highly stable and resistant to corrosion in pearlitic microstructure. This phase (steadite anchors the corrosion products formed on the surface and act as a partial barrier slowing the progress of the corrosion process, that was more pronounced in the bainitic cast iron.

  11. Study of microstructure and silicon segregation in cast iron using color etching and electron microprobe analysis

    Energy Technology Data Exchange (ETDEWEB)

    Vazehrad, S., E-mail: vazehrad@kth.se [Dep. Materials Science and Engineering/Casting of Metals, Royal Institute of Technology, SE-100 44 Stockholm (Sweden); Elfsberg, J., E-mail: jessica.elfsberg@scania.com [Scania CV AB, SE-151 87 Södertälje (Sweden); Diószegi, A., E-mail: attila.dioszegi@jth.hj.se [Dep. Materials Science and Engineering/Casting of Metals, Royal Institute of Technology, SE-100 44 Stockholm (Sweden); Dep. Mechanical Engineering/Materials and Manufacturing-Foundry Technology, Jönköping University, SE-551 11 Jönköping (Sweden)

    2015-06-15

    An investigation on silicon segregation of lamellar, compacted and nodular graphite iron was carried out by applying a selective, immersion color etching and a modified electron microprobe to study the microstructure. The color etched micrographs of the investigated cast irons by revealing the austenite phase have provided data about the chronology and mechanism of microstructure formation. Moreover, electron microprobe has provided two dimensional segregation maps of silicon. A good agreement was found between the segregation profile of silicon in the color etched microstructure and the silicon maps achieved by electron microprobe analysis. However, quantitative silicon investigation was found to be more accurate than color etching results to study the size of the eutectic colonies. - Highlights: • Sensitivity of a color etchant to silicon segregation is quantitatively demonstrated. • Si segregation measurement by EMPA approved the results achieved by color etching. • Color etched micrographs provided data about solidification mechanism in cast irons. • Austenite grain boundaries were identified by measuring the local Si concentration.

  12. Study of microstructure and silicon segregation in cast iron using color etching and electron microprobe analysis

    International Nuclear Information System (INIS)

    An investigation on silicon segregation of lamellar, compacted and nodular graphite iron was carried out by applying a selective, immersion color etching and a modified electron microprobe to study the microstructure. The color etched micrographs of the investigated cast irons by revealing the austenite phase have provided data about the chronology and mechanism of microstructure formation. Moreover, electron microprobe has provided two dimensional segregation maps of silicon. A good agreement was found between the segregation profile of silicon in the color etched microstructure and the silicon maps achieved by electron microprobe analysis. However, quantitative silicon investigation was found to be more accurate than color etching results to study the size of the eutectic colonies. - Highlights: • Sensitivity of a color etchant to silicon segregation is quantitatively demonstrated. • Si segregation measurement by EMPA approved the results achieved by color etching. • Color etched micrographs provided data about solidification mechanism in cast irons. • Austenite grain boundaries were identified by measuring the local Si concentration

  13. On the Effect of Pouring Temperature on Spheroidal Graphite Cast Iron Solidification

    Directory of Open Access Journals (Sweden)

    Alex Escobar

    2015-04-01

    Full Text Available This work is focused on the effect of pouring temperature on the thermal-microstructural response of an eutectic spheroidal graphite cast iron (SGCI. To this end, experiments as well as numerical simulations were carried out. Solidification tests in a wedge-like part were cast at two different pouring temperatures. Five specific locations exhibiting distinct cooling rates along the sample were chosen for temperature measurements and metallographic analysis to obtain the number and size of graphite nodules at the end of the process. The numerical simulations were performed using a multinodular-based model. Reasonably good numerical-experimental agreements were obtained for both the cooling curves and the graphite nodule counts.

  14. A thermally coupled flow formulation with microstructural evolution for hypoeutectic cast-iron solidification

    Energy Technology Data Exchange (ETDEWEB)

    Celentano, D.; Cruchaga, M. [Univ. de Santiago de Chile (Chile)

    1999-08-01

    A thermally coupled incompressible flow formulation, including microstructural phase-change effects, is presented. The governing equations are written in the framework of the finite-element method using a generalized streamline operator technique. In particular, a hypoeutectic cast-iron microstructural model accounting for primary austenite and eutectic solidification is considered. An inverse level rule has been employed to describe the austenite formation, while the eutectic (graphite and cementite) fractions are assumed to be governed by nucleation and growth laws. The application of this methodology in the area of casting solidification constitutes an original contribution of this work. Further, an enhanced staggered scheme is also proposed in order to solve the resulting strongly coupled discretized equations. The analysis of a solidification problem, with particular interest in the influence of the natural convection on the microstructural formation, is performed. The numerical results obtained with the present formulation allow prediction of the flow patterns, volume-fraction distributions, and recalescences developed during the process.

  15. The Effects of Fracture Origin Size on Fatigue Properties of Ductile Cast Iron with Small Chill Structures

    Science.gov (United States)

    Sameshima, Daigo; Nakamura, Takashi; Horikawa, Noritaka; Oguma, Hiroyuki; Endo, Takeshi

    Reducing the weight of a machine structure is an increasingly important consideration both for the conservation of resources during production and for the energy saving during operation. With these objectives in mind, thin-walled ductile cast iron has recently been developed. Because rapid cooling could result in brittle microstructure of cementite (chill) in this cast iron, it is necessary to investigate the effect of cementite on the fatigue properties. Therefore, fatigue tests were carried out on a ductile cast iron of block castings which contained a relatively small amount of cementite. Fracture surface observation indicated that the fracture origins were located at graphite clusters and cast shrinkage porosity, not at cementite. It appears that when the size of the cementite is smaller than that of the graphite, the cementite does not affect the fatigue properties of ductile cast iron. Not surprisingly, the fatigue lives were found to increase with decrease in the size of the fatigue fracture origin. The threshold initial stress intensity factor range ΔKini,th for fatigue failure was found to be about 3-4MPa√m, independent of microstructure.

  16. Development of a ferritic ductile cast iron for improved life in exhaust applications

    OpenAIRE

    Ekström, Madeleine

    2013-01-01

    Due to coming emission legislations, the temperature is expected to increase in heavy-duty diesel engines, specifically in the hot-end of the exhaust system affecting components, such as exhaust- and turbo manifolds. Since the current material in the turbo manifold, a ductile cast iron named SiMo51, is operating close to its limits there is a need for material development in order to maintain a high durability of these components. When designing for increased life, many material properties ne...

  17. Effect of graphite degradation on the LCF properties of nodular cast iron

    Directory of Open Access Journals (Sweden)

    Denk Josef

    2014-06-01

    Full Text Available The effect of degraded microstructure on the tensile and LCF properties was studied on a casing of a turbocharger, which exhibited locally irregular graphite formation. The tensile tests showed that the ductility values of the zone with degraded graphite decreased strongly compared to the zone with normal graphite, while the strength values decreased only slightly. Based on these results and a LCF reference curve for nodular cast iron with normal graphite structure, a synthetic LCF curve was generated for the material condition with degraded graphite structure. LCF tests on specimens with irregular graphite structure confirmed the predicted LCF behaviour quite good.

  18. Study on Cracking Tendency and Mechanism of Gray Cast Iron Laser Cladding

    Institute of Scientific and Technical Information of China (English)

    YE Hong; YAN Zhong-lin; HUANG Qi; YANG Hui

    2004-01-01

    In this paper, NiCrSiB and CoWC35 powder has been used in laser cladding of gray cast iron. The cracking tendency has also been discussed. The cracks have been observed with a scan electron microscopy to analyze the cracking mechanism. The results show that cracks have not appeared in NiCrSiB cladding. Nevertheless, the cracking tendency of CoWC35 cladding is extremely high and there are both cold cracks and hot cracks in the cladding. The cracking tendency of laser cladding depends on physical properties of the cladding material and plasticity and roughness of the cladding.

  19. Study on Cracking Tendency and Mechanism of Gray Cast Iron Laser Cladding

    Institute of Scientific and Technical Information of China (English)

    YEHong; YANZhong-lin; HUANGQi; YANGHui

    2004-01-01

    In this paper, NiCrSiB and COWC35 powder has been used in laser cladding of gray cast iron. The cracking tendency has also been discussed. The cracks have been observed with a scan electron microscopy to analyze the cracking mechanism. The results show that cracks have not appeared in NiCrSiB cladding. Nevertheless, the cracking tendency of CoWC35 cladding is extremely high and there are both cold cracks and hot cracks in the cladding. The cracking tendency of laser cladding depends on physical properties of the cladding material and plasticity and roughness of the cladding.

  20. FASHION THE KITCHEN: CAST IRON STOVES THE PROVINCE OF QUEBEC, 1900-1914

    Directory of Open Access Journals (Sweden)

    Lisa Baillargeon

    2010-01-01

    Full Text Available The role of aesthetics in the marketing strategies of Quebec’s foundries and retailers at the beginning of the 20th century is not well known. This qualitative analysis of published cast iron stove advertisements suggests that the use of aesthetics to market stoves was far more elaborate than the simple alignment with trendy or classic style categories. In fact, aesthetics were the cornerstone of advertising activities aimed at developing and capitalizing on various market segments at a time of burgeoning consumerism.

  1. As cast high silicon ductile irons with optimised mechanical properties and remarkable fatigue properties

    OpenAIRE

    Torre, Urko de la; Loizaga, Aitor; Lacaze, Jacques; Sertucha, Jon

    2014-01-01

    International audience The present work shows a comparative study regarding the mechanical properties of 25 as cast ferritic ductile iron alloys, nine of them with silicon contents higher than 3·00% and carbon contents lower than 3·60%. In a first step, different carbon equivalent values have been used in order to analyse the effect of this parameter on the mechanical properties. After this comparative analysis, the composition ranges C = 3·30–3·40 wt-% and Si = 3·75–3·80 wt-% have been se...

  2. Microstructure and wear resistance of high chromium cast iron containing niobium

    OpenAIRE

    Zhang Zhiguo; Yang Chengkai; Zhang Peng

    2014-01-01

    In the paper, the effect of niobium addition on the microstructure, mechanical properties and wear resistance of high chromium cast iron has been studied. The results show that the microstructure of the heat-treated alloys is composed of M7C3 and M23C6 types primary carbide, eutectic carbide, secondary carbide and a matrix of martensite and retained austenite. NbC particles appear both inside and on the edge of the primary carbides. The hardness of the studied alloys maintains around 66 HRC, ...

  3. Effects of carbon and molybdenum on the microstructures of high chromium white cast irons

    International Nuclear Information System (INIS)

    The effects of 3 levels of carbon and 1.5% Mo addition on the solidification structures of a 15% chromium white cast iron were studied. The volume fraction of primary austenite and of eutectic carbides, as well as the number of carbide particles per unit length and the mean secondary dendrite arm spacing were measured. By means of thermal analysis, thermal arrest corresponding to the formation of the primary austenite and of the eutectic were determined. The increase in the carbon content and the addition of Mo led to lowering of the thermal arrests and to coarsening of the particles. (author)

  4. Casting and stress-strain simulations of a cast ductile iron component using microstructure based mechanical behavior

    OpenAIRE

    Olofsson, Jakob; Ingvar L. Svensson

    2012-01-01

    The industrial demand for increased component performance with concurrent reductions in component weight, development times and verifications using physical prototypes drives the need to use the full potential of casting and Finite Element Method (FEM) simulations to correctly predict the mechanical behavior of cast components in service. The mechanical behavior of the component is determined by the casting process, and factors as component geometry and casting process parameters are known to...

  5. Electron theory study on the effect of Mn on as-cast structure of Fe-C-Cr-Mn cast irons

    Institute of Scientific and Technical Information of China (English)

    SUN Zhi-ping; SHEN Bao-luo; WANG Jun; LIU Hao-huai; YANG Hong-shan; HUANG Si-jiu

    2008-01-01

    The valence electron structure of alloying austenite of 3C-15Cr high chromium White cast iron with different Mn contents from 1%to 6% is analyzed by BLD method and EET.Results shoW that the addition of Mn has major influence on the valence electron structure of the alloying austenite,especially on that of Fe-C,Fe-C-Cr and Fe-C-Cr-Mn unit cells of it.The effect becomes weak when Mn content is over 4%.Based on the effect of nA,F Dc,the weighting of each unit cell and the degree of underceoling on phase transition of the austenite,we can calculate the retained austenite content of as-cast structure of the hish chromium white cast iron.The calculation results coincide well with those of the experiment.The phase transition characters of the austenite in high chromium white cast iron can be forecasted through valence electron structure analysis of alloying austenite by BLD method and EET on the basis of Fe-C-Cr equilibrium phase diagram.

  6. A new method of fast measuring surface tension of melt cast iron and its application in graphite shape identification

    OpenAIRE

    Li, Dayong; Dequan SHI; Li, Feng

    2005-01-01

    Surface tension is one of important physical features of melt alloy. Many properties of melt alloy, such as graphite shape of cast iron and modified microstructure of aluminum alloy, can be evaluated by means of surface tension. In order to evaluate and control the melt quality in-situ melting operation, the authors advanced a new method and developed an automatic device for fast measuring surface tension of melt alloy and applied it to the practice of rapid identifying graphite shape of cast...

  7. High-Cycle Fatigue Resistance of Si-Mo Ductile Cast Iron as Affected by Temperature and Strain Rate

    Science.gov (United States)

    Matteis, Paolo; Scavino, Giorgio; Castello, Alessandro; Firrao, Donato

    2015-09-01

    Silicon-molybdenum ductile cast irons are used to fabricate exhaust manifolds of internal combustion engines of large series cars, where the maximum pointwise temperature at full engine load may be higher than 973 K (700 °C). In this application, high-temperature oxidation and thermo-mechanical fatigue (the latter being caused by the engine start and stop and by the variation of its power output) have been the subject of several studies and are well known, whereas little attention has been devoted to the high-cycle fatigue, arising from the engine vibration. Therefore, the mechanical behavior of Si-Mo cast iron is studied here by means of stress-life fatigue tests up to 10 million cycles, at temperatures gradually increasing up to 973 K (700 °C). The mechanical characterization is completed by tensile and compressive tests and ensuing fractographic examinations; the mechanical test results are correlated with the cast iron microstructure and heat treatment.

  8. Comparison of residual stresses in sand- and chill casting of ductile cast iron wind turbine main shafts

    DEFF Research Database (Denmark)

    Sonne, Mads Rostgaard; Frandsen, J. O.; Hattel, Jesper Henri

    2015-01-01

    In this work, simulations of pouring, solidification and cooling, and residual stress evolution of sand and chill cast wind turbine main shafts is performed. The models are made in the commercial software MAGMAsoft. As expected, the cooling rate of the sand casting is shown to be much lower than...... for the chill casting, resulting in a very course microstructure.From the simulations the nodule count is found to be 17 nodules per mm2 and 159 nodules permm2 for the sand and chill casting, respectively, in the critical region of the main bearing seat.This is verified from nodule counts performed on...... the real cast main shafts. Residual stressevaluations show an overall increase of the maximum principal stress field for the chill casting,which is expected. However, the stresses are found to be in compression on the surface of thechill cast main shaft, which is unforeseen....

  9. National Metal Casting Research Institute final report. Development of an automated ultrasonic inspection cell for detecting subsurface discontinuities in cast gray iron. Volume 3

    Energy Technology Data Exchange (ETDEWEB)

    Burningham, J.S. [University of Northern Iowa, Cedar Falls, IA (United States). Dept. of Industrial Technology

    1995-08-01

    This inspection cell consisted of an ultrasonic flaw detector, transducer, robot, immersion tank, computer, and software. Normal beam pulse-echo ultrasonic nondestructive testing, using the developed automated cell, was performed on 17 bosses on each rough casting. Ultrasonic transducer selection, initial inspection criteria, and ultrasonic flow detector (UFD) setup parameters were developed for the gray iron castings used in this study. The software were developed for control of the robot and UFD in real time. The software performed two main tasks: emulating the manual operation of the UFD, and evaluating the ultrasonic signatures for detecting subsurface discontinuities. A random lot of 105 castings were tested; the 100 castings that passed were returned to the manufacturer for machining into finished parts and then inspection. The other 5 castings had one boss each with ultrasonic signatures consistent with subsurface discontinuities. The cell was successful in quantifying the ultrasonic echo signatures for the existence of signature characteristics consistent with Go/NoGo criteria developed from simulated defects. Manual inspection showed that no defects in the areas inspected by the automated cell avoided detection in the 100 castings machined into finished parts. Of the 5 bosses found to have subsurface discontinuities, two were verified by manual inspection. The cell correctly classified 1782 of the 1785 bosses (99.832%) inspected.

  10. Calorimetric analysis of heating and cooling process of nodular cast iron

    Directory of Open Access Journals (Sweden)

    Bińczyk F.

    2007-01-01

    Full Text Available The study presents the results of investigations of the thermal effects which take place during heating and cooling of samples of the nodular graphite cast iron taken from the stepped test casting of the wall thicknesses amounting to 5, 10, 15 and 20 mm. For investigations, a differential scanning calorimeter, type Multi HTC S60, was used. During heating, three endothermic effects related with pearlite decomposition, phase transformation α → γ, and carbon dissolution in austenite were observed on a DSC diagram. During cooling, two exothermic effects related with phase transformation γ→ α and pearlite formation were observed to consecutively take place on a DSC diagram. The values of the enthalpy of these processes differ and depend on the initial microstructure of the examined samples. The metallic matrix in 5 mm sample after the process of heating and cooling changes totally in favour of ferrite. The same effect, though less advanced in intensity, takes place in 10 mm sample, while in 15 and 20 mm samples the matrix constitution remains unchanged. The higher is the content of ferrite in samples, the stronger is the endothermic effect of the α → γ transformation and the weaker is the endothermic effect related with carbon dissolution in austenite. The total of the endothermic effects (heating is reduced, while that of the exothermic effects (cooling increases along with the increasing thickness of walls in a stepped test casting, from which samples for the investigations were taken.

  11. Observation of Nanometric Silicon Oxide Bifilms in a Water-Atomized Hypereutectic Cast Iron Powder

    Science.gov (United States)

    Boisvert, Mathieu; Christopherson, Denis; L'Espérance, Gilles

    2016-06-01

    This study investigated the reasons for the irregular structure of primary graphite nodules that were formed in a hypereutectic cast iron powder during water atomization. The graphite nodules contain a significant amount of micron-sized pores and multiple nanometric voids that formed from silicon oxide bifilms. The bifilms theory is often used to explain the mechanisms responsible for the presence of pores in castings. However, even if many results presented in the literature tend to corroborate the existence of bifilms, to this date, only indirect evidences of their existence were presented. The observations presented in this paper are the first to show the double-sided nature of these defects. These observations support the bifilms theory and give an explanation for the presence of porosities in castings. The bifilms were used as substrate for graphite growth during solidification. The irregular structure of the graphite nodules is a consequence of the rather random structure of the bifilms that were introduced in the melt as a result of turbulences on the surface of the melt during pouring. The confirmation of the existence of bifilms can contribute to the understanding of the mechanical properties of various metallic parts.

  12. Strength distribution at interface of rotary-friction-welded aluminum to nodular cast iron

    Institute of Scientific and Technical Information of China (English)

    SONG Yu-lai; LIU Yao-hui; ZHU Xian-yong; YU Si-rong; ZHANG Ying-bo

    2008-01-01

    The morphology, size and composition of intermetallic compound at the interface of Al 1050 and nodular cast iron were studied by electron microprobe analysis(EMPA) and scan electron microscopy (SEM), respectively. The bond strength of the interface was measured by the tensile tests and the morphology of the fracture surface was observed by SEM. The observation of the interface reveals that there are two distinct morphologies: no intermetallic compound exists in the central area at the interface; while numbers of intermetallic compounds (FexAly) are formed in the peripheral area due to the overfull heat input. The tensile tests indicate that the distribution of strength in radial direction at the interface is inhomogeneous, and the central area of the interface performs greater bond strength than the peripheral area, which proves directly that the FexAly intermetallic compounds have a negative effect on the integration of interface. The morphology on the fracture surface shows that the facture in the central area at the interface has characteristic of the ductile micro-void facture. So it is important to restrain the form of the intermetallic compound to increase the bond strength of the Al 1050 and nodular cast iron by optimizing welding parameters and the geometry of components.

  13. PIXE and SPM analysis of V, Cr, Cu and Bi in nodular cast iron

    International Nuclear Information System (INIS)

    The nodular cast iron was prepared with the same nodularizing process in which the elements V, Cr, Cu and Bi were added respectively. The graphite phase was extracted from the nodular cast iron to measure the trace elements in it. It was made into a thick target and measured by proton induced X-ray emission (PIXE) analysis. The contents of V, Cr and Cu were 3, 40 and 14 ppm respectively in the graphite, as the element was separately increased to 2100, 5000 and 2500 ppm in the matrix. Therefore, V, Cr and Cu do not intrude the graphite as the contents of these elements are lower, and have no obvious effect on the nodularization. Bi, which belongs to the antinodular elements, easier intrudes into the graphite than others. The content of Bi in graphite was 74 ppm and the nodularizing rate went down by 34% when it was 200 ppm in the matrix. The distributions of V, Cr, Cu and Bi in the sample were measured using a scanning proton microprobe (SPM) to research the properties of these elements further. The results showed that most of the V, Cu and Cr distributed in the matrix. Some of the Cu intruded into the graphite, some existed in the matrix yet as Bi was increased to 200 ppm. These results of SPM agree with that of the PIXE analysis. (orig.)

  14. ELABORATION OF MANAGEMENT PLAN OF SOLID WASTE FROM SMALL CAST IRON FOUNDRIES

    Directory of Open Access Journals (Sweden)

    Carlos Alberto Mendes Moraes

    2013-12-01

    Full Text Available The foundry industry contributes to society meeting the demand of metal scrap recycling, but, at the same time, it brings a high risk of environmental impact for its many potentially pollutant wastes. Among these, there are slag and used foundry sand (cold cure molding. Through a survey about the production process of a small cast iron company, the collected data was compiled to determine the organizational setting in terms of generation and segregation of waste. From a complete environmental diagnosis carried out in eight small cast iron foundries, one of them was chosen to be a basis for the elaboration of an industrial solid waste management plan, which is becoming necessary to know and manage the generation of wastes qualitatively and quantitatively. A data assessment about the production process was carried out and compiled to determine the actual organizational scenario. As a result of that, it is possible to create a favorable environment to develop tools for environmental impacts prevention, which will permit the migration for more complex actions on the direction of more efficient process, cleaner production, and internal and external recycling of exceeding materials.

  15. Behaviour of a flake graphite cast iron under cyclic loading in tension

    International Nuclear Information System (INIS)

    A flake graphite cast iron with a tensile strength of 273 N/mm2 has been cyclically stressed between zero and various tensile stresses to study how non-elastic strains increase with the cycle number. Cycling to stress levels between 50 N/mm2 and 225 N/mm2 have been investigated over 1000 cycles or until failure occured. It has been shown that after relatively few stress cycles flake graphite cast irons stabilise and the increase in non-elastic strain per cycle reaches a constant value. This value decreases as the stress level is decreased. The results suggest that the change is non-elastic strain per cycle does not become zero until the cycling stress approaches zero and therefore the stress/strain curve may not follow a closed hysteresis loop at any stress level. The concept of a limiting stress known as the limit of accommodation is not therefore valid. For desing purposes a cycling stress at which the increase in non-elastic strain is suitable small should be considered. Increases in non-elastic strain are accompanied by corresponding decreases in modules of elasticity. (orig.) 891 RW/orig. 892 RKD

  16. Thermal cycling of cast iron surface by electron beam fusion treatment

    International Nuclear Information System (INIS)

    The technology of cast iron surface hardening, by electron beam fusion treatment, to increase the hardness and wear resistance is very well known. This method causes the great difference of hardness between a surface layer and a base material which creates the sharp structural notch. So, an attempt was made to smooth the structural notch to improve the fusion zone properties. It was decided to use here a carbon diffusion phenomenon against the temperature gradient inside the eutectic cell of ferritic cast iron with nodular graphite. To achieve the temperature gradient, the electron beam as a quasi-linear heat source was used. Owing to a very high power density of heat source and a very short interaction time, the requested temperature gradient inside the eutectic cell was obtained (at great difference of graphite and ferrite thermal properties). As a result of such treatment, a zone of pearlitic structure around the graphite as well as beneath a ledeburitic-martensitic fusion layer was attained. Hence, the significant smoothing of structural notch was obtained. (author)

  17. Mechanism of carbon influence on the transition from graphite to cementite eutectic in cast iron

    Directory of Open Access Journals (Sweden)

    E. Fraś

    2010-04-01

    Full Text Available In this work an analytical solution is used to explain mechanism of carbon influence on the transition from graphite to cementite eutectic in cast iron. It is found that this transition can be related to (1 the nucleation potential of graphite (characterized directly by the cell count, N and indirectly by nucleation coefficients Ns and b (2 the growth rate coefficient of graphite eutectic cell, (3 the temperature range, Tsc = Ts - Tc (where Ts and Tc is the equilibrium temperature of the graphite eutectic and formation temperature of the cementite eutectic respectively.and (4 the liquid volume fraction, fl after solidification of the pre-eutectic austenite. Method of estimation of Ns, b and values was presented. It has been shown that the main impact of carbon on the transition from graphite to cementite eutectic consist in increasing the eutectic cell count and growth rate of graphite eutectic cell. Analytical equations were derived to describe the absolute, CT relative chilling tendency, CTr and chill, w of cast iron.

  18. Nucleation and Growth of Graphite in Eutectic Spheroidal Cast Iron: Modeling and Testing

    Science.gov (United States)

    Carazo, Fernando D.; Dardati, Patricia M.; Celentano, Diego J.; Godoy, Luis A.

    2016-06-01

    A new model of graphite growth during the continuous cooling of eutectic spheroidal cast iron is presented in this paper. The model considers the nucleation and growth of graphite from pouring to room temperature. The microstructural model of solidification accounts for the eutectic as divorced and graphite growth rate as a function of carbon gradient at the liquid in contact with the graphite. In the solid state, the microstructural model takes into account three stages for graphite growth, namely (1) from the end of solidification to the upper bound of intercritical stable eutectoid, (2) during the intercritical stable eutectoid, and (3) from the lower bound of intercritical stable eutectoid to room temperature. The micro- and macrostructural models are coupled using a sequential multiscale approach. Numerical results for graphite fraction and size distribution are compared with experimental results obtained from a cylindrical cup, in which the graphite volumetric fraction and size distribution were obtained using the Schwartz-Saltykov approach. The agreements between the experimental and numerical results for the fraction of graphite and the size distribution of spheroids reveal the importance of numerical models in the prediction of the main aspects of graphite in spheroidal cast iron.

  19. Effect of the microhardness difference between base metal and bionic coupling unit on wear resistance of gray cast iron

    Science.gov (United States)

    Pang, Zuobo; Zhou, Hong; Chang, Fang; Zhang, Peng; Cong, Dalong; Meng, Chao; Wang, Chuanwei; Ren, Luquan

    2015-12-01

    In order to improve the wear resistance of gray cast iron guide rail, the samples with different microhardness difference between bionic coupling units and base metal were manufactured by laser surface remelting. Wear behavior of gray cast iron with bionic coupling units has been studied under dry sliding condition at room temperature using a homemade liner reciprocating wear testing machine. The wear resistance was evaluated by means of weight loss measurement and wear morphology. The results indicated that when the microhardness difference is 561 HV0.2, the wear resistance of sample is the best.

  20. Study on quantitative relation between characteristics of striature bionic coupling unit and wear resistance of gray cast iron

    Science.gov (United States)

    Pang, Zuobo; Zhou, Hong; Zhang, Peng; Cong, Dalong; Meng, Chao; Wang, Chuanwei; Ren, Luquan

    2015-03-01

    In order to improve the wear resistance of gray cast iron guide rail, striature bionic coupling units of different characteristics were manufactured by laser surface remelting. Wear behavior of gray cast iron with striature bionic coupling units has been studied under dry sliding condition at room temperature using a homemade linear reciprocating wear testing machine. The wear resistance was evaluated by means of weight loss measurement and wear morphology. The results indicated that there is a relationship between weight loss and the area of striature bionic coupling units and α: Δm = Δm0 - 0.0212S × cos α - 0.0241S × sin α.

  1. Study of carbon and silicon loss through oxidation in cast iron base metal using rotary furnace for melting

    Directory of Open Access Journals (Sweden)

    Sylvester Olanrewaju OMOLE

    2015-05-01

    Full Text Available The projection of loss of carbon and silicon through oxidation is uncertain phenomenon depending on the furnace used for melting, which affect the carbon equivalent value (CEV of cast iron produced. CEV enhances the fluidity of molten metal as well as having great effects on the mechanical properties of cast products. Study on the way elemental loss takes place during melting with rotary furnace will give idea of approach to minimize the loss. Therefore, the aim of this work is to study the magnitude of the elemental loss with rotary furnace and means to minimize the loss. 60kg of grey cast iron scrap was charged into rotary furnace of 100kg capacity after preheating the furnace for 40 minutes. Graphite and ferrosilicon was added to the charge in order to obtain a theoretical composition of not less than 4.0% carbon and 2.0% silicon. Charges in the furnace were heated to obtain molten metal which was tapped at 1400°C. Tapping was done for casting at three different times. The castings solidified in sand mould and allowed to cool to room temperature in the mould. Castings were denoted as sample 1, 2 and 3. Final compositions of each casting were analyzed with optical light emission spectrometer. Sample 1 has 2.95% carbon and 1.82% silicon. Sample 2 has 2.88% carbon and 1.70% silicon and sample 3 has 2.75% carbon and 1.63% silicon.

  2. Corrosion Inhibiting Mechanism of Nitrite Ion on the Passivation of Carbon Steel and Ductile Cast Iron for Nuclear Power Plants

    Directory of Open Access Journals (Sweden)

    K. T. Kim

    2015-01-01

    Full Text Available While NaNO2 addition can greatly inhibit the corrosion of carbon steel and ductile cast iron, in order to improve the similar corrosion resistance, ca. 100 times more NaNO2 addition is needed for ductile cast iron compared to carbon steel. A corrosion and inhibition mechanism is proposed whereby NO2- ion is added to oxidize. The NO2- ion can be reduced to nitrogen compounds and these compounds may be absorbed on the surface of graphite. Therefore, since nitrite ion needs to oxidize the surface of matrix and needs to passivate the galvanic corroded area and since it is absorbed on the surface of graphite, a greater amount of corrosion inhibitor needs to be added to ductile cast iron compared to carbon steel. The passive film of carbon steel and ductile cast iron, formed by NaNO2 addition showed N-type semiconductive properties and its resistance, is increased; the passive current density is thus decreased and the corrosion rate is then lowered. In addition, the film is mainly composed of iron oxide due to the oxidation by NO2- ion; however, regardless of the alloys, nitrogen compounds (not nitrite were detected at the outermost surface but were not incorporated in the inner oxide.

  3. The Influence Of Temperature Gradient On Stereological Parameters Of Carbide Phase On Cross-Section Of Abrasive Wear Resistant Chromium Cast Iron

    Directory of Open Access Journals (Sweden)

    Studnicki A.

    2015-09-01

    Full Text Available In the paper analysis of temperature gradient and parameters of structure on casting cross-section of abrasive wear resistant chromium cast iron at carbon content of 2,5%wt. and chromium 17%wt. with nickel and molybdenum additives are presented. The castings were made with use of special tester ϕ100mm (method of temperature gradient and derivative analysis with temperature recording in many points from thermal centre to surface (to mould of casting. Registered cooling curves were used to describe the temperature gradient on cross-section of analyzed casting. On the basis of determined curves of temperature gradient measurement fields were selected to make the quantitative studies of structure. The results of studies show significant influence of temperature gradient on quantitative parameters of chromium cast iron structure. Moreover was affirmed that exists a critical temperature gradient for which is present rapid change of quantitative parameters of chromium cast iron structure.

  4. Influence of wall thickness of spheroidal cast iron, manufactured in the foundry METAL-ODLEW Sp.J., on its graphite shape index and ultrasonic control index

    Directory of Open Access Journals (Sweden)

    W. Orłowicz

    2009-07-01

    Full Text Available This work presents the results of ultrasonic evaluation of the microstructure of spheroidal cast iron manufactured under production condi-tions at the foundry of Metal Odlew Sp.J. Evaluation of ultrasonic control index sensitiveness to changes of graphite shape index Ss of spheroidal cast iron (type 500-7, utilized modelled stepped castings. The relationship was determined between the shape index of graphite precipitation Ss and the velocity of longitudinal ultrasonic wave cL.

  5. Influence of wall thickness of spheroidal cast iron, manufactured in the foundry METAL-ODLEW Sp.J., on its graphite shape index and ultrasonic control index

    OpenAIRE

    W. Orłowicz; M. Tupaj; M. Mróz; E. Guzik; J. Nykiel; A. Zając; B. Piotrowski

    2009-01-01

    This work presents the results of ultrasonic evaluation of the microstructure of spheroidal cast iron manufactured under production condi-tions at the foundry of Metal Odlew Sp.J. Evaluation of ultrasonic control index sensitiveness to changes of graphite shape index Ss of spheroidal cast iron (type 500-7), utilized modelled stepped castings. The relationship was determined between the shape index of graphite precipitation Ss and the velocity of longitudinal ultrasonic wave cL.

  6. Effect of austempering parameters on microstructure and mechanical properties of horizontal continuous casting ductile iron dense bars

    OpenAIRE

    Chun-jie Xu; Pan Dai; Zheng-yang Zhang

    2015-01-01

    In the present research, the orthogonal experiment was carried out to investigate the influence of different austempering process parameters (i.e. austenitizing temperature and time, and austempering temperature and time) on microstructure and mechanical properties of LZQT500-7 ductile iron dense bars with 172 mm in diameter which were produced by horizontal continuous casting (HCC). The results show that the major factors influencing the hardness of austempered ductile iron (ADI) are austeni...

  7. Machinability of Austempered Ductile Iron (ADI) Produced by Integrated Green Technology of Continuous Casting-Heat Treatment Processes

    Science.gov (United States)

    Meena, A.; El Mansori, M.; Ghidossi, P.

    2011-01-01

    This study presents the novel processing technique known as continuous casting-heat treatment processes to produce Austempered Ductile Iron (ADI) which is a new class of ductile iron. ADI is characterized by improved mechanical properties but has low machinability as compared to other cast irons and steel of similar strength. The novel technique is developed by the integration of casting (in die casting) and heat treatment processes in foundry to save cost energy and time. Specimens just after casting were austenitized at 930° C for 90 min and then austempered in fluidized bed at 380° C for 90 and 120 min. Hence, the effect of austempering time on the morphology of retained austenite and mechanical properties of the material were examined and compared with conventionally produced ADI. Drilling tests were then carried out to evaluate the machinability of ADI in terms of cutting forces, chip micro-hardness, chip morphology and surface roughness. The mechanical properties of ADI austempered for 120 min have found to be better as compare to the ADI austempered for 90 min.

  8. Analysis and simulation of chromium-molybdenum cast iron's crystallization with use of thermal-derivative analysis

    International Nuclear Information System (INIS)

    An analysis of crystallization of chromium-molybdenum cast iron with use of the TDA - method is presented in the paper. It has been found that for the cast iron under investigation the eutectic M23C6 + γ is crystallizing independently of M3C + γ. It has been shown that when increasing the Mo concentration in the cast iron from 2.0 wt.% to 4.0 wt.% the heat being transferred to surrounding due to crystallization (h.t.s.c.) of a primary austenite, of the eutectic M23C6 + γ and the one of the phase transformation austenite → perlite are increasing as well, while the heat being transferred to surrounding due to crystallization of the eutectic M3C +γ is decreasing. It has been found as well that the result of the simulation of the crystallization of the cast iron are in good correspondence to the experimental TDA - curves as well as to the flux of the heat being transferred to surrounding due to crystallization. (author)

  9. Hot Corrosion Behavior of High-Chromium, High-Carbon Cast Irons in NaCl-KCl Molten Salts

    Directory of Open Access Journals (Sweden)

    S. Vuelvas-Rayo

    2012-01-01

    Full Text Available A study on the corrosion behavior of a series of experimental high-chromium (18.53–30.48 wt.%, high-carbon (3.82–5.17% cast irons in NaCl-KCl (1 : 1 M at 670°C has been evaluated by using weight loss technique and compared with a 304-type stainless steel. It was found that all castings had a higher corrosion rate than conventional 304SS and that the addition of Cr increased the degradation rate of the cast irons. Additionally, corrosion rate increased by increasing the C contents up to 4.29%, but it decreased with a further increase in its contents. Results are discussed in terms of consumption of the Cr2O3 layer by the melt.

  10. Numerical Simulation of Austempering Heat Treatment of a Ductile Cast Iron

    Science.gov (United States)

    Boccardo, Adrián D.; Dardati, Patricia M.; Celentano, Diego J.; Godoy, Luis A.; Górny, Marcin; Tyrała, Edward

    2016-02-01

    This paper presents a coupled thermo-mechanical-metallurgical formulation to predict the dimensional changes and microstructure of a ductile cast iron part as a consequence of an austempering heat process. To take into account the different complex phenomena which are present in the process, the stress-strain law and plastic evolution equations are defined within the context of the associate rate-independent thermo-plasticity theory. The metallurgical model considers the reverse eutectoid, ausferritic, and martensitic transformations using macro- and micro-models. The resulting model is solved using the finite element method. The performance of this model is evaluated by comparison with experimental results of a dilatometric test. The results indicate that both the experimental evolution of deformation and temperature are well represented by the numerical model.

  11. SPHERICAL MICROSTRUCTURE FORMATION OF THE SEMI-SOLID HIGH CHROMIUM CAST IRON Cr20Mo2

    Institute of Scientific and Technical Information of China (English)

    W.M. Mao; A.M. Zhao; X.Y. Zhong

    2004-01-01

    The nondendritic semi-solid slurry preparation of high chromium cast iron Cr20Mo2 has been studied in this paper. The experiments show that the proeutectic austenitic particles are more spherical under a larger stirring power condition, even if the stirring time is shorter, while the proeutectic austenitic particles are not very much spherical under a smaller stirring power condition and some proeutectic austenitic dendrites also exist, even if the stirring time is very long. The experiments also show that when stirred for 5 6 minutes under the test condition, the semi-solid slurry with 40vol. %-50vol. % solid fraction and spherical proeutectic austenite in the size of 50-80μm can be obtained.

  12. PERFORMANCE STUDY OF CRYO TREATED HSS DRILLS IN DRILLING CAST IRON

    Directory of Open Access Journals (Sweden)

    B.R. Ramji

    2010-07-01

    Full Text Available The objective of this research was to study the performance of cryogenically treated HSS drills for drilling gray cast iron. The thrust force and torque were measured using drill tool dynamometer. The surface roughness (Ra, Rz, Rq and Rt of the drilled specimens were measured using talysurf. The experimental lay-out was designedusing Taguchi’s Orthogonal Array technique. Signal-to-Noise Ratio analysis was performed to identify the effect of the parameters on the response variables. The treated drills were found superior to the non-treated in all the test conditions in terms of lesser thrust force, torque and also superior surface roughness of the specimens.The tool wear was studied using SEM. FEM was done to predict tool tip temperature.

  13. ANALYSIS OF FORCES, ROUGHNESS, WEAR AND TEMPERATURE IN TURNING CAST IRON USING CRYOTREATED CARBIDE INSERTS

    Directory of Open Access Journals (Sweden)

    B.R. Ramji,

    2010-07-01

    Full Text Available The aim of this research was to examine the effect of cryogenic treatment of the coated carbide inserts on their performance in turning gray cast iron work pieces. The cryogenic treatment cycle consisted of cooling the test samples from room temperature to cryogenic temperature of -178.9 C in three hours, soaking at cryogenictemperature around 24 hours and warming to room temperature in about five hours. Cutting forces, surface roughness, flank wear and tool tip temperature were studied for both coated and coated-treated inserts. ANOVA was performed to identify the effect of the parameters on the response variables. Cryogenically treated inserts proved superior to the non-treated in all the test conditions in terms of lesser flank wear of the inserts and reduced surface roughness of the specimens. The after turned inserts were examined using Scanning Electron Microscopy for studying the flank wear mechanism.

  14. Microstructure and wear resistance of high chromium cast iron containing niobium

    Institute of Scientific and Technical Information of China (English)

    Zhang Zhiguo; Yang Chengkai; Zhang Peng; Li Wei

    2014-01-01

    In the paper, the effect of niobium addition on the microstructure, mechanical properties and wear resistance of high chromium cast iron has been studied. The results show that the microstructure of the heat-treated aloys is composed of M7C3 and M23C6 types primary carbide, eutectic carbide, secondary carbide and a matrix of martensite and retained austenite. NbC particles appear both inside and on the edge of the primary carbides. The hardness of the studied alloys maintains around 66 HRC, not significantly affected by the Nb content within the selected range of 0.48%-0.74%. The impact toughness of the aloys increases with increasing niobium content. The wear resistance of the specimens presents little variation in spite of the increase of Nb content under a light load of 40 N. However, when heavier loads of 70 and 100 N are applied, the wear resistance increases with increasing Nb content.

  15. Microstructure and wear resistance of high chromium cast iron containing niobium

    Directory of Open Access Journals (Sweden)

    Zhang Zhiguo

    2014-05-01

    Full Text Available In the paper, the effect of niobium addition on the microstructure, mechanical properties and wear resistance of high chromium cast iron has been studied. The results show that the microstructure of the heat-treated alloys is composed of M7C3 and M23C6 types primary carbide, eutectic carbide, secondary carbide and a matrix of martensite and retained austenite. NbC particles appear both inside and on the edge of the primary carbides. The hardness of the studied alloys maintains around 66 HRC, not significantly affected by the Nb content within the selected range of 0.48%-0.74%. The impact toughness of the alloys increases with increasing niobium content. The wear resistance of the specimens presents little variation in spite of the increase of Nb content under a light load of 40 N. However, when heavier loads of 70 and 100 N are applied, the wear resistance increases with increasing Nb content.

  16. Influences of single laser tracks' space on the rolling fatigue contact of gray cast iron

    Science.gov (United States)

    Chen, Zhi-kai; Zhou, Ti; Zhang, Peng; Zhang, Hai-feng; Yang, Wan-shi; Zhou, Hong; Ren, Lu-quan

    2015-09-01

    To improve the fatigue wear resistance of gray cast iron, the surface is modified by Nd:YAG laser to imitate the unique surface of soil creatures (alternative soft and hard phases). After laser treatment, the remelting region is the named unit which is mainly characterized of compact and refinement grains. In the present work, the influence of the unit space on the fatigue wear resistance is experimentally studied. The optimum space is proven to be 2 mm according to the tested results and two kinds of delamination are observed on samples' worn surface. Subsequently, the mechanisms of fatigue wear resistance improvement are suggested: (i) for microscopic behavior, the bionic unit not only delays the initiation of microcracks, but also significantly obstructs the propagation of cracks; (ii) for macroscopic behavior, the hard phase resists the deformation and the soft phase releases the deformation.

  17. TECHNICAL CONDITION OF HIGH-STRENGTH CAST IRON CRANKSHAFTS FROM AND MATERIAL SELECTION FOR THEIR RESTORATION

    Directory of Open Access Journals (Sweden)

    T. Vigerina

    2013-01-01

    Full Text Available The paper presents data on a technical condition of cast iron crankshafts to be repaired which is characterized by wear of crankshaft necks and connecting rod journals and misalignment of crankshaft  necks of ZMZ-53-engines. Wear and misalignment of crankshaft necks are closely described by the the Weibull's law and 70–75 % of the shafts to be repaired require recovery with deposition of coating. In order to recover crankshaft necks it is proposed to apply plasma spraying with a mixture of powders which includes copper powder. Coating obtained in accordance with the proposed technology is characterized by wear intensity during its normal operation 4,0 · 10–6 g/m, and it is by 3–5 % lower than the wear intensity rate of those shafts that have been recovered with the help of spraying powder mixtures without copper.

  18. Damaging micromechanisms characterization in a ferritic-pearlitic ductile cast iron

    Directory of Open Access Journals (Sweden)

    Vittorio Di Cocco

    2014-10-01

    Full Text Available The analysis of the damaging micromechanisms in Ductile Cast Irons is often focused on ferritic matrix. Up to ten years ago, for this grades of DCIs, the main damaging micromechanism was identified with the graphite elements – ferritic matrix debonding. More recent experimental results showed the presence of an internal gradient of mechanical properties in the graphite elements and the importance of other damaging micromechanisms, with a negligible importance of the graphite elements – ferritic matrix debonding mechanism. In this work, damaging micromechanisms development in a ferritic – pearlitic DCI have been investigated by means of tensile tests performed on mini-tensile specimens and observing the specimens lateral surfaces by means of a scanning electro microscope (SEM during the tests (“in-situ” tests. Experimental results have been compared with the damaging micromechanisms observed in fully ferritic and fully pearlitic DCIs.

  19. Effect of cerium modification on microstructure and properties of hypereutectic high chromium cast iron

    Energy Technology Data Exchange (ETDEWEB)

    Zhi, Xiaohui, E-mail: mkmkzxh@hotmail.com [School of Mechanical Engineering, Shijiazhuang Tiedao University, Shijiazhuang 050043, Hebei Province (China); Liu, Jinzhi [School of Mechanical Engineering, Shijiazhuang Tiedao University, Shijiazhuang 050043, Hebei Province (China); Xing, Jiandong; Ma, Shengqiang [State Key Laboratory Mechanical Behavior of Materials, School of Materials Science and Engineering, Xi' an Jiaotong University, Xi' an 710049, Shaanxi Province (China)

    2014-05-01

    The effect of cerium modification on the microstructure and properties of hypereutectic high chromium cast iron primarily containing 4.0 wt% C and 20.0 wt% Cr was studied by means of optical microscopy, transmission electron microscope, scanning electron microscope, and energy dispersive X-ray spectrometry. The primary M{sub 7}C{sub 3} carbides were refined obviously when cerium was added in the melt. Ce{sub 2}S{sub 3} was found in the primary M{sub 7}C{sub 3} carbides and acted as the heterogeneous substrate of M{sub 7}C{sub 3} carbides. The impact toughness of the specimen modified with 0.5 wt% cerium increased by 50% compared with the specimen without cerium modification. The hardness of the alloy modified with cerium increased slightly compared with the specimen without cerium modification.

  20. Laser Surface Remelting of Medium Ni-Cr Infinite Chilling Cast Iron Roll

    Institute of Scientific and Technical Information of China (English)

    YAOJian-hua; ZHANGQun-li; XIESong-jing

    2004-01-01

    Laser surface remelting of medium Ni-Cr infinite chilling cast iron was performed with a continuous wave CO2 laser beam with the power of 7 KW under the argon shielding. The microstructural analysis of the laser remelted layer by optical microscope shows that the laser remelted layer consists of three zones, which is the melting zone, the transition zone and the heat affected zone. The size of the dendrite of the melting zone is only in the 1/10 to 1/30 range of that of the substrate. The distribution of the hardness of the laser remelted layer was detected, and the carrying capacity of rolling steel was also field-tested. The results show that both the hardness of the remelted layer and the carrying capacity all increase, especially, the carrying capacity was 50% increased compared with the substrate.

  1. Laser Surface Remelting of Medium Ni-Cr Infinite Chilling Cast Iron Roll

    Institute of Scientific and Technical Information of China (English)

    YAO Jian-hua; ZHANG Qun-li; XIE Song-jing

    2004-01-01

    Laser surface remelting of medium Ni-Cr infinite chilling cast iron was performed with a continuous wave CO2 laser beam with the power of 7 KW under the argon shielding. The microstructural analysis of the laser remelted layer by optical microscope shows that the laser remelted layer consists of three zones, which is the melting zone, the transition zone and the heat affected zone. The size of the dendrite of the melting zone is only in the 1/10 to 1/30 range of that of the substrate. The distribution of the hardness of the laser remelted layer was detected, and the carrying capacity of rolling steel was also field-tested. The results show that both the hardness of the remelted layer and the carrying capacity all increase,especially, the carrying capacity was 50% increased compared with the substrate.

  2. 3D quantitative analysis of graphite morphology in high strength cast iron by high-energy X-ray tomography

    International Nuclear Information System (INIS)

    The size and morphology of the graphite particles play a crucial role in determining various mechanical and thermal properties of cast iron. In the present study, we utilized high-energy synchrotron X-ray tomography to perform quantitative 3D-characterization of the distribution of graphite particles in high-strength compacted graphite iron (CGI). The size, shape, and spatial connectivity of graphite were examined. The analysis reveals that the compacted graphite can grow with a coral-tree-like morphology and span several hundred microns in the iron matrix

  3. Microstructure and properties of Ti–Nb–V–Mo-alloyed high chromium cast iron

    Indian Academy of Sciences (India)

    Youping Ma; Xiulan Li; Yugao Liu; Shuyi Zhou; Xiaoming Dang

    2013-10-01

    The correlations of microstructure, hardness and fracture toughness of high chromium cast iron with the addition of alloys (titanium, vanadium, niobium and molybdenum) were investigated. The results indicated that the as-cast microstructure changed from hypereutectic, eutectic to hypoeutectic with the increase of alloy contents. Mo dissolved in austenite and increased the hardness by solid solution strengthening. TiC and NbC mainly existed in austenite and impeded the austenite dendrite development. V existed in multicomponent systems in forms of V alloy compounds (VCrFe8 and VCr2C2).With the increase of alloy additions, carbides size changed gradually from refinement to coarseness, hardness and impact toughness were increased and then decreased. Compared with the fracture toughness (6 J/cm2) and hardness (50.8HRC) without any alloy addition, the toughness and hardness at 0.60 V–0.60Ti–0.60Nb–0.35Mo (wt%) additions were improved and achieved to 11 J/cm2 and 58.9HRC, respectively. The synergistic roles of Ti, Nb, V and Mo influenced the solidification behaviour of alloy. The refinement of microstructure and improvement of carbides morphologies, size and distribution improved the impact toughness.

  4. A Journey across Multidirectional Connections: Linda Grant’s The Cast Iron Shore

    Directory of Open Access Journals (Sweden)

    Silvia Pellicer-Ortín

    2015-10-01

    Full Text Available Among the numerous groups that have negotiated their fragmented identities through various literary practices in the last few decades, the Jewish collective has come to symbolize the epitome of diaspora and homelessness. In particular, British-Jewish writers have recently started to reconstruct their fragmented memories through writing. This is an extremely interesting phenomenon in the case of those Jewish women who are fiercely struggling to find some sense of personhood as Jewish, British, female, immigrant subjects. Linda Grant’s novel The Cast Iron Shore will be analyzed so as to unveil the narrative mechanisms through which many of the identity tensions experienced by contemporary Jewish women are exhibited. The different stages in the main character’s journey will be examined by drawing on theories on the construction of Jewish identity and femininity, and by applying the model of multidirectional memory fostered by various contemporary thinkers such as Michael Rothberg, Stef Craps, Max Silverman, and Bryan Cheyette. The main claim to be demonstrated is that this narration links the (histories of oppression and racism endured both by the Jewish and the Black communities in order to make the protagonist encounter the Other, develop her mature political self, and liberate her mind from rigid religious, patriarchal, and racial stereotypes. The Cast Iron Shore becomes, then, a successful attempt to demonstrate that the (histories of displacement endured by divergent communities during the twentieth century are connected, and it is the establishment of these connections that can help contemporary Jewish subjects to claim new notions of their personhood in the public sphere.

  5. High-temperature low cycle fatigue behavior of a gray cast iron

    International Nuclear Information System (INIS)

    The strain controlled low cycle fatigue properties of the studied gray cast iron for engine cylinder blocks were investigated. At the same total strain amplitude, the low cycle fatigue life of the studied material at 523 K was higher than that at 423 K. The fatigue behavior of the studied material was characterized as cyclic softening at any given total strain amplitude (0.12%–0.24%), which was attributed to fatigue crack initiation and propagation. Moreover, this material exhibited asymmetric hysteresis loops due to the presence of the graphite lamellas. Transmission electron microscopy analysis suggested that cyclic softening was also caused by the interactions of dislocations at 423 K, such as cell structure in ferrite, whereas cyclic softening was related to subgrain boundaries and dislocation climbing at 523 K. Micro-analysis of specimen fracture appearance was conducted in order to obtain the fracture characteristics and crack paths for different strain amplitudes. It showed that the higher the temperature, the rougher the crack face of the examined gray cast iron at the same total strain amplitude. Additionally, the microcracks were readily blunted during growth inside the pearlite matrix at 423 K, whereas the microcracks could easily pass through pearlite matrix along with deflection at 523 K. The results of fatigue experiments consistently showed that fatigue damage for the studied material at 423 K was lower than that at 523 K under any given total strain amplitude. - Highlights: • The low cycle fatigue behavior of the HT250 for engine cylinder blocks was investigated. • TEM investigations were conducted to explain the cyclic deformation response. • The low cycle fatigue cracks of HT250 GCI were studied by SEM. • The fatigue life of the examined material at 523 K is higher than that at 423 K

  6. Combination of microscopic model and VoF-multiphase approach for numerical simulation of nodular cast iron solidification

    Science.gov (United States)

    Subasic, E.; Huang, C.; Jakumeit, J.; Hediger, F.

    2015-06-01

    The ongoing increase in the size and capacity of state-of-the-art wind power plants is highlighting the need to reduce the weight of critical components, such as hubs, main shaft bearing housings, gear box housings and support bases. These components are manufactured as nodular iron castings (spheroid graphite iron, or SGI). A weight reduction of up to 20% is achievable by optimizing the geometry to minimize volume, thus enabling significant downsizing of wind power plants. One method for enhancing quality control in the production of thick-walled SGI castings, and thus reducing tolerances and, consequently, enabling castings of smaller volume is via a casting simulation of mould filling and solidification based on a combination of microscopic model and VoF-multiphase approach. Coupled fluid flow with heat transport and phase transformation kinetics during solidification is described by partial differential equations and solved using the finite volume method. The flow of multiple phases is described using a volume of fluid approach. Mass conservation equations are solved separately for both liquid and solid phases. At the micro-level, the diffusion-controlled growth model for grey iron eutectic grains by Wetterfall et al. is combined with a growth model for white iron eutectic grains. The micro-solidification model is coupled with macro-transport equations via source terms in the energy and continuity equations. As a first step the methodology was applied to a simple geometry to investigate the impact of mould-filling on the grey-to-white transition prediction in nodular cast iron.

  7. Influence of rare earth nanoparticles and inoculants on performance and microstructure of high chromium cast iron

    Institute of Scientific and Technical Information of China (English)

    HOU Yuncheng; WANG You; PAN Zhaoyi; YU Lili

    2012-01-01

    The high chromium cast irons (HCCIs) with rare earth (RE) nanoparticles or inoculants were fabricated in the casting process.The phase compositions and microstructure were analyzed by X-ray diffraction (XRD) and optical microscopy (OM),respectively.The hardness and impact toughness were tested by Rockwel-hardmeter and impacting test enginery.And then,the morphology of fracture was researched by scanning electron microscopy (SEM).The results demonstrated that the phase compositions of HCCIs with addition of RE nanoparticles or inoculants which were M7C3 carbides + α -Fe did not change obviously.However,the prime M7C3 carbides morphology had great changes with the increase of RE nanoparticles,which changed from long lath to granular or island shape.When the content of RE nanoparticles was 0.4 wt.%,the microstructure of high chromium cast iron was refined greatly.The microstructure of carbides was coarser when the addition of RE nanoparticles was higher than 0.4 wt.%.The hardness and impact toughness of HCCIs were improved by addition of RE nanoparticles or inoculants.The impact toughness of HCCIs was increased 36.4% with RE nanoparticles of 0.4 wt.%,but the hardness changed slightly.In addition,the adding of RE nanoparticles or inoculants could reduce the degree of the brittle fracture.Fracture never seemed regular,instead,containing lots of laminates and dimples with the increase of the RE nanoparticles.The results also indicated that the optimal addition amonnt of the RE nanoparticles was 0.4%,under this composition,the microstructure and mechanical property achieved the best cooperation.In addition,through the study of erosion wear rate,when adding 0.4% RE nanoparticles into the HCCIs,the erosion wear rate got the minimum 0.32×10-3 g/mm2,which could increase 51.5% compared with that without any RE nanoparticles.

  8. Galvanic corrosion of copper-cast iron couples in relation to the Swedish radioactive waste canister concept

    International Nuclear Information System (INIS)

    To ensure the safe encapsulation of spent nuclear fuel rods for geological disposal, SKB are considering using the Copper-Iron Canister, which consists of an outer copper canister and an inner cast iron container. The canister will be placed into boreholes in the bedrock of a geologic repository and surrounded by bentonite clay. In the unlikely event of the outer copper canister being breached, water could enter the annulus between the inner and outer canister and at points of contact between the two metals there would be a possibility of galvanic interactions. To study this effect, copper-cast iron galvanic couples were set up in a number of different environments representing possible conditions in the SKB repository. The tests investigated two artificial pore-waters and a bentonite slurry, under aerated and deaerated conditions, at 30 deg. C and 50 deg. C. The currents passing between the coupled electrodes and the potential of the couples were monitored for several months. In addition, some bimetallic crevice specimens based on the multi-crevice assembly (MCA) design were used to simulate the situation where the copper canister will be in direct contact with the cast iron inner vessel. The effect of growing an oxide film on the surface of the cast iron prior to coupling it with copper was also investigated. The electrochemical results are presented graphically in the form of electrode potentials and galvanic corrosion currents as a function of time. The galvanic currents in aerated conditions were much higher than in deaerated conditions. For example, at 30 deg. C, galvanic corrosion rates as low as 0.02 μm/year were observed for iron in groundwater after de-aeration, but of the order of 100 μm/year for the cast iron at 50 deg. C in the presence of oxygen. The galvanic currents were generally higher at 50 deg. C than at 30 deg. C. None of the MCA specimens exhibited any signs of crevice corrosion under deaerated conditions. It will be shown that in deaerated

  9. Erosive Wear Behavior of High-Alloy Cast Iron and Duplex Stainless Steel under Mining Conditions

    Science.gov (United States)

    Yoganandh, J.; Natarajan, S.; Kumaresh Babu, S. P.

    2015-09-01

    Centrifugal pumps used in the lignite mines encounter erosive wear problems, leading to a disastrous failure of the pump casings. This paper attempts to evaluate the erosive wear resistance of Ni-Hard 4, high-chromium iron, and Cast CD4MCu duplex stainless steel (DSS), for mining conditions. The prepared test coupons were subjected to an erosion test by varying the impingement velocity and the angle of impingement, under two different pH conditions of 3 and 7, which pertained to the mining conditions. XRD analysis was carried out to confirm the phases present in the alloy. The eroded surface was subjected to SEM analysis to identify the erosion mechanisms. The surface degradation of Ni-Hard 4 and high-chromium iron came from a low-angle abrasion with a grooving and plowing mechanism at a low angle of impingement. At normal impingement, deep indentations resulted in lips and crater formations, leading to degradation of the surface in a brittle manner. A combined extrusion-forging mechanism is observed in the CD4MCu DSS surface at all the impingement angles.

  10. Emission of organic compounds from mould and core binders used for casting iron, aluminium and bronze in sand moulds

    DEFF Research Database (Denmark)

    Tiedje, Niels Skat; Crepaz, Rudolf; Eggert, Torben; Bey, Niki

    2010-01-01

    compositions were tested. A test method that provides uniform test conditions is described. The method can be used as general test method to analyse off gasses from binders. Moulds containing a standard size casting were produced and the amount and type of organic compounds resulting from thermal degradation...... of binders was monitored when cast iron, bronze and aluminium was poured in the moulds. Binder degradation was measured by collecting off gasses in a specially designed ventilation hood at a constant flow rate. Samples were taken from the ventilation system and analysed for hydrocarbons and CO...

  11. A study on the structure and mechanical properties of vermicular cast iron with pearlitic-ferritic matrix

    Directory of Open Access Journals (Sweden)

    E. Guzik

    2009-07-01

    Full Text Available The results of studies on the use of magnesium alloy in modern cored wire injection method for production of vermicular graphite cast irons were described. The injection of Mg cored wire length is a treatment method which can be used to process iron melted in an electric induction furnace. This paper describes the results of using a high-magnesium ferrosilicon alloy in cored wire (Mg recovery 45% for the production of vermicular graphite cast irons at Giesserei Heunisch GmbH Foundry with the pearlite matrix with about 20%ferrite content. The results of calculations and experiments have indicated the length of the cored wire to be injected basing on the initial sulfur content and weight of the treated melt. The paper presents a microstructure matrix and vermicular graphite in standard sample and different walled castings. The results of numerous trials have shown that the magnesium cored wire process can produce high quality vermicular graphite irons under the specific industrial conditions of the above mentioned foundries.

  12. Corrosion inhibition of Eleusine aegyptiaca and Croton rottleri leaf extracts on cast iron surface in 1 M HCl medium

    Energy Technology Data Exchange (ETDEWEB)

    Rajeswari, Velayutham [Department of Chemistry, Periyar University, Salem 636011 (India); Kesavan, Devarayan [Department of Chemistry, Dhirajlal Gandhi College of Technology, Salem 636309 (India); Gopiraman, Mayakrishnan [Department of Chemistry, National Institute of Technology, Tiruchirappalli 620015 (India); Viswanathamurthi, Periasamy, E-mail: viswanathamurthi72@gmail.com [Department of Chemistry, Periyar University, Salem 636011 (India); Poonkuzhali, Kaliyaperumal; Palvannan, Thayumanavan [Department of Bio-Chemistry, Periyar University, Salem 636011 (India)

    2014-09-30

    Graphical abstract: - Highlights: • Eleusine aegyptiaca and Croton rottleri are commonly available, less-toxic and eco-friendly inhibitors for cast iron corrosion. • The active constituents present in extracts adsorbed on the iron surface to inhibit the acidic corrosion. • The higher values of E{sub a} and ΔH{sup *} point out the higher inhibition efficiency noticed for the inhibitors. • Weight loss methods at various temperature and spectral data provides evidence for adsorption mechanism of inhibitors. - Abstract: The adsorption and corrosion inhibition activities of Eleusine aegyptiaca (E. aegyptiaca) and Croton rottleri (C. rottleri) leaf extracts on cast iron corrosion in 1 M hydrochloric acid solution were studied first time by weight loss and electrochemical techniques viz., Tafel polarization and electrochemical impedance spectroscopy. The results obtained from the weight loss and electrochemical methods showed that the inhibition efficiency increased with inhibitor concentrations. It was found that the extracts acted as mixed-type inhibitors. The addition of halide additives (KCl, KBr, and KI) on the inhibition efficiency has also been investigated. The adsorption of the inhibitors on cast iron surface both in the presence and absence of halides follows the Langmuir adsorption isotherm model. The inhibiting nature of the inhibitors was supported by FT-IR, UV–vis, Wide-angle X-ray diffraction and SEM methods.

  13. SEALING LARGE-DIAMETER CAST-IRON PIPE JOINTS UNDER LIVE CONDITIONS

    Energy Technology Data Exchange (ETDEWEB)

    Kiran M. Kothari; Gerard T. Pittard

    2003-01-01

    Utilities in the U.S. operate over 75,000 km (47,000 miles) of old cast-iron pipes for gas distribution. The bell-and-spigot joints tend to leak as these pipes age. Current repair practices are costly and highly disruptive. The objective of this program is to design, test and commercialize a robotic system capable of sealing multiple cast-iron bell and spigot joints from a single pipe entry point. The proposed system will perform repairs while the pipe remains in service by traveling through the pipe, cleaning each joint surface, and attaching a stainless-steel sleeve lined with an epoxy-impregnated felt across the joint. This approach will save considerable time and labor, avoid traffic disruption, and eliminate any requirement to interrupt service (which results in enormous expense to utilities). Technical challenges include: (1) repair sleeves must compensate for diametric variation and eccentricity of cast-iron pipes; (2) the assembly must travel long distances through pipes containing debris; (3) the pipe wall must be effectively cleaned in the immediate area of the joint to assure good bonding of the sleeve; and (4) an innovative bolt-on entry fitting is required to conduct repair operations on live mains. The development effort is divided into eleven tasks. Task 1--Program Management was previously completed. Two reports, one describing the program management plan and the other consisting of the technology assessment, were submitted to the DOE COR in the first quarter. Task 2--Establishment of Detailed Design Specifications and Task 3--Design and Fabricate Ratcheting Stainless-Steel Repair Sleeves are now well underway. First-quarter activities included conducting detailed analyses to determine the capabilities of coiled-tubing locomotion for entering and repairing gas mains and the first design iteration of the joint-sealing sleeve. The maximum horizontal reach of coiled tubing inside a pipeline before buckling prevents further access was calculated for a

  14. A study of anti-nodulizing properties of Pb, Bi, Al and Ti in nodular cast iron by SPM

    International Nuclear Information System (INIS)

    The nodular cast iron samples are prepared with the normal nodulizing process, in which the important anti-nodulizing elements Pb, Bi and Al are added respectively in order to research the influence of them on the nodulization of the graphites. The nodular graphites are extracted from the nodular cast iron by the electrolytic technique. The distribution of trace elements in nodular and deformed graphites are measured by Scanning Proton Microprobe. A large part of Pb, Bi and Al exists in matrix as impurities, a part of them intrudes into the nodular graphites. A new suggestion of Ti anti-nodulizing properties is proposed. The influence of Pb, Bi and Al on the nodulization is indirectly performed through Ti. Therefore, Ti is one of the most important anti-nodulizing elements

  15. Effects of striated laser tracks on thermal fatigue resistance of cast iron samples with biomimetic non-smooth surface

    International Nuclear Information System (INIS)

    In order to enhance the thermal fatigue resistance of cast iron materials, the samples with biomimetic non-smooth surface were processed by Neodymium:Yttrium Aluminum Garnet (Nd:YAG) laser. With self-controlled thermal fatigue test method, the thermal fatigue resistance of smooth and non-smooth samples was investigated. The effects of striated laser tracks on thermal fatigue resistance were also studied. The results indicated that biomimetic non-smooth surface was benefit for improving thermal fatigue resistance of cast iron sample. The striated non-smooth units formed by laser tracks which were vertical with thermal cracks had the best propagation resistance. The mechanisms behind these influences were discussed, and some schematic drawings were introduced to describe them.

  16. Effect of RE Modification and Heat Treatment on Impact Fatigue Property of a Wear Resistant White Cast Iron

    Institute of Scientific and Technical Information of China (English)

    常立民; 刘建华; 张瑞军; 王继东

    2004-01-01

    The morphology of carbides, as well as the generation and propagation of fatigue cracks in a wear resistant white cast iron after impact fatigue test were observed by means of optical microscope and SEM, and the relationship among the content of RE (rare earths) in the wear resistant white cast iron and the heating temperature as well as the length and propagation speed of the fatigue cracks were determined. Based on the obtained results, the effect of RE modification and heat treatment on the impact fatigue property was further studied. Experimental results show that addition of RE can defer the time required for the generation of fatigue cracks, reduce their propagation speed and increase the impact fatigue resistance. The aforesaid effect is more noticeable in case of combined RE modification with heat treatment, which can be attributed to the variation in morphology and the distribution of the eutectic carbide network.

  17. Low temperature impact toughness and fracture mechanism of cast QT400-18L ductile iron with different Ni additions

    OpenAIRE

    Zhang Xinning; Qu Yingdong; Yang Hongwang

    2013-01-01

    Different contents of Ni (0.3wt.% to 1.2wt.%) were added to the QT400-18L ductile iron to investigate the effect of Ni addition on the impact toughness of cast ductile irons at low temperatures. The impact toughnesses of the samples at room and low temperatures were tested. The microstructures and fractographs were observed. Results show that with the increase of Ni addition there is a general trend of refinement of the ferrite matrix while the nodule density shows no obvious change. When the...

  18. Using Cored Wires Injection 2PE-9 Method in the Production of Ferritic Si-Mo Ductile Iron Castings

    Directory of Open Access Journals (Sweden)

    E. Guzik

    2012-12-01

    Full Text Available The results of studies on the use of modern two cored wires injection method for production of ferritic nodular cast iron (ductile iron with use of unique implementation of drum ladle as a treatment / transport and casting ladle instead vertical treatment ladle was described. The injection of length of Ø 9mm wires, cored: in FeSi + Mg nodulariser mixture and inoculant master alloy is a treatment method which can be used to produce iron melted in coreless induction furnace. This paper describes the results and analysis of using this method for optimal production of ductile iron under specific industrial conditions. It means, that length of nodulariser wire plus treatment and pouring temperatures were optimized. In this case, was taken ductile iron with material designation: EN-GJS-SiMo40-6 Grade according EN 16124:2010 E. Microstructure of great number of trials was controlled on internally used sample which has been correlated with standardsample before. The paper presents typical ferritic metallic matrix and nodular graphite. Additionally, mechanical properties were checked in some experiments. Mean values of magnesium recovery and cost of this new method from optimized process parameters werecalculated as well.

  19. Damage Analysis of a Ferritic SiMo Ductile Cast Iron Submitted to Tension and Compression Loadings in Temperature

    OpenAIRE

    Isabel Hervas; Anthony Thuault; Eric Hug

    2015-01-01

    Tensile and compression tests were carried out on a ductile cast iron for temperatures up to 1073 K. The damage caused inside and around graphite nodules was evaluated as a function of the local equivalent plastic strain by using microstructural quantifications. The mechanical properties are strongly dependent on a temperature above 773 K. Concerning tensile behavior, an evolutional law issued from the Gurson model representing the void growth as a function of the deformation and temperature ...

  20. Modeling of damage in ductile cast iron – The effect of including plasticity in the graphite noduless

    DEFF Research Database (Denmark)

    Andriollo, Tito; Thorborg, Jesper; Tiedje, Niels Skat;

    2015-01-01

    In the present paper a micro-mechanical model for investigating the stress-strain relation of ductile cast iron subjected to simple loading conditions is presented. The model is based on a unit cell containing a single spherical graphite nodule embedded in a uniform ferritic matrix, under the...... stresses due to the cooling process during manufacturing are also considered. Numerical solutions are obtained using an in-house developed finite element code; proper comparison with literature in the field is given....

  1. Perspectives of molibdenum containing materials application for alloying of iron-carbon alloys during manufacturing of critical castings

    OpenAIRE

    A. G. Slutsky; A. S. Kalinichenko; R. E. Trubitsky; V. A. Sheinert

    2015-01-01

    Motor is one of most important part of automobile determine its economical effectiveness of usage. On the other hand, sleeves, pistons and rings are crucible parts as they determine the service life of a motor. These parts are producing in big scale – dozens of millions pieces. Increase of cylinder sleeves physical-mechanical properties results in prolongation of motor service life and improvement of motor’s characteristics. Nowadays low alloyed cast irons with perlite structure are used to m...

  2. Transmission electron microscope studies of the chromium cast iron modified at use of B4C addition

    Directory of Open Access Journals (Sweden)

    K. Labisz

    2010-10-01

    Full Text Available Results of studies of the high alloy chromium cast iron with boron addition in form of the B4C phase powder are presented in this paper.The main field of interest is the identification of phases based on the transmission electron microscope study, occurred in this alloy aftersolidification process. The structure mainly consists of the austenite matrix and M7C3 carbide identified as the Cr7C3 phase.

  3. Effects of MC-Type Carbide Forming and Graphitizing Elements on Thermal Fatigue Behavior of Indefinite Chilled Cast Iron Rolls

    Science.gov (United States)

    Ahiale, Godwin Kwame; Choi, Won-Doo; Suh, Yongchan; Lee, Young-Kook; Oh, Yong-Jun

    2015-11-01

    The thermal fatigue behavior of indefinite chilled cast iron rolls with various V+Nb contents and Si/Cr ratios was evaluated. Increasing the ratio of Si/Cr prolonged the life of the rolls by reducing brittle cementites. Higher V+Nb addition also increased the life through the formation of carbides that refined and toughened the martensite matrix and reduced the thermal expansion mismatch in the microstructure.

  4. Effect of partial remelting time on the initial carbide in semisolid structure of hypereutectic hih Cr cast iron

    OpenAIRE

    Huang, Zhifu; Jiandong XING; He, Wei

    2004-01-01

    In order to review the effect of partial remelting time on the morphology of initial carbides, semisolid ingots of hypereutectic high Cr17 cast iron were remelted at 1 270 ℃ for four different times, and the changing characteristics of shape factor an the equivalent diameter of initial carbides were analyzed quantitatively using a Leica image analyzer. The results indicate that firstly, the evolution process of the initial carbides' morphology undergoes melting, sheroidization and refining d...

  5. Effect of Slope Plate Variable and Reheating on the Semi-Solid Structure of Ductile Cast Iron

    Institute of Scientific and Technical Information of China (English)

    M. Nili-Ahmadabadi; F. Pahlevani; P. Babaghorbani

    2008-01-01

    Semi-solid metal casting and forming is a promising production method for a wide range of metal alloys. In spite of many applications for semi-solid processed light alloys, few works have reported on the semi-solid processing of iron and steel. In this research, an inclined plate was used to change the dendritic structure of iron to globular. The effects of the length and slope of the plate on the casting structure were examined. The results show that the process effectively changes the dendritic structure to globular. A sloped plate angle of 7.5° and length of 560 mm with a cooling rate of 67 K·s-1 gave the optimum graphite nodu-larity and solid particle globularity. The results also show that the sloped plate more easily prevents inocu-lant fading since the total time processing is rather short. In addition the semi-solid ductile cast iron prepared using the inclined plate method was reheated to examine the effect of reheating conditions on the micro-structure and coarsening kinetics of the alloy. The solid fractions at different reheating temperatures and holding times were used to find the optimum reheating temperature range.

  6. The effect of the gaseous-plasma jet treatment of the powder vanadium cast iron and chromium mixture on the composition, structure powder and the casting properties

    International Nuclear Information System (INIS)

    The peculiarities of interaction in the low-temperature plasma of two powders, essentially differing in the melt temperature, are considered. The particles of the vanadium cast iron and chromium were chosen for the studies. The powders of three compositions with fractions from 50 up to 100 μm were obtained after mixing, combined regrinding and sifting the fractions from 50 up to 100 μm. The powders were transmitted through the plasma in the argon-nitrogen medium and quenched in the water. The conclusion on the oxidation and decarbonization of the particles by melting in the gaseous-plasma jet and cooling in the water may be made by the results of chemical analysis of various powder fractions. It is established, that by combined transfer of the cast iron and chromium particles, differing in the composition and melting temperature, there occurs their redistribution by fractions due to interaction bulk density, spillage density and yield morphology and increase in their internal porosity. Sufficiently high properties of coatings are provided for on the account of the particles statistically uniform distribution in spite of their nonuniformity by composition, structure and properties

  7. Dissimilar joining of nickel aluminide intermetallic compound with spheroidal graphite cast iron by using combustion synthesis

    Energy Technology Data Exchange (ETDEWEB)

    Kimata, T.; Uenishi, K.; Kobayashi, K.F. [Dept. of Manufacture Science, Osaka Univ., Osaka (Japan); Ikenaga, A. [Dept. of Metallurgy and Material Science, Osaka Prefecture Univ., Osaka (Japan)

    2004-07-01

    Nickel aluminide based intermetallic compounds were combustion synthesized from a powder mixture of elemental Al, Ni, and Si and were simultaneously bonded with spheroidal graphite cast iron substrate (FCD). Addition of Si to the elemental mixture of Al and Ni was confirmed to be effective both to the densification of combustion synthesized intermetallic compounds and to the joining between compounds and FCD. When the composition of precursor was Ni-69at%Al-9at%Si (Al/Si is the ratio of the eutectic composition), Al{sub 3}Ni and Al{sub 6}Ni{sub 3}Si were mainly combustion synthesized. In the interface between compounds and FCD, reaction layers were formed to the thickness of 10 {mu}m and the constitutent phases were identified as Al{sub 7}Fe{sub 2}Si, FeAl{sub 3} respectively. In the four point bending test of the dissimilar joints prepared by heating at 973 K for 300 s, the brittle fracture did not occurred around the joint interface but mainly in the inside of nickel aluminide coating. The interface of reaction layers with 10 {mu}m were chemically well bonded. The sample with Ni-69at%Al-9at%Si coating exhibited highest bonding strength of about 56 MPa because of the smallest void ratio of the obtained compounds. (orig.)

  8. Prestressed cast iron pressure vessels as burst-proof pressure vessels for innovative nuclear applications

    International Nuclear Information System (INIS)

    The amendment to the German Atomic Energy Act from July 28, 1994 requires that events 'whose occurrence is practically excluded by the measures against damages', i.e. events of the category residual risk, must not necessitate far reaching protective measures outside the plant. For a conventional reactor pressure vessel, the residual risk consists in the very small probability of a catastrophic failure (formation of a large fracture opening, bursting of the vessel). With a prestressed cast iron vessel (PCIV), the formation of a large fracture opening or bursting of the vessel, respectively, is impossible due to its design properties. Against this background the possibility of the use of this type of pressure vessel for lightwater reactors has been studied in the frame of a 'Working Group for Innovative Nuclear Technology', founded by different research institutes and industrial companies. Furthermore, it has been studied whether the use of the PCIV support the realization of a corecatcher system. The results are presented in this report. Already many years earlier, Siempelkamp has performed industrial development and Forschungszentrum Juelich related experimental and theoretical safety research for the PCIV as an innovative, bust-proof pressure vessel concept. This development of the PCIV as well as its safety properties are also presented in a conclusive manner. (orig.)

  9. Performance Study of Cryogenically Treated HSS Drills in Drillilg Gray Cast Iron Using Orthogonal Array Technique

    Directory of Open Access Journals (Sweden)

    B.R. Ramji

    2010-08-01

    Full Text Available The objective of this research was to study the performance of cryogenically treated HSS drills for drilling gray cast iron. Drilling experiments were conducted with cutting speeds: 560, 710, 900, 1120 rpm, feeds: 0.05, 0.08, 0.12, 0.19 mm/rev and a constant drill diameter: 8 mm. The cryogenic treatment cycle consisted of cooling the test samples from room temperature to cryogenic temperature of -178.9ºC in 3 h, soaking at cryogenic temperature for 24 h and w arming to room temperature in about 5 h. The thrust force and torque were measured using drill tool dynamometer. The surface roughness (Ra, Rz, Rq and R t of the drilled specimens were measured using talysurf. The experimental lay-out was designed using Taguchi’s Orthogonal Array technique. Signal-to-Noise Ratio analysis was performed to identify the effect of the parameters on the response variables. The treated drills were found superior to the non-treated in all the test conditions in terms of lesser thrust force, torque and also superior surface roughness of the specimens. The tool wear was studied using SEM.

  10. Numerical Modelling of Mechanical Integrity of the Copper-Cast Iron Canister. A Literature Review

    International Nuclear Information System (INIS)

    This review article presents a summary of the research works on the numerical modelling of the mechanical integrity of the composite copper-cast iron canisters for the final disposal of Swedish nuclear wastes, conducted by SKB and SKI since 1992. The objective of the review is to evaluate the outstanding issues existing today about the basic design concepts and premises, fundamental issues on processes, properties and parameters considered for the functions and requirements of canisters under the conditions of a deep geological repository. The focus is placed on the adequacy of numerical modelling approaches adopted in regards to the overall mechanical integrity of the canisters, especially the initial state of canisters regarding defects and the consequences of their evolution under external and internal loading mechanisms adopted in the design premises. The emphasis is the stress-strain behaviour and failure/strength, with creep and plasticity involved. Corrosion, although one of the major concerns in the field of canister safety, was not included

  11. Thermal energy storage using Prestressed Cast Iron Vessels (PCIV). Final report

    Energy Technology Data Exchange (ETDEWEB)

    Gilli, P.V.; Beckmann, G.; Schilling, F.E.

    1977-06-01

    The wide-spread application of thermal energy and high-pressure air storage to electric power generation has so far been hampered by the lack of large high-pressure storage vessels of reasonable cost. Welded steel vessels are too expensive for this purpose. However, the Prestressed Cast Iron Vessel (PCIV), developed as a nuclear reactor pressure vessel by Siempelkamp Giesserei KG of Krefeld, FRG, has the potential of complying with these requirements. Applications of the PCIV include: high-pressure air storage for the quick start-up of open cycle gas turbines; pressurized high-temperature sensible heat storage by means of solids with a gaseous heat transfer medium for closed cycle gas turbines of future solar power stations; and pressurized hot water storage for nuclear, solar, or coal-fired steam power plants, employing either separate peaking turbines or overloadable main turbine sets. A reference PCIV of 8000 m/sup 3/, 275/sup 0/C, with hot going walls and cold going tendons was developed, designed, and stress-analysed. A parametric study showed that pressures between 4 and 8 MPa and L/D ratios larger than 4 should be optimal. Cost of the reference vessel is about $10,000,000 or 33 to 50 $/kWh electric energy stored. Cost of peak power will be from 30 to 100 mills/kWh, depending on many parameters.

  12. A mathematical model for electrochemical chloride removal from marine cast iron artifacts

    Institute of Scientific and Technical Information of China (English)

    Weizhen OUYANG; Xia CAO; Ning WANG

    2009-01-01

    The aim of this article was to theoretically study diffusion and migration of chlo-ride ions during electrochemical chloride removal. The proposed model would enable optimization of its application by predicting the optimal treatment time and current combination. A mathematical model for simulating the transport behavior of chloride ions was developed by consideration of diffusion and migration of chloride ions when a constant DC current density was applied through the marine cast iron artifacts. The corresponding tests were conducted to validate the mathematical model. This model predicted the data of the extraction ratio of the chloride ion that correlated satisfac-torily with the experimental values. An important issue in electrochemical chloride removal was to understand how chloride ions moved, taking account of diffusion and migration of chloride ions and the release of binding chloride ions. The effects of the treatment time, externally applied current density, chloride diffusion coefficient, and rate constant of release of binding chloride ion on chloride removal are studied. The specific quantitative details applied to one-dimensional model were discussed here. This article has proposed a mathematical model for the first time, which was showed to be a useful tool that can reveal the ionic transport mechanism and optimize the application during electrochemical chloride removal.

  13. Application of Averaged Voronoi Polyhedron in the Modelling of Crystallisation of Eutectic Nodular Graphite Cast Iron

    Directory of Open Access Journals (Sweden)

    A.A. Burbelko

    2013-01-01

    Full Text Available The study presents a mathematical model of the crystallisation of nodular graphite cast iron. The proposed model is based on micro- andmacromodels, in which heat flow is analysed at the macro level, while micro level is used for modelling of the diffusion of elements. The use of elementary diffusion field in the shape of an averaged Voronoi polyhedron [AVP] was proposed. To determine the geometry of the averaged Voronoi polyhedron, Kolmogorov statistical theory of crystallisation was applied. The principles of a differential mathematical formulation of this problem were discussed. Application of AVP geometry allows taking into account the reduced volume fraction of the peripheral areas of equiaxial grains by random contacts between adjacent grains.As a result of the simulation, the cooling curves were plotted, and the movement of "graphite-austenite" and "austenite-liquid” phaseboundaries was examined. Data on the microsegregation of carbon in the cross-section of an austenite layer in eutectic grains wereobtained. Calculations were performed for different particle densities and different wall thicknesses. The calculation results were compared with experimental data.

  14. Influence of Mg on Solidification of Hypereutectic Cast Iron: X-ray Radiography Study

    Science.gov (United States)

    Yamane, K.; Yasuda, Hideyuki; Sugiyama, A.; Nagira, T.; Yoshiya, M.; Morishita, K.; Uesugi, K.; Takeuchi, A.; Suzuki, Y.

    2015-11-01

    Radiography using a synchrotron radiation X-ray source was performed to examine solidification and melting behaviors in hypereutectic cast iron specimens containing 0.002 and 0.05mass pctMg. The solidification sequence in the alloy containing 0.002mass pctMg was (1) nucleation and growth of graphite particles of which transformed to a flake-like shape, (2) growth of γ-Fe dendrites, (3) nucleation of graphite particles ahead of the interface just prior to the eutectic solidification, and (4) the eutectic solidification. In contrast, (1) and (2) occurred nearly at the same time in the specimen containing 0.05 mass pct Mg. The addition of 0.05mass pctMg significantly reduced the temperature range in which the graphite particles grew as the primary phase. Image-based analysis of melting behavior showed that even 0.05 mass pct addition was sufficient to modify the phase equilibrium of the liquid, γ-Fe, and graphite phases. Thus, the observed influence of Mg on the solidification sequence was attributed to the modification of the phase equilibrium. The influence was consistently explained by considering the shift of the eutectic composition to the carbon side in the pseudo-ternary system. It was also suggested that supersaturation of carbon in the melt increased as the temperature decreased even though the primary graphite particles existed. The supersaturation may cause the nucleation of the graphite particles just before the eutectic solidification.

  15. Study on fragmentation and dissolution behavior of carbide in a hot-rolled hypereutectic high chromium cast iron

    International Nuclear Information System (INIS)

    Highlights: • The method to prepare Carbon steel/High chromium iron is totally new. • High chromium iron can achieve small plastic deformation during hot rolling process. • Carbides in high chromium irons are crushed, refined obviously and becoming isolated, which is benefit to improve the impact toughness. • The carbide fragmentation and dissolution behavior of the hot-rolled HCCI were analyzed. - Abstract: A sandwich-structured composite containing a hypereutectic high chromium cast iron (HCCI) and low carbon steel (LCS) claddings was newly fabricated by centrifugal casting, then the blank was hot-rolled into composite plate. The carbide fragmentation and dissolution behavior of the hot-rolled HCCI were analyzed. During hot rolling, significant refinement of carbides was discovered in hot-rolled HCCI specimens. The carbides were broken and partly dissolved into the austenite matrix. The results show that carbides are firstly dissolved under the action of stress. There are grooves appeared at the boundaries of the carbides. The grooves reduce the cross section of the carbide. When the cross section of the carbide reaches to the required minimum critical cross section, the carbide breaks through the tensile force. After break, carbides continue to dissolve since more interfaces between the matrix and carbides are generated. The secondary carbides precipitated due to the dissolution are index as fcc and stacking faults parallel to the {1 1 1} are observed

  16. Study on fragmentation and dissolution behavior of carbide in a hot-rolled hypereutectic high chromium cast iron

    Energy Technology Data Exchange (ETDEWEB)

    Liu, Fei; Jiang, Yehua, E-mail: jiangyehua@kmust.edu.cn; Xiao, Han; Tan, Jun

    2015-01-05

    Highlights: • The method to prepare Carbon steel/High chromium iron is totally new. • High chromium iron can achieve small plastic deformation during hot rolling process. • Carbides in high chromium irons are crushed, refined obviously and becoming isolated, which is benefit to improve the impact toughness. • The carbide fragmentation and dissolution behavior of the hot-rolled HCCI were analyzed. - Abstract: A sandwich-structured composite containing a hypereutectic high chromium cast iron (HCCI) and low carbon steel (LCS) claddings was newly fabricated by centrifugal casting, then the blank was hot-rolled into composite plate. The carbide fragmentation and dissolution behavior of the hot-rolled HCCI were analyzed. During hot rolling, significant refinement of carbides was discovered in hot-rolled HCCI specimens. The carbides were broken and partly dissolved into the austenite matrix. The results show that carbides are firstly dissolved under the action of stress. There are grooves appeared at the boundaries of the carbides. The grooves reduce the cross section of the carbide. When the cross section of the carbide reaches to the required minimum critical cross section, the carbide breaks through the tensile force. After break, carbides continue to dissolve since more interfaces between the matrix and carbides are generated. The secondary carbides precipitated due to the dissolution are index as fcc and stacking faults parallel to the {1 1 1} are observed.

  17. Effect of rare earth element on microstructure formation and mechanical properties of thin wall ductile iron castings

    International Nuclear Information System (INIS)

    Ductile iron castings with 2, 3, 4, 6, 8, and 25 mm thickness and various amount of rare earth elements (RE) (from 0 to 0.04%), were cast in sand molds to identify the effects of sample thickness and the content of RE% on microstructural formation and selected mechanical properties. The effects of RE content and sample thickness on microstructural formation, including on graphite nodule count, graphite nodule shape, spherodization, and ferrite amount, were observed. The yield strength of the samples with RE within the range investigated were lower than those of the specimens without RE. The elongation was improved with the addition of RE up to 0.03% in ductile iron castings. The additions of 0.02% RE caused a smaller graphite nodule size and a higher number of graphite nodules than those in the specimen without RE at all levels of RE addition; the nodule count decreased with increase in section size. The chill zones were observed in the 2 mm thick samples, but were absent in the samples from castings which were thicker than 2 mm, irrespective of the addition of RE. The nodularity of graphite nodules improved due to the addition of 0.02-0.04% RE. The specimens with RE content up to 0.03% had a lower tensile strength and hardness, higher elongation than that of the specimens without RE. The ferrite content in all castings increased with additions of 0.02% RE. The tensile strengths of the 2 and 3 mm thick samples were also estimated using the relationship between strength and hardness, obtained from the data on the tensile strength and hardness of the 25 mm thick samples

  18. Development of ELID mirror surface grinding by cast iron bond grinding wheel. Ohkochi memorial technology prize; Chutetsu bond toishi ni yoru denkai inpurosesu doresshingu (ELID) kyomen kensakuho no kaihatsu. Okochi kinen gijutsusho jusho ni yosete

    Energy Technology Data Exchange (ETDEWEB)

    Omori, H.; Takahashi, I. [Institute of Physical and Chemical Research, Tokyo (Japan); Nakagawa, T. [The University of Tokyo, Tokyo (Japan). Institute of Industrial Science; Hagiuda, Y.; Karikome, K. [Tokyo Metropolitan College of Aeronautical Engineering, Tokyo (Japan)

    1997-08-01

    Development was accomplished on the electrolytic in-process dressing (ELID) mirror surface grinding process using a cast iron bonded grinding wheel. This paper describes the history of the development, which may be summarized as follows: a study was begun on powder forging of cutting chips in 1970; a research was started on powder forging of decarburized cast iron powder; developments were made on powder metallurgy of cast irons and cast iron bonded lapping tools in 1980, and cast iron bonded diamond grinding wheels were put on the market; a high-efficiency grinding process using MC and cast iron fiber-bonded grinding wheels were developed in 1985 and the grinding wheels made therefrom were put on the market; and a study was begun on the ELID grinding in 1987, and marketing was started on power supply, grinding liquid and tools for the ELID grinding process in 1990. Discussions on converting raw materials for the powder forging into cutting chips have triggered developing the cast iron bonded grinding wheel. The cast iron bonded diamond grinding wheel improves dressability and sharpness of conventional grinding wheels. The grinding wheel is fabricated by mixing carbonyl iron powder, diamond grinding grains and cast iron powder, pressing the mixture in a die, sintering it at 1140 degC, and assembling and dressing the sinter. The grinding stone can grind high-tech materials. 4 figs.

  19. Effect of Destabilizing Heat Treatment on Solid-State Phase Transformation in High-Chromium Cast Irons

    Science.gov (United States)

    Efremenko, Vasily; Shimizu, Kazumichi; Chabak, Yuliia

    2013-12-01

    This work describes the influence of secondary carbide precipitation at destabilizing heat treatment on kinetics of austenite phase transformation at a subcritical range of temperatures in high-Cr cast irons, alloyed with 4 to 6 wt pct of Mn or by complex Mn-Ni-Mo (Mn-Cu-Mo). The samples were soaked at 1073 K to 1373 K (800 °C to 1100 °C) (destabilization) or at 573 K to 973 K (300 °C to 700 °C) (subcritical treatment); the combination of destabilization and subcritical treatment was also used. The investigation was carried out with application of optical and electron microscopy and bulk hardness measurement. Time-temperature-transformation (TTT) curves of secondary carbide precipitation and pearlite transformation for as-cast austenite and destabilized austenite were built in this work. It was determined that the secondary carbide precipitation significantly inhibited the pearlite transformation rate at 823 K to 973 K (550 °C to 700 °C). The inhibition effect is more evident in cast irons alloyed with complex Mn-Ni-Mo or Mn-Cu-Mo. The possible reasons for transformation decelerating could be austenite chemical composition change (enriching by Ni, Si, and Cu, and depleting by Cr) and stresses induced by secondary carbide precipitation.

  20. Effect of Ti, Nb, Cr and B on Structure and Mechanical Properties of High Aluminium Cast Iron

    Directory of Open Access Journals (Sweden)

    D. Kopyciński

    2013-01-01

    Full Text Available In this work, a method was investigated to eliminate the presence of undesirable Al4C3 phases in a high-aluminium alloys, and thusimprove the production process. The melting conditions employed in this work enabled the formation of a Fe-Al-C liquid solution.Moreover, titanium additions into the liquid allowed the precipitation of TiC. According to this reaction, the extent of carbon removal from the melt is strongly influenced by the amount of Ti additions. Hence, proper titanium levels can result in total removal of carbon from the liquid. Notice from this figure that Ti additions above 4.5%, totally eliminate the undesirable Al4C3 precipitates. Making Cr, Ti, B additions reduces size of FeAl alloys grains. In addition, this work indicates that the high-aluminium cast iron posses high oxidation resistance, exceeding that of high-chromium cast iron and chromium cast steels. Finally, the alloy ductility can be enhanced by additions of dopants such as B and Cr. Hence, additions of 0.03% B and 0.03%B-5% Cr combined with a heat treatment were implemented. As a result, the alloy ductility was significantly improved, where the strain of up to 5.3%, (B alone or 15% (B-Cr were obtained.

  1. The efect of cooling rate on the properties of alloyed cast-iron sizing roll

    Directory of Open Access Journals (Sweden)

    P. Jelić

    2010-01-01

    Full Text Available Directional heat transfer was investigated by temperature measurements in the casting and in the mould using thermocouples. Measurements were performed in operating conditions during pouring, solidification, and cooling of the casting. Total measurement time was 35,5 hours. After cutting, specimens were extracted for metallographic and hardness testing. Test results provided confirmation of directional heat transfer (directional cooling that would ensure acquirement of a desired casting structure and mechanical properties.

  2. Numerical modelling of solidification of thin walled hypereutectic ductile cast iron

    DEFF Research Database (Denmark)

    Pedersen, Karl Martin; Hattel, Jesper; Tiedje, Niels

    2006-01-01

    the presence of austenite dendrites even in hypereutectic castings. In thin-walled castings the presence of austenite dendrites is even more pronounced, which increases the risk of shrinkage porosities. This off-eutectic austenite is therefore an important part that should be taken into account during...

  3. Corrosion resistance of cast irons and titanium alloys as reference engineered metal barriers for use in basalt geologic storage: a literature assessment

    Energy Technology Data Exchange (ETDEWEB)

    Charlot, L.A.; Westerman, R.E.

    1981-07-01

    A survey and assessment of the literature on the corrosion resistance of cast irons and low-alloy titanium are presented. Selected engineering properties of cast iron and titanium are briefly described; however, the corrosion resistance of cast iron and titanium in aqueous solutions or in soils and their use in a basalt repository are emphasized. In evaluating the potential use of cast iron and titanium as structural barrier materials for long-lived nuclear waste packages, it is assumed that titanium has the general corrosion resistance to be used in relatively thin cross sections whereas the cost and availability of cast iron allows its use even in very thick cross sections. Based on this assumption, the survey showed that: The uniform corrosion of low-alloy titanium in a basalt environment is expected to be extremely low. A linear extrapolation of general corrosion rates with an added corrosion allowance suggests that a 3.2- to 6.4-mm-thick wall may have a life of 1000 yr. Pitting and crevice corrosion are not likely corrosion modes in basalt ground waters. It is also unlikely that stress corrosion cracking (SCC) will occur in the commercially pure (CP) titanium alloy or in palladiumor molybdenum-alloyed titanium materials. Low-alloy cast irons may be used as barrier metals if the environment surrounding the metal keeps the alloy in the passive range. The solubility of the corrosion product and the semipermeable nature of the oxide film allow significant uniform corrosion over long time periods. A linear extrapolation of high-temperature corrosion rates on carbon steels and corrosion rates of cast irons in soils gives an estimated metal penetration of 51 to 64 mm after 1000 yr. A corrosion allowance of 3 to 5 times that suggests that an acceptable cast iron wall may be from 178 to 305 mm thick. Although they cannot be fully assessed, pitting and crevice corrosion should not affect cast iron due to the ground-water chemistry of basalt.

  4. Corrosion resistance of cast irons and titanium alloys as reference engineered metal barriers for use in basalt geologic storage: a literature assessment

    International Nuclear Information System (INIS)

    A survey and assessment of the literature on the corrosion resistance of cast irons and low-alloy titanium are presented. Selected engineering properties of cast iron and titanium are briefly described; however, the corrosion resistance of cast iron and titanium in aqueous solutions or in soils and their use in a basalt repository are emphasized. In evaluating the potential use of cast iron and titanium as structural barrier materials for long-lived nuclear waste packages, it is assumed that titanium has the general corrosion resistance to be used in relatively thin cross sections whereas the cost and availability of cast iron allows its use even in very thick cross sections. Based on this assumption, the survey showed that: The uniform corrosion of low-alloy titanium in a basalt environment is expected to be extremely low. A linear extrapolation of general corrosion rates with an added corrosion allowance suggests that a 3.2- to 6.4-mm-thick wall may have a life of 1000 yr. Pitting and crevice corrosion are not likely corrosion modes in basalt ground waters. It is also unlikely that stress corrosion cracking (SCC) will occur in the commercially pure (CP) titanium alloy or in palladiumor molybdenum-alloyed titanium materials. Low-alloy cast irons may be used as barrier metals if the environment surrounding the metal keeps the alloy in the passive range. The solubility of the corrosion product and the semipermeable nature of the oxide film allow significant uniform corrosion over long time periods. A linear extrapolation of high-temperature corrosion rates on carbon steels and corrosion rates of cast irons in soils gives an estimated metal penetration of 51 to 64 mm after 1000 yr. A corrosion allowance of 3 to 5 times that suggests that an acceptable cast iron wall may be from 178 to 305 mm thick. Although they cannot be fully assessed, pitting and crevice corrosion should not affect cast iron due to the ground-water chemistry of basalt

  5. Microstructure and Wear Behavior of TiC Coating Deposited on Spheroidized Graphite Cast Iron Using Laser Surfacing

    OpenAIRE

    E. R. I. Mahmoud; H. F. El-Labban

    2014-01-01

    Spheroidal graphite cast iron was laser cladded with TiC powder using a YAG fiber laser at powers of 700, 1000, 1500 and 2000 W. The powder was preplaced on the surface of the specimens with 0.5 mm thickness. Sound cladding and fusion zones were observed at 700, 1000 and 1500 W powers. However, at 2000 W, cracking was observed in the fusion zone.  At 700 W, a build-up zone consisted of fine TiC dendrites inside a matrix composed of martensite, cementite (Fe3C), and some blocks of retaine...

  6. The Effect of Homogenization Heat Treatment on Thermal Expansion Coefficient and Dimensional Stability of Low Thermal Expansion Cast Irons

    Science.gov (United States)

    Chen, Li-Hao; Liu, Zong-Pei; Pan, Yung-Ning

    2016-08-01

    In this paper, the effect of homogenization heat treatment on α value [coefficient of thermal expansion (10-6 K-1)] of low thermal expansion cast irons was studied. In addition, constrained thermal cyclic tests were conducted to evaluate the dimensional stability of the low thermal expansion cast irons with various heat treatment conditions. The results indicate that when the alloys were homogenized at a relatively low temperature, e.g., 1023 K (750 °C), the elimination of Ni segregation was not very effective, but the C concentration in the matrix was moderately reduced. On the other hand, if the alloys were homogenized at a relatively high temperature, e.g., 1473 K (1200 °C), opposite results were obtained. Consequently, not much improvement (reduction) in α value was achieved in both cases. Therefore, a compound homogenization heat treatment procedure was designed, namely 1473 K (1200 °C)/4 hours/FC/1023 K (750 °C)/2 hours/WQ, in which a relatively high homogenization temperature of 1473 K (1200 °C) can effectively eliminate the Ni segregation, and a subsequent holding stage at 1023.15 K (750 °C) can reduce the C content in the matrix. As a result, very low α values of around (1 to 2) × 10-6 K-1 were obtained. Regarding the constrained thermal cyclic testing in 303 K to 473 K (30 °C to 200 °C), the results indicate that regardless of heat treatment condition, low thermal expansion cast irons exhibit exceedingly higher dimensional stability than either the regular ductile cast iron or the 304 stainless steel. Furthermore, positive correlation exists between the α 303.15 K to 473.15 K value and the amount of shape change after the thermal cyclic testing. Among the alloys investigated, Heat I-T3B (1473 K (1200 °C)/4 hours/FC/1023 K (750 °C)/2 hours/WQ) exhibits the lowest α 303 K to 473 K value (1.72 × 10-6 K-1), and hence has the least shape change (7.41 μm) or the best dimensional stability.

  7. The Effect of Homogenization Heat Treatment on Thermal Expansion Coefficient and Dimensional Stability of Low Thermal Expansion Cast Irons

    Science.gov (United States)

    Chen, Li-Hao; Liu, Zong-Pei; Pan, Yung-Ning

    2016-05-01

    In this paper, the effect of homogenization heat treatment on α value [coefficient of thermal expansion (10-6 K-1)] of low thermal expansion cast irons was studied. In addition, constrained thermal cyclic tests were conducted to evaluate the dimensional stability of the low thermal expansion cast irons with various heat treatment conditions. The results indicate that when the alloys were homogenized at a relatively low temperature, e.g., 1023 K (750 °C), the elimination of Ni segregation was not very effective, but the C concentration in the matrix was moderately reduced. On the other hand, if the alloys were homogenized at a relatively high temperature, e.g., 1473 K (1200 °C), opposite results were obtained. Consequently, not much improvement (reduction) in α value was achieved in both cases. Therefore, a compound homogenization heat treatment procedure was designed, namely 1473 K (1200 °C)/4 hours/FC/1023 K (750 °C)/2 hours/WQ, in which a relatively high homogenization temperature of 1473 K (1200 °C) can effectively eliminate the Ni segregation, and a subsequent holding stage at 1023.15 K (750 °C) can reduce the C content in the matrix. As a result, very low α values of around (1 to 2) × 10-6 K-1 were obtained. Regarding the constrained thermal cyclic testing in 303 K to 473 K (30 °C to 200 °C), the results indicate that regardless of heat treatment condition, low thermal expansion cast irons exhibit exceedingly higher dimensional stability than either the regular ductile cast iron or the 304 stainless steel. Furthermore, positive correlation exists between the α 303.15 K to 473.15 K value and the amount of shape change after the thermal cyclic testing. Among the alloys investigated, Heat I-T3B (1473 K (1200 °C)/4 hours/FC/1023 K (750 °C)/2 hours/WQ) exhibits the lowest α 303 K to 473 K value (1.72 × 10-6 K-1), and hence has the least shape change (7.41 μm) or the best dimensional stability.

  8. A probabilistic model for a gas explosion due to leakages in the grey cast iron gas mains

    International Nuclear Information System (INIS)

    In this paper we propose a model for the probability of an explosion caused by a leakage form grey cast iron pipes in the city of Amsterdam as a function of pipeline and environmental characteristics. The parameters in the model are quantified, with uncertainty, using historical data and structured expert judgment, by use of the Classical Model. Eleven experts from Dutch distribution system operators (DSO) and Kiwa Gas Technology participated in the research. The model has to provide the overall probability of an explosion per year and a prioritization of pipes in terms of their potential contribution to the probability of explosion, which can help DSO's to prioritize their replacements

  9. Preliminary science report on the directional solidification of hypereutectic cast iron during KC-135 low-G maneuvers

    Science.gov (United States)

    Curreri, P. A.; Stefanescu, D. M.; Hendrix, J. C.

    1983-01-01

    An ADSS-P directional solidification furnace was reconfigured for operation on the KC-135 low-g aircraft. The system offers many advantages over quench ingot methods for study of the effects of sedimentation and convection on alloy formation. The directional sodification furnace system was first flown during the September 1982 series of flights. The microstructure of the hypereutectic cast iron sample solidified on one of these flights suggests a low-g effect on graphite morphology. Further experiments are needed to ascertain that this effect is due to low-gravity and to deduce which of the possible mechanisms is responsible for it.

  10. Manufacture of centrifugal Castings

    OpenAIRE

    Minář, Martin

    2015-01-01

    The main goal of this bachelor thesis is to collect basic information related to the production of castings by centrifugal casting. It is focused on horizontal and vertical centrigugal casting, casting of various metals and their alloys, such as zinc, aluminum, iron, steel and silumin. This technology is compared with other casting methods in terms of specific characteristics, amount of usage, production economics, advantages, disadvantages, the resulting quality of castings and other factors.

  11. High Temperature Oxidation Behavior of Laser Surface Modification Layer with Thermal Sprayed Coating on Ductile Cast Iron

    International Nuclear Information System (INIS)

    The ductile cast iron substrate was coated with Al and Al-Ni powder by low pressure spraying and it was irradiated with a CO2 laser. The isothermal oxidation behavior on its surface modification layer was investigated at high temperature (1023, 1123K) in air during 24 hours. The oxidation kinetics of DA and DAN laser alloyed layer were shown to follow a parabolic rate law over the DA50 specimen was approximately decreased from one-third to one-sixth than DAN's. The DA50 alloyed layer was difficult to grow its oxide scale, since dense aluminum oxide was produced on the interface of alloyed layer. High temperature corrosion resistance of the DAN alloyed layer was greatly decreased as compared with DA50's. Therefore, it is considered that external iron oxide layer contains porosity or crack as well as Ni-rich internal oxide layer

  12. INFLUENCE OF THE METAL MATRIX STRUCTURE OF HIGH-DUTY CAST IRON ON COERCIVELY SENSITIVE MAGNETIC PARAMETER AND SPEED OF SOUND

    OpenAIRE

    S. G. Sandomirsky; V. L. Tsukerman

    2013-01-01

    The analysis of influence of changes in the structure of the metal base of high-duty cast ironcompact castings with a constant form of graphite inclusions on the coercive sensitive magnetic parameters and the speed of sound is held. The efficiency of joint use of the results of magnetic and ultrasonic measurements to control the shape of inclusions in the iron and pearlite content in its metallic matrix is shown.

  13. INFLUENCE OF THE METAL MATRIX STRUCTURE OF HIGH-DUTY CAST IRON ON COERCIVELY SENSITIVE MAGNETIC PARAMETER AND SPEED OF SOUND

    Directory of Open Access Journals (Sweden)

    S. G. Sandomirsky

    2013-01-01

    Full Text Available The analysis of influence of changes in the structure of the metal base of high-duty cast ironcompact castings with a constant form of graphite inclusions on the coercive sensitive magnetic parameters and the speed of sound is held. The efficiency of joint use of the results of magnetic and ultrasonic measurements to control the shape of inclusions in the iron and pearlite content in its metallic matrix is shown.

  14. Simulation of Heat Flow in Computational Method and Its Verification on the Structure and Property of Gray Cast Iron

    Directory of Open Access Journals (Sweden)

    S. K. Shaha

    2010-01-01

    Full Text Available Problem statement: The solidification of materials depends on the cooling rate of the materials which is governed by heat flow in the mould and alloy composition. Solidification rate also affects the structure and properties of the materials. Approach: In the present study, the heat flow of cold set resin bonded sand mould was simulated using JL Analyzer FEM analysis software. To verify the model, the gray cast iron was melted at 1350°C temperature and poured into a resin bonded sand mould at 1300°C. Results: It showed that most of the heat-reserve at the junction of the mould which was nearer to the source of liquid metal and the lowest heat-reserve at the end of the mould. So, the solidification rate was very high at the end of the mould wall whereas it was comparatively low near the sprue of the mould. Conclusion: Finally, depending on the heat-flow through the mould, the solidification rate changed the microstructure from chill, mottled and gray cast iron and hardness changed from 95.1 HRB-78.78 HRB.

  15. Technologies of doping of cast iron through the slag phase with using of the spent nickel- and copper-containing catalysts

    OpenAIRE

    I. B. Provorova; O. S. Komarov; K. E. Baranowski; V. I. Volosatikov

    2015-01-01

    We have defined the regularities of the doping of cast iron through the slag phase of nickel and copper due to the waste catalysts using a carbonaceous reducing agent. We have justified the need to use the cast iron chips as a seed in the composition of the slag mixture. We have defined the dependence of the degree of extraction of nickel or copper from spent catalyst on the amount of the catalyst, on the basicity of the slag mixture, on the temperature and time of melting.

  16. TECHNOLOGIES OF DOPING OF CAST IRON THROUGH THE SLAG PHASE WITH USING OF THE SPENT NICKEL- AND COPPER-CONTAINING CATALYSTS

    Directory of Open Access Journals (Sweden)

    I. B. Provorova

    2015-11-01

    Full Text Available We have defined the regularities of the doping of cast iron through the slag phase of nickel and copper due to the waste catalysts using a carbonaceous reducing agent. We have justified the need to use the cast iron chips as a seed in the composition of the slag mixture. We have defined the dependence of the degree of extraction of nickel or copper from spent catalyst on the amount of the catalyst, on the basicity of the slag mixture, on the temperature and time of melting.

  17. Study on plasma-spraying Ni-Al-WC alloy layer on the surface of chrome cast iron and alloy layer's micro-structure and properties

    International Nuclear Information System (INIS)

    Plasma-spraying Ni-Al-WC alloy layer on the surface of chrome cast iron and alloy layer's micro-structure and properties are studied. The analysis items include chemical composition, phase structure, average microhardness, wear resistance and corrosion resistance. The experimental results indicate that metallurgical combination has been achieved completely between the spraying layer and the surface of chrome cast iron, and that the chemical composition and micro-structure in the surface layer of the sample have been changed basically, and that the microhardness, the wear resistance, the corrosion resistance in the surface layer are increased by a large margin

  18. The role of iron in the formation of porosity in Al-Si-Cu-based casting alloys. Part 1: Initial experimental observations

    Energy Technology Data Exchange (ETDEWEB)

    Taylor, J.A.; Schaffer, G.B.; StJohn, D.H. [Univ. of Queensland, Brisbane, Queensland (Australia)

    1999-06-01

    Outbreaks of interconnected porosity in industrial Al-Si-based alloy castings have, on occasion, been attributed to variations in metal chemistry rather than to changes in process parameters. This work identifies the role that iron plays in porosity formation and reports a threefold effect in an Al-5 pct Si-1 pct Cu-0.5 pct Mg alloy. In addition to a detailed analysis of casting porosity profiles, metallographic and thermal studies also point to inadequacies in the existing theories regarding the role of iron and suggest that a new theory is required to understand the observed behavior.

  19. Corrosion behaviour of some cast stainless steels and high alloy white irons in scrubber solutions of flue gas desulfurization plants

    International Nuclear Information System (INIS)

    Weight loss and electrochemical measurements have been used to determine the ranges of applicability of cast austenitic stainless steel Werkstoff No. 1.4408, of two special cast ferritic-austenitic stainless steels NORIDUR 9.4460 and NORICLOR NC 246 and of two high alloy Cr and CrMo white irons in scrubber solutions of Flue Gas Desulfurization (FGD) plants. Whereas the Werkstoff No. 1.4408 cannot be used due to its insufficient resistance to general and localized corrosion, NORIDUR 9.4460 can be used in scrubber solutions with pH > 2.5 and chloride concentrations up to 80 g/l, NORICLOR NC 246 with 5% Mo even in liquids with pH > 1.5 and chlorides up to 100 g/l. At lower pH-values both duplex stainless steels show active corrosion of either the austenite or the ferrite depending on the contents of hydrochloric acid in the solution. At higher chloride concentrations pitting occurs on the passive materials. The CrMo white iron NORILOY NL 252 with 25% Cr and 2% Mo can be used in scrubber liquids with pH > 3.5. As the ferritic matrix is cathodically protected by the precipitated carbides, there is no sensitivity of this alloy to chlorides. In liquids with pH < 3.5 there is selective corrosion of the ferritic matrix. For practical application of all these cast alloys the limits for purely corrosive attack have to be modified to assure resistance to a superposition of corrosion, erosion/abrasion and cavitation on parts exposed to real flow conditions in FGD scrubbers. (orig.)

  20. SORTING CAPABILITIES OF CASTINGS FROM NODULAR AND GRAY IRON BY THE STRUCTURE BY THE RESULT OF THE MEASUREMENT OF THE MAGNETIC PARAMETERS AND THE SPEED OF SOUND

    Directory of Open Access Journals (Sweden)

    S. G. Sandomirskiy

    2013-01-01

    Full Text Available The results of the analysis of the influence of changes in the structure of the metal substrate and form of graphite inclusions in cast iron on the magnetic coercive sensitive parameter and the speed of sound are given. The efficiency of shared use of the results of magnetic and ultrasonic measurements to control the shape of inclusions in ductile iron and pearlite content in its metal matrix is shown.

  1. SORTING CAPABILITIES OF CASTINGS FROM NODULAR AND GRAY IRON BY THE STRUCTURE BY THE RESULT OF THE MEASUREMENT OF THE MAGNETIC PARAMETERS AND THE SPEED OF SOUND

    OpenAIRE

    S. G. Sandomirskiy; V. L. Zuckerman

    2013-01-01

    The results of the analysis of the influence of changes in the structure of the metal substrate and form of graphite inclusions in cast iron on the magnetic coercive sensitive parameter and the speed of sound are given. The efficiency of shared use of the results of magnetic and ultrasonic measurements to control the shape of inclusions in ductile iron and pearlite content in its metal matrix is shown.

  2. Experimental validation of error in temperature measurements in thin walled ductile iron castings

    DEFF Research Database (Denmark)

    Pedersen, Karl Martin; Tiedje, Niels Skat

    2007-01-01

    thicknesses between 2 and 4.3 mm. The thermocouples were accurately placed at the same distance from the surface of the casting for different plate thicknesses. It is shown that when measuring the temperature in plates with thickness between 2 and 4.3 mm the measured temperature will be parallel shifted to a...... level about 20C lower than the actual temperature in the casting. Factors affecting the measurement error (oxide layer on the thermocouple wire, penetration into the ceramic tube and variation in placement of thermocouple) are discussed. Finally, it is shown how useful cooling curve may be obtained in...

  3. Characterization of Coated Sand Cores from Two Different Binder Systems for Grey Iron Castings

    DEFF Research Database (Denmark)

    Nwaogu, Ugochukwu Chibuzoh; Tiedje, Niels Skat; Poulsen, Thomas; Bischoff, Claus

    veining and metal penetration defects. The use of refractory coatings on cores is fundamental to obtaining acceptable casting surface quality and is used on resin bonded cores in production foundries. In this study new sol gel-coated sand cores made from coldbox and furan binder systems were investigated......Expansion defects on the surface of the castings include sand burn-in, metal penetration and/or veining, finning or scab. Veining or finning and metal penetration are of interest. These defects are associated with silica sand and result from the penetration of liquid metal into cracks formed during...

  4. Temperature measurement during solidification of thin wall ductile cast iron. Part 2: Numerical simulations

    DEFF Research Database (Denmark)

    Pedersen, Karl Martin; Tiedje, Niels Skat

    2008-01-01

    of factors influencing temperature measurement in thin walled castings was carried out. The calculations are based on and compared with experiments presented in part 1 of this paper. The analysis shows that the presence of the TC has only a minor influence on the microstructure of the casting. The...... influence is restricted to a volume within 2mm from the TC. Measured cooling curves will have the right shape. In a 2 mm plate the measured temperature was 17 °C below the true temperature in the melt. However, the cooling curve provides important information about nucleation and growth during...

  5. Corrosion behaviour of water waste on the gray cast iron sanitary pipelines

    International Nuclear Information System (INIS)

    The works of Plato (427-347 B.C.) contained the written description of corrosion. Plato defined rust as the earthy component separating out of the metal. (Georgius Agrico La) held to the same opinion some 2000 years later in his great mineralogical work De Natura Fossilium Iron rust (rat. Ferrug or Rubigo) is, so to speak, assertion of metallic iron. Iron can be protected against this defect by various wrapping, such as red lead, white lead, gypsum, bitumen or tar. Gaius Secundus Pliny also mentioned bitumen, pitch, white lead, and gypsum as protecting iron and bronze against corrosion. He reported that Alexander the Great had constructed Ponton Bridge at Zeugmar on the Euphrates with the aid of an iron chain. Link's that were inserted later suffered rust attacks, While the original ones remained immune. The opinion, sometimes expressed today, that modern iron inferior and more corrosion than old iron, was thus current even in ancient times. The concept of the corrosion process derived from the latin corrodere ( to eat away, to destroy ), first appeared in the philosophical transaction in 1667. It was discussed in German from the Frensh on the manufacture of white lead in 1785 and was mentioned in 1836 in the translation of an English paper by Savy on the cathodic protection of iron in sea water. However, almost unit the present day, the term was indiscriminately for corrosion reaction effects, and corrosion damage

  6. APPLICATION OF SECONDARY MATERIALS AT PRODUCTION OF DETAILS FROM CHROME CAST IRONS

    Directory of Open Access Journals (Sweden)

    E. I. Marukovich

    2015-06-01

    Full Text Available The groups of alloy steel scrap. suitable for wear-resistant synthetic chromium and iron grades ich18VN ich18VM are studied and defined. Found that the number of alloyed steel scrap in the charge for these irons can be more than 85%, and the price of the charge decreases from 30 to 45%.

  7. 高硅合金耐热铸铁生产球墨铸铁模具的研制%Research on producing ductile iron mould with high silicon alloy heat resistant cast iron

    Institute of Scientific and Technical Information of China (English)

    梁冰利; 王宏亮; 韩黎

    2012-01-01

    对铸铁模具使用工况进行了分析,采用了高硅合金耐热铸铁为生产球墨铸铁模具的材质,并介绍了高硅合金耐热球墨铸铁模具的消失模铸造工艺、冶炼工艺、热处理工艺以及该材质模具的实际使用效果.实际生产表明:高硅合金耐热球墨铸铁具有优越的综合耐热疲劳性能,大大提高了模具寿命.%The actual operating conditions of cast iron mould were analyzed. The silicon alloy heat resistant cast iron was adopted to produce ductile iron mould, and the lost foam casting process, smelting process, heat treatment process of the high silicon alloy heat resistant ductile iron mould as well as the actual use effect of the mould with this material were introduced. The practical production shows that the high silicon alloy heat resistant cast iron has superior heat-resistant and fatigue properties, which improves the mould life.

  8. The influence of the graphite mechanical properties on the constitutive response of a ferritic ductile cast iron – A micromechanical FE analysis

    DEFF Research Database (Denmark)

    Andriollo, Tito; Thorborg, Jesper; Hattel, Jesper Henri

    2015-01-01

    In the present paper a micro-mechanical approach is used to investigate the influence of the graphite mechanical properties on the loading response in the early deformation range of ductile cast iron. A periodic unit cell composed by a single graphite nodule embedded in a uniform ferritic matrix is...

  9. Mechanism of free sulfur influence on the eutectic cell count and transition from graphite to cementite eutectic in cast iron. Part II. Experimental verification

    Directory of Open Access Journals (Sweden)

    E Fraś

    2010-01-01

    Full Text Available In this work the mechanism of free sulfur influence on the transition from graphite to cementite eutectic in cast iron is experimentally verified. It has been shown that the main impact of free sulfur on the transition from graphite to cementite eutectic consist in reducing the growth rate of graphite eutectic cell.

  10. Machinable, Thin-Walled, Gray and Ductile Iron Casting Production, Phase III

    Energy Technology Data Exchange (ETDEWEB)

    Charles Bates; Hanjun Li; Robin Griffin

    2003-12-08

    This report presents the results of research conducted to determine the effects of normal and abnormal processing and compositional variations on machinability (tool wear rate) of gray and ductile iron. The procedures developed allow precise tool wear measurements to be made and interpreted in terms of microstructures and compositions. Accurate data allows the most efficient ways for improving machinability to be determined without sacrificing properties of the irons.

  11. Development of the white cast iron with niobium alloy, heat treating, to wear of the abrasive resistance

    International Nuclear Information System (INIS)

    This work presents the heat treatment and abrasion tests results of a white cast iron with niobium alloy. The hardening heat treatment were made 950, 1000, 1050 e 110 deg C temperatures cooled by forced air. The tempering treatment were made at 450, 500 e 550 deg C temperatures. The heat treating alloy were compared, in the abrasive tests, with commercial alloys used as hardfacing by welding process in wear pieces. The abrasion tests was realized in pin on disk test. Additional tests were carried out for microstructural characterization to identify the different phases presents in the alloys. In a general way, the alloy studies showed the best wear rate for the heat treatments that results in higher hardness. It performance was superior than that of the commercial alloys. (author)

  12. 3D analysis of micro-deformation in VHCF-loaded nodular cast iron by μCT

    Energy Technology Data Exchange (ETDEWEB)

    Fischer, G., E-mail: gottfried.fischer@lqw.mb.uni-dortmund.de [RIF e.V. Institut für Forschung und Transfer, Joseph-von-Fraunhofer-Str. 20, D-44227 Dortmund (Germany); Nellesen, J., E-mail: Jens.Nellesen@rif-ev.de [RIF e.V. Institut für Forschung und Transfer, Joseph-von-Fraunhofer-Str. 20, D-44227 Dortmund (Germany); Anar, N.B., E-mail: nadeembabar.anar@tu-dortmund.de [RIF e.V. Institut für Forschung und Transfer, Joseph-von-Fraunhofer-Str. 20, D-44227 Dortmund (Germany); Ehrig, K., E-mail: Karsten.Ehrig@bam.de [BAM Bundesanstalt für Materialforschung und -prüfung, Unter den Eichen 87, D-12205 Berlin (Germany); Riesemeier, H., E-mail: Heinrich.Riesemeier@bam.de [BAM Bundesanstalt für Materialforschung und -prüfung, Unter den Eichen 87, D-12205 Berlin (Germany); Tillmann, W., E-mail: Wolfgang.Tillmann@udo.edu [Technische Universität Dortmund, Fakultät Maschinenbau, Lehrstuhl für Werkstofftechnologie, D-44221 Dortmund (Germany)

    2013-08-10

    The impact of very high cycle fatigue (VHCF) load conditions on the microstructure of specimens consisting of nodular cast iron is analyzed by means of micro-computed tomography (μCT) utilizing both monochromatic synchrotron radiation and polychromatic X-ray tube radiation. Using 3D μCT, the microstructure in the region of the smallest cross-sections of shouldered round specimens is imaged in different stages of the VHCF loading. By digital image correlation (DIC) of these tomograms strain fields are analyzed three-dimensionally. Strain levels in the range of a few percent were detected. It is proven that a localization of strain allows to predict the site of the crack which precedes and induces the macroscopic failure of the specimens.

  13. Constitutive model for flake graphite cast iron automotive brake discs: induced anisotropic damage model under complex loadings

    Science.gov (United States)

    Augustins, L.; Billardon, R.; Hild, F.

    2016-01-01

    The present paper details an elasto-viscoplastic constitutive model for automotive brake discs made of flake graphite cast iron. In a companion paper (Augustins et al. in Contin Mech Thermodyn, 2015), the authors proposed a one-dimensional setting appropriate for representing the complex behavior of the material (i.e., asymmetry between tensile and compressive loadings) under anisothermal conditions. The generalization of this 1D model to 3D cases on a volume element and the associated challenges are addressed. A direct transposition is not possible, and an alternative solution without unilateral conditions is first proposed. Induced anisotropic damage and associated constitutive laws are then introduced. The transition from the volume element to the real structure and the numerical implementation require a specific basis change. Brake disc simulations with this constitutive model show that unilateral conditions are needed for the friction bands. A damage deactivation procedure is therefore defined.

  14. Constitutive model for flake graphite cast iron automotive brake discs: from macroscopic multiscale models to a 1D rheological description

    Science.gov (United States)

    Augustins, L.; Billardon, R.; Hild, F.

    2016-07-01

    One of the critical points of the thermomechanical fatigue design process is the correct description of the cyclic behavior of the material. This work focuses on the material of automotive brake discs, namely flake graphite cast iron. The specificity of this material is its asymmetric behavior under tensile and compressive loadings, which is due to the shape of graphite that acts as small cracks. Multiscale models inspired from the literature are first presented. They lead to a good description of the material behavior under cyclic loadings. An elastoviscoplastic constitutive model is then proposed in a one-dimensional setting in order to accurately describe cyclic tests from room temperature up to {600^{circ}{C}}.

  15. Effect of Hot Deformation on Formation and Growth of Thermal Fatigue Crack in Chromium Wear Resistant Cast Iron

    Institute of Scientific and Technical Information of China (English)

    CHANG Li-min; LIU Jian-hua

    2006-01-01

    The formation and growth of thermal fatigue crack in chromium wear resistant cast iron was investigated, and the effect of hot deformation on the crack was analyzed by means of optical microscope and scanning electron microscope and high frequency induction thermal fatigue tester. The results show that eutectic carbide is the main location and passage for initiation and extension of thermal fatigue cracks, hot deformation can improve the eutectic carbide′s morphology and distribution, inhibit the generation and propagation of thermal fatigue cracks. In the experiment, the propagation rate of thermal fatigue crack reduces with the quantity of hot deformation increasing, which was analyzed in the point view of the activation energy of crack propagation.

  16. Effect of partial remelting time on the initial carbide in semisolid structure of hypereutectic hih Cr cast iron

    Directory of Open Access Journals (Sweden)

    Zhifu HUANG

    2004-11-01

    Full Text Available In order to review the effect of partial remelting time on the morphology of initial carbides, semisolid ingots of hypereutectic high Cr17 cast iron were remelted at 1 270 ℃ for four different times, and the changing characteristics of shape factor an the equivalent diameter of initial carbides were analyzed quantitatively using a Leica image analyzer. The results indicate that firstly, the evolution process of the initial carbides' morphology undergoes melting, sheroidization and refining during the partial remelting; secondly, the solute diffusion and interface tension take dominant roles at the primary and the middle-final stages respectively in the process of initial carbde evolution; finally, a perfect structure can be obtained by remeltin semisolid ingots at 1 270 ℃ for 15 min.

  17. 3D analysis of micro-deformation in VHCF-loaded nodular cast iron by μCT

    International Nuclear Information System (INIS)

    The impact of very high cycle fatigue (VHCF) load conditions on the microstructure of specimens consisting of nodular cast iron is analyzed by means of micro-computed tomography (μCT) utilizing both monochromatic synchrotron radiation and polychromatic X-ray tube radiation. Using 3D μCT, the microstructure in the region of the smallest cross-sections of shouldered round specimens is imaged in different stages of the VHCF loading. By digital image correlation (DIC) of these tomograms strain fields are analyzed three-dimensionally. Strain levels in the range of a few percent were detected. It is proven that a localization of strain allows to predict the site of the crack which precedes and induces the macroscopic failure of the specimens

  18. A New Direct-Pour In-Mold (DPI) Technology for Producing Ductile and Compacted Graphite Iron Castings.

    Energy Technology Data Exchange (ETDEWEB)

    Jason Hitchings; Jay R. Hitchings

    2007-07-20

    A new "Direct Pour In-Mold" (DPI) Magnesium treatment technology has been developed that can produce both Nodular and Compacted Graphite iron. The DPI technology converts the standard horizontal runner system into a vertical one, by placing a Magnesium Ferrosilicon treatment alloy and molten metal filter into a specially designed container. The DPI container is easily placed into either vertically or horizontally parted molds, and then a base metal can be poured directly into it. The metal is treated and filtered as it passes through, and then proceeds directly into a runner or casting cavity. Various sizes of containers provide all of the necessary components required to deliver a range of weights of treated and filtered metal at accurate and consistent flow rates. The DPI containers provide energy savings over competing techniques, increased mold yields, very high Magnesium recovery, zero Magnesium fume, and no post inoculation is required. By treating the metal just prior to it entering a casting cavity many other benefits and advantages are also realized.

  19. Effects of moisture in the air on characteristics of strength in high strength spheroidal graphite cast iron

    International Nuclear Information System (INIS)

    The purpose of this study is to investigate the effects of humidity on the strength characteristics in high strength spheroidal graphite cast iron with two phases, which is ferrite and pearlite. Three spheroidal graphite cast irons (FCD400(FDI), FCD500(FPDI.82) and FCD600(FPDI.55)) were used as specimens. In addition, heat treatment (Normalizing) was conducted in FCD500 (PDI). Tensile test conforming to JIS was carried out using these resultant four materials in air and water. The specimen used was of the 14A type. The relationship between tensile strength and area ratio of brittle fracture was investigated. Fatigue crack propagation test conforming to ASTM was also carried out using these materials. Stress ratio R was 0.1, and the specimen used was of the 1CT type with a thickness of 12.5 mm. The test was carried out at room temperature and three kinds of humidity: 0, 40 and 80%. The relationship between the characteristics of fatigue crack propagation and crack closure generated on the fracture surface was investigated. Though tensile strength in FDI and FPDI.82 was not influenced by water brittlement, strength in PDI and FPDI.55, which included pearlite, was decreased by water brittlement. This phenomenon may mainly be caused by the amount of parlite in the matrix. The threshold stress intensity factor range ΔKth of all materials increased with increasing humidity. Crack closure was investigated in all materials. It seemed to become marked with increasing humidity. In the low ΔKeff region of all materials (except FPDI.55, 80%), the fatigue crack propagation rate was almost the same because of oxide-induced crack closure of the ferrite included in the matrix. In the high ΔKeff region of FPDI and PDI, the rate was not the same. The acceleration was investigated because of effect of a phenomenon similar to the water embrittlement of pearlite included in the matrix. (author)

  20. Iron Melt Flow in Thin Walled Sections Cast in Vertically Parted Green Sand Moulds

    DEFF Research Database (Denmark)

    Larsen, Per; Andersen, Uffa; Rasmussen, Niels

    solely by the geometry of the runners. A non-conventional gating system has also been tested. The system gives a high degree of control over the flow, the balance between the dynamic and braking forces have only little influence on the flow patterns. An exhaust manifold with 2 mm wall thickness has been...... casting thin walled parts, as thin plate shaped ingates are used for casting many parts. This is illustrated with a brake disc. 6 layouts have been made. The filling sequences have been recorded on video. The trials show the difficult task to design a bottom filling system generating no splash during the...... high velocities can still result in calm flow with coherent melt fronts. Conventional types of gating systems have been used for 5 of the 6 layouts. The flow patterns in these systems are to a large degree controlled by the relative sizes of the dynamic and braking forces acting on the melt and not...

  1. Aluminium composite casting dispersion reinforced with iron-aluminium and silicon carbide phases

    Directory of Open Access Journals (Sweden)

    B. Formanek

    2010-10-01

    Full Text Available Aluminium matrix composite with dispersion-reinforced, made by similar to stircasting process was characterised. The mixture of powders was produced by the process of mechanical agglomeration of powdered FexAly and SiC with aluminium. The chemical composition ofagglomerates was selected in a way such as to obtain 25 wt.% reinforcement of the AlSi9Cu4 silumin matrix. Applying thermal analysis ATD, the alloy solidification process was determined, reading out the typical solidification parameters. The methods of light and scanning microscopy were used to reveal the structure of composite casting. Changes in chemical composition and phase composition of particles of the FeAl intermetallic phase in aluminium matrix were confirmed. The structure of silumin casting with matrix containing microregions of ceramic and intermetallic phases, typical of hybrid reinforcements, was obtained.

  2. The role of iron in the formation of porosity in Al-Si-Cu-based casting alloys. Part 2: A phase-diagram approach

    Energy Technology Data Exchange (ETDEWEB)

    Taylor, J.A.; Schaffer, G.B.; StJohn, D.H. [Univ. of Queensland, Brisbane (Australia)

    1999-06-01

    The mechanism by which iron causes casting defects in the AA309 (Al-5 pct Si-1.2 pct Cu-0.5 pct Mg) may be related to the solidification sequence of the alloy. Superimposing calculated segregation lines on the liquidus projection of the ternary Al-Si-Fe phase diagram suggests that porosity is minimized at a critical iron content when solidification proceeds directly from the primary field to the ternary Al-Si-{beta}Al{sub 5}FeSi eutectic point. Solidification via the binary Al-{beta}Al{sub 5}FeSi eutectic is detrimental to casting integrity. This hypothesis was tested by comparing the critical iron content observed in the standard AA309 alloy to that of a high-silicon (10 pct Si) variant of this alloy.

  3. APPLICATION OF SPHEROIDIZING «CHIPS»-MASTER ALLOY ON COPPER BASE CONTAINING NANOSCALE PARTICLES OF YTTRIUM OXIDE FOR HIGH-STRENGTH CAST IRON

    Directory of Open Access Journals (Sweden)

    A. S. Kalinichenko

    2016-04-01

    Full Text Available The peculiarity of the technology of obtaining high-strength cast iron is application in out-furnace treatment various inoculants containing magnesium. In practice of foundry production spheroidizing master alloys based on ferrosilicon (Fe-Si-Mg type and «heavy» alloying alloys on copper and nickel base are widespread. The urgent issue is to improve their efficiency by increasing the degree of magnesium assimilation, reduction of specific consumption of additives, and minimizing dust and gas emissions during the process of spheroidizing treatment of liquid iron. One method of solving this problem is the use of inoculants in a compact form in which the process of dissolution proceeds more efficiently. For example, rapidly quenched granules or «chip»-inoculants are interesting to apply.The aim of present work was to study the peculiarities of production and application of «Chips»-inoculants on copper and magnesium base with additions of yttrium oxide. The principle of mechatronics was used, including the briquetting inoculants’ components after their mixing with the subsequent high-speed mechanical impact and obtaining plates with a thickness of 1–2 mm.Spheroidizing treatment of molten metal has been produced by ladle method using «Chips»-inoculants in the amount of 0.8%. Secondary graphitization inoculation was not performed. Studies have shown that when the spheroidizing treatment of ductile iron was performed with inoculants developed, the process of interaction of magnesium with the liquid melt runs steadily without significant pyroeffect and emissions of metal outside of the ladle.This generates a structure of spheroidal graphite of regular shape (SGf5. The presence in the inoculant of yttrium oxide has a positive impact on the spheroidal graphite counts and the tendency of high-strength cast iron to form «white» cast iron structure. Mechanical properties of the obtained alloy correspond to high-strength cast iron HSCI60.

  4. Effect of austempering parameters on microstructure and mechanical properties of horizontal continuous casting ductile iron dense bars

    Directory of Open Access Journals (Sweden)

    Chun-jie Xu

    2015-03-01

    Full Text Available In the present research, the orthogonal experiment was carried out to investigate the influence of different austempering process parameters (i.e. austenitizing temperature and time, and austempering temperature and time on microstructure and mechanical properties of LZQT500-7 ductile iron dense bars with 172 mm in diameter which were produced by horizontal continuous casting (HCC. The results show that the major factors influencing the hardness of austempered ductile iron (ADI are austenitizing temperature and austempering temperature. The fraction of retained austenite increases as the austenitizing and austempering temperatures increase. When austenitizing temperature is low, acicular ferrite and retained austenite can be efficiently obtained by appropriately extending the austenitizing time. The proper austmepering time could ensure enough stability of retained austenite and prevent high carbon austenite decomposition. The optimal mechanical properties of ADI can be achieved with the following process parameters: austenitizing temperature and time are 866 °C and 135 min, and austempering temperature and time are 279 °C and 135 min, respectively. The microstructure of ADI under the optimal austempering process consists of fine acicular ferrite and a small amount of retained austenite, and the hardness, tensile strength, yield strength, elongation and impact toughness of the bars are HBW 476, 1670 MPa, 1428 MPa, 2.93% and 25.7 J, respectively.

  5. Microstructure and Wear Behavior of TiC Coating Deposited on Spheroidized Graphite Cast Iron Using Laser Surfacing

    Directory of Open Access Journals (Sweden)

    E. R. I. Mahmoud

    2014-10-01

    Full Text Available Spheroidal graphite cast iron was laser cladded with TiC powder using a YAG fiber laser at powers of 700, 1000, 1500 and 2000 W. The powder was preplaced on the surface of the specimens with 0.5 mm thickness. Sound cladding and fusion zones were observed at 700, 1000 and 1500 W powers. However, at 2000 W, cracking was observed in the fusion zone. At 700 W, a build-up zone consisted of fine TiC dendrites inside a matrix composed of martensite, cementite (Fe3C, and some blocks of retained austenite was observed. In this zone, all graphite nodules were totally melted. In the fusion zone, some undissolved and partially dissolved graphite nodules appeared in a matrix containing bainite, ferrite, martensite and retained austenite. At 1500 W, the fusion zone had more iron carbides and ferrite, and the HAZ consisted of martensitic structure. At 2000 W, the build-up zone was consisted of TiC particles precipitated in a matrix of eutectic carbides, martensite plus an inter-lamellar retained austenite. The hardness of the cladded area was remarkably improved (1330 HV in case of 700 W: 5.5 times of the hardness of substrate

  6. Low temperature impact toughness and fracture mechanism of cast QT400-18L ductile iron with different Ni additions

    Directory of Open Access Journals (Sweden)

    Zhang Xinning

    2013-09-01

    Full Text Available Different contents of Ni (0.3wt.% to 1.2wt.% were added to the QT400-18L ductile iron to investigate the effect of Ni addition on the impact toughness of cast ductile irons at low temperatures. The impact toughnesses of the samples at room and low temperatures were tested. The microstructures and fractographs were observed. Results show that with the increase of Ni addition there is a general trend of refinement of the ferrite matrix while the nodule density shows no obvious change. When the Ni content is 0.7wt.%, the matrix structure is the refined ferrite with a very small fraction (about 2% of pearlite near the eutectic cell boundaries. When the Ni content is further increased, the fraction of pearlite increases significantly and reaches more than 5% when 1.2wt.% Ni is added. The impact toughness at room temperature increases as the content of Ni increases from 0.3 wt.% to 0.7 wt.%, but decreases as the Ni content further increases to 1.2wt.% due to the increase of pearlite fraction. The maximum value of the impact work is 18.5 J at room temperature with 0.7wt.% Ni addition. The average value of the impact work is still more than 13 J even at -30 ℃. In addition, the fracture mechanism changes from ductile manner to brittleness as the testing temperature decreases from 20 ℃ to -60 ℃.

  7. Effect of electrical pulse treatment on the thermal fatigue resistance of bionic compacted graphite cast iron processed in water

    International Nuclear Information System (INIS)

    Highlights: ► Electrical pulse treatment can reduce cracks on bionic units before thermal fatigue tests. ► Electrical pulse treatment can reduce crack sources during thermal fatigue tests. ► Thermal fatigue resistance of bionic units processed in water is enhanced. ► Thermal fatigue resistance of bionic CGI processed in water is improved. -- Abstract: In order to further enhance the thermal fatigue resistance of bionic compacted graphite cast iron (CGI) which is processed by laser in water, the electrical pulse treatment is applied to improve the thermal fatigue resistance of bionic units. The results show that the electrical pulse treatment causes the supersaturated carbon atoms located in the lattice of austenite to react with the iron atoms to form the Fe3C. The microstructures of the bionic units processed in water are refined by the electrical pulse treatment. The cracks on the bionic units are reduced by the electrical pulse treatment before the thermal fatigue tests; and during the tests, the thermal fatigue resistance of bionic units is therefore enhanced by reducing the crack sources. By this way, the thermal fatigue resistance of bionic CGI processed in water is improved.

  8. 铸造铝合金叶轮嵌铸铸铁轮芯结构设计及工艺要点%Structural Design and Process Essentials of Inlay Casting Iron Core in Cast Aluminum Impeller

    Institute of Scientific and Technical Information of China (English)

    洪美琴; 尹社新

    2011-01-01

    Inlay casting iron core sometimes looses in axial direction from the running cast aluminum impeller, then the fan will cause fault such as vibration and abnormal voice etc. The effects of the two different configurations of the cast aluminum iron core on the quality of the impeller were analyzed in this paper. Structural design of inlay core and casting technology of impeller were briefly explained.%采用嵌铸铸铁轮芯的铸造铝合金叶轮在运行中有时出现轴向松动的现象,使运转中的风机产生振动、异音等故障.文中对铸造铝合金叶轮中嵌铸铸铁轮芯的两种不同结构对叶轮质量的影响进行了分析,阐述了铸造铝合金叶轮中嵌铸铸铁轮芯的结构设计和工艺要点.

  9. The shaping of zinc coating on surface steels and ductile iron casting

    OpenAIRE

    D. Kopyciński

    2010-01-01

    The studies aimed at an analysis of the formation and growth kinetics of zinc coating on reactive silicon-killed steels in a zinc bath. The growth kinetics of the produced zinc coatings was evaluated basing on the power-law growth equation. As regards galvanizing of the surface of products, investigation was done for various steel grades and ductile iron (DI) taking into account the quality and thickness of coating. It has been proved that the chemical constitution of basis significantly infl...

  10. Characterisation of the fatigue properties of cast irons used in the water industry and the effect on pipe strength and performance

    International Nuclear Information System (INIS)

    As part of an on going programme to characterise the residual properties and understand the failure mechanisms of in-service grey cast iron water pipes, the fatigue crack propagation behaviour of grey cast iron samples has been studied. Specimens were sourced from three ex-service pipes. For each pipe the microstructure and composition were characterised and the fracture toughness was determined. The fatigue behaviour was investigated in terms of the crack growth rate (da/dN) as a function of the applied stress intensity factor range. Clear differences in the fatigue behaviour of the samples from different pipes were observed. The result from these investigations, which indicate that microstructural differences play a role in mechanical behaviour, will support the development of asset management tools for use in the water industry.

  11. Residual Stress, Structure and Other Properties Formation by Combined Thermo-Hardening Processing of Surface Layer of Gray Cast Iron Parts

    Science.gov (United States)

    Rakhimyanov, Kh M.; Nikitin, Yu V.; Semenova, Yu S.; Eremina, A. S.

    2016-04-01

    The proposed combined thermo-hardening processing of gray cast iron enables to control the surface layer structure and mechanical properties formation. The processing includes high-speed heating by low-temperature plasma source and ultrasonic surface plastic deformation. The algorithm of calculation the stress-strain state of a surface layer at combined processing of gray cast iron is developed. This algorithm is based on method of sections. The ultrasonic surface deformation contribution is determined during formation of residual stresses. It is established that the combination of the thermal and deformation effects on the material provides an additional increment of microhardness and increase of surface layer thickness. Experimental results shows that the features of structural and phase transformations in a surface layer are revealed without a surface melting by energy of low-temperature plasma. The top of a layer does not contain inclusions of graphite that testifies to change of structural transformations in conditions of combined processing.

  12. Study on laser-cladding Ni-Al-WC alloy layer on the surface of chrome cast iron and alloy layer's micro-structure and properties

    International Nuclear Information System (INIS)

    Laser-cladding Ni-Al-WC alloy layer on the surface of chrome cast iron and alloy layer's micro-structure and properties are studied. The chemical composition, the phase structure, the average micro-hardness, the wear resistance and the corrosion resistance are analyzed for the Ni-Al-WC and the matrix, respectively. The results show that the metallurgical combination is achieved between the spray alloy layer and the surface of chrome cast iron, the chemical composition and micro-structure in the surface layer of the specimen are changed basically, and the micro-hardness, the wear resistance, the corrosion resistance in the surface layer are increased with a large range

  13. Performance evaluation of cast iron pipe for crude oil and salt water transportation; Avaliacao e desempenho de duto de aco fundido no transporte de petroleo com aguas salgadas

    Energy Technology Data Exchange (ETDEWEB)

    Silva, Carlos Alexandre Martins da [PETROBRAS Transporte S.A. (TRANSPETRO), Rio de Janeiro, RJ (Brazil); Mainier, Fernando B. [Universidade Federal Fluminense, Niteroi, RJ (Brazil)

    2005-07-01

    The present paper aims to study and to evaluate the performance of casting iron pipe for transportation of salty and produced waters, presented in the oil industry, where salt contents ranging on very large values. The cast iron above mentioned has an yield strength of 23 kg/mm{sup 2}, tensile strength of de 46 kg/mm{sup 2} (minimum) and an elongation of 15%, and contents of some chemical alloys, such as Cr (0,8 -1,3 %), Mn (1,5 % max) and Si (1,%). Nevertheless it is an exploratory study, the dynamic tests of weight loss carried out in laboratory, with specimens machined from a used pipe piece, with salty solution (3,5 % NaCl) aerated media, has shown very promising results, enabling to qualify, satisfactorily, such material for using in transportation and transferring operations of fluids with a high salty contents, such as crude oil. (author)

  14. Atmospheric corrosion rate expressed as a function of time. Effects of atmospheric conditions and alloying elements on corrosion resistance of steels and cast irons

    International Nuclear Information System (INIS)

    On the basis of function describing a change in atmospheric corrosion rate (K) in time (t) the published results of long-standing corrosion tests of a great number of cast irons and steels were statistically processed. The effect of chloride - ions, sulfur dioxide, alloying elements (Cu, Ni, Cr, Mn, Si, V, C) on the rate of initial corrosion on the active surface (K0), passivation properties (α0) of corrosion products and corrosion resistance (α0/K0) of iron-carbonic alloys in different climatic areas was revealed. The data permit further investigation of the mechanism of alloying element effect on atmopsheric corrosion of steels

  15. Mechanochemical reactions and strengthening in epoxy-cast aluminum iron-oxide mixtures

    Science.gov (United States)

    Ferranti, Louis, Jr.

    2007-12-01

    Epoxy-cast Al+Fe2O3 thermite composites are an example of a structural energetic material that can simultaneously release chemical energy while providing structural strength. The structural/mechanical response and chemical reaction behavior are closely interlinked through characteristics of deformation and intermixing of reactants. In this work, the structural and energetic response of composites made from stoichiometric mixtures of nano- and micro-scale aluminum and hematite (Fe2O3) powders dispersed in 47 to 78 vol.% epoxy was investigated by characterizing the mechanical behavior under high-strain rate and shock loading conditions. The main focus of the work was to understand the influence of microstructure on mechanical behavior in epoxy-cast Al+Fe2O3 materials when exposed to high stress, large strain, and high rate loading conditions. The material's Hugoniot at pressures up to approximately 20 GPa for an Al+Fe2O3+78 vol.% epoxy composite and up to approximately 8 GPa for Al+Fe2O3+60 vol.% epoxy composite has been determined. The results reveal an inert pressure-relative volume (P-V) and shock-particle velocity (US-UP) response in the range of the shock-conditions explored, with the Al+Fe2O3+60 vol.% epoxy composite showing a greater shock stiffness. The addition of solid particle inclusions alters the Hugoniot response as compared to pure epoxy behavior. This is attributed to possible induced bulk damage that changes the composite's response as impact stress increases. While the 78 vol.% epoxy composition shows a transition from "undamaged" to "damaged" behavior that approaches pure epoxy response, the 60 vol.% epoxy composition exhibits a gradual toughening behavior. Impact experiments have also been conducted for characterizing the high-strain rate deformation and fracture response obtained from instrumented reverse Taylor tests using high-speed camera and velocity interferometry. The results show that these composite materials exhibit viscoelastic

  16. 发动机球墨铸铁连杆疲劳强度分析%Analysis on Fatigue Strength of Nodular Cast Iron Connecting Rod in Engi

    Institute of Scientific and Technical Information of China (English)

    包雪鹏; 袁文; 武庆; 吴晓翔

    2001-01-01

    发动机连杆采用高强韧性球墨铸铁制造。介绍了采用小子样升降法试验该种发动机球墨铸铁连杆疲劳强度的方法和结果,预测了不同存活率下连杆的疲劳强度,分析了疲劳断口特征,指出夹渣、气孔和疏松等铸造缺陷是造成连杆失效的主要原因,如不存在铸造缺陷,疲劳裂纹起源于工字筋中心的显微疏松处。%The engine connecting rod is made by a nodular cast iron with high strength and toughness. This paper describes the methods and results of testing the fatigue strength of engine nodular cast iron connecting rod by small subsample lift and drop method, predicts the fatigue strength of connecting rod under different survival rates and analyzes the character of fatigue rupture notch. It is noted that the casting defects like inclusions, gas holes, looseness and etc. are main factors to cause the failure of connecting rods. The fatigue cracks sourced in looseness location in micro - structure of I shape rib center if casting defects do not exist

  17. Mechanical and Tribological Properties of HVOF-Sprayed (Cr3C2-NiCr+Ni) Composite Coating on Ductile Cast Iron

    Science.gov (United States)

    Ksiazek, Marzanna; Boron, Lukasz; Radecka, Marta; Richert, Maria; Tchorz, Adam

    2016-07-01

    The aim of the investigations was to compare the microstructure, mechanical, and wear properties of Cr3C2-NiCr+Ni and Cr3C2-NiCr coatings deposited by HVOF technique (the high-velocity oxygen fuel spray process) on ductile cast iron. The effect of nickel particles added to the chromium carbide coating on mechanical and wear behavior in the system of Cr 3 C 2 -NiCr+Ni/ductile cast iron was analyzed in order to improve the lifetime of coated materials. The structure with particular emphasis of characteristic of the interface in the system of composite coating (Cr 3 C 2 -NiCr+Ni)/ductile cast iron was studied using the optical, scanning, and transmission electron microscopes, as well as the analysis of chemical and phase composition in microareas. Experimental results show that HVOF-sprayed Cr3C2-NiCr+Ni composite coating exhibits low porosity, high hardness, dense structure with large, partially molten Ni particles and very fine Cr3C2 and Cr7C3 particles embedded in NiCr alloy matrix, coming to the size of nanocrystalline. The results were discussed in reference to examination of bending strength considering cracking and delamination in the system of composite coating (Cr 3 C 2 -NiCr+Ni)/ductile cast iron as well as hardness and wear resistance of the coating. The composite structure of the coating provides the relatively good plasticity of the coating, which in turn has a positive effect on the adhesion of coating to the substrate and cohesion of the composite coating (Cr3C2-NiCr+Ni) in wear conditions.

  18. Tribological properties of AlN-CeO2-Si3N4 cutting materials in unlubricated sliding against tool steel and cast iron

    OpenAIRE

    Gomes, J. R.; Miranda, A. S.; Silva, R F; J. M. Vieira

    1996-01-01

    Ceramic pins of the AIN-CeO2-Si3N4 system were tested in a pin-on-disc tribometer against discs of tool steel and grey cast iron, at room temperature, without lubrication, in different conditions of humidity and sliding speed. Ceramic samples were selected on the basis of their mechanical properties (hardness and fracture toughness), and microstructural characteristics, namely porosity, volume of intergranular phase and nitrogen content of the glass phase. Water vapour increased the ...

  19. Directional solidification of flake and nodular cast iron during KC-135 low-g maneuvers

    Science.gov (United States)

    Curreri, P. A.; Stefanescu, D. M.; Hendrix, J. C.

    1984-01-01

    Alloys solidified in a low-gravity environment can, due to the elimination of sedimentation and convection, form unique and often desirable microstructures. One method of studying the effects of low-gravity (low-g) on alloy solidification was the use of the NASA KC-135 aircraft flying repetitive low-g maneuvers. Each maneuver gives from 20 to 30 seconds of low-g which is between about 0.1 and 0.001 gravity. A directional solidification furnace was used to study the behavior of off eutectic composition case irons in a low-g environment. The solidification interface of hypereutectic flake and spheroidal graphite case irons was slowly advanced through a rod sample, 5 mm in diameter. Controlled solidification was continued through a number of aircraft parabolas. The known solidification rate of the sample was then correlated with accelerometer data to determine the gravity level during solidification for any location of the sample. The thermal gradient and solidification rate were controlled independently. Samples run on the KC-135 aircraft exhibited bands of coarser graphite or of larger nodules usually corresponding to the regions solidified under low-g. Samples containing high phosphorous (used in order to determine the eutectic cell) exhibited larger eutectic cells in the low-g zone, followed by a band of coarser graphite.

  20. Effects of the Exposure to Corrosive Salts on the Frictional Behavior of Gray Cast Iron and a Titanium-Based Metal Matrix Composite

    Energy Technology Data Exchange (ETDEWEB)

    Blau, Peter Julian [ORNL; Truhan, Jr., John J [ORNL; Kenik, Edward A [ORNL

    2007-01-01

    The introduction of increasingly aggressive road-deicing chemicals has created significant and costly corrosion problems for the trucking industry. From a tribological perspective, corrosion of the sliding surfaces of brakes after exposure to road salts can create oxide scales on the surfaces that affect friction. This paper describes experiments on the effects of exposure to sodium chloride and magnesium chloride sprays on the transient frictional behavior of cast iron and a titanium-based composite sliding against a commercial brake lining material. Corrosion scales on cast iron initially act as abrasive third-bodies, then they become crushed, spread out, and behave as a solid lubricant. The composition and subsurface microstructures of the corrosion products on the cast iron were analyzed. Owing to its greater corrosion resistance, the titanium composite remained scale-free and its frictional response was markedly different. No corrosion scales were formed on the titanium composite after aggressive exposure to salts; however, a reduction in friction was still observed. Unlike the crystalline sodium chloride deposits that tended to remain dry, hygroscopic magnesium chloride deposits absorbed ambient moisture from the air, liquefied, and retained a persistent lubricating effect on the titanium surfaces.

  1. Study on Friction and Wear Characteristics and Structure of Compound Layer from Combined Treatment of Ion Nitrocarburizing-Ion Sulphurizing of CrMoCu Alloy Cast Iron

    Institute of Scientific and Technical Information of China (English)

    MAShi-ning; HUChun-hua; LIXin; QIUJi

    2004-01-01

    The technics of combined treatment of ion nitrocarburizing-ion sulpburizing of CrMoCu alloy cast iron has been investigated and the compound layer with nitrocabonide and sulphide has been made on the surface of CrMoCu alloy cast iron. The compound layer is composed of sulfide surface layer and the nitrocarbonide hypo-surface layer and its diffusing laye. The size of sulfide globular grains distributing equably on the surface is in nano-micmn-scale, and the phase structure of the compound layer is composed of FeS, FeS2, Fe2C and FerN. Under dry sliding condition, the friction-reducing of sulphurized surface is good, but its function time can't last vet3. long, The nitrocarbonided+sulphurized surface can gready improve the wear-resistance and the friction-reducing of CrMoCu alloy cast iron, and its integrated friction and wear properties are better than plain and sulphurized surfaces.

  2. Study on Friction and Wear Characteristics and Structure of Compound Layer from Combined Treatment of Ion Nitrocarburizing-Ion Sulphurizing of CrMoCu Alloy Cast Iron

    Institute of Scientific and Technical Information of China (English)

    MA Shi-ning; HU Chun-hua; LI Xin; QIU Ji

    2004-01-01

    The technics of combined treatment of ion nitrocarburizing-ion sulphurizing of CrMoCu alloy cast iron has been investigated and the compound layer with nitrocarbonide and sulphide has been made on the surface of CrMoCu alloy cast iron. The compound layer is composed of sulfide surface layer and the nitrocarbonide hypo-surface layer and its diffusing layer. The size of sulfide globular grains distributing equably on the surface is in nano-micron-scale, and the phase structure of the compound layer is composed of FeS、 FeS2、 Fe2C and Fe3N. Under dry sliding condition, the friction-reducing of sulphurized surface is good, but its function time can't last very long. The nitrocarbonided+sulphurized surface can greatly improve the wear-resistance and the friction-reducing of CrMoCu alloy cast iron, and its integrated friction and wear properties are better than plain and sulphurized surfaces'.

  3. Damage Analysis of a Ferritic SiMo Ductile Cast Iron Submitted to Tension and Compression Loadings in Temperature

    Directory of Open Access Journals (Sweden)

    Isabel Hervas

    2015-12-01

    Full Text Available Tensile and compression tests were carried out on a ductile cast iron for temperatures up to 1073 K. The damage caused inside and around graphite nodules was evaluated as a function of the local equivalent plastic strain by using microstructural quantifications. The mechanical properties are strongly dependent on a temperature above 773 K. Concerning tensile behavior, an evolutional law issued from the Gurson model representing the void growth as a function of the deformation and temperature was successfully employed. It is demonstrated that the strain state and the temperature have a strong influence on the void growth function. In the case of compression tests, the temperature has a weak influence on the nodule deformation for temperatures lower than 773 K, and the mechanical behavior is driven by the viscoplastic properties of the ferrite. For higher temperatures, the mechanical properties in compression are progressively modified, since graphite nodules tend to remain spherical, and ferrite grains are severely deformed. A synthesis of the damage mechanisms is proposed in the studied range of temperature and plastic strain. It appears that the graphite nodule aspect ratio can be used as an indicator of the deformation under compression loading for temperatures ranging from room temperature to 673 K.

  4. Effects of bionic units on the fatigue wear of gray cast iron surface with different shapes and distributions

    Science.gov (United States)

    Chen, Zhi-kai; Lu, Shu-chao; Song, Xi-bin; Zhang, Haifeng; Yang, Wan-shi; Zhou, Hong

    2015-03-01

    To improve the fatigue wear resistance of gray cast iron (GCI), GCI samples were modified by a laser to imitate the unique structure of some soil animals alternating between soft and hard phases; the hard phase resists the deformation and the soft phase releases the deformation. Using the self-controlled fatigue wear test method, the fatigue wear behaviors of treated and untreated samples were investigated and compared experimentally. The results show that the bionic non-smooth surface obtains a beneficial effect on improving the fatigue wear resistance of a sample, and the fatigue wear resistance of the bionic sample assembled with reticulate units (60°+0°), whose mass loss was reduced by 62%, was superior to the others. Meanwhile, a finite element (FE) was used to simulate the compression and the distributions of strain and stress on the non-smooth surface was inferred. From these results, we understood that the functions of the bionic unit such as reducing strain and stress, and also obstructing the closure and propagation of cracks were the main reasons for improving the fatigue wear property of GCI.

  5. Effect of medium on friction and wear properties of compacted graphite cast iron processed by biomimetic coupling laser remelting process

    International Nuclear Information System (INIS)

    Stimulated by the cuticles of soil animals, an attempt to improve the wear resistance of compact graphite cast iron (CGI) with biomimetic units on the surface was made by using a biomimetic coupled laser remelting process in air and various thicknesses water film, respectively. The microstructures of biomimetic units were examined by scanning electron microscope and X-ray diffraction was used to describe the microstructure and identify the phases in the melted zone. Microhardness was measured and the wear behaviors of biomimetic specimens as functions of different mediums as well as various water film thicknesses were investigated under dry sliding condition, respectively. The results indicated that the microstructure zones in the biomimetic specimens processed with water film are refined compared with that processed in air and had better wear resistance increased by 60%, the microhardness of biomimetic units has been improved significantly. The application of water film provided finer microstructures and much more regular grain shape in biomimetic units, which played a key role in improving the friction properties and wear resistance of CGI.

  6. Effect of scanning speed during PTA remelting treatment on the microstructure and wear resistance of nodular cast iron

    Institute of Scientific and Technical Information of China (English)

    Hua-tang Cao; Xuan-pu Dong; Qi-wen Huang; Zhang Pan; Jian-jun Li; Zi-tian Fan

    2014-01-01

    The surface of nodular cast iron (NCI) with a ferrite substrate was rapidly remelted and solidified by plasma transferred arc (PTA) to induce a chilled structure with high hardness and favorable wear resistance. The effect of scanning speed on the microstructure, micro-hardness distribution, and wear properties of PTA-remelted specimens was systematically investigated. Microstructural characterization in-dicated that the PTA remelting treatment could dissolve most graphite nodules and that the crystallized primary austenite dendrites were transformed into cementite, martensite, an interdendritic network of ledeburite eutectic, and certain residual austenite during rapid solidifica-tion. The dimensions of the remelted zone and its dendrites increase with decreased scanning speed. The microhardness of the remelted zone varied in the range of 650 HV0.2 to 820 HV0.2, which is approximately 2.3-3.1 times higher than the hardness of the substrate. The wear re-sistance of NCI was also significantly improved after the PTA remelting treatment.

  7. Nb在灰铸铁中的存在形态%Existing Morphologies of Niobium in Cast Irons

    Institute of Scientific and Technical Information of China (English)

    朱洪波; 孙小亮; 闫永生; 华勤; 翟启杰

    2011-01-01

    The existing morphologies of niobium in cast irons were mvestigated by using SEM with spectroscopy. The result showed that only a little quantity of niobium dissolved as the atom type in the matrix and formed solid solution.however most of the niobium formed the Nb-rich phase embedding into the matrix;the Nb-rich phase had a lots of morphologies such as the clump shape (including square and triangle shape),abnormal shape (including Ⅹ type and Ⅴ type).and bar shape. TiN could act as the heterogeneous crystal nucleus in the forming process of the Nb-rich phase and,therefore,it had the effect to promote the formation of the Nb-rich phase.%用附带能谱的扫描电镜研究了Nb在灰铸铁中的存在形态,结果显示:少量Nb以原子形式固溶于基体,绝大多数Nb形成富Nb相镶嵌在基体上面;富Nb相形态丰富,有块状(包括方块状和_一角形)、不规则形状(包括X型、Y型)以及条棒状;在富Nb相形成过程中,TiN可能作为异质核心,因而对富Nb相的形成起了促进作用.

  8. Effects of different inoculants on the microstructural characteristics of gray cast iron gg-25, hardness and useful life of tools

    Directory of Open Access Journals (Sweden)

    Diego Ruben Martin

    2015-10-01

    Full Text Available Current study evaluated the machinability characteristics of parts, microstructure and mechanical properties when three different inoculants (IM-22 with FeSi-Ba/Zr; G-20 and FeSi-Ba; IMSR 75 with FeSi-Sr were added in experiments carried out in a foundry. The research methodology was mailly based on the analysis of the machinability by the milling process of the specimens in gray cast iron GG-25, name according to DIN EN 1561.Evaluation of results is based on a thorough analysis of tool wear, surface finish, microstructural analysis, chemical composition and mechanical properties of the material. Results showed that among the studied inoculants strontium sulfide (SrS was thermodynamically more stable than the others, because it leds towards a more negative free energy change of Gibbs and therefore more favorable to the formation of nuclei having greater critical radius (rc, solidification with heterogeneous nucleation. Its inoculant was also more efficient in forming a more favorable microstructure, greater amounts of eutectic cells and, longer life of the insert when machined.

  9. Wear and Corrosion Resistance of Fe Based Coatings by HVOF Sprayed on Gray Cast-Iron for Automotive Application

    Directory of Open Access Journals (Sweden)

    M.S. Priyan

    2014-12-01

    Full Text Available In this study, commercially available FeSiNiCr and FeBCr alloy powders were designed with suitable compositions, gas atomized and then coated on gray cast-iron substrate. The microstructures of the feed stock Fe based alloy powders and the coatings were investigated by means of optical microscopy (OM, X-Ray diffraction (XRD, Thermogravimetric analysis (TGA and Scanning Electron Microscopy (SEM. In the present study, both the coating materials experienced two-body wear mechanisms. The results showed that for loads of 0.05 N, 0.1 N and 0.2 N, the wear resistance of FeBCr coating was less than FeSiNiCr by 44 %, 40 % and 31 %, respectively. The results indicated that the coated substrates exhibited lower corrosion current densities and lower corrosion rates, when placed in 20 wt.% H2SO4 solutions. In addition, the use of optimal spraying parameters/conditions gave improvements to the corrosion resistance of the substrates that had been treated with the crystalline coating.

  10. Influence of Orientations of Bionic Unit Fabricated by Laser Remelting on Fatigue Wear Resistance of Gray Cast Iron

    Science.gov (United States)

    Chen, Zhi-Kai; Zhou, Ti; Zhang, Hai-feng; Yang, Wan-shi; Zhou, Hong

    2015-06-01

    Fatigue wear resistance improvements were researched by studying experimental samples with gray cast iron fabricated with bionic units in different orientations. Experimental samples were modified by laser surface remelting, including parallel, vertical, and gradient units to the wear direction. The remelting pool was then studied to determine the micro-hardness, microstructure, alteration of phase, and etc. Lab-control fatigue wear test method was applied with the treated and untreated samples tested under the laboratorial conditions. Wear resistance result was considered as the rolling contact fatigue (RCF) resistance and mechanisms of the modified samples were experimentally investigated and discussed. Results suggested that all treated samples demonstrated the beneficial effect on the RCF improvement due to lack of graphite and reinforcement of treated region. Results also indicated the sample with fastigiated units was more effective than that with vertical units or parallel units to the wear direction. Influence of the sample unit's angle which intensely depended on the conditions of actual application, however, was not identified.

  11. Effect of thermal fatigue on the wear resistance of graphite cast iron with bionic units processed by laser cladding WC

    Science.gov (United States)

    Jing, Zhengjun; Zhou, Hong; Zhang, Peng; Wang, Chuanwei; Meng, Chao; Cong, Dalong

    2013-04-01

    Thermal fatigue and wear exist simultaneously during the service life of brake discs. Previous researchers only studied thermal fatigue resistance or abrasion resistance of compact graphite cast iron (CGI), rather than combining them together. In this paper, wear resistance after thermal fatigue of CGI was investigated basing on the principle of bionics, which was close to actual service condition of the brake discs. In the meanwhile, the effect of thermal fatigue on wear resistance was also discussed. Non-smooth bionic units were fabricated by laser cladding WC powder with different proportions (50 wt.%, 60 wt.%, 70 wt.%). Microstructure and microhardness of the units were investigated, and wear mass losses of the samples were also compared. The results indicate that thermal fatigue has a negative effect on the wear resistance. After the same thermal fatigue cycles times, the wear resistance of laser cladding WC samples is superior to that of laser remelting ones and their wear resistance enhances with the increase of WC content.

  12. Evaluation of Surface Roughness and Power Consumption in Machining FCD 450 Cast Iron using Coated and Uncoated Irregular Milling Tools

    Science.gov (United States)

    Razlan Yusoff, Ahmad; Arsyad, Fitriyanti

    2016-02-01

    In this project, the effects of different cutting parameters on surface roughness and power consumption when machining FCD450 cast iron were studied using coated and uncoated irregular milling tool geometry of variable helix and pitch. Their responses on roughness and power consumption were evaluated based on the spindle speed, feed rate, and depth of cut, machining length and machining time. Results showed that except spindle speed and machining length, other parameters such as feed rate, axial and radial depth of cut and also machining time proportionate with surface roughness. The power consumption proportionately increase for all cutting parameters except feedrate. It is showed that the average decrement 27.92 percent for surface roughness and average decrement 9.32 percent for power consumption by using coated compared to uncoated tool. Optimum cutting parameters for both minimum surface roughness and power consumption can be determined. The coated tools performed better than uncoated milling tools for responses of surface roughness and power consumption to increase machining productivity and profit.

  13. Experimental Investigation of Erosive Wear on the High Chrome Cast Iron Impeller of Slurry Disposal Pump Using Response Surface Methodology

    Directory of Open Access Journals (Sweden)

    Sunil Kumar

    2012-05-01

    Full Text Available Erosive wear occurs on the impeller and volute casing of the slurry disposal pump due to the impact of the ash particles on the impeller with a high velocity. Due to erosive wear, pump life become very short. The service life of centrifugal pump, handling slurry can be increased by reducing the erosive wear. In the present work, the experimental investigation of erosive wear has been carried out on the high speed slurry erosion tester to understand the effects of the ash concentration in slurry, rotational speed of the pump impeller and ash particle size on erosive wear. The erosive wear behavior of high chrome cast iron was investigated by Response surface methodology (RSM. Analysis of variance (ANOVA was used for statistical analysis and the modeled values for the response were obtained with the help of modeled equation. The result shows that the ash concentration in slurry and kinetic energy of the moving particles highly contributes to erosive wear of pump impeller as compared to the ash particle size.

  14. EXPERIMENTAL INVESTIGATION OF EROSIVE WEAR ON THE HIGH CHROME CAST IRON IMPELLER OF SLURRY DISPOSAL PUMP USING RESPONSE SURFACE METHODOLOGY

    Directory of Open Access Journals (Sweden)

    Jasbir Singh Ratol

    2012-07-01

    Full Text Available Erosive wear occurs on the impeller and volute casing of the slurry disposal pump due to the impact of the ash particles on the impeller with a high velocity. Due to erosive wear, pump life become very short. The service life of centrifugal pump, handling slurry can be increased by reducing the erosive wear. In the present work, the experimental investigation of erosive wear has been carried out on the high speed slurry erosion tester to understand the effects of the ash concentration in slurry, rotational speed of the pump impeller and ash particle size on erosive wear. The erosive wear behaviour of high chrome cast iron was investigated by Response surface methodology (RSM. Analysis of variance (ANOVA was used for statistical analysis and the modeled values for the response were obtained with the help of modeled equation. The result shows that the ash concentration in slurry and kinetic energy of the moving particles highly contributes to erosive wear of pump impeller as compared to the ash particle size.

  15. Control of Carbides and Graphite in Cast Irons Type Alloy’s Microstructures for Hot Strip Mills

    Directory of Open Access Journals (Sweden)

    Sergio Villanueva Bravo

    2012-01-01

    Full Text Available The carbide and graphite formation and redistribution of alloy elements during solidification were investigated on high-speed steel (HS and Ni-hard type cast irons with Nb and V. The crystallization of hypereutectic HSS proceeds in the order of primary MC, γ + MC, γ + M6C, γ + M7C3, and γ +  graphite eutectic, in hypoeutectic alloys proceeds in the order of primary γ, γ + MC, γ + graphite, γ + M6C, and γ + M7C3 eutectic, and in Ni-hard proceeds in the order of primary γ, γ + MC, γ + M3C, and γ +  graphite eutectic. The γ +  graphite eutectic solidifies with the decrease of V, Nb, and Cr and the increase of Si and C contents in residual liquid during solidification. The behavior in graphite forming tendency in the residual liquid is estimated by the parameter ∑CLimi′. The eutectic graphite crystallizes at the solid fraction when ∑CLimi′ takes a minimum value. The amount of graphite increases with the decrease in ∑CLimi′ of initial alloy content in both specimens. Inoculation with ferrosilicon effectively increases the graphite content in both specimens.

  16. EFFECT OF TOOL NOSE RADIUS AND CUTTING PARAMETERS ON TOOL LIFE, SURFACE ROUGHNESS IN TURNING OF GREY CAST IRON

    Directory of Open Access Journals (Sweden)

    Prasanna P Kulkarni

    2014-03-01

    Full Text Available In metal cutting industries peoples are trying to reduce the cost of the production by proper selection of inserts, tool geometry, and cutting conditions to obtain economical benefits. Tool nose radius has significant influence on tool life and surface finish. The aim of this research is to investigate the effect of tool nose radius under different cutting conditions and their effect on tool life, surface roughness. The measurement has been carried out by rough boring operation using grey cast iron cylinder liners at three cutting speed (Vc and feed rate (f. Depth of cut (doc is kept constant at 2.5mm.Cutting tool used in this work is multilayer coated tool of nose radius 0.8mm and 1.2mm nose radius. Tool coated with titanium nitride (TiN + titanium carbo nitride (TiCN +Aluminium oxide (Al2O3 coating. The insert is designated with SNMG 120408. Cutting conditions used is speed (Vc 100m/min, 125m/min and 150m/min. Feed rate (f 0.20mm/rev,0.23mm/rev,0.27mm/rev.Finally results of the present work determine the appropriate parameter for increasing the tool life and surface finish for two different nose radius tools.

  17. The ancient Chinese casting techniques

    Directory of Open Access Journals (Sweden)

    Tan Derui

    2011-02-01

    Full Text Available In the course of Chinese civilization, which lasted more than 5,000 years, casting production has made a huge contribution. In this paper, some representative metal castings were presented. According to their forming techniques, they can be grouped into stone mould casting, clay mould casting, ablation casting, lost wax casting, stack casting, permanent mould casting, sand casting, etc. According to their materials, they can be categorized into tin bronze, bimetallic bronze, malleable cast iron, ductile cast iron, brass, cupronickel alloy (Packtong, etc. According to their surface decorative techniques they can be devided into gem inlay, gilding, gold and silver inlay, copper inlay, engraved decoration, surface tin-enrichment, mother-of-pearl inlay, burnished works with gold or silver inlay, surface coloring and cloisonné enamel, etc.

  18. Effect of Mn, Si, and Cooling Rate on the Formation of Iron-Rich Intermetallics in 206 Al-Cu Cast Alloys

    Science.gov (United States)

    Liu, K.; Cao, X.; Chen, X.-G.

    2012-10-01

    The solidification structures of commercial 206 Al-Cu cast alloys with 0.15 pct Fe have been studied using thermal analysis (TA), differential scanning calorimetry (DSC), scanning electron microscopy (SEM), and electron backscattered diffraction (EBSD). The EBSD results have shown that there are two iron-rich intermetallics: Chinese script α-Fe and platelet-like β-Fe. The addition of either Mn or Si has helped to promote the formation of α-Fe and hinder the precipitate of β-Fe. The combined addition of both Mn and Si is even more effective than the individual addition of either Mn or Si. The full solidification sequence of the 206 cast alloy has been established. The volume percent and formation temperature increase for α-Fe but decrease for β-Fe with increasing cooling rate. The platelet β-Fe can be effectively suppressed in 206 cast alloys by controlling the alloy chemistry and cooling rate. A casting process map is proposed to correlate the Mn and Si contents with cooling rates for the 206 cast alloys.

  19. Constrained/unconstrained solidification within the massive cast steel/iron ingots

    Directory of Open Access Journals (Sweden)

    W. S. Wołczyński

    2010-04-01

    Full Text Available Some properties of the ingot and especially of the steel forging ingots depend on the ratio of a columnar structure area to an equiaxed structure area created during solidification. The C-E transition is fundamental phenomenon that can be applied to characterize massive cast steel ingots produced by the casting house. The mentioned ratio is created spontaneously due to the rate of heat transfer towards the ceramic mould and then to the environment. The ceramic mould operates as an isolator. So that the thickness of the mould together with a growing solid fraction control the heat transfer and finally the ratio of the columnar structure area to the equiaxed structure area. At first the increase of heat accumulation within the ceramic mould is observed. Next the stationary state for heat transfer is created and finally a gentle abatement of the mould temperature associated with the heat output to the environment is expected. The steep thermal gradients correspond to the increase of heat accumulation in the ceramic mould. The steep thermal gradients are required to promote the columnar structure formation. The full heat accumulation in the mould corresponds well with the C-E transformation while the appearance of the moderate thermal gradients is referred to the gentle temperature abatement within the ceramic mould. The equiaxed structure is expected within this period of heat transfer behavior. The steep thermal gradients involve the activity of viscosity gradient in the liquid. As the result a sedimentary cones are formed at the bottom of the ingot. The C-E transformation is associated with competition between columnar and equaixed structure formation. At the end of competition a fully equiaxed structure is formed. The viscosity gradient is replaced by the thermophoresis which is the driving force for the deposition of some equiaxed grain layers onto the surface of C+E zone. The convection together with the gravity allow the layers to be uniform

  20. Effect of iron-intermetallics and porosity on tensile and impact properties of aluminum-silicon-copper and aluminum-silicon-magnesium cast alloys

    Science.gov (United States)

    Ma, Zheyuan

    Aluminum-silicon (Al-Si) alloys are an important class of materials that constitute the majority of aluminum cast parts produced, due to their superior properties and excellent casting characteristics. Within this family of alloys, Al-Si-Cu and Al-Si-Mg cast alloys are frequently employed in automotive applications. The commercially popular 319 and 356 alloys, representing these two alloy systems, were selected for study in the present work, with the aim of investigating the effect of iron intermetallics and porosity on the alloy performance. This was carried out through a study of the tensile and impact properties, these being two of the important mechanical properties used in design calculations. Iron, through the precipitation of second phase intermetallic constituents, in particular the platelike beta-Al5FeSi phase, is harmful to the alloy properties. Likewise, gas- or shrinkage porosity in castings is also detrimental to the mechanical properties. By determining the optimum alloying, melt processing and solidification parameters (viz., Fe content, Sr modification and cooling rate) required to minimize the harmful effects of porosity and iron intermetallics, and studying their role on the fracture behavior, the fracture mechanism in the alloys could be determined. Castings were prepared from both industrial and experimental 319.2, B319.2 and A356.2 alloy melts, containing Fe levels of 0.2--1.0 wt%. Sr-modified (˜200 ppm) melts were also prepared for each alloy Fe level. The end-chilled refractory mold used provided directional solidification and a range of cooling rates (or dendrite arm spacings, DAS) within the same casting. Tensile and impact test samples machined from specimen blanks sectioned from the castings at various heights above the chill end provided DASs of 23--85mum. All samples were T6-heat-treated before testing. Tests were carried out employing Instron Universal and Instrumented Charpy testing machines. Optical microscopy, image analysis, SEM

  1. Influence of New Sol-gel Refractory Coating on the Casting Properties of Cold Box and Furan Cores for Grey Cast iron

    DEFF Research Database (Denmark)

    Nwaogu, Ugochukwu Chibuzoh; Poulsen, T.; Bischoff, C;

    2010-01-01

    by measuring the heating curves. The viscosity of the coating, moisture content and the permeability of the cores were evaluated. The surface quality of the castings was investigated using SEM and OM. The results show that the moisture content of the cores affected the permeability. In furan cores the vapour...

  2. A fracture mechanics safety concept to assess the impact behavior of ductile cast iron containers for shipping and storage of radioactive materials

    International Nuclear Information System (INIS)

    Within the scope of the German licensing procedures for shipping and storage containers for radioactive materials made of ductile cast iron, BAM performs approval design tests including material tests to ensure the main safety goals of shielding, leaktightness and subcriticality under ''Type B accident conditions''. So far the safety assessment concept of BAM is based essentially on the experimental proof of container strength by prototype testing under most damaging test conditions in connection with complete approval design tests, and has been developed especially for cylindrical casks like CASTOR- and TN-design. In connection with the development of new container constructions such as ''cubic cast containers'', and the fast developments in the area of numerical calculation methods, there is a need for a more flexible safety concept especially considering fracture mechanics aspects.This paper presents the state of work at BAM for such an extended safety concept for ductile cast iron containers, based on a detailed brittle fracture safe design proof. The requirements on stress analysis (experimental or numerical), material properties, material qualification, quality assurance provisions and fracture mechanics safety assessment, including well defined and justified factors of safety, are described. ((orig.))

  3. Effects of HIP and forging on fracture behaviour in cast iron with spheroidal vanadium carbides dispersed within martensitic-matrix microstructure

    International Nuclear Information System (INIS)

    The cast iron with spheroidal vanadium carbides dispersed within martensitic-matrix microstructure was developed as a die material due to its high hardness. In order to achieve high performances of dies, not only the hardness but also the mechanical properties such as fracture toughness and fatigue crack propagation (FCP) resistance should be improved. In this paper, hot isostatic pressing (HIP) or forging was applied to the cast iron to improve mechanical properties, and the fracture behaviour, such as flexural strength, fracture toughness and FCP, was studied. The average flexural strength was reduced by forging because of the enhanced notch sensitivity due to the increase in the hardness. The fracture toughness was not affected by HIP nor forging while its scatter was significantly reduced by both post-treatments. The intrinsic FCP resistance taking account of crack closure was the same regardless of the application of HIP or forging, indicating that a slight change in the microstructure resulting from both treatments and the presence of casting defects exerted little influence on FCP behaviour. It could be concluded that both HIP and forging could improve the hardness of the material, while fracture toughness and FCP resistance were maintained.

  4. The role of iron in the formation of porosity in Al-Si-Cu-based casting alloys. Part 3: A microstructural model

    Energy Technology Data Exchange (ETDEWEB)

    Taylor, J.A.; Schaffer, G.B.; StJohn, D.H. [Univ. of Queensland, Brisbane, Queensland (Australia)

    1999-06-01

    Iron has been shown to have a significant effect on the formation of porosity and shrinkage defects in Al-Si-Cu-based foundry alloys. This is not simply a direct consequence of the physical presence of the {beta}-Al{sub 5}FeSi platelets in the microstructure, but is also due to the effect that these platelets have on the nucleation and growth of eutectic silicon. The alloy-dependent critical iron content determines when the {beta} phase first solidifies and, hence, when it can participate in the silicon nucleation event. At critical iron contents, the {beta} phase solidifies as the initial component of the ternary eutectic. However, at supercritical iron contents, the {beta} phase solidifies as the initial component of the ternary eutectic solidification begins, while, at subcritical iron contents, the {beta} phase forms as a component of the ternary eutectic only after the binary Al-Si eutectic is well established. Each of these paths of microstructural evolution leads to different variations in microstructural permeability and, hence, interdendritic feedability and porosity formation. The actual porosity-forming response to these alloy-induced microstructural changes is influenced by the solidification conditions in the casting.

  5. Ductile fracture evaluation of ductile cast iron and forged steel by nonlinear-fracture-mechanics. Pt. 1. Tensile test by large scaled test pieces with surface crack

    International Nuclear Information System (INIS)

    The ductile fracture tests of Ductile Cast Iron and Forged Steel under a tensile stress condition were conducted using large-scaled flat test specimens with a surface crack and were evaluated by the J-integral values, in order to propose an evaluation method of initiation of ductile fracture of a cask body with crack by nonlinear-fracture-mechanics. Following results were obtained. 1) 1 -strain relations of Ductile Cast Iron and Forged Steel under the tensile stress condition were obtained, which is necessary for the development of J-integral design curves for evaluating the initiation of ductile fracture of the cask body. 2) In case of Ductile Cast Iron, the experimental J-integral values obtained from strain-gauges showed a good agreement with the linear-elastic-theory by Raju and Newman at room temperature, in both elastic and plastic regions. But, at 70degC in plastic region, the experimental i-integral values showed middle values between those predicted by the linear-elastic-theory and by the non- linear-elastic- theory (based on the fully plastic solution by Yagawa et al.). 3) In case of Forged Steel at both -25degC and room temperature, the experimental i-integral values obtained from strain-gauges showed a good agreement with those predicted by the linear-elastic-theory by Raju and Newman, in the elastic region. In the plastic region, however, the experimental i-integral values fell apart from the curve predicted by the linear-elastic-theory by Raju and Newman, and also approached to those by the non-linear-elastic-theory with increasing strain.(author)

  6. Effects of W on microstructure of as-cast 28 wt.%Cr–2.6 wt.%C–(0–10)wt.%W irons

    International Nuclear Information System (INIS)

    Microstructures of as-cast 28 wt.%Cr–2.6 wt.%C irons containing (0–10)wt.%W with the Cr/C ratio about 10 were studied and related to their hardness. The experimental irons were cast into dry sand molds. Microstructural investigation was performed by light microscopy, X-ray diffractometry, scanning electron microscopy, transmission electron microscopy and energy-dispersive X-ray spectrometry. It was found that the irons with 1 to 10 wt.%W addition was hypereutectic containing large primary M7C3, whereas the reference iron without W addition was hypoeutectic. The matrix in all irons was austenite, partly transformed to martensite during cooling. The volume fractions of primary M7C3 and the total carbides increased, but that of eutectic carbides decreased with increasing the W content of the irons. W addition promoted the formation of W-rich M7C3, M6C and M23C6. At about 4 wt.%W, two eutectic carbides including M7C3 and M6C were observed together with primary M7C3. At 10 wt.%W, multiple carbides including primary M7C3, fish-bone M23C6, and M6C were observed. MxC where x = 3 or less has not been found due possibly to the high M/C ratio in the studied irons. W distribution to all carbides has been determined increasing from ca. 0.3 to 0.8 in mass fraction as the W content in the irons was increased. W addition led to an increase in Vickers macro-hardness of the irons up to 671 kgf/(mm)2 (HV30/15) obtained from the iron with 10 wt.%W. The formation of primary M7C3 and aggregates of M6C and M23C6 were the main reasons for hardness increase, indicating potentially improved wear performance of the as-cast irons with W addition. - Highlights: • W addition at 1 up to 10 wt.%W to Fe–28Cr–2.6C produced “hypereutectic” structure. • W addition promoted the formation of W-rich M7C3, M6C and M23C6. • M23C6 has higher Fe/Cr and W/Cr atm% ratios than those in M7C3. • Si content and high W content over about 11 atm% are characteristics of M6C. • Primary M7C3 and

  7. Effects of W on microstructure of as-cast 28 wt.%Cr–2.6 wt.%C–(0–10)wt.%W irons

    Energy Technology Data Exchange (ETDEWEB)

    Imurai, S. [Department of Physics and Materials Science, Chiang Mai University, Chiang Mai 50200 (Thailand); Thanachayanont, C.; Pearce, J.T.H. [National Metal and Materials Technology Center, Pathumthani 12120 (Thailand); Tsuda, K. [Institute of Multidisciplinary Research for Advanced Materials, Tohoku University, Sendai 980-8577 (Japan); Chairuangsri, T., E-mail: tchairuangsri@gmail.com [Department of Industrial Chemistry, Chiang Mai University, Chiang Mai 50200 (Thailand)

    2015-01-15

    Microstructures of as-cast 28 wt.%Cr–2.6 wt.%C irons containing (0–10)wt.%W with the Cr/C ratio about 10 were studied and related to their hardness. The experimental irons were cast into dry sand molds. Microstructural investigation was performed by light microscopy, X-ray diffractometry, scanning electron microscopy, transmission electron microscopy and energy-dispersive X-ray spectrometry. It was found that the irons with 1 to 10 wt.%W addition was hypereutectic containing large primary M{sub 7}C{sub 3}, whereas the reference iron without W addition was hypoeutectic. The matrix in all irons was austenite, partly transformed to martensite during cooling. The volume fractions of primary M{sub 7}C{sub 3} and the total carbides increased, but that of eutectic carbides decreased with increasing the W content of the irons. W addition promoted the formation of W-rich M{sub 7}C{sub 3}, M{sub 6}C and M{sub 23}C{sub 6}. At about 4 wt.%W, two eutectic carbides including M{sub 7}C{sub 3} and M{sub 6}C were observed together with primary M{sub 7}C{sub 3}. At 10 wt.%W, multiple carbides including primary M{sub 7}C{sub 3}, fish-bone M{sub 23}C{sub 6}, and M{sub 6}C were observed. M{sub x}C where x = 3 or less has not been found due possibly to the high M/C ratio in the studied irons. W distribution to all carbides has been determined increasing from ca. 0.3 to 0.8 in mass fraction as the W content in the irons was increased. W addition led to an increase in Vickers macro-hardness of the irons up to 671 kgf/(mm){sup 2} (HV30/15) obtained from the iron with 10 wt.%W. The formation of primary M{sub 7}C{sub 3} and aggregates of M{sub 6}C and M{sub 23}C{sub 6} were the main reasons for hardness increase, indicating potentially improved wear performance of the as-cast irons with W addition. - Highlights: • W addition at 1 up to 10 wt.%W to Fe–28Cr–2.6C produced “hypereutectic” structure. • W addition promoted the formation of W-rich M{sub 7}C{sub 3}, M{sub 6}C and M

  8. Assessment of the influence of magnesium content on the shape and amount of graphite precipitation in spheroidal cast iron manufactured by Metal-Odlew s.c.

    Directory of Open Access Journals (Sweden)

    W. Orłowicz

    2009-01-01

    Full Text Available The study presents the influence of time on cast iron spheroidisation, modification of the magnesium content in the alloy, and the influence of the magnesium content on the shape and number of graphite precipitations. For one particular set of production conditions, it was observed that 17 minutes after completing the modification and spheroidisation procedure, the magnesium content had decreased from 0.070% to 0.040%. This resulted in a decrease in the graphite precipitation shape index Ss from 0.081 to 0.067, as well as a decrease in the average number of graphite precipitations NA from 568 mm-2 to 305 mm-2.

  9. Iron

    Science.gov (United States)

    Iron is a mineral that our bodies need for many functions. For example, iron is part of hemoglobin, a protein which carries ... It helps our muscles store and use oxygen. Iron is also part of many other proteins and ...

  10. Cast iron promises.

    Science.gov (United States)

    Hawker, Andrew

    2007-01-01

    During the Victorian era, a fiercely competitive industry emerged to build and operate Britain's railways. Many of the design and construction skills required were still fairly rudimentary, and were typically developed through practical experience. The resulting mix of entrepreneurship and new technology reshaped the landscape, but often in ways which proved hazardous for passengers. Minor accidents were commonplace, and a number of major failures occurred, one such being the collapse of the Tay Bridge, in 1879. Events in the ten years prior to this disaster still have some resonance today. Ambitions to exploit new technology are not always matched by foresight in the planning, financing or management of projects. Contracts may be based on wrong assumptions, and prove difficult to enforce. Once a project has gathered momentum, those working on it may fear that any attempt to draw attention to risks or defects will be seen as disloyal. When work is completed, it cannot be assumed that formal inspections will reveal potential flaws, or that those using the technology will appreciate the need to follow the procedures laid down for them. Some possible parallels with recent experiences in NHS computing are noted. PMID:18005560

  11. Cast iron promises

    Directory of Open Access Journals (Sweden)

    Andrew Hawker

    2007-09-01

    Events in the ten years prior to this disaster still have some resonance today. Ambitions to exploit new technology are not always matched by foresight in the planning, financing or management of projects. Contracts may be based on wrong assumptions, and prove difficult to enforce. Once a project has gathered momentum, those working on it may fear that any attempt to draw attention to risks or defects will be seen as disloyal. When work is completed, it cannot be assumed that formal inspections will reveal potential flaws, or that those using the technology will appreciate the need to follow the procedures laid down for them. Some possible parallels with recent experiences in NHS computing are noted.

  12. Thermal Test and Numerical Simulation of Nodular Cast Iron Cooling Stave%球墨铸铁冷却壁热态实验与数值模拟

    Institute of Scientific and Technical Information of China (English)

    洪军; 左海滨; 张建良; 李峰光; 沈猛; 铁金艳

    2014-01-01

    为测定消失模工艺生产的球墨铸铁冷却壁的实际冷却性能,进行1∶1热态实验.同时建立铸铁冷却壁三维稳态传热模型,模拟铸铁冷却壁的温度场分布.热态实验结果表明:该球墨铸铁冷却壁壁体与冷却水之间的综合换热系数为228W/(m2·℃),与日本新日铁第四代冷却壁相近.炉温变化对冷却壁热面温度的影响大于其对冷却壁冷面温度的影响.提高冷却水速可以降低冷却壁壁体温度,但效果不明显.模型计算结果与热态实验的比较,验证了计算模型的有效性.%To determine the actual performance of nodular cast iron stave produced by lost foam casting,the 1∶1 thermal test was carried out.The 3D steady-state heat transfer model was established to calculate the temperature field of cast iron cooling stave.Thermal test results show that the cast iron cooling stave has good cooling ability,the integrated heat transfer coefficient is 228 W/ (m2· ℃),which is close to Nippon Steel fourth-generation stave.Effect of furnace gas temperature on hot face temperature is greater than effect on cold face temperature.Increasing of cooling water velocity can lower hot face temperature,but the effect is not obvious.The comparison between computational model and thermal test verified the validity of the computational model.

  13. Physico-chemical properties of quartz from industrial manufacturing and its cytotoxic effects on alveolar macrophages: The case of green sand mould casting for iron production.

    Science.gov (United States)

    Di Benedetto, Francesco; Gazzano, Elena; Tomatis, Maura; Turci, Francesco; Pardi, Luca A; Bronco, Simona; Fornaciai, Gabriele; Innocenti, Massimo; Montegrossi, Giordano; Muniz Miranda, Maurizio; Zoleo, Alfonso; Capacci, Fabio; Fubini, Bice; Ghigo, Dario; Romanelli, Maurizio

    2016-07-15

    Industrial processing of materials containing quartz induces physico-chemical modifications that contribute to the variability of quartz hazard in different plants. Here, modifications affecting a quartz-rich sand during cast iron production, have been investigated. Composition, morphology, presence of radicals associated to quartz and reactivity in free radical generation were studied on a raw sand and on a dust recovered after mould dismantling. Additionally, cytotoxicity of the processed dust and ROS and NO generation were evaluated on MH-S macrophages. Particle morphology and size were marginally affected by casting processing, which caused only a slight increase of the amount of respirable fraction. The raw sand was able to catalyze OH and CO2(-) generation in cell-free test, even if in a lesser extent than the reference quartz (Min-U-Sil), and shows hAl radicals, conventionally found in any quartz-bearing raw materials. Enrichment in iron and extensive coverage with amorphous carbon were observed during processing. They likely contributed, respectively, to increasing the ability of processed dust to release CO2- and to suppressing OH generation respect to the raw sand. Carbon coverage and repeated thermal treatments during industrial processing also caused annealing of radiogenic hAl defects. Finally, no cellular responses were observed with the respirable fraction of the processed powder. PMID:27015375

  14. Continuous cooling transformation behavior for heat treatment of spheroidal graphite cast iron. Kyujo kokuen chutetsu no netsushoriji ni okeru renzoku reikyaku hentai kyodo

    Energy Technology Data Exchange (ETDEWEB)

    Nakata, T.; Matsumoto, H. (Shibaura Institute of Technology, Tokyo (Japan)); Kasugai, T. (National Research Institute for Metals, Tsukuba (Japan)); Koyama, M. (Automobile Foundry Co. Ltd., Yokohama (Japan))

    1992-08-25

    In order to study basic heat treatment properties of spheroidal graphite cast iron, the continuous cooling transformation(CCT) diagrams for the material equivallent to FCD700 under various austenitized conditions were obtained. There were 4 kinds of austenitized conditions varying from 1123K and 420s to 1323K and 1,800s. Eight kinds of cooling time from the austenitized temperature to 773K ranged from 6s to 4,000s. The transformation temperature was measured by a thermal expansion method. When the austenitized temperature was increased from 1123K to 1323K, ferrite and pearlite transformation regions moved a little in the CCT diagrams and the martensite transformation temperature decreased from 493K to 458K. The bainite region in the CCT diagrams disappeared at the austenite temperatures above 1223K. The nucleation sites of ferrite and pearlite in the spheroidal graphite cast iron were generated at grain boundary between austenite and graphite but not at grain boundary between austenites. The reason of such phenomena was also studied. 10 refs., 8 figs., 2 tabs.

  15. Kinetics of the formation of Fe2B layers in gray cast iron: Effects of boron concentration and boride incubation time

    International Nuclear Information System (INIS)

    The growth kinetics of Fe2B layers formed at the surface of gray cast iron were evaluated in this study. The pack-boriding process was applied to produce the Fe2B phase at the material surface, and the variables included three temperatures (1173, 1223 and 1273 K) and four exposure times (2, 4, 6 and 8 h). Taking into account the growth fronts obtained at the surface of the material and the mass balance equation at the Fe2B/substrate interface, the boron diffusion coefficient on the borided phase was estimated for the range of treatment temperatures. Likewise the parabolic growth constant, the instantaneous velocity of the Fe2B/substrate interface, and the weight gain in the borided samples were established as a function of the parameters τ(t) and α(C), which are related to the boride incubation time (t0(T)) and boron concentration at the Fe2B phase, respectively. Observation of the growth kinetics of the Fe2B layers in gray cast irons suggest an optimum value of boron concentration that is in good agreement with the set of boriding experimental conditions used in this work.

  16. The Structure and Bond Strength of Composite Carbide Coatings (WC-Co + Ni) Deposited on Ductile Cast Iron by Thermal Spraying

    Science.gov (United States)

    Ksiazek, Marzanna; Boron, Lukasz; Radecka, Marta; Richert, Maria; Tchorz, Adam

    2016-02-01

    An investigation was conducted to determine the role of Ni particles in the WC-Co coating produced with the supersonic method on microstructure, mechanical, and wear properties in a system of type: WC-Co coating/ductile cast iron. The microstructure of the thermal-sprayed WC-Co + Ni coating was characterized by scanning electron and transmission electron microscopes as well as the analysis of chemical and phase composition in microareas (EDS, XRD). The microstructure of the WC-Co + Ni coating consisted of large, partially molten Ni particles and very fine grains of WC embedded in cobalt matrix, coming to the size of nanocrystalline. Moreover, the results were discussed in reference to examination of bending strength considering cracking and delamination in the system of (WC-Co + Ni)/ductile cast iron as well as hardness and wear resistance of the coating. It was found that the addition of Ni particles was significantly increase resistance to cracking and wear behavior in the studied system.

  17. 从铸铁件质量所想到的熔炼技术%Melting Technique Associated with Quality of Iron Castings

    Institute of Scientific and Technical Information of China (English)

    钱立; 王峰

    2011-01-01

    由几个具体生产实例指出获得优质铸件的铁液要求为:足够高的温度、准确而稳定的化学成分、气体和非金属夹杂物少,等.介绍了提高冲天炉熔炼温度的重要性以及350~550℃热风、2%~4%富氧率送风、冷风优质焦三项提高铁液温度的技术.同时,介绍了感应炉熔炼中平衡温度、沸腾温度、临界温度及过热温度的概念和控制原则,以及冲天炉风口喷吹固体粉料的技术.总结认为:铸铁熔炼中温度虽是核心问题,但不是全部;如果要从根本上提高铸铁件质量,须从“人”抓起.%Based on several productive examples, requirements for the iron melt to obtain high quality castings were proposed such as enough high temperature, accurate and stable chemical composition, less gas and nonmetal debris, etc. Three techniques to increase iron melt temperature were introduce) including the usage of hot blast with temperature of 350~550 ℃, 2%~4% oxygen-richen blast, cold blast plus high quality coke. At the same time, the definitions and control principles of the induction furnace melting -related equilibrious temperature, boiling temperature, critical temperature and superheating temperature was described, and the technique of injecting solid powder materials through the tuyeres of cupola was also introduced. By the end, it was pointed out that although temperature is the key problem of cast iron melting, it isn't the all, and the work to thoroughly improve the iron castings quality should be started from the improvement of the personnel intrinsic qualification.

  18. Theoretical basis of Al-Si coat crystallization on gray and nodular cast iron and making the layered items using it

    Directory of Open Access Journals (Sweden)

    S. Pietrowski

    2011-12-01

    Full Text Available Purpose: The aim of this study was to present studies of crystallization and the construction of the coat consisting of Al-Si alloys, also with alloy additives: Ni, Cu and Mg, deposited on gray and nodular cast iron, and the connection through this coat the layered item. On this basis, a model of creating a coat and layered item was developed.Design/methodology/approach: Studies of coats and layered products were carried out on scanning electron and optical microscopes. The chemical microanalysis and diffraction of backward scattered atoms in the characteristic areas of the coat and substrate material was made.Findings: : In this paper the influence of the most important technological factors on the thickness and phase construction of the silumin coat and connection quality in the layered item was presented.Research limitations/implications: Currently, research of dip application of coats made of silumins containing: Cu, Ni, Mg, Cr, Mo, W and V on non-alloy and alloy steels and the manufacture of layered items to their use are conducted.Practical implications: Dip coats are used as protective coats or intermediate coat of layered item. The paper presents an example of the implementation for the manufacture of the layered items low-alloyed gray cast iron-silumin coat-silumin reciprocating compressor body for room air conditioning.Originality/value: Originality of the paper consists in elaborating of the theoretical model of forming the diffusion layer made of Al-Si-M silumin on iron alloys. Theoretical basis of layers production were elaborated too. They are significant for collar fillings production in high-pressure combustion engines pistons, as anticorrosive layers and for layered items production.

  19. Iron

    Science.gov (United States)

    ... seafood, and foods that contain vitamin C , like citrus fruits, strawberries, sweet peppers, tomatoes, and broccoli. What ... diets. What are some effects of iron on health? Scientists are studying iron to understand how it ...

  20. Iron

    DEFF Research Database (Denmark)

    Hansen, Jakob Bondo; Moen, I W; Mandrup-Poulsen, T

    2014-01-01

    The interest in the role of ferrous iron in diabetes pathophysiology has been revived by recent evidence of iron as an important determinant of pancreatic islet inflammation and as a biomarker of diabetes risk and mortality. The iron metabolism in the β-cell is complex. Excess free iron is toxic......, but at the same time, iron is required for normal β-cell function and thereby glucose homeostasis. In the pathogenesis of diabetes, iron generates reactive oxygen species (ROS) by participating in the Fenton chemistry, which can induce oxidative damage and apoptosis. The aim of this review is to...... present and discuss recent evidence, suggesting that iron is a key pathogenic factor in both type 1 and type 2 diabetes with a focus on inflammatory pathways. Pro-inflammatory cytokine-induced β-cell death is not fully understood, but may include iron-induced ROS formation resulting in dedifferentiation...