WorldWideScience

Sample records for aluminium additions

  1. Aluminium content of some foods and food products in the USA, with aluminium food additives.

    Science.gov (United States)

    Saiyed, Salim M; Yokel, Robert A

    2005-03-01

    The primary objective was to determine the aluminium (Al) content of selected foods and food products in the USA which contain Al as an approved food additive. Intake of Al from the labeled serving size of each food product was calculated. The samples were acid or base digested and analysed for Al using electrothermal atomic absorption spectrometry. Quality control (QC) samples, with matrices matching the samples, were generated and used to verify the Al determinations. Food product Al content ranged from Cheese in a serving of frozen pizzas had up to 14 mg of Al, from basic sodium aluminium phosphate; whereas the same amount of cheese in a ready-to-eat restaurant pizza provided 0.03-0.09 mg. Many single serving packets of non-dairy creamer had approximately 50-600 mg Al kg(-1) as sodium aluminosilicate, providing up to 1.5 mg Al per serving. Many single serving packets of salt also had sodium aluminosilicate as an additive, but the Al content was less than in single-serving non-dairy creamer packets. Acidic sodium aluminium phosphate was present in many food products, pancakes and waffles. Baking powder, some pancake/waffle mixes and frozen products, and ready-to-eat pancakes provided the most Al of the foods tested; up to 180 mg/serving. Many products provide a significant amount of Al compared to the typical intake of 3-12 mg/day reported from dietary Al studies conducted in many countries. PMID:16019791

  2. Aluminium content of foods originating from aluminium-containing food additives.

    Science.gov (United States)

    Ogimoto, Mami; Suzuki, Kumi; Haneishi, Nahoko; Kikuchi, Yuu; Takanashi, Mayu; Tomioka, Naoko; Uematsu, Yoko; Monma, Kimio

    2016-09-01

    Aluminium (Al) levels of 90 food samples were investigated. Nineteen samples contained Al levels exceeding the tolerable weekly intake (TWI) for young children [body weight (bw): 16 kg] when consuming two servings/week. These samples were purchased multiple times at specific intervals and were evaluated for Al levels. Al was detected in 27 of the 90 samples at levels ranging from 0.01 (limit of quantitation) to 1.06 mg/g. Of these, the Al intake levels in two samples (cookie and scone mix, 1.3 and 2 mg/kg bw/week, respectively) exceeded the TWI as established by European Food Safety Authority, although the level in the scone mix was equivalent to the provisional TWI (PTWI) as established by Joint Food and Agriculture Organization of the United Nations/World Health Organization Expert Committee on Food Additives. The Al levels markedly decreased in 14 of the 19 samples with initially high Al levels. These results indicated reductions in the Al levels to below the PTWI limits in all but two previously identified food samples. PMID:27092423

  3. Additive manufacture of an aluminium alloy: processing, microstructure, and mechanical properties

    OpenAIRE

    Aboulkhair, Nesma T.

    2016-01-01

    Additive manufacturing of aluminium alloys using selective laser melting (SLM) is of research interest nowadays because of its potential benefits in industry sectors such as aerospace and automotive. However, in order to demonstrate the credibility of aluminium SLM for industrial needs, a comprehensive understanding of the interrelation between the process parameters, produced microstructure, and mechanical behaviour is still needed. This thesis aims at contributing to developing this compreh...

  4. Additive layer manufactured sinter-style aluminium/ammonia heat pipes

    OpenAIRE

    Masoud Ameli, Seied

    2012-01-01

    A novel heat pipe (HP) manufacturing method has been developed based on an additive layer manufacturing technique called “selective laser melting” or SLM. This innovation is expected to benefit current applications of aluminium/ammonia heat pipes in space and terrestrial projects as well as many new HP applications. The project was jointly sponsored by the Northumbria University and Thermacore, a world leading heat pipe manufacturing company in the UK, and formed the feasibility stage of ...

  5. The crystallisation of the aluminium bronze with additions of Si, Cr, Mo and/or W

    Directory of Open Access Journals (Sweden)

    B.P. Pisarek

    2007-08-01

    Full Text Available Purpose: The aim of this paper is description of the process of the crystallization of new aluminium bronzes with the complex silicides of the iron.Design/methodology/approach: Additions Cr, W, Mo and Si were introduced to create in the microstructure of the aluminium bronze of the complex silicides of the iron about high mechanical and physical proprieties to the bronze BA1044. The process of formation the microstructure of the bronze with use of the method of the thermal and derivative analysis (TDA was analysed. The examinations under the microscope and X-ray microanalysis of the surface distribution of elements were conducted.Findings: From carried research results, that in the aluminium bronze BA1044 after addition Si, Cr, Mo and/or W the phase κFe, κNi crystallize as the complex silicides of the iron. Elements such as: Fe and Si dissolve first of all in silicides in the smaller stage in the matrix of the bronze, Mn and Ni they dissolve in matrix and silicides, Cr dissolves in the larger stage in silicides than in the matrix, W and Mo dissolve in silicides however they crystallize as nanocrystals in the metal matrix and create with her composite.Research limitations/implications: Results of investigations of aluminium bronze BA1044 and alloys after adding to him about 1% Si were introduced in the article and suitably: 1.22 % Cr; 0.82 % Mo; 0.020 % W; 0.60 % Cr, 0.17 % Mo and 0.017 % W.Originality/value: The original results of the investigations of the crystallization of the new bronzes (innovative materials and casting technologies for which the process of arising microstructure the method TDA was not analysed so far were introduced in the article. The article possesses cognitive values not only essential for researcher but and practician-melters.

  6. The influence of various solute additions on the process of vacancy clustering in aluminium

    International Nuclear Information System (INIS)

    This thesis deals with thin foils of binary aluminium-based alloys containing various amounts of magnesium, silver, germanium, silicon and zinc in solid solution, prepared from quenced bulk specimens. The influence of the various solute additions on the process of vacancy clustering in aluminium has been investigated, primarily with the aid of the transmission electron microscope. In the first chapter the purpose of the project is explained and placed in proper perspective. A brief introduction to transmission electron microscopy is presented in the second chapter. The third and fourth chapters comprise a literature survey to summarize the present state of development of the field of vacancy clustering covered by this disseration, including an introduction to some basic concepts needed for a full appreciation of the results. The following chapter describes the experimental procedure, where a detailed description is presented of concepts such as annealing and minimum annealing time, specimen preparation, quenching rate measurement, thickness measurement of the foil, and the calculation methods for the vacancy concentration and vacancy-solute binding energy. The results and discussion are presented in chapter six, where three main aspects of the vacancy cluster observed in this study examined, viz. (1) Classification of the various vacancy cluster observed according to their incidence and structural relationship. (2) Measurements are made of the vacancy concentration and of the binding energies between vancancies and solute atoms in aluminium-based alloys. (3) Finally, the experimentally observed size distribution of vacancy clusters in the various alloys are presented

  7. Microstructures and Properties of Aluminium-Magnesium Alloys with Additions of Manganese, Zirconium and Scandium

    OpenAIRE

    Johansen, Arve

    2000-01-01

    The present work reports on the effect of Mn-, Zr- and Sc-additions upon hot deformation properties, recrystallization properties and mechanical properties for different temper conditions of Al-Mg alloys.It can be stated that the addition of Mn, Zr and Sc improves the recrystallization properties and the mechanical properties of Al-Mg alloys. It should be emphasised that the precipitation of the metastable cubic Al3Zr and the stable cubic Al3(Sc,Zr) is favourable in an aluminium-magnesium mat...

  8. APPLICATION OF LASER ADDITIVE MANUFACTURING TO PRODUCE DIES FOR ALUMINIUM HIGH PRESSURE DIE-CASTING#

    Directory of Open Access Journals (Sweden)

    M.F.V.T. Pereira

    2012-01-01

    Full Text Available

    ENGLISH ABSTRACT: A number of laser additive manufacturing (LAM technologies can produce fully-dense metal components that potentially offer opportunities to apply the technology in die or mould making (known as rapid tooling. From these LAM technologies, three were selected for evaluation of their suitability as die cavity inserts in the manufacture of high pressure die-casting (HPDC dies. Apart from comparing the different LAM inserts with one another, their performance was also compared with components manufactured in a standard hot work steel. In the HPDC process, the die is unique to each component to be produced. Die cavities in particular are subjected to demanding conditions, such as cyclic heating caused by the introduction of molten aluminium at over 650°C, followed by cooling in water-based die release medium at temperatures around 25°C. Besides cyclic heating, the die cavities are also exposed to pressures exceeding 1500 MPa during the injection of molten aluminium into the cavities. This application of LAM, therefore, poses extreme challenges to the technology. The results of this study confirmed that the metals used in some of the LAM technologies did indeed meet the demanding requirements of the current application, and can lead to significant time- and cost-saving during product or process developments. Based on these findings, a number of recommendations are made for users interested in the application of LAM to produce die cavities.

    AFRIKAANSE OPSOMMING: ’n Aantal laser laagvervaardigingstegnologieë (LLV tegnolgieë is in staat om volledig digte metaalkomponente te lewer, wat tot gevolg het dat hierdie tegnologie potensieel vir vormingsmatrys- of gietmatrysvervaardiging gebruik kan word (bekend as snelgereedskap. Drie van hierdie LLV tegnologieë is gekies vir evaluasie van hulle geskiktheid as gietvorminsetsels tydens die vervaardiging van gietmatryse vir hoë druk matrysgiet (HDMG. Benewens die onderlinge

  9. Characterization of semi-solid processing of aluminium alloy 7075 with Sc and Zr additions

    Energy Technology Data Exchange (ETDEWEB)

    Rogal, Ł., E-mail: l.rogal@imim.pl [Institute of Metallurgy and Materials Science of the Polish Academy of Sciences, 25 Reymonta St., 30-059 Krakow (Poland); Dutkiewicz, J. [Institute of Metallurgy and Materials Science of the Polish Academy of Sciences, 25 Reymonta St., 30-059 Krakow (Poland); Atkinson, H.V. [The University of Leicester, Department of Engineering University Road, Leicester, LE1 7RH (United Kingdom); Lityńska-Dobrzyńska, L.; Czeppe, T. [Institute of Metallurgy and Materials Science of the Polish Academy of Sciences, 25 Reymonta St., 30-059 Krakow (Poland); Modigell, M. [RWTH Aachen—Department of Mechanical Process Engineering, 55 Templergraben St., Aachen (Germany)

    2013-09-15

    For thixoforming (semi-solid processing) it is necessary to have a fine globular microstructure in a semi-solid range. Here this has been obtained for 7075 aluminium alloy by addition of modifying agents: 0.5 weight % of scandium and zirconium. The thixoforming process was carried out at 632 °C which gave about 23 volume % of liquid phase. The microstructure of the thixo-formed part (a rotor) consisted of globular grains surrounded by precipitates of secondary phase. The average hardness of thixo-formed parts was 105 HV{sub 5} and the tensile strength 300 MPa. T6 heat treatments were performed with solutionisation at 450 °C for 30 min and 10 h. In both cases the ageing time was set as 18 h at 120 °C. The heat treatments led to an increase in average tensile strength up to 495 MPa. Transmission Electron Microscopy (TEM) analysis enabled the identification of precipitates of the metastable dispersoids of L1{sub 2}–Al{sub 3} (Zr, Sc) and η′ (MgZn{sub 2}) phases in the alloy after the thixoforming and T6 treatment. The measurements of rheological properties of 7075Al alloy with Sc and Zr additions in the semi-solid range indicated an increase of particle size and spheroidization leading to an observable decrease of viscosity during isothermal shearing. A shear rate jump experiment showed that with increasing shear rate the viscosity rapidly falls.

  10. B2-ordered iron-aluminium alloys strengthening. Influence of additions (Ni and B) and microstructure

    International Nuclear Information System (INIS)

    We study the effects of additions (Ni and B) and microstructure on the mechanical behaviour of 40 at. % Al iron-aluminium alloys. From a macroscopic point of view, we show that nickel reinforces FeAl alloys over the whole temperature range, but that it simultaneously leads to emphasize the room temperature brittleness of these alloys through a cleavage stress decrease. We confirm powder metallurgy grain refining interest to enhance yield stress as well as fracture resistance. We show that nickel-induced yield stress effect is additive to 'Hall-Petch' one. Also, we point out that the strengthening phenomena (nickel or grain size) cause the yield stress anomaly, which these alloys usually present, to be hidden. Through a dislocation structures analysis of deformed materials we precise that low temperature nickel-induced solid solution hardening (SSH) cannot be explained on the basis of classical SSH theories but more probably through nickel influence upon the Peierls stress. Moreover, we show that the APB tubes dragging model may be compatible with our microscopic and macroscopic results about the anomaly. Eventually, we put into relation a dynamic super-dislocations multiplication process observation (in situ transmission microscopy) with the nickel-containing alloys tendency to cleavage. (author)

  11. Effect of mechanical alloying and Ti addition on solution and ageing treatment of an AA7050 aluminium alloy

    OpenAIRE

    Kátia Regina Cardoso; Dilermando Nagle Travessa; Asunción García Escorial; Marcela Lieblich

    2007-01-01

    In this work, solution heat treatments at different temperatures were performed in a commercial based AA7050 aluminium alloy, with and without titanium addition, produced by mechanical alloying and hot extrusion with the aim to investigate the effect of titanium addition and mechanical alloying in the precipitates stability. The same heat treatment conditions were used in a reference sample obtained from a commercial AA7050 alloy. Solution heat treated samples were characterised by differenti...

  12. Aluminium Alloy AA6060 surface treatment with high temperature steam containing chemical additives

    DEFF Research Database (Denmark)

    Din, Rameez Ud; Tabrizian, Naja; Jellesen, Morten S.;

    2015-01-01

    The steam treatment process was employed to produce a conversion coating on aluminium alloy AA6060. The changes in microstructure and its effect on corrosion resistance properties were investigated. Various concentrations of KMnO4 containing Ce(NO3)3 was injected into the steam and its effect on...... the formation of steam-based conversion coating was evaluated. The use of Mn-Ce into the steam resulted in incorporation of these species into the conversion coating, which resulted in improved corrosion resistance of the alloy substrate....

  13. Structure and selected properties of high-aluminium Zn alloy with silicon addition

    OpenAIRE

    A. Zyska; Z. Konopka; M. Łągiewka; M. Nadolski

    2011-01-01

    The results of examinations concerning the abrasive wear resistance, hardness, and thermal expansion of high-aluminium zinc alloys are presented. The examinations were carried out for five synthetic ZnAl28 alloys with variable silicon content ranging from 0.5% to 3.5%, and – for the purpose of comparison – for the standardised ZnAl28Cu4 alloy. It was found that silicon efficiently increases the tribological properties and decreases the coefficient of thermal expansion of zinc alloys. The most...

  14. Gypsum addition to soils contaminated by red mud: implications for aluminium, arsenic, molybdenum and vanadium solubility.

    Science.gov (United States)

    Lehoux, Alizée P; Lockwood, Cindy L; Mayes, William M; Stewart, Douglas I; Mortimer, Robert J G; Gruiz, Katalin; Burke, Ian T

    2013-10-01

    Red mud is highly alkaline (pH 13), saline and can contain elevated concentrations of several potentially toxic elements (e.g. Al, As, Mo and V). Release of up to 1 million m(3) of bauxite residue (red mud) suspension from the Ajka repository, western Hungary, caused large-scale contamination of downstream rivers and floodplains. There is now concern about the potential leaching of toxic metal(loid)s from the red mud as some have enhanced solubility at high pH. This study investigated the impact of red mud addition to three different Hungarian soils with respect to trace element solubility and soil geochemistry. The effectiveness of gypsum amendment for the rehabilitation of red mud-contaminated soils was also examined. Red mud addition to soils caused a pH increase, proportional to red mud addition, of up to 4 pH units (e.g. pH 7 → 11). Increasing red mud addition also led to significant increases in salinity, dissolved organic carbon and aqueous trace element concentrations. However, the response was highly soil specific and one of the soils tested buffered pH to around pH 8.5 even with the highest red mud loading tested (33 % w/w); experiments using this soil also had much lower aqueous Al, As and V concentrations. Gypsum addition to soil/red mud mixtures, even at relatively low concentrations (1 % w/w), was sufficient to buffer experimental pH to 7.5-8.5. This effect was attributed to the reaction of Ca(2+) supplied by the gypsum with OH(-) and carbonate from the red mud to precipitate calcite. The lowered pH enhanced trace element sorption and largely inhibited the release of Al, As and V. Mo concentrations, however, were largely unaffected by gypsum induced pH buffering due to the greater solubility of Mo (as molybdate) at circumneutral pH. Gypsum addition also leads to significantly higher porewater salinities, and column experiments demonstrated that this increase in total dissolved solids persisted even after 25 pore volume replacements. Gypsum

  15. Study of silicon nitride sintering with additions of lanthanum, gadolinium and aluminium oxides

    International Nuclear Information System (INIS)

    Rare earth oxides have been employed as sintering aids of silicon nitride in order to form high dense materials with refractory phases at grain boundary. In this work, various compositions with lanthanum, gadolinium and aluminum oxides were investigated to determine the efficiency of a pure oxide or mixture of oxides. Samples were sintered at 1750 deg C for 1 hour in a carbon resistance furnace under normal nitrogen atmosphere. Some of them were submitted to hot isostatic pressing to remove all close-porosity. A detailed study of densification was performed by dilatometric analysis. Shape and grain size, formed phases and their distribution and composition were evaluated by X-ray diffraction, scanning electron microscopy and energy dispersive spectroscopy. Hardness and fracture toughness values were determined by using the indentation method. Oxidation tests were conducted under static air at 1400 deg C for 64 hours into a tubular furnace. The results showed that samples with gadolinium oxide additions and mixture of oxides achieved higher fracture toughness values and greater oxidation resistance, although these specimens had reached lower densification than those with lanthanum oxide additions. Hot isostatic pressing increased the hardness but decreased the fracture toughness of the material. (author)

  16. The addition of aluminium to ruthenium liner layers for use as copper diffusion barriers

    Energy Technology Data Exchange (ETDEWEB)

    McCoy, A.P., E-mail: anthony.mccoy2@mail.dcu.ie; Bogan, J.; Walsh, L.; Byrne, C.; Casey, P.; Hughes, G.

    2014-07-01

    The chemical interaction of Al on a SiO₂ dielectric layer and the addition of Al into Ru thin films on SiO₂ for use as copper diffusion barrier layers are assessed in situ using X-ray photoelectron spectroscopy. Thin (~1–2 nm) Al films were deposited on a SiO₂ substrate and in a separate experiment on a 3 nm Ru liner layer on SiO₂, and both Al/SiO₂ and Al/Ru/SiO₂ structures were subsequently thermally annealed. Results indicate the reduction of SiO₂ and the subsequent formation of Al₂O₃ with the release of Si from the dielectric. The Al/Ru/SiO₂ structure showed evidence for the diffusion of Al through the Ru layer and the subsequent interaction of the Al with the underlying SiO₂ dielectric to form Al₂O₃. In this case, the reduction of SiO₂ leads to the release of Si from the dielectric and the subsequent chemical interaction of Ru with Si.

  17. Corrosion of research reactor aluminium clad spent fuel in water. Additional information: Report of the work done in Poland

    International Nuclear Information System (INIS)

    The first Polish reactor EWA, and the second reactor MARIA, are the two sources of research reactor spent nuclear fuel in Poland. EWA operated from 1958 to 1995, and MARIA operates since 1974 until now. At first, it was planned that the research reactor spent fuel would be returned to the country of origin, the Soviet Union. But after the political, economical and social transformation of the Soviet Union into the Russian Federation, and transformations in countries of the Central and Eastern Europe, the problem of the research reactor spent fuel management had to be addressed again, taking into consideration the radically new conditions. Since the beginning the nuclear fuel discharged from the reactors has been stored in a water pool, which means that some stored spent fuel has been stored in wet conditions for more than 40 years. During the period of 1997 - 2003, complex investigations of spent fuel and storage quality conditions were performed. Some damage was found to the storage facilities, which were repaired. Also, it was found that intensive corrosion processes had taken place, especially in the longer stored spent fuel. As a result, a programme to migrate the consequences of damaged spent fuel assemblies, transferring it from wet to dry storage, was established, and a programme to investigate corrosion processes of aluminium in storage pool water was established. Within the framework of the programme, four experimental racks containing aluminium coupons were placed in two spent fuel storage pools. They contained samples of aluminium alloys: Al 6061, Al 6063 and SZAV1. Two of the racks were extracted from the pools after a 1-year storage and the other two after a 2-years storage. The coupons were subsequently examined using visual and metallurgical methods. The results of the investigation are presented in this report. (author)

  18. Contribution to the study of remedy solutions to uranium(molybdenum)/aluminium interactions: role of silicon addition to aluminium, study of coupled effects

    International Nuclear Information System (INIS)

    In the project development and qualification program of a nuclear fuel with Low Enriched Uranium for Materials Testing Reactors, the dispersed U(Mo)/Al fuel is being developed due to its excellent stability during irradiation. However, in pile experiments showed that depending on the irradiation conditions (e.g. high burnup or high heat flux), an extensive interaction occurs between the fissile element U(Mo) and the Al based matrix resulting in swelling, which could eventually lead to a fuel plate failure. Among the ways to improve the behavior of the dispersed U(Mo) fuel, the solution now seen as the reference remedy by the entire scientific community is the addition of silicon into the aluminum matrix. In order to provide some understanding and optimizing the solution 'Si additions into Al matrix' under neutron irradiation, an out of pile study is performed on (i) the interaction mechanisms involved in the U(Mo)/Al (Si) system and (ii) the impact of the Si additions into the Al matrix on alternative solutions to the U(Mo)/Al interactions, namely the modification of the γ-U(Mo) fissile compound by adding a third element and/or modifying the interface between the γ-U(Mo) fissile compound and the matrix. This document provides a mechanistic description of the U(7Mo)/Al(Si) interaction for a range of Si content in Al between 2 and 10 wt.%, based on the multi-scale characterization of diffusion couples. The location of the Mo and its role in the reaction mechanisms are demonstrated. The influence of elements X = Y, Cu, Zr, Ti, Cr, on the U (Mo)/Al and U (Mo)/Al (Si) interactions mechanisms was then studied. It is shown that adding a third element to the U(Mo) alloy acts on the second order on diffusion kinetics and (micro)structure of the interaction layer compared to the addition of Si into Al. Finally, an alumina coating which shows a potential interest to improve the performance of the fuel has been developed. (author)

  19. The influence of nitrogen and oxygen additions on the thermal characteristics of aluminium-based thin films

    International Nuclear Information System (INIS)

    The ternary aluminium oxynitride (AlNxOy) system offers the possibility to obtain a wide range of properties by tailoring the ratio between pure Al, AlNx and AlOy and therefore opening a significant number of possible applications. In this work the thermal behaviour of AlNxOy thin films was analysed by modulated infrared radiometry (MIRR), taking as reference the binary AlOy and AlNx systems. MIRR is a non-contact and non-destructive thermal wave measurement technique based on the excitation, propagation and detection of temperature oscillations of very small amplitudes. The intended change of the partial pressure of the reactive gas (N2 and/or O2) influenced the target condition and hence the deposition characteristics which, altogether, affected the composition and microstructure of the films. Based on the MIRR measurements and their qualitative and quantitative interpretation, some correlations between the thermal transport properties of the films and their chemical/physical properties have been found. Furthermore, the potential of such technique applied in this oxynitride system, which present a wide range of different physical responses, is also discussed. The experimental results obtained are consistent with those reported in previous works and show a high potential to fulfil the demands needed for the possible applications of the systems studied. They are clearly indicative of an adequate thermal response if this particular thin film system is aimed to be applied in small sensor devices or in electrodes for biosignal acquisition, such as those for electroencephalography or electromyography as it is the case of the main research area that is being developed in the group. - Highlights: • AlNx, AlOy and AlNxOy films were deposited by magnetron sputtering. • Discharge characteristics were compared between systems. • Different x and y coefficients were obtained. • Composition, structure and morphology were correlated with physical properties. • Thermal

  20. The influence of nitrogen and oxygen additions on the thermal characteristics of aluminium-based thin films

    Energy Technology Data Exchange (ETDEWEB)

    Borges, J., E-mail: joelborges@fisica.uminho.pt [Centro de Física, Universidade do Minho, Campus de Gualtar, 4710-057 Braga (Portugal); Department of Control Engineering, Faculty of Electrical Engineering, Czech Technical University in Prague, Technická 2, Prague 6 (Czech Republic); Macedo, F. [Centro de Física, Universidade do Minho, Campus de Gualtar, 4710-057 Braga (Portugal); Couto, F.M. [Physics Sciences Laboratory, Norte Fluminense State University, 28013-602 Campos–RJ (Brazil); Rodrigues, M.S.; Lopes, C. [Centro de Física, Universidade do Minho, Campus de Gualtar, 4710-057 Braga (Portugal); Instituto Pedro Nunes, Laboratório de Ensaios, Desgaste e Materiais, Rua Pedro Nunes, 3030-199 Coimbra (Portugal); Pedrosa, P. [Centro de Física, Universidade do Minho, Campus de Gualtar, 4710-057 Braga (Portugal); SEG-CEMUC, Mechanical Engineering Department, University of Coimbra, 3030-788 Coimbra (Portugal); Universidade do Porto, Faculdade de Engenharia, Departamento de Engenharia Metalúrgica e de Materiais, Rua Dr. Roberto Frias, s/n, 4200-465 Porto (Portugal); Polcar, T. [Department of Control Engineering, Faculty of Electrical Engineering, Czech Technical University in Prague, Technická 2, Prague 6 (Czech Republic); Engineering Materials & nCATS, FEE, University of Southampton, Highfield Campus, SO17 1BJ, Southampton (United Kingdom); Marques, L.; Vaz, F. [Centro de Física, Universidade do Minho, Campus de Gualtar, 4710-057 Braga (Portugal)

    2015-08-01

    The ternary aluminium oxynitride (AlN{sub x}O{sub y}) system offers the possibility to obtain a wide range of properties by tailoring the ratio between pure Al, AlN{sub x} and AlO{sub y} and therefore opening a significant number of possible applications. In this work the thermal behaviour of AlN{sub x}O{sub y} thin films was analysed by modulated infrared radiometry (MIRR), taking as reference the binary AlO{sub y} and AlN{sub x} systems. MIRR is a non-contact and non-destructive thermal wave measurement technique based on the excitation, propagation and detection of temperature oscillations of very small amplitudes. The intended change of the partial pressure of the reactive gas (N{sub 2} and/or O{sub 2}) influenced the target condition and hence the deposition characteristics which, altogether, affected the composition and microstructure of the films. Based on the MIRR measurements and their qualitative and quantitative interpretation, some correlations between the thermal transport properties of the films and their chemical/physical properties have been found. Furthermore, the potential of such technique applied in this oxynitride system, which present a wide range of different physical responses, is also discussed. The experimental results obtained are consistent with those reported in previous works and show a high potential to fulfil the demands needed for the possible applications of the systems studied. They are clearly indicative of an adequate thermal response if this particular thin film system is aimed to be applied in small sensor devices or in electrodes for biosignal acquisition, such as those for electroencephalography or electromyography as it is the case of the main research area that is being developed in the group. - Highlights: • AlN{sub x}, AlO{sub y} and AlN{sub x}O{sub y} films were deposited by magnetron sputtering. • Discharge characteristics were compared between systems. • Different x and y coefficients were obtained.

  1. Comparative study on welding characteristics of laser-additional current hybrid welded T-joint of aluminium and titanium alloy

    Directory of Open Access Journals (Sweden)

    Zhang Xinge

    2015-01-01

    Full Text Available In order to improve the properties of laser overlap welded T-joint, laser-additional current hybrid welding process is put forward. In this paper, the welding characteristics of laser-additional current hybrid welded aluminum and titanium alloy T-joint were conducted and compared. The weld width at faying surface increase, which results in tensile shear load increasing compared with those of laser welding for both aluminum and titanium alloy, but the effect of current on aluminum alloy is more obvious. The porosity defect within the laser-additional current hybrid welded joint sharply reduces compared with that within laser welding. The tensile shear load of aluminum alloy and titanium alloy hybrid welded joints respectively increase 21% and 15%. The effects of additional current on welding characteristics of aluminum alloy and titanium alloy are compared and analyzed.

  2. Comparative study on welding characteristics of laser-additional current hybrid welded T-joint of aluminium and titanium alloy

    OpenAIRE

    Zhang Xinge; Li Liqun; Chen Yanbin; Zhu Xiaocui; Li Yansheng; Guo Xinjian

    2015-01-01

    In order to improve the properties of laser overlap welded T-joint, laser-additional current hybrid welding process is put forward. In this paper, the welding characteristics of laser-additional current hybrid welded aluminum and titanium alloy T-joint were conducted and compared. The weld width at faying surface increase, which results in tensile shear load increasing compared with those of laser welding for both aluminum and titanium alloy, but the effect of current on aluminum alloy is mor...

  3. The Effect of Cu and Ge Additions on Strength and Precipitation in a lean 6xxx Aluminium Alloy

    Science.gov (United States)

    Mørtsell, E. A.; Marioara, C. D.; Andersen, S. J.; Røyset, J.; Reiso, O.; Holmestad, R.

    2015-10-01

    It has been demonstrated that the strength loss in a lean Al-Mg-Si alloy due to solute reduction could be compensated by back-adding a lower at % of Ge and Cu. Nanosized precipitate needles which are the main cause of strength in these alloys, and material hardness has been correlated to parameters quantified by TEM. It was found that additions of Ge and Cu strongly affect the precipitation process by increasing precipitate density and reducing precipitate size. Investigations of precipitate atomic structure by HAADF-STEM indicated that they contain mixed areas of known phases and disordered regions. A hexagonal Si/Ge-network was found to be present in all precipitate cross sections.

  4. The prophylactic reduction of aluminium intake.

    Science.gov (United States)

    Lione, A

    1983-02-01

    The use of modern analytical methods has demonstrated that aluminium salts can be absorbed from the gut and concentrated in various human tissues, including bone, the parathyroids and brain. The neurotoxicity of aluminium has been extensively characterized in rabbits and cats, and high concentrations of aluminium have been detected in the brain tissue of patients with Alzheimer's disease. Various reports have suggested that high aluminium intakes may be harmful to some patients with bone disease or renal impairment. Fatal aluminium-induced neuropathies have been reported in patients on renal dialysis. Since there are no demonstrable consequences of aluminium deprivation, the prophylactic reduction of aluminium intake by many patients would appear prudent. In this report, the major sources of aluminium in foods and non-prescription drugs are summarized and alternative products are described. The most common foods that contain substantial amounts of aluminium-containing additives include some processed cheeses, baking powders, cake mixes, frozen doughs, pancake mixes, self-raising flours and pickled vegetables. The aluminium-containing non-prescription drugs include some antacids, buffered aspirins, antidiarrhoeal products, douches and haemorrhoidal medications. The advisability of recommending a low aluminium diet for geriatric patients is discussed in detail. PMID:6337934

  5. Composite Nickel Coatings Produced on 6XXX Series Aluminium Alloys with the Addition of Vanadium / Kompozytowe Powłoki Niklowe Wytwarzane Na Stopach Aluminum Serii 6XXX Z Dodatkiem Wanadu

    Directory of Open Access Journals (Sweden)

    Nowak M.

    2015-12-01

    Full Text Available Studies of composite nickel coatings electrolytically deposited on aluminium alloys with different content of vanadium were described. Composite coatings were deposited from a Watts bath containing fine-dispersed SiC powder particles in an amount of 20 g/l and organic matters such as saccharin and sodium laurate. The morphology, structure and thickness of the obtained composite coatings were presented. The corrosion resistance of produced coatings was examined by electrochemical method. Basing on the results of studies it was found that coatings obtained with the sole addition of saccharin were characterized by numerous surface defects. The addition of sodium laurate eliminated the occurrence of defects caused by hydrogen evolution and the resulting coatings were continuous with good adhesion to the substrate. The distribution of the ceramic SiC phase in coatings was fairly uniform for all the examined variants of aluminium alloys. SEM examinations did not reveal the phenomenon of the ceramic particles agglomeration.

  6. Automotive Aluminium Recycling

    Energy Technology Data Exchange (ETDEWEB)

    Gelas, B. des

    2000-07-01

    This paper aims at providing an overview on the contribution of aluminium recycling in the supply of new aluminium for automotive applications. Based on a presentation on how the global European automotive aluminium supply requirements are met, an analysis of the present and future contribution of automotive aluminium recycling is first presented. Current situation and future developments for automotive aluminium recycling practices are then commented, together with an outline on design principles for easier aluminium recycling. (orig.)

  7. Aluminium structural elements

    OpenAIRE

    Švent, Nejc

    2016-01-01

    This thesis focuses on the structural analysis of aluminium structural members in accordance with the SIST EN 1999-1-1 standard. In the introduction, historical development of aluminium is summarized, as well as the processes of structural aluminium production and manufacture. Predominantly, resistance control checks of aluminium structural members are covered, with special attention to the major contrasts between aluminium and steel structural analyses. Finally, fundamental examples of resis...

  8. Effect of molybdenum addition on aluminium grain refined by titanium on its metallurgical and mechanical characteristics in the as cast condition and after pressing by the equal angular channel process

    International Nuclear Information System (INIS)

    Aluminium and its alloys are versatile materials which are widely used in industrial and engineering applications due to their attractive characteristics. However, they solidify in columnar structure which tends to reduce their surface quality and mechanical strength. It is therefore, grain refined by grain refiners i.e. titanium or titanium+boron. The equal angular channel pressing, ECAP, process is a recent method for producing severe plastic deformation in materials. In this research work, the effect of addition of molybdenum either alone or in the presence of titanium to commercially pure aluminium on microstructure and mechanical behaviour is investigated in two conditions; first, in the as cast condition, and second after pressing by the ECAP process at room temperature. It was found that addition of Ti alone at a rate of 0.15% weight to commercially pure Al resulted in grain refining of microstructure and a grain size of 91μm was obtained. However, after pressing by the ECAP process further refinement was achieved and the grain size was reduced to 18μm. Addition of Mo alone to aluminium at a rate of 0.1% resulted in grain size of 76μm in the as cast condition and 32μm after pressing by the ECAP process. The combination of the two elements Ti and Mo together resulted in 48μm grain size in the as cast condition, compared to 40μm after pressing by the ECAP process. Furthermore, it was found that in the as cast condition: addition of Ti alone to Al resulted in enhancement of its mechanical behaviour by an increase of 5.2% increase in its flow stress at 20% true strain, whereas addition of Mo either alone or in the presence of Ti resulted in decrease of its flow stress at 20% by 9% and 5.6% respectively. However, after pressing by ECAP: it was found that addition of Ti or Mo either alone or together to Al resulted in increase of its flow stress at 20 % strain by the following percentages 5.49, 4.74 and 10.3% respectively

  9. Recent developments in advanced aircraft aluminium alloys

    International Nuclear Information System (INIS)

    Highlights: • To compete with composites, performance of aluminium alloys should be increased. • Al–Li alloys have higher strength, fracture and fatigue/corrosion resistance. • Improvements of aerospace Al alloys are due to optimised solute content and ratios. • In selecting new materials, there should be no reduction in the level of safety. • The use of hybrid materials could provide additional opportunities for Al alloys. - Abstract: Aluminium alloys have been the primary material for the structural parts of aircraft for more than 80 years because of their well known performance, well established design methods, manufacturing and reliable inspection techniques. Nearly for a decade composites have started to be used more widely in large commercial jet airliners for the fuselage, wing as well as other structural components in place of aluminium alloys due their high specific properties, reduced weight, fatigue performance and corrosion resistance. Although the increased use of composite materials reduced the role of aluminium up to some extent, high strength aluminium alloys remain important in airframe construction. Aluminium is a relatively low cost, light weight metal that can be heat treated and loaded to relatively high level of stresses, and it is one of the most easily produced of the high performance materials, which results in lower manufacturing and maintenance costs. There have been important recent advances in aluminium aircraft alloys that can effectively compete with modern composite materials. This study covers latest developments in enhanced mechanical properties of aluminium alloys, and high performance joining techniques. The mechanical properties on newly developed 2000, 7000 series aluminium alloys and new generation Al–Li alloys are compared with the traditional aluminium alloys. The advantages and disadvantages of the joining methods, laser beam welding and friction stir welding, are also discussed

  10. Ongoing characterization of passivated aluminium nanopowders

    Energy Technology Data Exchange (ETDEWEB)

    Kwok, Q.S.M.; Fouchard, R.C.; Turcotte, A-M.; Abdel-Qader, Z.; Jones, D.E.G. [Natural Resources Canada, CANMET, Canadian Explosives Research Laboratory, Ottawa, ON (Canada)

    2002-04-01

    For characterization, the thermal behaviour of two aluminium nanopowders - Alss and Alssef - in air was determined using differential scanning calorimetry (DSC), simultaneous thermogravimetry-DTA (TG-DTA) and accelerating rate calorimetry (ARC). Alss and Alssef were found to be less reactive to air than previously determined for Als And Alex, possibly due to their thicker and different type of passivating layer. Stability determination for Alss and Alssef in a wet oxidizing environment was carried out using ARC, whereas outgassing behaviour of mixtures of ammonium dinitramide (ADN) and the various aluminium powders was investigated using TG-DTA-FTIR-MS (Fourier Transform Infrared Spectrometry-Mass Spectrometry). The addition of various aluminium powders resulted in only minimal effect on the thermal stability of ADN. Electrostatic discharge, friction sensitivities of ADN and its mixtures with various aluminium powders, and thermal stability and sensitivity of mixtures of nano-sized molybdenum trioxide with aluminium nanopowders were also studied. The electrostatic discharge sensitivity of molybdenum trioxide was shown to increase by the addition of aluminium nanopowders. 23 refs., 5 tabs., 7 figs.

  11. Multiply-negatively charged aluminium clusters and fullerenes

    Energy Technology Data Exchange (ETDEWEB)

    Walsh, Noelle

    2008-07-15

    Multiply negatively charged aluminium clusters and fullerenes were generated in a Penning trap using the 'electron-bath' technique. Aluminium monoanions were generated using a laser vaporisation source. After this, two-, three- and four-times negatively charged aluminium clusters were generated for the first time. This research marks the first observation of tetra-anionic metal clusters in the gas phase. Additionally, doubly-negatively charged fullerenes were generated. The smallest fullerene dianion observed contained 70 atoms. (orig.)

  12. Rows of Dislocation Loops in Aluminium Irradiated by Aluminium Ions

    DEFF Research Database (Denmark)

    Henriksen, L.; Johansen, A.; Koch, J.;

    1967-01-01

    Single-crystal aluminium specimens, irradiated with 50-keV aluminium ions, contain dislocation loops that are arranged in regular rows along <110 > directions. ©1967 The American Institute of Physics......Single-crystal aluminium specimens, irradiated with 50-keV aluminium ions, contain dislocation loops that are arranged in regular rows along <110 > directions. ©1967 The American Institute of Physics...

  13. Study on hardening mechanisms in aluminium alloys

    Directory of Open Access Journals (Sweden)

    P. K. Mandal

    2016-01-01

    Full Text Available The Al-Zn-Mg alloys are most commonly used age-hardenable aluminium alloys. The hardening mechanism is further enhanced in addition of Sc. Sc additions to aluminium alloys are more promising. Due to the heterogeneous distribution of nano-sized Al3Sc precipitates hardening effect can be accelerated. Mainly, highlight on hardening mechanism in Al-Zn-Mg alloys with Sc effect is to study. In addition, several characterisations have been done to age-hardening measurements at elevated temperatures from 120oC to 180 oC. The ageing kinetics has also been calculated from Arrhenius equation. Furthermore, friction stir processing (FSP can be introduced to surface modification process and hardened the cast aluminium alloys. In this study, hardening mechanism can be evaluated by Vicker’s hardness measurement and mechanical testing is present task.

  14. Role of aluminium addition on structure of Fe substituted Fe73.5−Si13.5B9Nb3Cu1Al alloy ribbons

    Indian Academy of Sciences (India)

    Gautam Agarwal; Himanshu Agrawal; M Srinivas; B Majumdar; N K Mukhopadhyay

    2013-08-01

    The investigation has dealt with the structure and magnetic properties of rapidly solidified and annealed Fe73.5−Si13.5B9Nb3Cu1Al ( = 0, 2, 4, 6 at%) ribbons prepared by melt spinning. Complete amorphous structure was obtained in as-spun ribbons of = 0 and 2 at% compositions, whereas structure of ribbons containing higher Al was found to be partially crystalline. Detailed thermal analyses of the alloys and the melt spun ribbons revealed that the glass forming ability in the form of x/l (ratio between crystallization and liquidus temperature) is the highest for 2 at% Al alloys and decreases with further addition of Al. Annealing of all as spun ribbons resulted in the precipitation of nanocrystalline phase embedded in amorphous matrix in the form of either 3 phase or -Fe(Si/Al) solid solution depending on the initial composition of the alloy. Only -Fe(Si/Al) solid solution was formed in 2 at% Al ribbons whereas ordered DO3 structure was found to be stabilized in other ribbons including 0 at% Al. A detailed study on determination of precision lattice parameter of nanocrystalline phase revealed that the lattice parameter increases with the addition of Al indicating the partitioning behaviour of Al in nanocrystalline phase.

  15. Effect of Additives on Properties of Flame Retardant LLDPE with Magnesium Carbonate/Aluminium Hydroxide Compound%助剂对氢氧化铝和碳酸镁复配阻燃LLDPE性能的影响

    Institute of Scientific and Technical Information of China (English)

    李建新; 吴洁

    2011-01-01

    将协效剂白炭黑、硼酸锌、低熔点玻璃和硅烷偶联剂、铝酸脂偶联剂分别添加到碳酸镁/氢氧化铝复配阻燃的线型低密度聚乙烯(LLDPE)体系中,考察了这些助剂对体系阻燃性能和力学性能的影响.结果表明:几种助剂对体系的氧指数影响较小;白炭黑可以明显提高体系的拉伸强度,硼酸锌对体系的断裂伸长率影响最小;对拉伸强度而言,使用铝酸脂偶联剂优于硅烷偶联剂.%Several synergistic agents and two kind of coupling agents were added into the fame-retardant LLDPE system with magnesium carbonate and aluminium hydroxide compound, and the effects of additives on the flame retardant and mechanical properties of LLDPE system were studied.The results show that several synergistic agents have slight effect on oxygen index of the system, silica can improve the tensile strength evidently, and zinc borate has little influence on the elongation at break of the system. As far as the tensille strength is concerned, aluminate coupling agent is better than silane coupling agent.

  16. Rapidly solidified aluminium for optical applications

    OpenAIRE

    Gubbels, G.P.H.; Venrooy, B.W.H.; Bosch, A.J.; Senden, R

    2008-01-01

    This paper present the results of a diamond turning study of a rapidly solidified aluminium 6061 alloy grade, known as RSA6061. It is shown that this small grain material can be diamond turned to smaller roughness values than standard AA6061 aluminium grades. Also, the results are nearly as good as nickel plated surfaces, but the RSA6061 has the advantage that no additional production steps are needed and that no bi-metallic bending or delamination can occur in a thermally changing environmen...

  17. Recovery in aluminium

    DEFF Research Database (Denmark)

    Gundlach, Carsten

    2006-01-01

    growth curves are represented as strings. To identify the strings a combination of a 5D connected component type algorithm and multi-peak fitting was found to be superior. The first use of the method was a study of recovery of a deformed aluminium alloy (AA1050). The aluminium alloy was deformed by cold......In the present thesis the development of a unique experimental method for volume characterisation of individual embedded crystallites down to a radius of 150 nm is presented. This method is applied to in-situ studies of recovery in aluminium. The method is an extension of 3DXRD microscopy, an X......-ray diffraction technique for studies of the evolution of grains within polycrystalline materials. The much smaller volume of the crystallites of interest here in comparison to grains implies that the existing method is not applicable due to overlap of diffraction spots. In this work this obstacle is overcome by...

  18. Soldering of aluminium alloys

    International Nuclear Information System (INIS)

    A literature survey about soldering in general and aluminium alloys soldering in particular is presented. The existing methods of soldering aluminium alloys are described. These include soldering with flux, soldering after preliminary plating, vacuum brazipressure and temperature (NTP), sample age calculation based on 14C half life of 5570 and 5730 years, age correction for NTP, dendrochronological corrections and the relative radiocarbon concentration. All results are given with one standard deviation. Input data test (Chauvenet's criterion), gas purity test, standard deviation test and test of the data processor are also included in the program. (author)

  19. Fire exposed aluminium structures

    NARCIS (Netherlands)

    Maljaars, J.; Fellinger, J.H.H.; Soetens, F.

    2006-01-01

    Material properties and mechanical response models for fire design of steel structures are based on extensive research and experience. Contrarily, the behaviour of aluminium load bearing structures exposed to fire is relatively unexplored. This article gives an overview of physical and mechanical pr

  20. Optimization of Magnesium Metal into Commercially Pure Aluminium

    Directory of Open Access Journals (Sweden)

    Vandana J Rao

    2014-02-01

    Full Text Available The present investigation, involve development of Al-Mg systems by addition of magnesium into commercially pure aluminium. The amounts of magnesium added into commercially pure aluminium are of 1 and 2 wt%. The recoveries of magnesium are around 85-90%.Remaining Mg react with oxygen and float on the liquid aluminium. Presence of magnesium creates two phenomena. One is solid solution hardening and other is intermetallics formation. Both the phenomena checked by microstructural changes and by measuring the electrical conductivity values. By increasing the Mg, content mechanical properties (hardness and tensile strength increases and electrical conductivity decreases.

  1. The effect of rare earth metal additions and superheat on the microstructure and mechanical properties of the A319 aluminium alloy; L'effet de l'addition des metaux de terres rares et de la surchauffe sur la microstructure et les proprietes mecaniques de l'alliage d'aluminium A319

    Energy Technology Data Exchange (ETDEWEB)

    Saoudi, A.; Samuel, F.H.; Samuel, A.M. [Quebec Univ. a Chicoutimi, Dept. des Sciences Appliquees, PQ (Canada); Doty, H.W. [GM Powertrain, Metal Casting Technology, Inc., Milford, New Hampshire (United States)

    2003-12-01

    This study concerns the influence of certain metallurgical factors, like the addition of a mixture of rare earth metals (misch-metal) and of overheating, on the microstructure and the tensile properties of alloy A319-2 (Al-Si-Cu with 0.4, 0.8 and 1.2 % iron) The new phase linked with misch-metal has a needle - and/or platelet - shape as the {beta}-iron phase and impedes the flow of the liquid metal during casting, thus creating porosity. The different types of particles present in the microstructure remain after the T6 thermal treatment. In the alloys containing 1.2 % iron, the length of the {beta} phase and misch-metal particles is slightly smaller than in the alloys with 0.4 % Fe or 0.8 % Fe, after the addition of 5 % misch-metal and overheating at 950 deg C. This explains the better tensile elongation of the 1.2%Fe-5% misch-metal alloy cast at 950 deg C instead of 750 deg C. UTS and yield strength are decreased by the addition of misch-metal but are slightly improved by overheating. Overheating at 950 deg C decreases the yield strength only in the 1.2% Fe-0% misch-metal alloy. (authors)

  2. Recovery in aluminium

    OpenAIRE

    Gundlach, Carsten

    2006-01-01

    In the present thesis the development of a unique experimental method for volume characterisation of individual embedded crystallites down to a radius of 150 nm is presented. This method is applied to in-situ studies of recovery in aluminium. The method is an extension of 3DXRD microscopy, an X-ray diffraction technique for studies of the evolution of grains within polycrystalline materials. The much smaller volume of the crystallites of interest here in comparison to grains implies that the ...

  3. Synthesis of aluminium nanoparticles by arc evaporation of an aluminium cathode surface

    Indian Academy of Sciences (India)

    M Gazanfari; M Karimzadeh; S Ghorbani; M R Sadeghi; G Azizi; H Karimi; N Fattahi; Z Karimzadeh

    2014-06-01

    Aluminium nanoparticles (Al Nps) are synthesized using arc discharge method by applying direct current between aluminium electrodes in liquid environment without any use of vacuum equipment, heat exchangers, high temperatures furnaces and inert gases. After synthesis of Al Nps, in situ coating process on the nanoparticles was performed immediately. The effects of media on the yield and morphology of aluminium nanoparticles were investigated. Analysis result of the samples indicated that particle size was less than 30 nm, when 120 A/cm2 arc current was used. In addition, coating agent can affect arc velocity, arc stability, morphology and composition of the nanoparticles. Resultant nanoparticles were identified using X-ray powder diffraction (XRD), also their surface morphology was studied by scanning electron microscopy (SEM) and transmission electron microscopy (TEM) and finally the accuracy of coating was assessed with infrared (IR) spectroscopy.

  4. Aluminium and human breast diseases.

    Science.gov (United States)

    Darbre, P D; Pugazhendhi, D; Mannello, F

    2011-11-01

    The human breast is exposed to aluminium from many sources including diet and personal care products, but dermal application of aluminium-based antiperspirant salts provides a local long-term source of exposure. Recent measurements have shown that aluminium is present in both tissue and fat of the human breast but at levels which vary both between breasts and between tissue samples from the same breast. We have recently found increased levels of aluminium in noninvasively collected nipple aspirate fluids taken from breast cancer patients (mean 268 ± 28 μg/l) compared with control healthy subjects (mean 131 ± 10 μg/l) providing evidence of raised aluminium levels in the breast microenvironment when cancer is present. The measurement of higher levels of aluminium in type I human breast cyst fluids (median 150 μg/l) compared with human serum (median 6 μg/l) or human milk (median 25 μg/l) warrants further investigation into any possible role of aluminium in development of this benign breast disease. Emerging evidence for aluminium in several breast structures now requires biomarkers of aluminium action in order to ascertain whether the presence of aluminium has any biological impact. To this end, we report raised levels of proteins that modulate iron homeostasis (ferritin, transferrin) in parallel with raised aluminium in nipple aspirate fluids in vivo, and we report overexpression of mRNA for several S100 calcium binding proteins following long-term exposure of MCF-7 human breast cancer cells in vitro to aluminium chlorhydrate. PMID:22099158

  5. Method of aluminium fluoride manufacture

    International Nuclear Information System (INIS)

    The manufacture of aluminium fluoride is based on waste processing in uranium hexafluoride conversion to uranium oxides within the fuel cycle. The conversion is the stoichiometric conversion of uranium hexafluoride with aluminium nitrate to uranyl nitrate. This is extracted from the water phase by phosphoric acid trialkyl ester to an organic solvent and further processed. The discharge water phase is solidified by evaporation to solid aluminium fluoride and nitric acid. (M.S.)

  6. First Principles Study of Aluminium Vacancy in Wurtzite Aluminium Nitride

    Institute of Scientific and Technical Information of China (English)

    GAO Ting-Ge; YI Jue-Min; ZHOU Zi-Yao; HU Xiao-Dong

    2008-01-01

    @@ We report that the aluminium vacancy in wurtzite AIN brings about two impurity levels e and a2 in the band gap, not just one single t2 level The aluminium vacancy carries a magnetic moment of 1 μB in the ground state. The molecule orbit of the aluminium vacancy becomes e↑↑ a2↑ rather than e↑↑ a2↑. The calculation is carried out by using the CASTEP code. The intrinsic symmetry of wurtzite A1N is the driving force for this spin splitting. Finally the symmetry of wurtzite AlN results in an anti-ferromagnetic coupling between the aluminium vacancies, as is predicted. Our findings are helpful to gain a more through understanding of the structural and spin property of aluminium vacancy in wurtzite AIN.

  7. Thermoelectric power in low-density interstitial-free iron-aluminium alloys

    Science.gov (United States)

    Rana, Radhakanta; Liu, Cheng

    2013-09-01

    Thermoelectric power (TEP) studies on low-density interstitial-free iron-aluminium alloys reveal that the TEP decreases with increase in the aluminium content on account of the introduction of lattice dispersion centres. The TEP coefficients, determined from the Nordheim-Gorter law, for 6.8 and 8.1 wt.% aluminium additions to α-iron are found to be higher than values reported in previous literature for small aluminium additions. The grain size has a very weak effect on the TEP of these alloys.

  8. FSW characterization of 6082 aluminium alloys sheets

    OpenAIRE

    K. Mroczka; A. Pietras

    2009-01-01

    Purpose: The purpose of the investigations was to elaborate a set of FSW parameters for connecting 6082 aluminium alloy sheets allowing to produce welds of highest strength.Design/methodology/approach: The FSW was tried at different speeds and at additional cooling. The welds microstructure was studied using optical and scanning electron microscopes. The mechanical properties of produced connections are discussed regarding their tensile test and microhardness measurements.Findings: The FSW we...

  9. Quantitative evaluation of the aluminium titanate formation

    International Nuclear Information System (INIS)

    Samples of aluminium titanate were obtained under isothermal sintering condition in equimolar Al2 O3 Ti O2 powder mixtures at different soaking time intervals. The formation of Al2 Ti O5 and the effect of Si O2 additive in the reaction and densification were analysed. Quantitative evaluation of Al2 Ti O5 was performed by the Rietveld method and by using an internal standard. Both methods were considered appropriated for the presented purpose. (author)

  10. Advances in development and application of aluminium batteries

    DEFF Research Database (Denmark)

    Qingfeng, Li; Zhuxian, Qiu

    2001-01-01

    Aluminium has long attracted attention as a potential battery anode because of its high theoretical voltage and specific energy. The protective oxide layer at aluminium surface is however detrimental to its performance to achieve its reversible potential, and also causing the delayed activation of...... anode. The oxide layer can be removed by e.g. amalgamation but this will result in accelerated corrosion and poor shelf life. These difficulties have been successfully overcome by developing alloying elements and electrolyte additives in the recent years. The literature review also includes various...... aluminium batteres, especially aluminium-air batteries, and a wide range of their applications from emergency power supplies, reserve batteries field portable batteries, to batteries for electric vehicles and underwater propulsion....

  11. Effects of Aluminium Sulfate on Cadmium Accumulation in Rice

    International Nuclear Information System (INIS)

    Full text: Cadmium accumulation in Pathum Thani 1 and Suphan Buri 60 rice cultivars was investigated upon treatment with aluminium sulfate as a precipitant. Rice was grown hydroponically in a medium containing 4 ppm cadmium nitrate with or without 4 ppm aluminium sulfate. Root, stem with leaves and grain samples were collected and analyzed for cadmium content using atomic absorption spectroscopy and inductively coupled plasma atomic emission spectroscopy. Without the addition of aluminium sulfate, Pathum Thani 1 and Suphan Buri 60 accumulated 24.71∫ 3.14 ppm and 34.43 ∫ 4.51 ppm (dry weight of whole plant) of cadmium, respectively. With aluminium sulfate, cadmium accumulation increased to 40.66 ∫ 2.47 ppm and 62.94 ∫ 10.69 ppm, respectively. The addition of aluminium sulfate to the planting medium did not reduce cadmium accumulation but caused the rice to accumulate more cadmium especially in the shoots and grains. This observation might serve as the basis for future research on the management of agricultural areas that are contaminated with cadmium and aluminium

  12. Aluminium, antiperspirants and breast cancer.

    Science.gov (United States)

    Darbre, P D

    2005-09-01

    Aluminium salts are used as the active antiperspirant agent in underarm cosmetics, but the effects of widespread, long term and increasing use remain unknown, especially in relation to the breast, which is a local area of application. Clinical studies showing a disproportionately high incidence of breast cancer in the upper outer quadrant of the breast together with reports of genomic instability in outer quadrants of the breast provide supporting evidence for a role for locally applied cosmetic chemicals in the development of breast cancer. Aluminium is known to have a genotoxic profile, capable of causing both DNA alterations and epigenetic effects, and this would be consistent with a potential role in breast cancer if such effects occurred in breast cells. Oestrogen is a well established influence in breast cancer and its action, dependent on intracellular receptors which function as ligand-activated zinc finger transcription factors, suggests one possible point of interference from aluminium. Results reported here demonstrate that aluminium in the form of aluminium chloride or aluminium chlorhydrate can interfere with the function of oestrogen receptors of MCF7 human breast cancer cells both in terms of ligand binding and in terms of oestrogen-regulated reporter gene expression. This adds aluminium to the increasing list of metals capable of interfering with oestrogen action and termed metalloestrogens. Further studies are now needed to identify the molecular basis of this action, the longer term effects of aluminium exposure and whether aluminium can cause aberrations to other signalling pathways in breast cells. Given the wide exposure of the human population to antiperspirants, it will be important to establish dermal absorption in the local area of the breast and whether long term low level absorption could play a role in the increasing incidence of breast cancer. PMID:16045991

  13. Aluminium oxide exoelectron dosimetry

    Energy Technology Data Exchange (ETDEWEB)

    Akselrod, M.S.; Odegov, A.L. (Urals State Technical Univ., Ekaterinburg (Russian Federation)); Durham, J.S. (Pacific Northwest Lab., Richland, WA (United States))

    1994-01-01

    The exoemission properties of aluminium oxide ([alpha]-Al[sub 2]O[sub 3]:C), in the forms of both a single crystal and of powder, have been investigated. Measurements obtained during readout in a vacuum showed that irradiated Al[sub 2]O[sub 3]:C dosemeters emit exoelectrons with a sensitivity that is 10-20 times higher than that achievable using beryllium oxide (BeO) exoelectron dosemeters (EEDs). This paper presents results of studies using a commercial methane gas reader. The investigators studied the response of the Al[sub 2]O[sub 3]:C EEDs as a function of beta energy and measured the dose-response relationship. The effect of humidity on the dosemeter response was also investigated. (Author).

  14. 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.

  15. Roll bonding of strained aluminium

    DEFF Research Database (Denmark)

    Staun, Jakob M.

    2003-01-01

    This report investigates roll bonding of pre-strained (å ~ 4) aluminium sheets to produce high strain material from high purity aluminium (99.996%) and commercial pure aluminium (99.6%). The degree of bonding is investigated by optical microscopy and ultrasonic scanning. Under the right...... circumstances both materials show good bonding, but the high purity material is excluded because of recrystallisation and the resulting loss of mechanical properties. The effect of cross stacking and roll bonding pre-strained sheets of the commercial purity material is investigated and some dependence of the...... cross rolled volume fraction is found. To further asses this effect, and the anisotropy, it is necessary to acquire knowledge about both texture and microstructure, e.g. by TEM. Roll bonding of pre-strained aluminium is found to be a possible alternative to ARB in the quest for ultra-fine grained...

  16. Aluminium exclusion and aluminium tolerance in woody plants

    Directory of Open Access Journals (Sweden)

    Ivano eBrunner

    2013-06-01

    Full Text Available The aluminium (Al cation Al3+ is highly rhizotoxic and is a major stress factor to plants on acid soils, which cover large areas of tropical and boreal regions. Many woody plant species are native to acid soils and are well adapted to high Al3+ conditions. In tropical regions, both woody Al accumulator and non-Al accumulator plants occur, whereas in boreal regions woody plants are non-Al accumulators. The mechanisms of these adaptations can be divided into those that facilitate the exclusion of Al3+ from root cells (exclusion mechanisms and those that enable plants to tolerate Al3+ once it has entered the root and shoot symplast (internal tolerance mechanisms. The biochemical and molecular basis of these mechanisms have been intensively studied in several crop plants and the model plant Arabidopsis. In this review, we examine the current understanding of Al3+ exclusion and tolerance mechanisms from woody plants. In addition, we discuss the ecology of woody non-Al accumulator and Al accumulator plants, and present examples of Al3+ adaptations in woody plant populations. This paper complements previous reviews focusing on crop plants and provides insights into evolutionary processes operating in plant communities that are widespread on acid soils.

  17. Friction surfacing of aluminium alloys

    OpenAIRE

    Pereira, Diogo Jorge O. A.

    2012-01-01

    Friction surfacing is a solid state joining process that has attracted much interest in the past decades. This technology allows joining dissimilar metallic materials while avoiding the brittle intermetallic formations, involving temperatures bellow melting point and producing like forged metal structures. Much research using different steels has been made but the same does not happen with aluminium alloys, specially using different aluminium alloys. Friction surface coatings using cons...

  18. Comparison of the x-ray attenuation properties of breast calcifications, aluminium, hydroxyapatite and calcium oxalate

    International Nuclear Information System (INIS)

    Aluminium is often used as a substitute material for calcifications in phantom measurements in mammography. Additionally, calcium oxalate, hydroxyapatite and aluminium are used in simulation studies. This assumes that these materials have similar attenuation properties to calcification, and this assumption is examined in this work. Sliced mastectomy samples containing calcification were imaged at ×5 magnification using a digital specimen cabinet. Images of the individual calcifications were extracted, and the diameter and contrast of each calculated. The thicknesses of aluminium required to achieve the same contrast as each calcification when imaged under the same conditions were calculated using measurements of the contrast of aluminium foils. As hydroxyapatite and calcium oxalate are also used to simulate calcifications, the equivalent aluminium thicknesses of these materials were also calculated using tabulated attenuation coefficients. On average the equivalent aluminium thickness was 0.85 times the calcification diameter. For calcium oxalate and hydroxyapatite, the equivalent aluminium thicknesses were 1.01 and 2.19 times the thickness of these materials respectively. Aluminium and calcium oxalate are suitable substitute materials for calcifications. Hydroxyapatite is much more attenuating than the calcifications and aluminium. Using solid hydroxyapatite as a substitute for calcification of the same size would lead to excessive contrast in the mammographic image. (note)

  19. Effect of additives on magnesium carbonate and aluminium hydroxide compound with flame-retardant polyethylene system%添加剂对阻燃聚乙烯体系性能的影响

    Institute of Scientific and Technical Information of China (English)

    李建新; 吴洁

    2011-01-01

    为提高碳酸镁/氢氧化铝复配阻燃聚乙烯体系的性能,将几种常用协效剂和两种偶联剂添加到阻燃体系中,测量其阻燃性能及力学性能.实验表明:几种添加剂对提高体系的氧指数贡献相当;白炭黑可以明显提高体系的拉伸强度,硼酸锌对体系的断裂伸长率影响最小.对于拉伸强度、使用铝酸酯偶联剂效果优于硅烷偶联剂.%To improve the property of magnesium carbonate and aluminium hydroxide compound with flame-retardant PE sys tem,several synergistic agents and two kind of eoupling agents were added into the flame-retardant PE system. The fire retard ant property and mechanical property were tested. It indicates that several synergistic agents have similar contribution to oxy gen index of the system, silica white can improve the tenslle strength evidently, and zinc borate has little influence on the e longation at break of the system. As far as the tensile strength is concerned , aluminate coupling agent is better than silane cou pling agent.

  20. Effect of hydrogen on aluminium and aluminium alloys: A review

    DEFF Research Database (Denmark)

    Ambat, Rajan; Dwarakadasa, E.S.

    1996-01-01

    Susceptibility of aluminium and its alloys towards hydrogen embrittlement has been well established. Still a lot of confusion exists on the question of transport of hydrogen and its possible role in stress corrosion cracking. This paper reviews some of the fundamental properties of hydrogen in...... aluminium and its alloys and its effect on mechanical properties. The importance of hydrogen embrittlement over anodic dissolution to explain the stress corrosion cracking mechanism of these alloys is also examined in considerable detail. The various experimental findings concerning the link between...

  1. Bioactive type glass-ceramics within incorporated aluminium

    International Nuclear Information System (INIS)

    Bioactive glass-ceramics are used as biomaterials for the reparation of bone tissue. They are prepared, generally, by bioglass of specific composition for each particular use. The aluminium addition in the formulation at very small quantities influences on the structural properties. Two glass-ceramics obtained by P2O5-Na2O-CaO-SiO2 formulation within aluminium (0.5 % in Al2O3 base) added through a reactive alumina and purified feldspar were analyzed. The results showed structural differences between both glass-ceramics. (author)

  2. Uptake of aluminium ion by the liver

    International Nuclear Information System (INIS)

    The specific uptake by the rat liver of 28Al was shown. There was specific uptake of 28Al by liver cell nuclei and DNA. This uptake was blocked by prior treatment with stable aluminium. It is concluded that aluminium enters the liver cell by some specific mechanism and that the reaction of aluminium with DNA inside the hepatocyte nucleus could be a mechanism responsible for the development of aluminium-induced experimental porphyria in the rat

  3. Pressureless sintered silicon carbide tailored with aluminium nitride sintering agent

    International Nuclear Information System (INIS)

    This study reports the influence of aluminium nitride on the pressureless sintering of cubic phase silicon carbide nanoparticles (β-SiC). Pressureless sintering was achieved at 2000 degrees C for 5 min with the additions of boron carbide together with carbon of 1 wt% and 6 wt%, respectively, and a content of aluminium nitride between 0 and 10 wt%. Sintered samples present relative densities higher than 92%. The sintered microstructure was found to be greatly modified by the introduction of aluminium nitride, which reflects the influence of nitrogen on the β-SiC to α-SiC transformation. The toughness of sintered sample was not modified by AlN incorporation and is relatively low (around 2.5 MPa m1/2). Materials exhibited transgranular fracture mode, indicating a strong bonding between SiC grains. (authors)

  4. IEC 61267: Feasibility of type 1100 aluminium and a copper/aluminium combination for RQA beam qualities.

    Science.gov (United States)

    Leong, David L; Rainford, Louise; Zhao, Wei; Brennan, Patrick C

    2016-01-01

    In the course of performance acceptance testing, benchmarking or quality control of X-ray imaging systems, it is sometimes necessary to harden the X-ray beam spectrum. IEC 61267 specifies materials and methods to accomplish beam hardening and, unfortunately, requires the use of 99.9% pure aluminium (Alloy 1190) for the RQA beam quality, which is expensive and difficult to obtain. Less expensive and more readily available filters, such as Alloy 1100 (99.0% pure) aluminium and copper/aluminium combinations, have been used clinically to produce RQA series without rigorous scientific investigation to support their use. In this paper, simulation and experimental methods are developed to determine the differences in beam quality using Alloy 1190 and Alloy 1100. Additional simulation investigated copper/aluminium combinations to produce RQA5 and outputs from this simulation are verified with laboratory tests using different filter samples. The results of the study demonstrate that although Alloy 1100 produces a harder beam spectrum compared to Alloy 1190, it is a reasonable substitute. A combination filter of 0.5 mm copper and 2 mm aluminium produced a spectrum closer to that of Alloy 1190 than Alloy 1100 with the added benefits of lower exposures and lower batch variability. PMID:26776501

  5. Buckwheat stomatal traits under aluminium toxicity

    Directory of Open Access Journals (Sweden)

    Oleksandr E. Smirnov

    2014-04-01

    Full Text Available Aluminium influence on some stomatal parameters of common buckwheat (Fagopyrum esculentum Moench. was studied. Significant changes in stomatal density, stomatal index and stomatal shape coefficient under aluminium treatment were revealed. Stomatal closure and no difference in total stomatal potential conductance index of treatment plants were suggested as aluminium resistance characteristics.

  6. Dynamical study of liquid aluminium

    International Nuclear Information System (INIS)

    Recent molecular dynamics data of Ebbsjoe et al. in liquid aluminium have been analysed through the memory function formalism. Two forms of the memory functions which have correct asymptotic limit at large wavenumbers but accounts for interatomic correlations in a different manner are considered. The results for ω2s(q, ω) obtained from both models are compared with experimental data. (author)

  7. Aluminium foams. manufacture, properties and applications

    International Nuclear Information System (INIS)

    Aluminium foams are porous to have many interesting combinations of physical and mechanical properties, such as high stiffness in conjunction with very low specific weight. The aluminium foam structure, manufacture processes, physical, chemical and mechanical properties and applications are reviewed in this paper. The various manufacturing processes are classified according to the state of matter in which the metal is processed. Liquid aluminium can be foamed directly by injecting gas or gas-releasing blowing agents. Indirect methods include melting of powder compacts which contain a blowing agent. An inert gas entrapped in powder compacts can produce aluminium foams in solid state after heat treatment. Electron-deposition or metal vapour deposition also allow for the production of aluminium foams. Physical, chemical and mechanical properties and the various ways for characterising the aluminium foams are reviewed in second section of this paper. finally, the various application fields for aluminium foams are discussed. They are divided into different industrial sectors. (Author) 75 refs

  8. Electrochemical properties and thermal stability of epoxy coatings electrodeposited on aluminium and modified aluminium surfaces

    Directory of Open Access Journals (Sweden)

    ZORICA M. KACAREVIC-POPOVIC

    2001-12-01

    Full Text Available The corrosion behaviour of epoxy coatings electrodeposited on aluminium, as well as on electrochemically and chemically modified aluminium were investigated during exposure to 3 % NaCl. Electrochemical impedance spectroscopy (EIS and thermogravimetric analysis (TGA were used for the determination of the protective properties of epoxy coatings on aluminium, anodized aluminium, phosphatized and chromatized-phosphatized aluminium. The protective properties of epoxy coatings on anodized and chromatized-phosphatized aluminium are significantly improved with respect to the same epoxy coatings on aluminium and phosphatized aluminium: higher values of the pore resitance and charge-transfer resistance, lower values of the coating capacitance, double-layer capacitance and relative permittivity (from EIS smaller amount of absorbed water inside the coating (From TGA. On the other hand, the lower values of the ipdt temperature indicate a lower thermal stability of the epoxy coatings on anodized and chromatized-phosphatized aluminium.

  9. Wire + Arc Additive Manufacturing

    OpenAIRE

    Williams, Stewart W.; Martina, Filomeno; Addison, Adrian C.; Ding, Jialuo; Pardal, Goncalo; Colegrove, Paul A.

    2016-01-01

    Depositing large components (>10 kg) in titanium, aluminium, steel and other metals is possible using Wire + Arc Additive Manufacturing. This technology adopts arc welding tools and wire as feedstock for additive manufacturing purposes. High deposition rates, low material and equipment costs, and good structural integrity make Wire+Arc Additive Manufacturing a suitable candidate for replacing the current method of manufacturing from solid billets or large forgings, especially with regards to ...

  10. Friction Welding of Aluminium and Aluminium Alloys with Steel

    Directory of Open Access Journals (Sweden)

    Andrzej Ambroziak

    2014-01-01

    Full Text Available The paper presents our actual knowledge and experience in joining dissimilar materials with the use of friction welding method. The joints of aluminium and aluminium alloys with the different types of steel were studied. The structural effects occurring during the welding process were described. The mechanical properties using, for example, (i microhardness measurements, (ii tensile tests, (iii bending tests, and (iv shearing tests were determined. In order to obtain high-quality joints the influence of different configurations of the process such as (i changing the geometry of bonding surface, (ii using the interlayer, or (iii heat treatment was analyzed. Finally, the issues related to the selection of optimal parameters of friction welding process were also investigated.

  11. Microscopic observation of pattern attack by aggressive ions on finished surface of aluminium alloy sacrificial anode

    International Nuclear Information System (INIS)

    This paper presents the results of a microscopic observation on submerged finished surface of aluminium alloy sacrificial anode. Experimental tests were carried out on polished surface aluminium anode exposed to seawater containing aggressive ions in order to observe of pattern corrosion attack on corroding surface of anode. Results have shown, at least under the present testing condition, that surface of sacrificial anode were attack by an aggressive ion such as chloride along grain boundaries. In addition, results of microanalysis showed that the corrosion products on surface of aluminium alloy have Al, Zn and O element for all sample and within the pit was consists of Al, Zn, O and Cl element. (author)

  12. Metallurgical Characterisation of Recovered Aluminium Alloys in Cameroon

    Directory of Open Access Journals (Sweden)

    T. Tchotang

    2013-07-01

    Full Text Available This article is a comparative study of metallurgical characteristics of the different aluminium alloys gotten through recycling of recovered aluminium in Cameroon. A simple experimental device for the foundry of secondary aluminium blend, of very good quality built around a movable charcoal furnace is presented. It enables better energy efficiency, a better distribution of the heat around the crucible and indirectly assures good quality of the products obtained, while respecting the economic constraints and users' safety. Six refining methods are proposed by the addition of polyvinyl chloride (method A, coke rich in carbon CHS (method C, ammonium chloride NH4Cl (method E, manganese dioxide MnO (method T, acrylic nitrite (C2H3Cln (method P and sodium chloride NaCl (method S. A critical analysis of the different recycling techniques is presented as well as a proposed process of melting and refining that enables the obtaining products with high degrees of purity. The results are then compared to the results obtained from the industrial methods of aluminium refining such as fractional crystallization (FC, granular filtration (GF and dissolution in a metal solvent (DS. The later (DS gives the rate of 6.540% of accumulated alloy elements and enables the best purification (93.460%, while the NaCl gives the lowest global rate of additive elements (9.478%, with the best purity index (90.522% amount the proposed methods. Results obtained show that this method of refining improves the metallurgical properties of secondary aluminium alloy blends and guarantees better safety, as well as reducing the risks of environmental pollution.

  13. On the chemical and electrochemical formation of aluminium carbide in aluminium electrolysis

    OpenAIRE

    Bronislav, Novák

    2013-01-01

    Cathode wear is considered as one of the key factors for limiting the lifetime of aluminium electrolysis cells. This phenomenon has become more important as aluminium smelters have steadily increased the amperage of the cells and shifted towards graphitized cathode materials with higher electrical conductivity. The present work has focused on the fundamentals of the formation of aluminium carbide at the carbon-aluminium interface. The objective was to investigate the mechanism(s) of the forma...

  14. Determination of aluminium in food with aluminiferous food additives in Futian district of Shenzhen%深圳市福田区含铝食物添加剂的食品中铝含量的测定

    Institute of Scientific and Technical Information of China (English)

    丘汾; 李可; 刘奋; 杨梅; 黄慧萍; 戴京晶; 蒋立新

    2012-01-01

    Objective:To detect aluminum content in various foods with aluminiferous food additives during the course of production. Methods:Four classes of foods suspected to contain aluminiferous food additives in Futian district were taken as the main detection objects. 245 samples were selected and determined by ICP - MS. Results; Most of the samples(99% ) were found with aluminum and aluminum content varied widely, which may be in relation to the different uses of aluminiferous food additives and food formulation. Conclusion: Aluminiferous food additives were generally used in the course of food processing. Some food with Aluminiferous food additives, such as steamed buns, steamed cake and baked food, were frequently eaten by citizens, which would be prejudicial to health of these people due to aluminum toxicity.%目的:检测深圳市福田区在制造和加工过程中使用含铝食物添加剂的各种食品的铝含量.方法:集中检测4类可能加入含铝食物添加剂的食物,从本市区内共抽取245个样本,用电感耦合等离子体质谱仪测定.结果:大部分样本(99%)均检出含有铝.铝含量相差很大;可能与食物制造时使用含铝食物添加剂及食物制造配方不同有关.结论:含铝食物添加剂普遍使用在食品加工,一些经常食用加入含铝食物添加剂的食品(例如蒸包或蒸糕、烘焙食品)的市民不排除他们的健康会受到铝毒性影响的可能性.

  15. Aluminium Process Fault Detection and Diagnosis

    OpenAIRE

    Nazatul Aini Abd Majid; Taylor, Mark P; Chen, John J. J.; Brent R. Young

    2015-01-01

    The challenges in developing a fault detection and diagnosis system for industrial applications are not inconsiderable, particularly complex materials processing operations such as aluminium smelting. However, the organizing into groups of the various fault detection and diagnostic systems of the aluminium smelting process can assist in the identification of the key elements of an effective monitoring system. This paper reviews aluminium process fault detection and diagnosis systems and propo...

  16. A bakable aluminium vacuum chamber with an aluminium flange and metal seal for ultrahigh vacuum

    International Nuclear Information System (INIS)

    A bakable (2000C) aluminium alloy vacuum chamber (6063-T6) with an aluminium alloy (2219-T87) flange and metal seal (Helicoflex-HN: aluminium O-ring) has been constructed. Such components may be used in the construction of the vacuum chamber in proton synchrotrons and electron storage rings. (author)

  17. Toxicity of aluminium on five aquatic invertebrates; Aluminiums toksisitet paa 5 akvatiske invertebrater

    Energy Technology Data Exchange (ETDEWEB)

    Moe, J. [Oslo Univ. (Norway)

    1996-01-01

    The conference paper deals with the experiments done by investigating the effects from the toxicity of aluminium on aquatic invertebrates. The aim of the experiments was to compare the toxicity of unstable aluminium compounds with stable forms of aluminium. 8 refs., 2 figs., 2 tabs.

  18. Aluminium in foodstuffs and diets in Sweden.

    Science.gov (United States)

    Jorhem, L; Haegglund, G

    1992-01-01

    The levels of aluminium have been determined in a number of individual foodstuffs on the Swedish market and in 24 h duplicate diets collected by women living in the Stockholm area. The results show that the levels in most foods are very low and that the level in vegetables can vary by a factor 10. Beverages from aluminium cans were found to have aluminium levels not markedly different from those in glass bottles. Based on the results of the analysis of individual foods, the average Swedish daily diet was calculated to contain about 0.6 mg aluminium, whereas the mean content of the collected duplicate diets was 13 mg. A cake made from a mix containing aluminium phosphate in the baking soda was identified as the most important contributor of aluminium to the duplicate diets. Tea and aluminium utensils were estimated to increase the aluminium content of the diets by approximately 4 and 2 mg/day, respectively. The results also indicate that a considerable amount of aluminium must be introduced from other sources. PMID:1542992

  19. Use of Propranolol-Magnesium Aluminium Silicate Intercalated Complexes as Drug Reservoirs in Polymeric Matrix Tablets

    OpenAIRE

    T. Pongjanyakul; S Rojtanatanya

    2012-01-01

    The objective of the present study was to investigate the use of propranolol-magnesium aluminium silicate intercalated complexes as drug reservoirs in hydroxypropylmethylcellulose tablets. The matrix tablets containing the complexes were prepared and characterised with respect to propranolol release and were subsequently compared with those loading propranolol or a propranolol-magnesium aluminium silicate physical mixture. Additionally, the effects of varying viscosity grades of hydroxypropyl...

  20. Sol-gel derived nanocomposite materials for corrosion protection of aluminium alloys

    OpenAIRE

    Schmidt, Helmut K.; Müller, Peter; Dittfurth, Carola; Albayrak, Sener; Puhl, Anne

    2000-01-01

    Thermally curable nanocomposite coating materials have been developed to seal and protect copper-containing aluminium alloys against corrosion. The coating material was prepared via the sol-gel-process starting from epoxy functionalised silanes, nanoscaled silica and organic diole crosslinker. This coating matrix was additionally supplied with a varying content of cerium oxide (1-20 wt.%). The corrosion protective efficiency of these coatings was investigated on aluminium alloys Al 6013-T6 an...

  1. Corrosion of research reactor aluminium clad spent fuel in water

    International Nuclear Information System (INIS)

    A large variety of research reactor spent fuel with different fuel meats, different geometries and different enrichments in 235U are presently stored underwater in basins located around the world. More than 90% of these fuels are clad in aluminium or aluminium based alloys that are notoriously susceptible to corrosion in water of less than optimum quality. Some fuel is stored in the reactor pools themselves, some in auxiliary pools (or basins) close to the reactor and some stored at away-from-reactor pools. Since the early 1990s, when corrosion induced degradation of the fuel cladding was observed in many of the pools, corrosion of research reactor aluminium clad spent nuclear fuel stored in light water filled basins has become a major concern, and programmes were implemented at the sites to improve fuel storage conditions. The IAEA has since then established a number of programmatic activities to address corrosion of research reactor aluminium clad spent nuclear fuel in water. Of special relevance was the Coordinated Research Project (CRP) on Corrosion of Research Reactor Aluminium Clad Spent Fuel in Water (Phase I) initiated in 1996, whose results were published in IAEA Technical Reports Series No. 418. At the end of this CRP it was considered necessary that a continuation of the CRP should concentrate on fuel storage basins that had demonstrated significant corrosion problems and would therefore provide additional insight into the fundamentals of localized corrosion of aluminium. As a consequence, the IAEA started a new CRP entitled Corrosion of Research Reactor Aluminium Clad Spent Fuel in Water (Phase II), to carry out more comprehensive research in some specific areas of corrosion of aluminium clad spent nuclear fuel in water. In addition to this CRP, one of the activities under IAEA's Technical Cooperation Regional Project for Latin America Management of Spent Fuel from Research Reactors (2001-2006) was corrosion monitoring and surveillance of research

  2. Aluminium exclusion and aluminium tolerance in woody plants

    OpenAIRE

    Ivano eBrunner; Christoph eSperisen

    2013-01-01

    The aluminium (Al) cation Al3+ is highly rhizotoxic and is a major stress factor to plants on acid soils, which cover large areas of tropical and boreal regions. Many woody plant species are native to acid soils and are well adapted to high Al3+ conditions. In tropical regions, both woody Al accumulator and non-Al accumulator plants occur, whereas in boreal regions woody plants are non-Al accumulators. The mechanisms of these adaptations can be divided into those that facilitate the exclusion...

  3. Buffering effects on electrograining of aluminium in nitric acid

    Energy Technology Data Exchange (ETDEWEB)

    Koroleva, E.V. [Corrosion and Protection Centre, UMIST, P.O. Box 88, Manchester M60 1QD (United Kingdom)]. E-mail: e.koroleva@umist.ac.uk; Thompson, G.E. [Corrosion and Protection Centre, UMIST, P.O. Box 88, Manchester M60 1QD (United Kingdom); Skeldon, P. [Corrosion and Protection Centre, UMIST, P.O. Box 88, Manchester M60 1QD (United Kingdom); Hollrigl, G. [Alcan Technology and Management Ltd., Bad. Bahnhofstrasse 16, CH-8212 Neuhausen (Switzerland); Lockwood, S. [Bridgnorth Aluminium Limited, Stourbridge Road, Bridgnorth WV15 6AU (United Kingdom); Smith, G. [Bridgnorth Aluminium Limited, Stourbridge Road, Bridgnorth WV15 6AU (United Kingdom)

    2005-09-01

    Electrograining of a binary Al-Si alloy has been undertaken in nitric acid based electrolytes, with the resultant surfaces examined by scanning and transmission electron microscopies. Depending on electrograining conditions, the pit appearance varies from hemispherical to large lateral pits, with the latter favoured in relatively acidic electrolytes. The conditions prevailing in the pit have been explored through use of aluminium ion additions to the nitric acid electrolyte as well as additions of species which influence the precipitation and dissolution of aluminium hydroxide. These confirm that control of the pit solution pH, through hydroxide generation, as a result of the selected electrograining conditions and consequent anodic and cathodic polarisation, enables tailoring of the resultant electrograined surface appearance.

  4. Study and Elimination of the Interference of Aluminium on the Voltammetric Determination of Uranium with Chloranilic Acid. Application to the Determination of Uranium in Waters and Geological Samples

    International Nuclear Information System (INIS)

    The interference of aluminium during the voltammetric determination of uranium with 2,5-dichloro-3,6-dihydroxy-1,4-benzoquinone (chloranilic acid) has been investigated. The presence of aluminium originates a voltammetric signal due to its chloranilic acid complex at the same potential range as the uranium analytical signal appears. The interference of aluminium can be overcome by addition of an appropriate amount of sodium fluoride as complexing reagent. The determination of uranium by adsorptive stripping voltammetry (AdSV) can be carried out at concentration levels as low as 1 μg/L in the presence of 100 μg/L aluminium after the addition of 100μL of 0.1 mol/L NaF. The method can be applied to the determination of uranium in aluminium-containing waters and geological samples containing high aluminium levels. (Author) 19 refs

  5. Contradictory effect of chromate inhibitor on corrosive wear of aluminium alloy

    International Nuclear Information System (INIS)

    Research highlights: → Corrosive wear of aluminium alloy in inhibited artificial acid rain was studied. → Tribometer with linear reciprocating ball-on-flat geometry was used.→ Corrosion potential, polarization current and friction coefficient were measured. → Chromate decreases corrosion of aluminium alloy under wear conditions. → Chromate in general accelerates corrosive wear of the alloy in acid rain. - Abstract: The corrosive wear of D16T aluminium alloy in artificial acid rain was studied. A special tribometer with the linear reciprocating ball-on-flat geometry was used. The setup allows to measure simultaneously an open circuit potential, to carry out potentiostatic and potentiodynamic polarization studies of the alloy corrosion and to record the friction coefficient. It was established that the addition of strontium chromate inhibitor to the working environment decreases an electrochemical corrosion of the aluminium alloy under wear conditions, but in general accelerates its destruction due to insufficient wear resistance of a formed surface film.

  6. Analysis of compressive strength in flatwise and edgewise direction to characterize Al-7000 aluminium foam

    Science.gov (United States)

    Sutarno, Soepriyanto, Syoni; Korda, Akhmad A.; Dirgantara, Tatacipta

    2015-09-01

    The physical mechanical properties of Al-7000 aluminium foam product and processing has been evaluated in this study. The characterization through the compressive testing refers to flatwise direction provided more confident result than edgewise direction. This experiment may correlate with formation of side products of calcia alumina and alumina silica that involved in metal mixture of aluminium foam. These compounds are formed from additional calcium carbonate and silica in the mixture. Calcium carbonate (CaCO3) roles as a blowing agent source of carbon dioxide (CO2). The formation of calcia alumina (CaO.Al2O3) may role to strengthen of cell wall of aluminium foam and to improve the viscosity of melting metal. The Al-7000 aluminium foam indicated a decrease of compressive strength probably due to existence of alumina silica (3Al2O3.SiO2) in the metal mixture.

  7. Evaluation of mechanical properties of aluminium alloy–alumina–boron carbide metal matrix composites

    International Nuclear Information System (INIS)

    Highlights: • Fabrication of MMC with aluminium alloy–alumina–boron carbide is done. • Different proportions of reinforcements are added. • The effects of varying proportions are studied. • Investigation on mechanical properties above composites is performed. • Failure morphology analysis is done using SEM. - Abstract: This paper deals with the fabrication and mechanical investigation of aluminium alloy, alumina (Al2O3) and boron carbide metal matrix composites. Aluminium is the matrix metal having properties like light weight, high strength and ease of machinability. Alumina which has better wear resistance, high strength, hardness and boron carbide which has excellent hardness and fracture toughness are added as reinforcements. Here, the fabrication is done by stir casting which involves mixing the required quantities of additives into stirred molten aluminium. After solidification, the samples are prepared and tested to find the various mechanical properties like tensile, flexural, impact and hardness. The internal structure of the composite is observed using Scanning Electron Microscope (SEM)

  8. Aluminium and nickel in human albumin solutions

    DEFF Research Database (Denmark)

    Gammelgaard, Bente; Sandberg, E

    1989-01-01

    Five different brands of commercially available human albumin solutions for infusion were analysed for their aluminium and nickel contents by atomic absorption spectrometry. The aluminium concentrations ranged from 12 micrograms/l to 1109 micrograms/l and the nickel concentrations ranged from 17...

  9. Preparation of aluminium lakes by electrocoagulation

    Directory of Open Access Journals (Sweden)

    Prapai Pradabkham

    2008-07-01

    Full Text Available Aluminium lakes have been prepared by electrocoagulation employing aluminium as electrodes. The electrocoagulation is conducted in an aqueous alcoholic solution and is completed within one hour. The dye content in the lake ranges approximately between 4-32%.

  10. Development of microstructure during sintering and aluminium exposure of titanium diboride ceramics

    Energy Technology Data Exchange (ETDEWEB)

    Pettersen, Gunnar

    1997-12-31

    In the production of aluminium, much less energy need be consumed if an inert, wetted cathode is present in the electrolysis cell. Titanium diboride, TiB{sub 2}, is easily wetted and does not readily dissolve in liquid aluminium, but it degrades, probably because aluminium penetrates into it during electrolysis. This degradation is linked to impurities present in the TiB{sub 2} after sintering. This thesis studies the sintering process and how aluminium penetrates into the material. High-purity, high-density TiB{sub 2} compacts were made by hot pressing at 50 MPa in an argon atmosphere at 1790-1960 {sup o}C. Samples were made with different impurity additions. These samples were exposed to liquid aluminium at 980 {sup o}C for 24 hours. All samples were penetrated, but the amount and appearance depended on the sintering aid used. Unlike the other samples, pure TiB{sub 2} was easily penetrated by metallic aluminium because of the open porosity and microcracks of this material. Grain boundary penetration was common among the samples. Differences in penetration behaviour between grain boundaries are probably due to differences in grain boundary energy. But no relation to segregants or boundary misorientation was found. The orientation of grain boundary planes and de-wetting of thin films upon cooling may explain the observed microstructure development. The samples sintered with Ti addition suffered extensive penetration despite their high densities. The grain boundaries of these samples became faceted and contained thicker films of metallic aluminium, presumably because of increased solubility due to iron segregations. All secondary phases present in the grain junctions after sintering, except from the B{sub 4}C phase, reacted with the penetrated aluminium. This did not cause swelling and cracking, as has been suggested by other authors. 101 refs., 48 figs., 7 tabs.

  11. Fabrication experience of aluminium clad aluminium matrix dispersion fuels at BARC

    International Nuclear Information System (INIS)

    Aluminium clad, aluminium matrix plate type dispersion fuels have been fabricated in BARC in recent years as part of fuel development programme for small non-power research reactors. The present paper describes the flowsheet developed for fabrication of Al-UAlx, Al-U3Si2 and Al-U3O8 fuels at BARC. The Al-20% U alloy fuel for KAMINI neutron radiography reactor was prepared by 'melting and casting' route, followed by picture framing and roll-bonding. For higher 'U' density fuels namely, Al-UAlx, Al-U3O8 and Al-U3Si2 the 'powder metallurgy' route was followed for preparation of fuel meat. The novel features in fabrication route were: addition of Zr for stabilizing UAl3 phase in Al-20% U alloy; x-ray radiography and microdensitometric scanning of radiographs for location of fuel outline inside fuel element and for confirming homogeneous distribution of fissile atoms; immersion ultrasonic testing for confirming good bonding between mating Al surface of the fuel plate. (author)

  12. Shot peening of aluminium alloys

    International Nuclear Information System (INIS)

    Shot peening is a process of cold-hammering where a metallic surface is pelted with spherical grains. Each grain bumping into the surface acts as a hammer head and creates a small crater. The overlapping of these craters produces a residual compression layer just underneath the surface. It is well known that cracks cannot spread in a compression zone. In most cases of fatigue rupture and stress corrosion cracks propagate from the surface towards the inside so shot peening allows a longer lifetime of castings. Moreover most materials present a better resistance due to the cold-hammering effect of shot peening. Metallic surfaces can be treated in workshops or directly on site. Typical pieces that undergo shot peening on site are storing tanks, gas and steam turbines, tubes of steam generators and piping in oil or nuclear or chemical industries. This article describes shot peening from a theoretical and general point of view and presents the application to aluminium-lithium alloys. In the case of aluminium alloys shot peening can be used to shape the piece (peen-forming). (A.C.)

  13. Method for aluminium dross utilization

    International Nuclear Information System (INIS)

    A new hydrometallurgical method has been developed for metal aluminum utilization from secondary aluminum dross. Secondary aluminum dross is a powder product with an average of 35% aluminium content (below 1mm). It is waste from primary aluminum dross pyrometallurgical flux less treatment in rotary DC electric arc furnace. This method is based on aluminum leaching in copper chloride water solution. As a result an aluminum oxychloride solution and solids, consisting of copper and oxides are obtained. In order to copper chloride solution regenerate hydrochloric acid is added to the solids. The process is simple, quick, economic and safe. The aluminum oxychloride solution contains 56 g/l Al2O3. The molar ratios are Al:Cl=0,5; OH:Al=1. The solution has 32 % basicity and 1,1 g/cm3 density. For increasing the molar ratio of aluminium to chlorine aluminum hydroxide is added to this solution at 80oC. Aluminum hydroxide is the final product from the secondary aluminum dross alkaline leaching. As a result aluminum oxychloride solution of the following composition is prepared: Al2O3 - 180 g/l; Al:Cl=1,88; OH:Al=4,64; basicity 82%; density 1,22 g/cm3, pH=4 -4,5. Aluminum oxychloride solution produced by means of this method can be used in potable and wastewater treatment, paper making, in refractory mixture as a binder etc. (Original)

  14. Corrosion Resistance of Zinc Coatings With Aluminium Additive

    Directory of Open Access Journals (Sweden)

    Votava Jiří

    2014-08-01

    Full Text Available This paper is focused on evaluation of anticorrosion protection of inorganic metal coatings such as hot-dipped zinc and zinc-galvanized coatings. The thickness and weight of coatings were tested. Further, the evaluation of ductile characteristics in compliance with the norm ČSN EN ISO 20482 was processed. Based on the scratch tests, there was evaluated undercorrosion in the area of artificially made cut. Corrosion resistance was evaluated in compliance with the norm ČSN EN ISO 9227 (salt-spray test. Based on the results of the anticorrosion test, there can be stated corrosion resistance of each individual protective coating. Tests were processed under laboratory conditions and may vary from tests processed under conditions of normal atmosphere.

  15. Nano α-alumina powders from aluminium dross waste

    International Nuclear Information System (INIS)

    The paper describes a solvo thermal chemical process to recycle aluminium dross waste into nano α-alumina powder. The process includes washing to remove the unwanted sodium follow by dissolving of this waste with dilute acid. The solvo thermal process then proceed with addition of propanol to crystallize the aluminium hydroxide. XRD analysis of this crystal shows that it belongs to Gibbs site (Al(OH)3). The crystals were then calcined at 1300 degree C where white powder was produced. Characteristic studies were then performed on this powder using XRD, SEM, EDX and particle size analysis showing that it has single α-alumina crystal phase with almost spherical shape. As the initial particle size is coarse and had a mean particle size of 3.80 μm, high speed wet milling was used and enable to reduce it to 0.49 μm. (Author)

  16. Enhanced immune response induced by the addition of Salmonella flagellin to an aluminium hydroxide preparation%沙门氏菌鞭毛蛋白对氢氧化铝制剂疫苗特异性免疫应答的影响

    Institute of Scientific and Technical Information of China (English)

    赵静; 刘玮; 叶玲英; 钱锋; 徐沪济

    2012-01-01

    目的 评估沙门氏菌鞭毛蛋白作为添加剂在氢氧化铝疫苗制剂中的作用. 方法 以卵清蛋白(OVA)为抗原,氢氧化铝(Alhydrogel)为佐剂,鼠伤寒沙门氏菌鞭毛蛋白(FliC)或寡聚脱氧核糖核苷酸CpG-ODN 1826为添加剂,制备OVA/Alhydrogel、OVA/Alhydrogel+ FliC和OVA/Alhydrogel+ CpG-ODN 1826疫苗制剂.BALB/c小鼠随机分成3组,每组6鼠,分别用以上疫苗制剂以肌肉注射的方式免疫2次,间隔28 d.在初次免疫后第28 d和42 d采小鼠血,分离血清,用ELISA法测定血清中抗OVA IgG及亚型.在初次免疫后的第42 d处死小鼠,取脾,制备脾细胞,给予抗原刺激后检测培养上清中γ干扰素(IFN-γ)和白介素4(IL-4)水平. 结果 初次免疫后第42 d,OVA/Alhydrogel+ FliC制剂组OVA/Alhydrogel+ CpG-ODN 1826制剂组和OVA/Alhydrogel制剂组特异IgG滴度分别为(714.75±213.32) Unit、(863.78±355.05)Unit和(267.45±8.49) Unit,差异有统计学意义(P<0.05);前两制剂组比较差异无统计学意义(P>0.05).IgG亚型分析和脾细胞培养上清IFN-γ和IL-4水平测定表明,OVA/Alhydrogel制剂诱导Th2偏向的免疫应答,而在加入沙门氏菌鞭毛蛋白后免疫应答有向Th1/Th2混合型转变的趋势. 结论 沙门氏菌鞭毛蛋白能增强特异性免疫应答反应,有望成为氢氧化铝疫苗制剂的添加剂.%Objective To evaluate the effect of Salmonella flagellin as an additive in an aluminium hydroxide preparation. Methods Ovalbumin (OVA) served as an antigen, aluminium hydroxide (Alhydrogel) served as an adjuvant, and phase I flagellin of Salmonella enterica serovar Typhimurium (FliC) or CpG-ODN 1826 served as an additive. Three vaccine preparations were prepared, namely, OVA/Alhydrogel, OVA/Alhydrogel + FliC, and OVA/Alhydrogel + CpG-ODN 1826. BALB/c mice were randomly divided into three groups of six and intramuscularly immunized two times with a 28-day interval. Mouse immune sera were collected on days 28 and 42 after the first

  17. Epoxy coatings electrodeposited on aluminium and modified aluminium surfaces

    Directory of Open Access Journals (Sweden)

    Lazarević Zorica Ž.

    2002-01-01

    Full Text Available The corrosion behaviour and thermal stability of epoxy coatings electrodeposited on modified aluminum surfaces (anodized, phosphatized and chromatized-phosphatized aluminium were monitored during exposure to 3% NaCl solution, using electrochemical impedance spectroscopy (EIS and thermogravimetric analysis (TGA. Better protective properties of the epoxy coatings on anodized and chromatized-phosphatized aluminum with respect to the same epoxy coatings on aluminum and phosphatized aluminum were obtained: higher values of Rp and Rct and smaller values of Cc and Cd, from EIS, and a smaller amount of absorbed water inside the coating, from TGA. On the other hand, a somewhat lower thermal stability of these coatings was obtained (smaller values of the ipdt temperature. This behavior can be explained by the less porous structure of epoxy coatings on anodized and chromatized-phosphatized aluminum, caused by a lower rate of H2 evolution and better wet ability.

  18. Surface mechanical behaviour of composite Ni-P-fly ash/zincate coated aluminium alloy

    International Nuclear Information System (INIS)

    Ni-P-fly ash coatings were produced on zincate coated 5083 wrought aluminium alloy substrates with the aid of an electroless deposition technique. Structural and chemical characterization of the produced coatings was performed with the aid of X-ray diffraction (XRD), scanning electron microscopy (SEM) and electron dispersive X-ray analysis (EDS) techniques. The Ni-P-fly ash coating was found to consist of an amorphous Ni-P matrix with dispersed fly ash particles. The wear resistance of the Ni-P-fly ash coating on zincate treated aluminium alloy was observed to be higher than that of the bare aluminium alloy, when sliding against a stainless steel counterface. In addition, the adhesion between the Ni-P-fly ash/zincate coating and the aluminium alloy substrate was also studied with a scratch testing apparatus. The adhesion strength of Ni-P-fly ash/zincate coating on the aluminium alloy substrate was observed to be higher in comparison to the Ni-P/zincate coating on the same aluminium alloy.

  19. Investigation of the aluminium-aluminium oxide reversible transformation as observed by hot stage electron microscopy.

    Science.gov (United States)

    Grove, C. A.; Judd, G.; Ansell, G. S.

    1972-01-01

    Thin foils of high purity aluminium and an Al-Al2O3 SAP type of alloy were oxidised in a specially designed hot stage specimen chamber in an electron microscope. Below 450 C, amorphous aluminium oxide formed on the foil surface and was first detectable at foil edges, holes, and pits. Islands of aluminium then nucleated in this amorphous oxide. The aluminium islands displayed either a lateral growth with eventual coalescence with other islands, or a reoxidation process which caused the islands to disappear. The aluminium island formation was determined to be related to the presence of the electron beam. A mechanism based upon electron charging due to the electron beam was proposed to explain the nucleation, growth, coalescence, disappearance, and geometry of the aluminium islands.

  20. Effects of aluminium surface morphology and chemical modification on wettability

    DEFF Research Database (Denmark)

    Rahimi, Maral; Fojan, Peter; Gurevich, Leonid;

    2014-01-01

    -life aluminium surfaces of different morphology: unpolished aluminium, polished aluminium, and aluminium foil, were subjected to surface modification procedures which involved the formation of a layer of hydrophilic hyperbranched polyethyleneglycol via in situ polymerization, molecular vapour deposition of a...... monolayer of fluorinated silane, and a combination of those. The effect of these surface modification techniques on roughness and wettability of the aluminium surfaces was elucidated by ellipsometry, contact angle measurements and atomic force microscopy. We demonstrated that by employing different types of...

  1. Weldability of high strength aluminium-scandium alloys

    International Nuclear Information System (INIS)

    Australia possesses a significant percentage of the world reserves of the ores required for the production of light alloys such as aluminium, magnesium and titanium. However, most of these minerals deposits are exported for processing, losing the potential of value adding benefits. Scandium has been known for some time to possess excellent grain refining properties when alloyed with aluminium. Although this adds considerable benefits to the mechanical properties of these alloys, it has not been fully exploited due to the high cost of producing the scandium metal. Deposits of scandium containing ore have recently been identified in Australia that are far more accessible than other deposits throughout the world. CSIRO Manufacturing Science and Technology had initiated a research project to investigate the effect of scandium and other grain refining additions on the properties of selected aluminium alloys in order to develop the market and maximise the potential benefits from Australian resources. The major objective of the project is to develop high strength aluminum alloys that exhibit good processing characteristics, particularly good weldability

  2. Aluminium Process Fault Detection and Diagnosis

    Directory of Open Access Journals (Sweden)

    Nazatul Aini Abd Majid

    2015-01-01

    Full Text Available The challenges in developing a fault detection and diagnosis system for industrial applications are not inconsiderable, particularly complex materials processing operations such as aluminium smelting. However, the organizing into groups of the various fault detection and diagnostic systems of the aluminium smelting process can assist in the identification of the key elements of an effective monitoring system. This paper reviews aluminium process fault detection and diagnosis systems and proposes a taxonomy that includes four key elements: knowledge, techniques, usage frequency, and results presentation. Each element is explained together with examples of existing systems. A fault detection and diagnosis system developed based on the proposed taxonomy is demonstrated using aluminium smelting data. A potential new strategy for improving fault diagnosis is discussed based on the ability of the new technology, augmented reality, to augment operators’ view of an industrial plant, so that it permits a situation-oriented action in real working environments.

  3. Deformation features of aluminium in tensile tests

    International Nuclear Information System (INIS)

    It is presented a method to analyse stress-strain curves. Plastic and elastic strains were studied. The strains were done by tensile tests in four types of materials: highly pure aluminium, pure aluminium, commercially pure aluminium and aluminium - uranium. The chemical compositions were obtained by spectroscopy analysis and neutron activation analysis. Tensile tests were carried out at three strain rates, at room temperature, 100,200, 300 and 4000C, with knives extensometer and strain-gages to studied the elastic strain region. A multiple spring model based on two springs model to analyse elastic strain caused by tests without extensometers, taking in account moduli of elasticity and, an interactive analysis system with graphic capability were developed. It was suggested a qualitative model to explain the quantized multielasticity of Bell. (M.C.K.)

  4. Investigation & Analysis of Different Aluminium Alloys t

    OpenAIRE

    Nibedita Sethi*¹,; Ajit Senapati²

    2014-01-01

    Aluminium alloy LM-29, A-356 AND A-6060 was fabricated in sand casting method. Mach inability of aluminium alloy LM-29, A-356 AND A-6060 was investigated and evaluate the mach inability studying the different parameter such as cutting force, surface roughness, chip thickness, and power consumption during turning at different cutting speed and constant depth of cut and feed rate. In this paper also studies the mechanical properties means hardness, density and tensile strength o...

  5. Removal of aluminium from drinking water

    International Nuclear Information System (INIS)

    Aluminium in drinking water comes from natural sources and the alum used as coagulant in the water treatment process. Exposure to aluminium has been implicated in dialysis dementia, Parkinson and Alzheimer's disease. Drinking water containing aluminium was considered to be one of the main sources of Al intake into human body. For this reason, the removal of aluminium from drinking water is vital to our health. In this study, removal of aluminium was carried out by using a chelating resin. To achieve the purpose, two chelating resin iontosorb oxin (IO) and poly hydroxamic acid (PHA) were used. The effects of concentration, pH, stirring time and resin amount was investigated. The concentration range varied between 10 and 500 ppb, pH range was between 2 and 12, stirring time between 5 and 60 minutes, and resin amount between 100 and 1500 mg. The optimum conditions of these resins were determined in a batch system. The results obtained showed that the optimum condition to remove aluminium for poly hydroxamic acid and iontosorb was pH 5-8 and pH 4-9; concentration range between 50-500 ppb, and 150-500 ppb, resin amount 200 mg and the stirring time was 20 minutes, respectively. (author)

  6. Additive Manufacturing for Large Products

    OpenAIRE

    Leirvåg, Roar Nelissen

    2013-01-01

    This thesis researches the possibility and feasibility of applying additive manufacturing technology in the manufacturing of propellers. The thesis concerns the production at the foundry Oshaug Metall AS. Their products consist of propellers and other large products cast in Nickel-Aluminium Bronze. This report looks at three approaches and applications for additive manufacturing at the foundry. These are additively manufactured pattern, sand mold and end metal parts. The available \\emph{State...

  7. Heat treatment of aluminium strip coils; Gluehbehandlung von Aluminium-Bandbunden

    Energy Technology Data Exchange (ETDEWEB)

    Schroeder, Dominik; Dambauer, Georg [LOI Thermprocess GmbH, Essen (Germany)

    2012-08-15

    Nowadays, aluminium strip coils are increasingly heat-treated in single-coil lifting hearth furnaces SCL. Flexible, individual heat treatment allows fast reactions to short term requirements for the production of aluminium strip and offers energy saving possibilities. The following report describes the advantages of single-coil hearth furnaces in terms of flexibility, energy consumption and possible configurations. (orig.)

  8. Design of welded aluminium connections (Entwurf und Berechnung von Aluminium Schweissverbindungen)

    NARCIS (Netherlands)

    Soetens, F.

    1998-01-01

    In the past two decades considerable research effort has been put into welded aluminium connections in order to better understand their structural behaviour and to up-date the design rules in the existing standards at the time [1]. Since weids in aluminium are more critical compared to steel, the ab

  9. Aldose-ketose interconversion in pyridine in the presence of aluminium oxide.

    Science.gov (United States)

    Ekeberg, Dag; Morgenlie, Svein; Stenstrøm, Yngve

    2007-10-15

    The reaction rate of the Lobry de Bruyn-Alberda van Ekenstein transformation of aldoses to ketoses in boiling pyridine was strongly increased by the addition of aluminium oxide. In addition to aldose-ketose transformation, 2-epimers of the starting aldoses and 3-epimers of the primarily produced ketoses were formed to some extent, as reported also when these reactions are carried out without aluminium oxide. The relative amounts of the primary ketose and the starting aldose in the reaction mixtures may be explained on the basis of their stability, predicted from reported free energy calculations. Isomerisation of ketoses to aldoses was much slower than the reverse reaction. The relative free energies are also in these cases important, the very stable xylo-2-hexulose gave only 7% and 6% of the aldoses gulose and idose, respectively, after boiling for 7h in pyridine in the presence of aluminium oxide. PMID:17606255

  10. TEM investigation of aluminium containing precipitates in high aluminium doped silicon carbide

    International Nuclear Information System (INIS)

    Full text: Silicon carbide is a promising semiconductor material for applications in high temperature and high power devices. The successful growth of good quality epilayers in this material has enhanced its potential for device applications. As a novel semiconductor material, there is a need for studying its basic physical properties and the role of dopants in this material. In this study, silicon carbide epilayers were grown on 4H-SiC wafers of (0001) orientation with a miscut angle of 8 deg at a temperature of 1550 deg C. The epilayers contained regions of high aluminium doping well above the solubility of aluminium in silicon carbide. High temperature annealing of this material resulted in the precipitation of aluminium in the wafers. The samples were analysed by secondary ion mass spectrometry and transmission electron microscopy. Selected area diffraction studies show the presence of aluminium carbide and aluminium silicon carbide phases. Copyright (2002) Australian Society for Electron Microscopy Inc

  11. Aluminium EN AC-AlSi12 alloy matrix composite materials reinforced by Al2O3 porous preforms

    OpenAIRE

    Nagel, A.; M. Kremzer; L.A. Dobrzański,

    2007-01-01

    Purpose: The purpose of this work is to elaborate the method of manufacturing of composite materials based on porous ceramic preforms infiltrated by eutectic aluminium alloy.Design/methodology/approach: The material for investigations was fabricated by pressure infiltration method of ceramic porous preforms. The eutectic aluminium alloy EN AC – AlSi12 was use as a matrix while as reinforcement were used ceramic preforms fabricated by sintering of Al2O3 Alcoa CL 2500 powder with addition of po...

  12. Water atomised aluminium alloy powders

    Energy Technology Data Exchange (ETDEWEB)

    Neikov, O.D.; Vasilieva, G.I.; Sameljuk, A.V.; Krajnikov, A.V

    2004-10-10

    The new rapid solidification (RS) process based on high-pressure water atomisation (WA) of the melt for manufacturing of advanced aluminium alloys was realised in the form of a pilot plant. The problems of safe operation in the course of Al alloy powder production and powder quality were solved by the use of water solutions of inhibitors, by the control of suspension temperature and hydrogen ion exponent (pH), by the hydraulic classification of atomised products, and by the optimisation of dehydration procedure. The rate of powder-water interaction strongly depends on the value of pH. While the rate of room temperature reactions is very slow at pH 3.0-4.0, the increase of pH to 6.0 leads to an intensive powder oxidation. A set of powder metallurgy (PM) alloys for various applications was produced on the base of water atomised powders. The characteristics of tensile strength of such alloys essentially exceed those of cast materials of similar compositions.

  13. Water atomised aluminium alloy powders

    International Nuclear Information System (INIS)

    The new rapid solidification (RS) process based on high-pressure water atomisation (WA) of the melt for manufacturing of advanced aluminium alloys was realised in the form of a pilot plant. The problems of safe operation in the course of Al alloy powder production and powder quality were solved by the use of water solutions of inhibitors, by the control of suspension temperature and hydrogen ion exponent (pH), by the hydraulic classification of atomised products, and by the optimisation of dehydration procedure. The rate of powder-water interaction strongly depends on the value of pH. While the rate of room temperature reactions is very slow at pH 3.0-4.0, the increase of pH to 6.0 leads to an intensive powder oxidation. A set of powder metallurgy (PM) alloys for various applications was produced on the base of water atomised powders. The characteristics of tensile strength of such alloys essentially exceed those of cast materials of similar compositions

  14. Increasing world demand for primary aluminium in the current decade: An encumbrance for environment? - A partial equilibrium analysis

    Energy Technology Data Exchange (ETDEWEB)

    Poganietz, W.R. [Forschungszentrum Juelich (Germany). Systemforschung und Technologische Entwicklung

    2001-07-01

    Aluminium is in the manufacturing and consumer industry a very popular light metal. The prevalence of aluminium is due to its mineralogical and chemical characteristics. The objective of the paper is to discuss, whether an increase in worldwide demand for primary aluminium is a growing burden for environment. Primary aluminium processing is by its nature energy and resource intensive and thus, potentially, high polluting. The paper focuses on emissions of carbon dioxide and the per fluorocarbons (PFCs) CF4 and C2H6. The analysis is made by using the model GlobAl, a partial equilibrium world aluminium trade model. It depicts the material flow of primary aluminium processing. Estimating rising demand for primary aluminium, reaching in 2010 25m t, 28m t and 31m t, resp, compared to 20m t in 1995, production of bauxite, alumina, and primary aluminium will increase. Growing production requires rising energy input in the material flow. However, declining specific energy consumption offsets only in low demand scenario this trend completely. Total emissions of considered greenhouse gases, which are influenced by energy use, would fall in two of three scenarios. Only in case of high demand, additional production of primary aluminium and thus extra emissions are not offset by the drastic decline of specific emissions. The drop of specific emissions is mainly due to a decline of PFCs gaseous emissions, which occur only in electrolysis. Looking at smelters as main issuer of CO2, the drop of specific emissions in all three cases is mainly due to higher efficiency of power generation and energy use in the smelting process. Irrespective of that, the emission level of CO2 during electrolyse will reach in 2010 nearly the lowest possible one using the currently known state of the art technology as a reference point. This will not be the case regarding PFCs emissions.

  15. Aluminium as heating fuel. Tests with aluminium powder prove suitability in principle. Aluminium als Heizungs-Brennstoff. Versuche mit Aluminiumpulver beweisen prinzipielle Eignung

    Energy Technology Data Exchange (ETDEWEB)

    Weber, R.

    1990-12-01

    Tests prove that aluminium powder is perfectly suited as fuel and storage material for solar energy. The combustion product itself is again the base material for aluminium production, i.e. aluminium can be recycled. There are three problematic areas: 1. flame stability, 2. combustion duration and 3. environmental compatibility. Further development projects will aim at the construction of practice-orientated plants in which combustion, heat extraction and recovery of aluminium oxide is combined. A further aim is the melting burner to which aluminium is supplied in form of wires, cuttings or rods. (BWI).

  16. Spectrum Simulation of Li-Like Aluminium Plasma

    Institute of Scientific and Technical Information of China (English)

    PENG Feng; JIANG Gang; ZHU Zheng-He

    2006-01-01

    X-ray emission spectra for L-shell of Li-like aluminium ions are simulated by using the flexible atomic code based on the collisional radiative model. Atomic processes including radiative recombination, dielectronic recombination, collisional ionization and resonance excitation from the neighbouring ion (Al9+ and Al11+) charge states of the target ion (Al10+) are considered in the model. In addition, the contributions of different atomic processes to the x-ray spectrum are analysed. The results show that dielectronic recombination, radiative recombination, collisional ionization and resonance excitation, other than direct collisional excitation, are very important processes.

  17. 3-dimensional shaped aluminium foam sandwiches

    Energy Technology Data Exchange (ETDEWEB)

    Baumeister, J. [Fraunhofer-Institut fuer Fertigungstechnik und Angewandte Materialforschung, Bremen (Germany); Baumgaertner, F. [Schunk Sintermetalltechnik, Giessen (Germany); Gers, H. [Honsel AG, Meschede (Germany); Seeliger, W. [Wilhelm Karmann GmbH, Osnabrueck (Germany)

    2000-07-01

    3-dimensional shaped sandwich panels with a very high stiffness can be produced in an elegant way by combining aluminium face sheets with an aluminium foam core. For this, a mixture of aluminium powder and a foaming agent is compressed to a semi-finished product of nearly vanishing porosity by extrusion, powder rolling or hot isostatic pressing. The resulting foamable semi-finished aluminium material is roll clad with sheets of conventional sheet or aluminium. As a result a precursor material is obtained consisting of two face sheets which are metallurgically bonded to the foamable core layer. This sandwich precursor material can be shaped into a 3-dimensional part by conventional techniques, e.g. by stamping or deep drawing. In a final step the foamable precursor material is heated up to the melting point of the core layer thus initiating its expansion into the desired 3-dimensional shaped sandwich structure. The porosity of the foamed core layer is in the range from 80-90% so that the integral density of the sandwich structure can be as low as 0,7 g/cm{sup 3}. The sandwich materials combine the low weight and high bending stiffness with the advantages of the face sheets, i.e. the high strength and weldability. The manufacturing process will be described in detail and the material properties will be shown. Current and future possible applications will be outlined as well as concrete parts produced up to date. (orig.)

  18. Effect of aluminium phosphate as admixture on oxychloride cement

    Indian Academy of Sciences (India)

    M P S Chandrawat; R N Yadav

    2000-02-01

    The effect of admixing of aluminium phosphate on oxychloride cement in the matrix has been investigated. It is shown that aluminium phosphate retards the setting process of the cement and improves water-tightness.

  19. Solidification of spent TBP solvent with aluminium chloride compounds

    International Nuclear Information System (INIS)

    The new techniques for processing spent TBP was investigated. It was proved that treatment of TBP containing DBP with aluminium chloride resulted in the formation of aluminium phosphate suitable for long term storage and final disposal

  20. A study of boron determination in high purity aluminium by capture gamma-ray measurement

    International Nuclear Information System (INIS)

    The boron content in reactor grade aluminium has been determined by means of a capture gamma-ray counting method. The experimental detection limit is found to be 5.7 ppm with 10% uncertainty. In order to improve the sensitivity, the boron is preconcentrated from aluminium by cation exchange resin system. The accuracies of both methods, i.e., one by the direct measurement and the other by the measurement after preconcentration, are checked by an additive method. The results show good agreements with less than 5% deviation. (author)

  1. Effect of Alloying Elements to Aluminium on the Wettability of AL/SiC System

    OpenAIRE

    CANDAN, Ercan

    2002-01-01

    The wettability at a liquid Al-alloy/SiC interface was evaluated by the sessile drop method at 750oC. The wetting angle, q ,of a sessile drop on SiC substrate decreased with the addition of Pb, Mg and Ca to pure aluminium. The reduction in q of the Al-Pb alloy was proportional to the reduction in surface tension, glv, of aluminium, whereas in Al-Mg and Al-Ca alloys the reduction in q was greater than the reduction in g lv of Al. This was attributed to reactions that took place at the Al-all...

  2. The study of aluminium anodes for high power density AL-air batteries with brine electrolytes

    OpenAIRE

    Nestoridi, Maria

    2009-01-01

    In this thesis aluminium alloys containing small additions of both tin (~ 0.1 wt %) and gallium (~ 0.05 wt %) dissolve anodically at high rates in brine media; at room temperature, current densities > 0.2 A cm-2 can be obtained at potentials close to the open circuit potential, ~ -1.5 V vs SCE. Alloys without both tin and gallium do not dissolve at such a negative potential. The tin exists in the alloys as a second phase, typically as ~ 1 ?m inclusions throughout the aluminium structure. Anod...

  3. Bioactive type glass-ceramics within incorporated aluminium; Vitroceramicos del tipo bioactivo con aluminio incorporado

    Energy Technology Data Exchange (ETDEWEB)

    Volzone, C.; Stabile, F.M.; Ortiga, J., E-mail: volzcris@netverk.com.ar [Centro de Tecnologia de Recursos Minerales y Ceramica (CETMIC), Buenos Aires (Argentina)

    2012-07-01

    Bioactive glass-ceramics are used as biomaterials for the reparation of bone tissue. They are prepared, generally, by bioglass of specific composition for each particular use. The aluminium addition in the formulation at very small quantities influences on the structural properties. Two glass-ceramics obtained by P{sub 2}O{sub 5}-Na{sub 2}O-CaO-SiO{sub 2} formulation within aluminium (0.5 % in Al{sub 2}O{sub 3} base) added through a reactive alumina and purified feldspar were analyzed. The results showed structural differences between both glass-ceramics. (author)

  4. Steam Assisted Accelerated Growth of Oxide Layer on Aluminium Alloys

    DEFF Research Database (Denmark)

    Din, Rameez Ud; Yuksel, Serkan; Jellesen, Morten Stendahl; Møller, Per; Ambat, Rajan

    2013-01-01

    Corrosion resistance of aluminium alloys is related to the composition and morphology of the oxide film on the surface of aluminium. In this paper we investigated the use of steam on the surface modification of aluminium to produce boehmite films. The study reveals a detailed investigation of the...... effect of vapour pressure, structure of intermetallic particles and thickness of boehmite films on the corrosion behaviour of aluminium alloys....

  5. Advances in development and application of aluminium batteries

    DEFF Research Database (Denmark)

    Qingfeng, Li; Zhuxian, Qiu

    2001-01-01

    Aluminium has long attracted attention as a potential battery anode because of its high theoretical voltage and specific energy. The protective oxide layer at aluminium surface is however detrimental to its performance to achieve its reversible potential, and also causing the delayed activation of...... aluminium batteres, especially aluminium-air batteries, and a wide range of their applications from emergency power supplies, reserve batteries field portable batteries, to batteries for electric vehicles and underwater propulsion....

  6. Friction stir welding (FSW) of aluminium foam sandwich panels

    OpenAIRE

    M. Bušić; Kožuh, Z.; D. Klobčar; Samardžić, I.

    2016-01-01

    The article focuses on the influence of welding speed and tool tilt angle upon the mechanical properties at the friction stir welding of aluminium foam sandwich panels. Double side welding was used for producing butt welds of aluminium sandwich panels applying insertion of extruded aluminium profile. Such insertion provided lower pressure of the tool upon the aluminium panels, providing also sufficient volume of the material required for the weldment formation. Ultimate tensile strength and f...

  7. Effect of iron present in commercial aluminium sulphate on its water coagulation properties

    International Nuclear Information System (INIS)

    The efficiency of aluminium sulphate obtained from venezuelan bauxite as coagulant for water treatment was studied. The results show an average 15% aluminium content expressed as Al2O3 and 1.4% iron content as Fe2O3. The efficiency was similar to that of an iron free analytical grade aluminium sulphate. The significant content of iron found means an additional component that can participate in the coagulation flocculation process; hence the known coagulation properties of iron as a metallic coagulant. The results obtained confirm the iron role in the process and further research, using higher iron contents in the order of 2 percent and more, are proposed to obtain a quantitative evaluation of the participation of this element in the coagulation process. The results can contribute to evaluate the current regulations concerning quality control of the product for use in drinking water

  8. Mechanical characteristics of aluminium / aluminium and aluminium / steel joints used for lightening of automobile bodies; Caracteristiques mecaniques d'assemblages aluminium / aluminium et aluminium / acier utilises pour l'allegement des carrosseries automobiles

    Energy Technology Data Exchange (ETDEWEB)

    Kosuge, Haraga [Mitsubishi Electric Corp., Centre de R and D des Technologies Avancees, Dept. des Materiaux et des Eco-Materiaux (Japan)

    2001-06-01

    All the possible solutions used for the steel-aluminium composite bonds are not equal. The riveting, linked or not to the bonding, give the best results. The clinching requires an increase of thicknesses for a mechanical resistance equal to those of homogeneous joints. (O.M.)

  9. Corrosion behaviour of borated aluminium used as neutron absorber

    International Nuclear Information System (INIS)

    The electrochemical behaviour of pure and borated aluminium was examined. Measurements were performed in two different electrolytes at 90 C containing different trace-amounts of chloride. For borated aluminium current transients, i.e. metastable depassivation events were found. It is suggested to attribute these transients to less stable passivation layers in comparison to pure aluminium

  10. Corrosion of Metal-Matrix Composites with Aluminium Alloy Substrate

    OpenAIRE

    B. Bobic; Mitrovic, S.; M. Babic; I. Bobic

    2010-01-01

    The corrosion behaviour of MMCs with aluminium alloy matrix was presented. The corrosion characteristics of boron-, graphite-, silicon carbide-, alumina- and mica- reinforced aluminium MMCs were reviewed. The reinforcing phase influence on MMCs corrosion rate as well as on various corrosion forms (galvanic, pitting, stress corrosion cracking, corrosion fatique, tribocorrosion) was discussed. Some corrosion protection methods of aluminium based MMCs were described

  11. Internal friction in iron-aluminium alloys having a high aluminium content

    International Nuclear Information System (INIS)

    By using a torsion pendulum to measure the internal friction of iron-aluminium alloys containing between 25 and 50 atom per cent of aluminium, it has been possible to show the existence of three damping peaks due to interstitial carbon. Their evolution is followed as a function of the carbon content, of the thermal treatment and of the aluminium content. A model based on the preferential occupation of tetrahedral sites is proposed as an interpretation of the results. A study of the Zener peak in these substitution alloys shows also that a part of the short distance disorder existing at high temperatures can be preserved by quenching. (author)

  12. Diamond grooving of rapidly solidified optical aluminium

    Science.gov (United States)

    Abou-El-Hossein, Khaled; Hsu, Wei-Yao; Ghobashy, Sameh; Cheng, Yuan-Chieh; Mkoko, Zwelinzima

    2015-10-01

    Traditional optical aluminium grades such as Al 6061 are intensively used for making optical components for applications ranging from mould insert fabrication to laser machine making. However, because of their irregular microstructure and relative inhomogeneity of material properties at micro scale, traditional optical aluminium may exhibit some difficulties when ultra-high precision diamond turned. Inhomogeneity and micro-variation in the material properties combined with uneven and coarse microstructure may cause unacceptable surface finish and accelerated tool wear, especially in grooving operation when the diamond tool edge is fully immersed in the material surface. Recently, new grades of optical aluminium that are featured by their ultra-fine microstructure and improved material properties have been developed to overcome the problem of high tool wear rates. The new aluminium grades have been developed using rapid solidification process which results in extremely small grain sizes combined with improved mechanical properties. The current study is concerned with investigating the performance of single-point diamond turning when grooving two grades of rapidly solidified aluminium (RSA) grades: RSA905 which is a high-alloyed aluminium grade and RSA443 which has a high silicon content. In this study, two series of experiments employed to create radial microgrooves on the two RSA grades. The surface roughness obtained on the groove surface is measured when different combinations of cutting parameters are used. Cutting speed is varied while feed rate and depth of cut were kept constant. The results show that groove surface roughness produced on RSA443 is higher than that obtained on RSA905. Also, the paper reports on the effect of cutting speed on surface roughness for each RSA grade.

  13. Carbon respiration and nitrogen dynamics in Corsican pine litter amended with aluminium and tannins

    NARCIS (Netherlands)

    P. Kraal; K.G.J. Nierop; J. Kaal; A. Tietema

    2009-01-01

    We investigated the carbon (C) mineralisation and nitrogen (N) dynamics in litter from a Corsican pine forest in response to individual and combined additions of aluminium (M), condensed tannin (extracted from fresh Corsican pine needles) and hydrolysable tannin (commercial tannic acid). Production

  14. Defect generation during solidification of aluminium foams

    International Nuclear Information System (INIS)

    The reason for the frequent occurrence of cell wall defects in metal foams was investigated. Aluminium foams often expand during solidification, a process which is referred as solidification expansion (SE). The effect of SE on the structure of aluminium foams was studied in situ by X-ray radioscopy and ex situ by X-ray tomography. A direct correlation between the magnitude of SE and the number of cell wall ruptures during SE and finally the number of defects in the solidified foams was found.

  15. The dissolution and formation enthalpy of alloys and intermetallics of aluminium-lanthanum and aluminium-cerium systems

    International Nuclear Information System (INIS)

    Present article is devoted to dissolution and formation enthalpy of alloys and intermetallics of aluminium-lanthanum and aluminium-cerium systems. Therefore the dissolution temperatures of alloys and intermetallics of aluminium-lanthanum and aluminium-cerium systems were defined by means of calorimetry method. The enthalpy of formation of intermetallics of Al-Ce system was defined as well. The regularities in changes of dissolution and formation enthalpy of alloys and intermetallics depending on composition were studied.

  16. China’s Production and Market of Aluminium Extruded Profiles

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    <正>Chinese aluminium extrusion industry came into existence at the early 1950s with most products used in military industry and national defence.At the beginning of 1980s,the produc- tion of construction aluminium profiles started simultaneously in North and South China.In the following thirty years,the aluminium extru- sion industry entered into a quickly developing stage with a focus on construction aluminium profiles.With the blooming real estate industry, the demand for construction aluminium profiles from the domestic market has a tendency of yearly increase.From 2000,the quick devel- opments of China’s auto and railway vehicle

  17. Aluminium composite casting dispersion reinforced with iron-aluminium and silicon carbide phases

    OpenAIRE

    B. Formanek; J. Piątkowski; J. Szymszal

    2010-01-01

    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 parameter...

  18. Influence of aluminium alloy type on dissimilar friction stir lap welding of aluminium to copper

    OpenAIRE

    Galvão, I; Verdera, D; Gesto, D; Loureiro, A.; Rodrigues, D. M.

    2013-01-01

    A heat-treatable (AA 6082) and a non-heat treatable (AA 5083) aluminium alloys were friction stir lap welded to copper using the same welding parameters. Macro and microscopic analysis of the welds enabled to detect important differences in welding results, according to the aluminium alloy type. Whereas important internal defects, resulting from ineffective materials mixing, were detected for the AA 5083/copper welds, a relatively uniform material mixing was detected in the AA 6082/copper wel...

  19. Decreasing methylation of pectin caused by nitric oxide leads to higher aluminium binding in cell walls and greater aluminium sensitivity of wheat roots

    OpenAIRE

    Sun, Chengliang; Lu, Lingli; Yu, Yan; Liu, Lijuan; Hu, Yan; Ye, Yiquan; Jin, Chongwei; Lin, Xianyong

    2015-01-01

    Highlight Aluminium-induced nitric oxide production enhances the aluminium sensitivity of wheat by decreasing pectin methylation of root cell-wall pectin, resulting in greater aluminium binding in root cell walls.

  20. Steam generated conversion coating on aluminium alloys

    DEFF Research Database (Denmark)

    Din, Rameez Ud; Jellesen, Morten Stendahl; Ambat, Rajan

    into functional conversion coatings in order to enhance corrosion resistance and adhesion to paint systems. Chromium based conversion coatings have been extensively used on aluminium alloys to improve adhesion of subsequent paint layers and corrosion resistance. However, the use of hexavalent chromium...

  1. Alloys oxidation of aluminium-scandium system

    International Nuclear Information System (INIS)

    Alloys and compounds of rare earth metals with aluminium thanks to their high corrosion stability, durability and small specific weight find to apply in various new techniques. On the base of carried out investigation it could be recommend as de oxidizing and alloying compositions containing 15-50 % of scandium as in possession of minimal oxidation

  2. Constant structure creep experiments on aluminium

    Czech Academy of Sciences Publication Activity Database

    Milička, Karel

    2011-01-01

    Roč. 49, č. 5 (2011), s. 307-318. ISSN 0023-432X R&D Projects: GA AV ČR IAA2041203 Institutional research plan: CEZ:AV0Z20410507 Keywords : mechanical properties * high temperature deformation * creep * aluminium Subject RIV: BM - Solid Matter Physics ; Magnetism Impact factor: 0.451, year: 2011

  3. An ultrafast rechargeable aluminium-ion battery

    Science.gov (United States)

    Lin, Meng-Chang; Gong, Ming; Lu, Bingan; Wu, Yingpeng; Wang, Di-Yan; Guan, Mingyun; Angell, Michael; Chen, Changxin; Yang, Jiang; Hwang, Bing-Joe; Dai, Hongjie

    2015-04-01

    The development of new rechargeable battery systems could fuel various energy applications, from personal electronics to grid storage. Rechargeable aluminium-based batteries offer the possibilities of low cost and low flammability, together with three-electron-redox properties leading to high capacity. However, research efforts over the past 30 years have encountered numerous problems, such as cathode material disintegration, low cell discharge voltage (about 0.55 volts ref. 5), capacitive behaviour without discharge voltage plateaus (1.1-0.2 volts or 1.8-0.8 volts) and insufficient cycle life (less than 100 cycles) with rapid capacity decay (by 26-85 per cent over 100 cycles). Here we present a rechargeable aluminium battery with high-rate capability that uses an aluminium metal anode and a three-dimensional graphitic-foam cathode. The battery operates through the electrochemical deposition and dissolution of aluminium at the anode, and intercalation/de-intercalation of chloroaluminate anions in the graphite, using a non-flammable ionic liquid electrolyte. The cell exhibits well-defined discharge voltage plateaus near 2 volts, a specific capacity of about 70 mA h g-1 and a Coulombic efficiency of approximately 98 per cent. The cathode was found to enable fast anion diffusion and intercalation, affording charging times of around one minute with a current density of ~4,000 mA g-1 (equivalent to ~3,000 W kg-1), and to withstand more than 7,500 cycles without capacity decay.

  4. Aluminium hydroxide-induced granulomas in pigs

    DEFF Research Database (Denmark)

    Valtulini, S; Macchi, C; Ballanti, P;

    2005-01-01

    adjuvant) to pigs inoculated twice with apyrogenic bi-distilled water (group water) and to pigs inoculated once with the adjuvant and once with apyrogenic bi-distilled water (group adjuvant/water). Both studies agreed in their conclusions, which indicate that the high amount of aluminium hydroxide was the...

  5. Indentation of aluminium foam at low velocity

    Directory of Open Access Journals (Sweden)

    Shi Xiaopeng

    2015-01-01

    Full Text Available The indentation behaviour of aluminium foams at low velocity (10 m/s ∼ 30 m/s was investigated both in experiments and numerical simulation in this paper. A flat-ended indenter was used and the force-displacement history was recorded. The Split Hopkinson Pressure bar was used to obtain the indentation velocity and forces in the dynamic experiments. Because of the low strength of the aluminium foam, PMMA bar was used, and the experimental data were corrected using Bacon's method. The energy absorption characteristics varying with impact velocity were then obtained. It was found that the energy absorption ability of aluminium foam gradually increases in the quasi-static regime and shows a significant increase at ∼10 m/s velocity. Numerical simulation was also conducted to investigate this process. A 3D Voronoi model was used and models with different relative densities were investigated as well as those with different failure strain. The indentation energy increases with both the relative density and failure strain. The analysis of the FE model implies that the significant change in energy absorption ability of aluminium foam in indentation at ∼10 m/s velocity may be caused by plastic wave effect.

  6. Reactive sputter deposition of Al doped TiOx thin films using titanium targets with aluminium inserts

    International Nuclear Information System (INIS)

    Highlights: •Ti(Al)Ox thin films with varying Al fractions and increasing discharge current were deposited. •The reactive sputtering behaviour of Ti targets with Al inserts was studied. •XPS and EDX were used to check the stoichiometry of the films. •Optical transmittance measurements were performed to determine the band gap. -- Abstract: Al doped TiOx thin films were deposited using Ti targets with Al inserts. Both the effect of the number of aluminium inserts and the discharge current on the discharge voltage, on the aluminium content in the thin films, and on the reactive sputtering behaviour was investigated. The aluminium content in the film was measured using X-ray photoelectron spectroscopy (XPS) and energy-dispersive X-ray spectroscopy (EDX). X-ray diffraction (XRD) revealed that the as-deposited thin films were amorphous, independent of the aluminium content or the discharge current. The XPS results indicated that the oxide films were substoichiometric. The optical band gap of the Ti(Al)Ox thin films was investigated as a function of the aluminium concentration and the discharge current. The addition of aluminium results in a significant increase of the band gap at low discharge currents, while no significant influence on the band gap was found at higher currents

  7. Characterisation of the bonding zone of co-extruded aluminium-titanium-compounds

    Energy Technology Data Exchange (ETDEWEB)

    Grittner, N.; Schaper, M.; Bach, F.W. [Institut fuer Werkstoffkunde, Garbsen (Germany); Hehl, A. von; Hunkel, M.; Schimanski, K.; Zoch, H.W. [Stiftung Institut fuer Werkstofftechnik, Bremen (Germany); Stelling, O. [Parker Hannifin Manufacturing GmbH and Co. KG, Stuhr (Germany); Striewe, B.

    2012-04-15

    The combination of different metallic materials enables the design of lightweight structures with tailor-made properties at global as well as local scale and offers great potential for advanced solutions especially for the aircraft and automobile sector. However, after conventional fusion joining, e. g. after laser beam welding, heat affected zones, porosity or grain growth may occur and impair the local properties. In contrast, by solid-state joining techniques like co-extrusion these disadvantages can be avoided. Therefore co-extrusion exhibits an attractive solution for long products combining aluminium and titanium based alloys. Current investigations have been focused on the co-extrusion of aluminium and titanium, where titanium is the reinforcing element that is inserted in aluminium profiles. In the context of a current research project the formation of the intermetallic layer and the mechanical properties were investigated in detail. In addition to that the influence on the intermetallic layer and the mechanical properties on heat treatment were investigated. The mechanical properties were determined by tensile tests. The intermetallic layers were analysed with light optical microscope, scanning electron microscope and electron probe micro analysis. During the co-extruding an intermetallic layer with a thickness of 1 {mu}m to 3 {mu}m arises in the bonding zone between aluminium and titanium partner. Alloying elements from the aluminium alloy enrich in this layer. A subsequent heat treatment leads to an age hardening of the aluminium, however, it does not affect the layer thickness. The tensile tests specimen show different failure locations. The heat treatment leads to increased tensile strength values, but also to a decreased yield strength level. (Copyright copyright 2012 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)

  8. Technology of obtaining of cryolite and aluminium fluoride from alumina- and fluoride containing wastes of aluminium production

    International Nuclear Information System (INIS)

    This article is devoted to technology of obtaining of cryolite and aluminium fluoride from alumina- and fluoride containing wastes of aluminium production. Thus, the investigations on elaboration of technology of obtaining of cryolite and aluminium fluoride from alumina- and fluoride containing wastes of aluminium production by means of sulfuric acid decomposition method are carried out. The optimal parameters of technological processes are found. The physicochemical analysis of fluoride containing wastes is conducted. The flowsheet of obtaining of cryolite, aluminium fluoride and alumina from alumina- and fluoride containing wastes is presented.

  9. ThermophysicalProperties of Cellular Aluminium andCeramic Particulate / Aluminium Composites

    Directory of Open Access Journals (Sweden)

    Khalid Almadhoni

    2015-10-01

    Full Text Available In this paper, the thermophysical properties of cellular Al and Ceramic Particulate / Al Composites were explored. Thermophysical properties are defined as material properties that vary with temperature without altering the material's chemical identity including thermal conductivity (TC, coefficient of thermal expansion (CTE, energy absorption, porosity and relative density. The significance of cellular Al and AMMCs reinforced by ceramic particles lies in their propertieswhich are difficult to be available combined in other engineering materials. New cellular AMMCs that meet the needs of the required engineering applications could be synthesized by selection an appropriate reinforcements. Different kinds of ceramic particles such as oxides, carbides, nitrides, as well as carbon nanotubes can be utilized as reinforcements for manufacturing of cellular AMMCs. Thermophysicalproperties of cellular AMMCs consisting of Al as continuous matrix phase and ceramic particles as reinforcements are directly influenced by type, size, and geometry of dispersions, also the RVR. In addition, the constituents of ceramic particulate / aluminium composites characterized by different heat transfer mechanisms, wherethe TC mechanism in metals is attributed to free electrons, while phonons are primarily responsible for TC in nonmetallic materials, as well as an interfacial thermal barrier resistance influence effectively on heat transfer inside the composite and thus the thermophysical properties. In this paper, based on the literature review, thermophysical properties of cellular Al and AMMCs reinforced by ceramic particles were discussed.

  10. Solidification and precipitation in aluminium-zirconium alloys. Pt. 1

    International Nuclear Information System (INIS)

    The cast structure and the precipitating primary phases were investigated in Al-Zr alloys on the basis of high-purity Aluminium with 0.1 to 1.2 wt.% Zr after fast solidification in a watercooled mold. With higher Zr-saturation of the melt the tetragonal ZrAl3-equilibrium phase appears, which is already known from slowly cooled samples. In alloys with lower Zr-supersaturation with respect to the raised Zr-solubility of about 0.6 wt.% due to the fast solidification there appears solely or additionally the new metastable cubic ZrAl3-phase as the primary precipitation. The particles show cubic or fourfold symmetric star form and have nearly the same lattice parameters as Aluminium. By coherent epitaxi of the Al-lattice they act as prefered nuclei for the solidification of the α-phase. Consequently an intensive grain refining takes place in a critical concentration range depending on temperature of pouring and cooling rate. (orig.)

  11. Steam Initiated Surface Modification of Aluminium Alloys

    DEFF Research Database (Denmark)

    Din, Rameez Ud

    detailed analysis of the structure and morphology of the coating, and interface structure with and without organic top coat. Corrosion performance of the coatings was investigated using electrochemical methods, AASS, and FFC test. The morphology, microstructure, chemical composition, adhesion, and......The extensive demand of aluminium alloys in various industries such as in transportationis mainly due to the high strength to weight ratio, which could be translated into fuel economy and efficiency. Corrosion protection of aluminium alloys is an important aspect for all applications which includes......-friendly alternative processes. In the present work high temperature steam-based process has been investigated as a possible chromate free conversion coating. Investigations in the thesis includes the effect of alloy type, substrate microstructure, surface finish, and various chemistries on the coating formation, and...

  12. Studies on an aluminium-carbon cell

    Science.gov (United States)

    Verma, L. K.

    The current-voltage behaviour of an electrochemical cell that consists of an aluminium anode and a carbon cathode in a medium containing aqueous NH 4SCN has been studied, both in the presence and in the absence of a coating on the carbon electrode. It is found that activation polarization is the main factor that limits the current output when using an untreated carbon electrode. This problem is eliminated by coating the carbon electrode with an in situ deposition of HgI 2. In this condition, the current output is reduced mainly by ohmic polarization. Further studies with a coated HgI 2-carbon cathode and an aluminium anode, in a medium containing SCN - and Cl - ions together with a complexing agent (EDTA, sodium salt), revealed that a cell performance close to ideal, (i.e, showing no appreciable polarization) can be obtained at currents up to 0.6 mA/cm 2 and above.

  13. Straggling of heavy ions in aluminium

    International Nuclear Information System (INIS)

    An effort has been made to determine the straggling in aluminium of 4He, 16O and 35Cl ions of different energies produced by the tandem Van de Graaff at Harwell. The technique consists of scattering the accelerated and collimated ions in a scattering chamber from a 0.100 mg/cm2 gold foil, allowing the scattered ions to pass through a two aperture collimator, using different aluminium foils over one of the apertures and stopping the two emergent beams in a good quality silicon surface barrier detector the output of which is connected to a 4096 channel analyser. The energy widths obtained in the case of helium ions are in fair agreement with both the Bloch and the recent Tschalar (1968) theory. The measured widths in the case of heavy ions are very large and can be explained only if account is taken of their charge distributions in foils. This study should be useful in ion implantation work. (author)

  14. Alkali-Activated Aluminium-Silicate Composites as Insulation Materials for Industrial Application

    Science.gov (United States)

    Dembovska, L.; Bajare, D.; Pundiene, I.; Bumanis, G.

    2015-11-01

    The article reports on the study of thermal stability of alkali-activated aluminium- silicate composites (ASC) at temperature 800-1100°C. ASC were prepared by using calcined kaolinite clay, aluminium scrap recycling waste, lead-silicate glass waste and quartz sand. As alkali activator, commercial sodium silicate solution modified with an addition of sodium hydroxide was used. The obtained alkali activation solution had silica modulus Ms=1.67. Components of aluminium scrap recycling waste (aluminium nitride (AlN) and iron sulphite (FeSO3)) react in the alkali media and create gases - ammonia and sulphur dioxide, which provide the porous structure of the material [1]. Changes in the chemical composition of ASC during heating were identified and quantitatively analysed by using DTA/TG, dimension changes during the heating process were determined by using HTOM, pore microstructure was examined by SEM, and mineralogical composition of ASC was determined by XRD. The density of ASC was measured in accordance with EN 1097-7. ASC with density around 560 kg/m3 and heat resistance up to 1100°C with shrinkage less than 5% were obtained. The intended use of this material is the application as an insulation material for industrial purposes at elevated temperatures.

  15. Fundamental studies of growth mechanisms in physical vapour deposition of aluminium

    CERN Document Server

    Knorr, N J

    2000-01-01

    temperature could be independently controlled due to the low deposition rate of the aluminium. The depositions were performed in a UHV environment to ensure that film growth was not mediated by contamination. The ion energy range used was 10-75eV and the substrate temperature varied from -100 deg C to 200 deg C. The depositions were onto silicon (100) with a native oxide surface, except for a set of depositions which were performed on to silicon with the native oxide surface removed. The cleanliness of the depositions was verified using in-situ XPS analysis and after deposition the structure of the aluminium films was inferred from measurements using SEM, TEM, AFM XRD and Nano-indendation. This information allowed the mechanisms of growth of the aluminium films to be investigated. In addition to the extensive array of IBDR depositions a series of aluminium films were deposited using evaporation and sputtering. These films were grown at substrate temperatures between room temperate and 200 deg C. The use of ev...

  16. Aluminium-based Coatings for Cadmium Replacement

    OpenAIRE

    Cardilli , Emanuele

    2008-01-01

    Cadmium electroplating is widely used in the aerospace industry for the corrosion protection of high strength steels. Cadmium is also used as compatible coating to reduce the galvanic corrosion generated in the assembly of components manufactured with different materials. However, environmental and safety concerns over the high toxicity of cadmium has led to the investigation of suitable replacements. Aluminium coatings are promising coatings for the replacement of electropl...

  17. Aluminium matrix composites fabricated by infiltration method

    OpenAIRE

    L.A. Dobrzański; M. Kremzer; A. J. Nowak; Nagel, A.

    2009-01-01

    Purpose: The aim of this work is to examine the structure and properties of metal matrix composites obtained by infiltration method of porous ceramic preforms by liquid aluminium alloy.Design/methodology/approach: Ceramic preforms were manufactured by the sintering method of ceramic powder. The preform material consists of powder Condea Al2O3 CL 2500, however, as the pore forming the carbon fibers Sigrafil C10 M250 UNS were used. Then ceramic preforms were infiltrated with liquid eutectic EN ...

  18. Methods of inoculation of pure aluminium structure

    Directory of Open Access Journals (Sweden)

    J. Szajnar

    2008-03-01

    Full Text Available Purpose: The main aim of investigations was the reduction of grain size and unification of structure for pure Al casting by introduction of small amount of inoculant (less than obligatory standart PN-EN 573-3, which concerning about aluminium purity, with electromagnetic field and variable casting parameters.Design/methodology/approach: To investigations it was used light microscopy and TEM. Surfaces of samples which were prepared for macro- and microstructure analysis were etched with use of solution of: 50g Cu, 400ml HCl, 300ml HNO3 and 300ml H2O. Thin foils for TEM investigations were electropolished with use of 20 ml HClO4 and 80ml CH3OH.Findings: The results of investigations and their analysis show possibility of effective inoculation of pure aluminium structure by use of some factors such as: different materials of the mould, influencing of stirring electromagnetic field into metal during solidification, inoculation by introducing AlTi5B1 inoculant into liquid aluminium and changing the pouring temperature.Research limitations/implications: I further research, authors of this paper are going to application of introduced method of inoculation in industrial tests.Practical implications: The work presents refinement of structure method which are particularly important in continuous and semi – continuous casting where products are used for plastic forming. Large columnar crystals zone result in forces extrusion rate reduction and during the ingot rolling delamination of external layers can occur. Thus, in some cases ingot skinning is needed, which rises the production costs.Originality/value: Contributes to research on size reduction in pure aluminium structure.

  19. Perforation of aluminium alloy thin plates

    OpenAIRE

    ANTOINAT, Léonard; Kubler, Régis; BAROU, Jean Luc; VIOT, Philippe; BARRALLIER, Laurent

    2015-01-01

    Low velocity perforation of aeronautical aluminium alloy sheets 2024 T3 is studied in this paper. After a literature review on recent experiments and models of plate’s perforation, experimental results for 2 thicknesses (2 mm and 4 mm) of plates are presented. Perforation tests are performed with an instrumented drop test. The striker has a large diameter and a conical shape nose. Two models for perforation are presented and calibrated to bring a better understanding of the experiments. The f...

  20. Aluminium phosphide poising: a case report

    International Nuclear Information System (INIS)

    This paper reports the case of a family in which three children were presented at Emergency Room (ER) with poisoning after the use of a pesticide at home. Initially, the cases were managed as routine cases of organophosphorus poisoning; however, the death of two children made the health team members realise that the poison's effects were delayed and devastating. Later, the compound was identified as Aluminium Phosphide (ALP), and the life of the last surviving child in the family was saved. (author)

  1. Ion beam analysis of aluminium in thin layers

    Energy Technology Data Exchange (ETDEWEB)

    Healy, M.J.F. E-mail: m.j.f.healy@rmcs.cranfield.ac.uk; Pidduck, A.J.; Dollinger, G.; Gorgens, L.; Bergmaier, A

    2002-05-01

    This work quantifies aluminium in thin surface and near surface layers. In one example, the layer overlies a thin gallium nitride layer on an aluminium oxide substrate and in a second example the aluminium exists just below the surface of an indium arsenide substrate. The technique of non-Rutherford elastic backscattering of protons was used for the samples where aluminum in the layer of interest needed to be resolved from aluminium in the sapphire substrate and the results were corroborated at the Technische Universitaet Muenchen using heavy ion elastic recoil detection analysis. In the second example, where it was unnecessary to isolate the signal of aluminium in the layer of interest (as the substrate contained no aluminium), then the {sup 27}Al(d,p{sub 01}){sup 28} Al nuclear reaction was used. The elastic proton scattering cross section of aluminum was found to vary very rapidly over the energy range of interest.

  2. First wall design of aluminium alloy R-tokamak

    International Nuclear Information System (INIS)

    A design study of a low-activation D-T tokamak Reacting Plasma Project In Nagoya has been finished. The study emphasizes the vacuum vessel and the bumper limiter. Our choice of materials (aluminium vacuum vessel, copper conductors, aluminium TF coil case and lead shield) results in a radiation level of about 1 x 10-3 times that of a TFTR type design, and 1 x 10-4 times that of JET type design, at 2 weeks after one D-T shot. Thick graphite tiles will be fixed directly on the aluminium vacuum vessel using aluminium spring washers and bolts. With this simplified structure of the bumper limiter, the inner surface temperature of the thick aluminium vacuum vessel will be less than 1200C which is required to reduce the overaging effect of the aluminium alloy. (orig.)

  3. Feet sunk in molten aluminium: The burn and its prevention.

    Science.gov (United States)

    Alonso-Peña, David; Arnáiz-García, María Elena; Valero-Gasalla, Javier Luis; Arnáiz-García, Ana María; Campillo-Campaña, Ramón; Alonso-Peña, Javier; González-Santos, Jose María; Fernández-Díaz, Alaska Leonor; Arnáiz, Javier

    2015-08-01

    Nowadays, despite improvements in safety rules and inspections in the metal industry, foundry workers are not free from burn accidents. Injuries caused by molten metals include burns secondary to molten iron, aluminium, zinc, copper, brass, bronze, manganese, lead and steel. Molten aluminium is one of the most common causative agents of burns (60%); however, only a few publications exist concerning injuries from molten aluminium. The main mechanisms of lesion from molten aluminium include direct contact of the molten metal with the skin or through safety apparel, or when the metal splash burns through the pants and rolls downward along the leg. Herein, we report three cases of deep dermal burns after 'soaking' the foot in liquid aluminium and its evolutive features. This paper aims to show our experience in the management of burns due to molten aluminium. We describe the current management principles and the key features of injury prevention. PMID:25687835

  4. Toxicity of dissolved and precipitated aluminium to marine diatoms.

    Science.gov (United States)

    Gillmore, Megan L; Golding, Lisa A; Angel, Brad M; Adams, Merrin S; Jolley, Dianne F

    2016-05-01

    Localised aluminium contamination can lead to high concentrations in coastal waters, which have the potential for adverse effects on aquatic organisms. This research investigated the toxicity of 72-h exposures of aluminium to three marine diatoms (Ceratoneis closterium (formerly Nitzschia closterium), Minutocellus polymorphus and Phaeodactylum tricornutum) by measuring population growth rate inhibition and cell membrane damage (SYTOX Green) as endpoints. Toxicity was correlated to the time-averaged concentrations of different aluminium size-fractions, operationally defined as permeability were observed for any of the three diatoms suggesting that mechanisms of aluminium toxicity to diatoms do not involve compromising the plasma membrane. These results indicate that marine diatoms have a broad range in sensitivity to aluminium with toxic mechanisms related to both dissolved and precipitated aluminium. PMID:26921729

  5. Synergistic effects of zinc borate and aluminium trihydroxide on flammability behaviour of aerospace epoxy system

    Directory of Open Access Journals (Sweden)

    2009-06-01

    Full Text Available The flame retardancy of mono-component epoxy resin (RTM6, widely used for aerospace composites, treated with zinc borate (ZB, aluminium trihydroxide (ATH and their mixtures at different concentrations have been investigated by morphological and thermal characterization. Cone calorimeter data reveal that combustion behaviour, heat release rate peak (PHRR and heat release rate average (HRR Average of RTM6 resin decrease substantially when synergistic effects of zinc borate and aluminium trihydroxide intervene. Thermogravimetric (TGA results and analysis of the residue show that addition higher than 20% w/w of ZB, ATH, and their mixture greatly promotes RTM6 char formation acting as a barrier layer for the fire development. Depending upon the different used flame additives, SEM micrographs indicate that the morphology of residual char could vary from a compact amalgam-like structure, for the RTM6+ZB system, to a granular structure, characterized by very small particles of degraded resin and additive for the ATH.

  6. Aluminium matrix composites fabricated by infiltration method

    Directory of Open Access Journals (Sweden)

    L.A. Dobrzański

    2009-03-01

    Full Text Available Purpose: The aim of this work is to examine the structure and properties of metal matrix composites obtained by infiltration method of porous ceramic preforms by liquid aluminium alloy.Design/methodology/approach: Ceramic preforms were manufactured by the sintering method of ceramic powder. The preform material consists of powder Condea Al2O3 CL 2500, however, as the pore forming the carbon fibers Sigrafil C10 M250 UNS were used. Then ceramic preforms were infiltrated with liquid eutectic EN AC – AlSi12 aluminum alloy. Stereological and structure investigations of obtained composite materials were made on light microscope. The mechanical properties of obtained composite material were investigated in tensile strength test and hardness test.Findings: It was proved that developed technology of manufacturing of composite materials based on the porous ceramic Al2O3 preforms infiltrated by liquid aluminium alloy ensures expected structure and strength Hardness increased about twice compared to the matrix and this process can be used in practice.Practical implications: The presented metal matrix composites fabrication technology allows to obtain locally reinforced elements and near net shape products.Originality/value: Results show the possibility of obtaining the new aluminium matrix composite materials being the cheaper alternative for other materials based on the ceramic fibers.

  7. Plasmonic enhancement of photoluminescence from aluminium nitride

    Science.gov (United States)

    Flynn, Chris; Stewart, Matthew

    2016-03-01

    Aluminium nitride (AlN) films were grown on c-plane sapphire wafers by molecular beam epitaxy (MBE) under aluminium-rich conditions. The excess aluminium (Al) accumulated on the surface of the films as micro-scale droplets 1-10 μm in size, and as Al nanoparticles with diameters in the range 10-110 nm. Photoluminescence (PL) measurements were performed on the AlN samples using a 193 nm Excimer laser as the excitation source. Prior to PL measurements the wafers were cleaved in half. One half of each wafer was submitted to a 10 min treatment in H3PO4 heated to 70 °C to remove the excess Al from the film surface. The remaining half was left in the as-deposited condition. The mean intensities of the near-band-edge PL peaks of the as-deposited samples were 2.0-3.4 times higher compared to the samples subjected to the H3PO4 Al-removal treatment. This observation motivated calculations to determine the optimal Al surface nanosphere size for plasmonic enhancement of PL from AlN. The PL enhancement was found to peak for an Al nanosphere radius of 15 nm, which is within the range of the experimentally-observed Al nanoparticle sizes.

  8. Behaviour and design of aluminium alloy structural elements

    OpenAIRE

    Su, Meini; 蘇玫妮

    2014-01-01

    Aluminium alloys are nonlinear metallic materials with continuous stress-strain curves that are not well represented by the simplified elastic, perfectly plastic material model used in most existing design specifications. The aims of this study are to develop a more efficient design method for aluminium alloy structures by rationally exploiting strain hardening. The key components of this study include laboratory testing, numerical modelling and development of design guidance for aluminium al...

  9. Friction factor of CP aluminium and aluminium–zinc alloys

    Indian Academy of Sciences (India)

    N Vidhya Sagar; K S Anand; A C Mithun; K Srinivasan

    2006-12-01

    Friction factor has been determined for CP aluminium and aluminium–zinc alloys using ring compression test at different temperatures from 303 K to 773 K. It is found that CP aluminium exhibits sticking whereas Al–Zn alloys do not exhibit sticking at elevated temperatures. Hot working of Al–Zn alloy is easier than that of CP aluminium at 773 K. As zinc content increases up to 10 wt% the friction factor decreases up to 0.02.

  10. Softening Behaviour of Selected Commercially Pure Aluminium Model Alloys

    OpenAIRE

    Sande, Gunnar

    2012-01-01

    A characterization of the softening behaviour of four different commercially pure aluminium alloys has been carried out. The work is related to the MOREAL project (Modelling towards value-added recycling friendly aluminium alloys), where the main goal is to quantify the effect of the elements in recyclable aluminium alloys on microstructure and mechanical properties during thermo-mechanical processing. Typical elements are iron (Fe), silicon (Si) and manganese (Mn), and the alloys studied in ...

  11. Aluminium supplier selection for the automotive parts manufacturer

    OpenAIRE

    M. Cieśla

    2016-01-01

    This paper presents a methodology for selection of the optimal sources of supply, which is also known as the problem of supplier selection. Theoretical considerations are expanded with research related to aluminium supplier selection for a hypothetical manufacturer of aluminium parts for transportation equipment located in Poland. Evaluation of five suppliers of aluminium from Poland, Germany and Slovenia has been conducted using a weighted scoring method, a strengths and weaknesses method an...

  12. Tribological characteristics of coatings on aluminium and its alloys

    OpenAIRE

    Abdul-Mahdi, Fadhil S

    1987-01-01

    This thesis was submitted for the degree of Doctor of Philosophy and awarded by Brunel University. Hard anodising on aluminium and its alloys has been widely practised for many years in order to improve the resistance of the otherwise poor wear characteristics of aluminium. In recent years there has been an increasing interest in other treatments and coatings, on both aluminium and other base metals. The aim of this investigation is to explain the tribological performance and wear mechanis...

  13. Wearing tests on aluminium coated with diamond by triboadhesion

    Institute of Scientific and Technical Information of China (English)

    J.M.RodríguezLelis; B.D.Angulo; J.O.Colín; J.PorcayoCalderón

    2001-01-01

    In this work the results obtained from subjecting aluminium coated with diamond by tri-boadhesion to a wearing process with a plane rider. Here it is shown the ratio of the normal toshearing forces, called friction factor, as an indication of the resistance of the surface. It was foundthat the film of the aluminium coated with diamond resisted three times compared with the oxida-tion film of commercial aluminium, which for the purpose of this work was considered withoutcoating.

  14. Un-optimistic Prospects for the Westward Movement of Aluminium

    Institute of Scientific and Technical Information of China (English)

    2014-01-01

    <正>The westward movement of aluminium is essential for the industrial development.Up till now,the northwestern area has planned to construct more than 40 aluminium projects with a total production capacity of over 20 million tons.The future rate of progress of newly constructed projects are directly related to the supplies of the aluminium market,having critical guiding meaning for the trends of

  15. Corrosion of Metal-Matrix Composites with Aluminium Alloy Substrate

    Directory of Open Access Journals (Sweden)

    B. Bobic

    2010-03-01

    Full Text Available The corrosion behaviour of MMCs with aluminium alloy matrix was presented. The corrosion characteristics of boron-, graphite-, silicon carbide-, alumina- and mica- reinforced aluminium MMCs were reviewed. The reinforcing phase influence on MMCs corrosion rate as well as on various corrosion forms (galvanic, pitting, stress corrosion cracking, corrosion fatique, tribocorrosion was discussed. Some corrosion protection methods of aluminium based MMCs were described

  16. Thermal formation of corundum from aluminium hydroxides prepared from various aluminium salts

    Indian Academy of Sciences (India)

    J Temuujin; Ts JADAMBAA; K J D Mackenzie; P Angerer; F Porte; F Riley

    2000-08-01

    Aluminium hydroxides have been precipitated from various aluminium salts and the differences in their thermal behaviour have been investigated. Pseudoboehmite derived from the nitrate, sulfate and chloride all form -Al2O3 at ∼ 400°C but the formation of -Al2O3 at 1200°C occurs more readily in the material derived from the sulfate. This contains a higher concentration of anionic impurities related to differences in the solubility of the original aluminium salts. The sulfate is retained in the gel to higher temperatures at which its eventual decomposition may lead to the formation of a reactive pore structure which facilitates the nucleation of -Al2O3.

  17. 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.

  18. Cold-impregnated aluminium. A new source of nickel exposure.

    Science.gov (United States)

    Lidén, C

    1994-07-01

    A new technique for finishing anodized aluminium was introduced during the 1980s--cold impregnation with nickel. Nickel is available on the surface of cold-impregnated aluminium, as shown by the dimethylglyoxime test. Chemical analysis with EDXA showed that nickel was in the form of NiSO4. A case of work-related allergic contact dermatitis in an engraver with nickel allergy is reported. It transpired that the patient was exposed to nickel in connection with aluminium. It is concluded that cold-impregnated aluminium is a new source of nickel exposure, probably previously unknown to dermatologists. PMID:7924288

  19. Effects of aluminium surface morphology and chemical modification on wettability

    Science.gov (United States)

    Rahimi, M.; Fojan, P.; Gurevich, L.; Afshari, A.

    2014-03-01

    Aluminium alloys are some of the predominant metals in industrial applications such as production of heat exchangers, heat pumps. They have high heat conductivity coupled with a low specific weight. In cold working conditions, there is a risk of frost formation on the surface of aluminium in the presence of water vapour, which can lead to the deterioration of equipment performance. This work addresses the methods of surface modification of aluminium and their effect of the underlying surface morphology and wettability, which are the important parameters for frost formation. Three groups of real-life aluminium surfaces of different morphology: unpolished aluminium, polished aluminium, and aluminium foil, were subjected to surface modification procedures which involved the formation of a layer of hydrophilic hyperbranched polyethyleneglycol via in situ polymerization, molecular vapour deposition of a monolayer of fluorinated silane, and a combination of those. The effect of these surface modification techniques on roughness and wettability of the aluminium surfaces was elucidated by ellipsometry, contact angle measurements and atomic force microscopy. We demonstrated that by employing different types of surface modifications the contact angle of water droplets on aluminium samples can be varied from 12° to more than 120°. A crossover from Cassie-Baxter to Wenzel regime upon changing the surface roughness was also observed.

  20. Friction stir welding (FSW of aluminium foam sandwich panels

    Directory of Open Access Journals (Sweden)

    M. Bušić

    2016-07-01

    Full Text Available The article focuses on the influence of welding speed and tool tilt angle upon the mechanical properties at the friction stir welding of aluminium foam sandwich panels. Double side welding was used for producing butt welds of aluminium sandwich panels applying insertion of extruded aluminium profile. Such insertion provided lower pressure of the tool upon the aluminium panels, providing also sufficient volume of the material required for the weldment formation. Ultimate tensile strength and flexural strength for three-point bending test have been determined for samples taken from the welded joints. Results have confirmed anticipated effects of independent variables.

  1. A Reaction Coating on Aluminium Alloys by Laser Processing

    OpenAIRE

    Zhou, X.B.; De Hosson, J. Th. M.

    1993-01-01

    An aluminium oxide layer of 100 µm in thickness has been successfully coated on aluminium alloy 6061 and pure aluminium using a powder mixture of silicon oxide and aluminium by laser processing. A strong Al/Al2O3 interface was formed. The exothermic chemical reaction between SiO2 and Al may promote the metal/oxide wetting and the formation of Al2O3 layer. This new approach of ceramic coating on metals using a chemical reaction of other ceramics with metals may be applied to other systems.

  2. Synthesis and characterization of Aluminium and Lanthanum hydro-complexes by multinuclear NMR; Sintese e caracterizacao de hidroxocomplexos de AI e La por RMN multinuclear

    Energy Technology Data Exchange (ETDEWEB)

    Leite, Sidnei Quezada M.; Dieguez, Lidia C. [Universidade Federal, Rio de Janeiro, RJ (Brazil). Coordenacao dos Programas de Pos-graduacao de Engenharia; San Gil, Rosane A.S. [Universidade Federal, Rio de Janeiro, RJ (Brazil). Inst. de Quimica

    1997-12-31

    Evidence suggest that the presence of Lanthanum ions in aluminium chloride solutions during base addition cause the formation of complexes which can promote the formation of an unknown macro-cation. These compounds when mixed to smectites are supposed to yield materials of high thermal stability. In order to contribute to the study of this phenomenon, aqueous solutions of aluminium and lanthanum were analysed by nuclear magnetic resonance. The methodology is presented. Results are presented 5 refs., 2 figs., 2 tabs.

  3. Comparative studies of thin film growth on aluminium by AFM, TEM and GDOES characterization

    Science.gov (United States)

    Qi, Jiantao; Thompson, George E.

    2016-07-01

    In this present study, comparative studies of trivalent chromium conversion coating formation, associated with aluminium dissolution process, have been investigated using atomic force microscopy (AFM), transmission electron microscopy (TEM) and glow-discharge optical emission spectroscopy (GDOES). High-resolution electron micrographs revealed the evident and uniform coating initiation on the whole surface after conversion treatment for only 30 s, although a network of metal ridges was created by HF etching pre-treatment. In terms of conversion treatment process on electropolished aluminium, constant kinetics of coating growth, ∼0.30 ± 0.2 nm/s, were found after the prolonged conversion treatment for 600 s. The availability of electrolyte anions for coating deposition determined the growth process. Simultaneously, a proceeding process of aluminium dissolution during conversion treatment, of ∼0.11 ± 0.02 nm/s, was found for the first time, indicating constant kinetics of anodic reactions. The distinct process of aluminium consumption was assigned with loss of corrosion protection of the deposited coating material as evidenced in the electrochemical impedance spectroscopy. Based on the present data, a new mechanism of coating growth on aluminium was proposed, and it consisted of an activation period (0-30 s), a linear growth period (0.30 nm/s, up for 600 s) and limited growth period (0.17 nm/s, 600-1200 s). In addition, the air-drying post-treatment and a high-vacuum environment in the microscope revealed a coating shrinkage, especially in the coatings after conversion treatments for longer time.

  4. Early age corrosion of aluminium in calcium sulfo-aluminate cement based composites

    International Nuclear Information System (INIS)

    At present, encapsulation of low level and intermediate level nuclear wastes using Portland Cement (PC) based matrices is a preferred approach. However, it is now widely accepted that the high pH of the pore solution of these PC-based matrices (usually above pH 12.5) can cause concerns over the stability of certain wastes containing reactive metals, such as aluminium and uranium. One potential low pH system for reducing the corrosion of aluminium is calcium sulfo-aluminate cement (CSA). However, significant heat could be generated from the hydration of CSA, causing another concern to the nuclear industry. In the current study, various additives, namely pulverized fuel ash (PFA), ground granulated blast furnace slag (GGBS) and limestone powder (LSP) were used to replace part of the CSA in order to reduce the heat output. The results indicated that the replacement of CSA with GGBS, PFA and LSP can reduce the heat output of 100% CSA, although it is still higher than the control GGBS/PC 9:1 system. The corrosion rate of aluminium in each of the CSA composites was slightly higher than 100% CSA, however, all the CSA systems had corrosion rates lower than GGBS/PC 9:1 after 15 hours. Therefore, the composite CSA systems investigated in this study provide a good compromise between the heat output and the resistance to the corrosion of aluminium. Hence, offers a good potential for dealing with some historical nuclear wastes where the corrosion of aluminium is a concern. (authors)

  5. Experimental weathering rates of aluminium silicates

    International Nuclear Information System (INIS)

    release rates estimated from the sum of the volume fraction normalized dissolution rates of plagioclase, pyroxene, and olivine are within one order of magnitude of those measured in this study. In addition, these experimental results show that during injection of CO2-charged waters with pH close to 3.6, crystalline basalt preferentially releases Mg and Fe relative to Ca to the fluid phase. The injection of acidic CO2-charged fluids into crystalline basaltic rocks may therefore favour the formation of Mg and Fe carbonates rather than calcite at acidic to neutral conditions. Plagioclase is the most abundant phase in crystalline basalts and thus influences strongly its reactivity. Plagioclase dissolution rates based on Si release show a common U-shaped behaviour as a function of pH where rates decrease with increasing pH at acid condition but increase with increasing pH at alkaline conditions. Constant pH plagioclase dissolution rates increase with increasing anorthite content at acid conditions, in agreement with literature findings. Interpretation and data fitting suggests that plagioclase dissolution rates are consistent with their control by the detachment of Si-rich activated complexes formed by the removal of Al from the mineral framework. Most notably, compared with previous assumptions, plagioclase dissolution rates are independent of plagioclase composition at alkaline conditions, e.g. anorthite-rich plagioclase dissolution rates increase with increasing pH at alkaline conditions. At such conditions rapid plagioclase dissolution rates likely dominate divalent metal release from crystalline basalts to the fluids phase due to its high Ca content. Gibbsite is commonly the first mineral formed during low temperature dissolution of plagioclase. Gibbsite is an aluminium-hydroxide that is found in various soils as well as the dominant phase in many bauxite ores. Gibbsite precipitation rates were measured in closed system reactors at alkaline condition, both at 25 C and 80

  6. A study on the recycling of aluminium alloy 7075 scrap

    Energy Technology Data Exchange (ETDEWEB)

    Oezer, Goekhan [Yildiz Technical Univ., Yildiz (TR). Balkan Centre of Advanced Casting Technologies (BACAT); Marsoglu, Muezeyyen [Yildiz Technical Univ., Yildiz (Turkey). Dept. for Metal and Materials Science Engineering; Burgucu, Sarp

    2012-07-01

    Aluminium and its alloys have recently become an important metal whose area and amount of usage increase more and more, due to their mechanical properties, recycling ability, and penetrability. If it is considered that the bauxite, which is the raw material of aluminium is rare on earth, and also the area and amount of aluminium usage increases over time, the importance of aluminium recycling goes up. aluminium recycling has become crucial by means of both, the potential of the scrap's dependant increase on usage and the primary aluminium production, as it is providing energy and cost savings. 7xxx grades of scrap are collected with other scrap of aluminium alloys in one turn and recycled all together. As the regain of these alloys is not done by isolation of the various grades, the finally recycled ingots result in lower grades. High value aluminium scrap is regrettably not recovered, as it was anticipated. This study is dealing with 7075 aluminium alloys originated from discharged blow molding tools and the rest piece cuttings of blocks and plates. The material has been subjected to an induction furnace, and has been remelted into small ingots and hardened according to 7075 aluminium alloy parameters (hardening aluminium tooling). [German] Aluminium und seine Legierungen sind in den letzten Jahren aufgrund ihrer mechanischen Eigenschaften, ihrer Recyclingfaehigkeit und ihrer Durchlaessigkeit immer bedeutendere metallische Werkstoffe geworden. Unter Beruecksichtigung, dass Bauxit als Rohmaterial selten auf der Erde vorkommt und der Verbrauch mit der Zeit steigt, waechst die Bedeutung des Recyclings von Aluminium. Aluminiumrecycling, zumal es Energieund Kosteneinsparungen ermoeglicht, ist sowohl fuer die schrottabhaengigen Verwendungspotentiale und die PrimaerAluminiumproduktion gleichermassen bedeutend geworden. Die 7xxxx Schrottlegierungen werden in einem Arbeitsgang mit dem Schrott aus anderen Aluminiumlegierungen gesammelt und recycled. Da die

  7. There is (still too much aluminium in infant formulas

    Directory of Open Access Journals (Sweden)

    Burrell Shelle-Ann M

    2010-08-01

    Full Text Available Abstract Background Infant formulas are sophisticated milk-based feeds for infants which are used as a substitute for breast milk. Historically they are known to be contaminated by aluminium and in the past this has raised health concerns for exposed infants. We have measured the aluminium content of a number of widely used infant formulas to determine if their contamination by aluminium and consequent issues of child health persists. Methods Samples of ready-made milks and powders used to make milks were prepared by microwave digestion of acid/peroxide mixtures and their aluminium content determined by THGA. Results The concentration of aluminium in ready-made milks varied from ca 176 to 700 μg/L. The latter concentration was for a milk for preterm infants. The aluminium content of powders used to make milks varied from ca 2.4 to 4.3 μg/g. The latter content was for a soya-based formula and equated to a ready-to-drink milk concentration of 629 μg/L. Using the manufacturer's own guidelines of formula consumption the average daily ingestion of aluminium from infant formulas for a child of 6 months varied from ca 200 to 600 μg of aluminium. Generally ingestion was higher from powdered as compared to ready-made formulas. Conclusions The aluminium content of a range of well known brands of infant formulas remains high and particularly so for a product designed for preterm infants and a soya-based product designed for infants with cow's milk intolerances and allergies. Recent research demonstrating the vulnerability of infants to early exposure to aluminium serves to highlight an urgent need to reduce the aluminium content of infant formulas to as low a level as is practically possible.

  8. Effects of aluminium surface morphology and chemical modification on wettability

    Energy Technology Data Exchange (ETDEWEB)

    Rahimi, M., E-mail: mar@sbi.aau.dk [Department of Energy and Environment, Danish Building Research Institute, Aalborg University, A.C. Meyers Vænge 15, 2450 København SV (Denmark); Fojan, P.; Gurevich, L. [Department of Physics and Nanotechnology, Aalborg University, Skjernvej 4, DK-9220 Aalborg East (Denmark); Afshari, A. [Department of Energy and Environment, Danish Building Research Institute, Aalborg University, A.C. Meyers Vænge 15, 2450 København SV (Denmark)

    2014-03-01

    Highlights: • Successful surface modification procedures on aluminium samples were performed involving formation of the layer of hydrophilic hyperbranched polyethyleneglycol (PEG) via in situ polymerization, molecular vapour deposition of a monolayer of fluorinated silane, and a combination of those. • The groups of surfaces with hydrophobic behavior were found to follow the Wenzel model. • A transition from Cassie–Baxter's to Wenzel's regime was observed due to changing of the surface roughness upon mechanical polishing in aluminium samples. - Abstract: Aluminium alloys are some of the predominant metals in industrial applications such as production of heat exchangers, heat pumps. They have high heat conductivity coupled with a low specific weight. In cold working conditions, there is a risk of frost formation on the surface of aluminium in the presence of water vapour, which can lead to the deterioration of equipment performance. This work addresses the methods of surface modification of aluminium and their effect of the underlying surface morphology and wettability, which are the important parameters for frost formation. Three groups of real-life aluminium surfaces of different morphology: unpolished aluminium, polished aluminium, and aluminium foil, were subjected to surface modification procedures which involved the formation of a layer of hydrophilic hyperbranched polyethyleneglycol via in situ polymerization, molecular vapour deposition of a monolayer of fluorinated silane, and a combination of those. The effect of these surface modification techniques on roughness and wettability of the aluminium surfaces was elucidated by ellipsometry, contact angle measurements and atomic force microscopy. We demonstrated that by employing different types of surface modifications the contact angle of water droplets on aluminium samples can be varied from 12° to more than 120°. A crossover from Cassie–Baxter to Wenzel regime upon changing the surface

  9. Influence of Sulphur Impurities on the Interfacial Tension between Aluminium and Cryolite Alumina Melts

    Science.gov (United States)

    Korenko, Michal

    2007-06-01

    The interfacial tension (IFT) between aluminium and cryolite melts containing different salt additions (AlF3, NaF,Na2SO4) has been measured during electrolysis by the capillary depression method. The technique is based on the measurement of the capillary depression occurring when a capillary, which is moved vertically down through the molten salt layer, passes through the metal/salt interface. The depression is measured by simultaneous video recording of the immersion height of the alumina capillary. The interfacial tension is strongly dependent on the n(NaF)/n(AlF3) ratio. The addition of Na2SO4 decreases the IFT of the aluminium/electrolyte interface. We also found the different influence of the conditions of electrolysis on the IFT in systems with and without Na2SO4. In systems without Na2SO4 the IFT decreases with increasing current density, and in systems with Na2SO4 it increases.

  10. The influence of alloying elements in aluminium on the grain refinement with ALTI5B1

    Directory of Open Access Journals (Sweden)

    Naglič I.

    2009-07-01

    Full Text Available This work deals with the influence of alloying elements in aluminium on the grain refinement with various additions of AlTi5B1. Grain-refinement tests were made at a cooling rate of 15 °C/s. The results revealed that in both aluminium and an Al-Fe alloy the grain size decreases with increasing additions of the AlTi5B1 grain refiner. We found that for the same boron content the grain size was smaller in the case of the Al-Fe alloy. The difference in the grain sizes for the same content of boron was approximately 15 μm; this is considerably smaller than the difference between the grain sizes in samples with the same difference of growth-restricting factor made at slower cooling rates.

  11. Gas heat treatment plants for the aluminium industry; Gasbeheizte Waermebehandlungsanlagen fuer die Aluminium-Industrie

    Energy Technology Data Exchange (ETDEWEB)

    Olberts, P.; Hanus, A. [LOI Thermprocess GmbH, Essen (Germany)

    2004-09-01

    LOI Thermoprocess has developed new, flexible, innovative furnace designs for heat treatment of aluminium in general (car industry) and particularly for cylinder heads, engine units, chassis components, textured components, wheels, rolled sheet and extrusions. The furnaces are heated by means of radiant tubes (recuperators) and by the more usual open gas heating system (flue gas recirculation). (orig.)

  12. The aluminium body has been promoted in Canada; La carrosserie aluminium promue au Canada

    Energy Technology Data Exchange (ETDEWEB)

    Anon.

    2004-02-01

    The aluminium vehicles technology is a technology which allows, with an equivalent structure, to decrease the weight of a car of 40%. Presented by the Alcan firm, this technology is one of the technologies of the year 2003. The Alcan firm has, besides, received the 2003 technology price awarded by the magazine Industry Week. (O.M.)

  13. An Experimental and Numerical Study of Heat Transfer in Aluminium Melting and Remelting Furnaces

    OpenAIRE

    Furu, Jørgen

    2013-01-01

    This work has been a combined experimental and numerical modeling effort aimed to help in the understanding of heat transfer processes when melting aluminium. In addition a newly developed type of oxy-fuel burner was investigated. Objectives set for this project include improving energy efficiency in a typical industry furnace used today and looking at possible new technology to realize higher efficiencies than normally obtained. As a starting point a literature review was done to get an over...

  14. Nickel-aluminium complex: a simple and effective precursor for nickel aluminate (NiAl2O4 spinel

    Directory of Open Access Journals (Sweden)

    Apirat Laobuthee

    2008-01-01

    Full Text Available A reaction of aluminium hydroxide, nickel nitrate and triethanolamine in ethylene glycol provided, in one step, a simple and effective nickel-aluminium complex precursor for NiAl2O4 spinel. On the basis of 1H-, 13C-NMR spectroscopy, and mass spectrometry, the possible structure of the complex was proposed as a trimetallic double alkoxide consisting of two four-coordinate TEA-Al (alumatrane moieties linked via a bridging TEA group enfolding the Ni2+ cation. Transformation of the nickel-aluminium complex to pure spinel occurred when the complex precursor was pyrolysed at 1000C for 5 h. The BET surface area of the pyrolysed product was found to be 31 m2/g. In addition, the morphology of the powder product was examined by SEM.

  15. Enhanced corrosion protection by microstructural control of aluminium brazing sheet

    NARCIS (Netherlands)

    Norouzi Afshar, F.

    2013-01-01

    Aluminium brazing sheet is a sandwich material made out of two aluminium alloys (AA4xxx/AA3xxx) and is widely used in automotive heat exchangers. One of the main performance criteria for heat exchanger units is the lifetime of the product. The lifetime of the heat exchanger units is determined by th

  16. Thermoelectric power of multilayer compositions of aluminium and carbon nanotubes

    International Nuclear Information System (INIS)

    Changing the thermoelectric power monolayer and multilayer aluminium foil and multilayer foils compositions of aluminium and carbon nanotubes is the deformation ε < 60% due to the scattering of conduction electrons at dislocations and ε=(70 ...96)% - due to their scattering on the boundaries between the layers (thermoelectric size effect)

  17. Phase analysis of nickel surface layer implanted by aluminium

    International Nuclear Information System (INIS)

    The experimental result of study of microstructure and phase composition in the surface zone of nickel target under intensive implantation of aluminium ions on a vacuum-arc and plasma flow source Raduga-5 are presented. It was established that the fine dispersed intermetallic precipitates Ni3Al and NiAl and the variable composition solid solution of aluminium in nickel are formed

  18. CAD implementation of design rules for aluminium extrusion dies

    NARCIS (Netherlands)

    Ouwerkerk, van Gijs

    2009-01-01

    Aluminium extrusion is an industrial forming process that is used to produce long profiles of a constant cross-section. This cross-section is shaped by the opening in a steel tool known as the die. The understanding of the mechanics of the aluminium extrusion process is still limited. The flow of al

  19. Spark counting technique with an aluminium oxide film

    International Nuclear Information System (INIS)

    Automatic spark counting of etch-pits on a polycarbonate film produced by nuclear fission fragments is now used for neutron monitoring in several countries. A method was developed using an aluminium oxide film instead of a polycarbonate as the neutron detector. Aluminium oxide films were prepared as follows: A cleaned aluminium plate as an anode and a nickel plate as a cathode were immersed in dilute sulfuric acid solution and electric current flowed between the electrodes at 12degC for 10-30 minutes. Electric current density was about 10 mA/cm2. The aluminium plate was then kept in boiling water for 10-30 minutes for sealing. The thickness of the aluminium oxide layer formed was about 1μm. The aluminium plate attached to a plate of suitable fissionable material, such as uranium or thorium, was irradiated with neutrons and set in a usual spark counter for fission track counting. One electrode was the aluminium plate and the other was an aluminized polyester sheet. Sparked pulses were counted with a usual scaler. The advantage of using spark counting with an aluminium oxide film for neutron monitoring is rapid measurement of neutron exposure, since chemical etching which is indispensable for spark counting with a polycarbonate detector film, is not needed. (H.K.)

  20. The peculiarities of scandium and yttrium dissolution in aluminium melt

    International Nuclear Information System (INIS)

    The investigation results of dissolution of scandium and yttrium in liquid aluminium at 973-1173 K are presented in this work. It was shown that coefficient value of yttrium diffusion in aluminium melt equals to 3,566-17,9070 m2/sec, and scandium 9,692-4,072 m2/sec.

  1. Haemodialysis related osteomalacia: a staining method to demonstrate aluminium

    OpenAIRE

    Buchanan, Malcolm RC; Ihle, Benno U; Dunn, Cheryl M

    1981-01-01

    A slight modification in tissue processing and staining technique enables a previously described method for staining aluminium to be used to demonstrate aluminium in osteomalacia associated with haemodialysis. The stain appears to be accurate in diagnosing this condition and may assist in establishing the diagnosis before severe osteomalacia develops.

  2. Aluminium Alloy Cast Shell Development for Torpedoes

    Directory of Open Access Journals (Sweden)

    Vijaya Singh

    2005-01-01

    Full Text Available The sand-cast aluminium alloy cylindrical shells were developed for the advanced experimental torpedo applications. The components had intricate geometry, thin-walled sections, and stringent property requirements. The casting defects, such as shrinkage, porosity, incomplete filling of thin sections, cold shuts, inclusions and dimensional eccentricity, etc were found inthe initial castings trials. improvements in casting quality were achieved through modified methodology, selective chilling, risering, and by introducing ceramic-foam filters in the gatingsystem. The heat-treated and machined components met radiographic class I grade C/E standards, mechanical properties to BS1490 specifications, and leakage and hydraulic pressure testrequirements relevant for such applications.

  3. Dissolved aluminium in the Southern Ocean

    OpenAIRE

    Middag, R.; Slooten van, C.; Baar, H.J.W. de; Laan, P.

    2011-01-01

    Dissolved aluminium (Al) occurs in a wide range of concentrations in the world oceans. The concentrations of Al in the Southern Ocean are among the lowest ever observed. An all-titanium CTD sampling system makes it possible to study complete deep ocean sections of Al and other trace elements with the same high vertical resolution of 24 depths as normal for traditional CTD/Rosette sampling. Overall, 470 new data points of Al are reported for 22 full depth stations and 24 surface sampling posit...

  4. Roll casting of 5182 aluminium alloy

    OpenAIRE

    Haga, T; M. Mtsuo; D. Kunigo; Hatanaka, Y; R. Nakamuta; H. Watari; S. Kumai

    2009-01-01

    Purpose: of this paper is investigation of the ability of the high speed roll casting of 5182 aluminium alloy. Appropriate twin roll caster to cast the 5182 strip was researched.Design/methodology/approach: Method used in the present study was an unequal diameter twin roll caster and a vertical type high speed twin roll caster equipped with mild steel rolls without parting material.Findings: are that the vertical type high speed twin roll caster was effective to cast 5182 strip at high speed....

  5. On the Crystallization of Terbium Aluminium Garnet

    OpenAIRE

    Ganschow, S.; Klimm, D.; Reiche, P.; Uecker, R.

    2008-01-01

    Attempts to grow terbium aluminium garnet (Tb3Al5O12, TAG) by the Czochralski method lead to crystals of millimeter scale. Larger crystals could not be obtained. DTA measurements within the binary system showed that TAG melts incongruently at 1840 deg. C. The perovskite (TbAlO3, TAP) with a congruent melting point of 1930 deg. C is the most stable phase in this system. The region for primary crystallization of TAP covers the chemical composition of TAG and suppresses the primary crystallizati...

  6. Friction stir welding of single crystal aluminium

    DEFF Research Database (Denmark)

    Fonda, Richard Warren; Wert, John A.; Reynolds, A.P.;

    2007-01-01

    Friction stir welds were prepared in different orientations in an aluminium single crystal. The welds were quenched to preserve the microstructure surrounding the tool and then electron backscattered diffraction was used to reveal the generation of grain boundaries and the evolution of...... crystallographic texture around the tool in each weld. The extent of both dynamic recrystallisation and conventional recrystallisation varied considerably as a function of weld orientation. As the base plate begins to interact with the deformation field surrounding the tool, regions of the single crystal rotate to...

  7. Strain rate sensitivity studies on bulk nanocrystalline aluminium by nanoindentation

    Energy Technology Data Exchange (ETDEWEB)

    Varam, Sreedevi; Rajulapati, Koteswararao V., E-mail: kvrse@uohyd.ernet.in; Bhanu Sankara Rao, K.

    2014-02-05

    Nanocrystalline aluminium powder synthesized using high energy ball milling process was characterized by X-ray Diffraction (XRD) and Transmission Electron Microscopy (TEM). The studies indicated the powder having an average grain size of ∼42 nm. The consolidation of the powder was carried out by high-pressure compaction using a uni-axial press at room temperature by applying a pressure of 1.5 GPa. The cold compacted bulk sample having a density of ∼98% was subjected to nanoindentation which showed an average hardness and elastic modulus values of 1.67 ± 0.09 GPa and 83 ± 8 GPa respectively at a peak force of 8000 μN and a strain rate of 10{sup −2} s{sup −1}. Achieving good strength along with good ductility is challenging in nanocrystalline metals. When enough sample sizes are not available to measure ductility and other mechanical properties as per ASTM standards, as is the case with nanocrystalline materials, nanoindentation is a very promising technique to evaluate strain rate sensitivity. Strain rate sensitivity is a good measure of ductility and in the present work it is measured by performing indentation at various loads with varying loading rates. Strain rate sensitivity values of 0.024–0.054 are obtained for nanocrystalline Al which are high over conventional coarse grained Al. In addition, Scanning Probe Microscopy (SPM) image of the indent shows that there is some plastically flown region around the indent suggesting that this nanocrystalline aluminium is ductile.

  8. Durability of Lacquered Aluminium Profile Considering Tropical Weather Conditions

    Directory of Open Access Journals (Sweden)

    Rigoberto Marrero Águila

    2013-11-01

    Full Text Available Searching for solutions against the degradation of materials by corrosion effect, is a common practice to use alloys such as aluminium instead of steel due to the advantages obtained. The lacquered aluminium profiles can substitute other materials like wood, in the carpentry production, becoming an economic saving. There is an increasingly use of aluminium replacing other traditional materials in the constructions in process, but its quality has been reduced in a considerable amount of installations. In this research, aluminium profiles from five different sources were submitted to a trial in natural exposition conditions at the Tropical weather condition Testing Lab, in order to evaluate their behaviour and establish, for the first time in our country, standing rules for lacquered aluminium profiles to be strictly fulfilled by manufacturers and importers. The results will allow modifying thickness standards of this type of coating, to guaranty its durability and to eliminate the failures provoked by our high severe weather conditions.

  9. Volatilisation and oxidation of aluminium scraps fed into incineration furnaces

    International Nuclear Information System (INIS)

    Highlights: ► Aluminium packaging partitioning in MSW incineration residues is evaluated. ► The amount of aluminium packaging recoverable from the bottom ashes is evaluated. ► Aluminium packaging oxidation rate in the residues of MSW incineration is evaluated. ► 80% of aluminium cans, 51% of trays and 27% of foils can be recovered from bottom ashes. - Abstract: Ferrous and non-ferrous metal scraps are increasingly recovered from municipal solid waste incineration bottom ash and used in the production of secondary steel and aluminium. However, during the incineration process, metal scraps contained in the waste undergo volatilisation and oxidation processes, which determine a loss of their recoverable mass. The present paper evaluates the behaviour of different types of aluminium packaging materials in a full-scale waste to energy plant during standard operation. Their partitioning and oxidation level in the residues of the incineration process are evaluated, together with the amount of potentially recoverable aluminium. About 80% of post-consumer cans, 51% of trays and 27% of foils can be recovered through an advanced treatment of bottom ash combined with a melting process in the saline furnace for the production of secondary aluminium. The residual amount of aluminium concentrates in the fly ash or in the fine fraction of the bottom ash and its recovery is virtually impossible using the current eddy current separation technology. The average oxidation levels of the aluminium in the residues of the incineration process is equal to 9.2% for cans, 17.4% for trays and 58.8% for foils. The differences between the tested packaging materials are related to their thickness, mechanical strength and to the alloy.

  10. New sheet aluminium qualities for low-cost lightweight constructions; Neue Aluminium-Blechqualitaeten fuer den kosteneffizienten Leichtbau

    Energy Technology Data Exchange (ETDEWEB)

    Bloeck, M.; Furrer, P. [Novelis Technology AG, Neuhausen (Switzerland)

    2005-11-01

    Aluminium alloys used for car bodies have a wide range of material characteristics. New developments focus on selective development of material and surface characteristics for obtaining sheet aluminium qualities optimized for specific applications. These and further measures taken by Novelis are to reduce material consumption, simplify process steps in motor car manufacturing and reducing the overall system cost. (orig.)

  11. Design of the lines of aluminium drawing. Part 2; Conception des filieres de filage d'aluminium. Partie 2

    Energy Technology Data Exchange (ETDEWEB)

    Cescutti, J.P.; Ravaille, N. [Pechiney, Div. Filiage, 75 - Paris (France)

    2005-12-15

    This work is the second part of the file 'design of the lines of aluminium drawing'. It gives elements for structuring the analysis of the progress ways in the field of the design of the lines of aluminium extrusion. (O.M.)

  12. Aluminium and its alloys: weldability, welding metallurgy; L'aluminium et ses alliages: soudabilite, metallurgie du soudage

    Energy Technology Data Exchange (ETDEWEB)

    Boucher, Ch.

    2000-07-01

    The aim of this book is to give technological and use elements of the welding processes as well as the knowledge in weldability and metallurgy required for a better control of the welding of aluminium alloys. In the first part are detailed the generalities on aluminium alloys, their properties and uses sectors. The bases of the physical metallurgy of the aluminium alloys are dealt with too. The second part concerns the welding and the related techniques as well as the properties of the assemblies. Several supplements give useful data for the construction with aluminium alloys. This book is particularly devoted to engineers and technicians using or having to use for the first time the welding of aluminium alloys. (O.M.)

  13. Hearing conservation in the primary aluminium industry

    Science.gov (United States)

    Frisch, N.; Dixon-Ernst, C.; Chesson, B. J.; Cullen, M. R.

    2016-01-01

    Background Noise-induced hearing loss has been an intractable problem for heavy industry. Aims To report our experience in reducing the incidence of age-corrected confirmed 10 dB hearing shifts (averaged over 2, 3 and 4kHz) in employees in the primary aluminium industry in Australia over the period 2006–13. Methods We analysed annual audiometric data to determine the number of permanent hearing shifts that occurred in employees in two bauxite mines, three alumina refineries and two aluminium smelters. Annual hearing shift rates were calculated based on the number of employees tested per year. Hearing conservation initiatives undertaken during the study period are described. An assessment of similar exposure group noise exposures was also undertaken to determine the magnitude of noise exposure reduction during the study period. Results Across all operations, hearing shift rates declined from 5.5% per year in 2006 to 1.3% per year in 2013 (P < 0.001). The decline in shift rates was greater in mines and refineries, where baseline shift rates were higher, than in smelter workers. Modest reductions in noise exposure occurred during the study period. Conclusions We observed a substantial decline in hearing shift rates during the study period. We describe the hearing conservation initiatives that were collectively associated with this decline. We suspect these initiatives could be deployed relatively easily and at modest cost in other industries with noise-exposed employees. PMID:26470945

  14. Reactions on carbon anodes in aluminium electrolysis

    Energy Technology Data Exchange (ETDEWEB)

    Eidet, Trygve

    1997-12-31

    The consumption of carbon anodes and energy in aluminium electrolysis is higher than what is required theoretically. This thesis studies the most important of the reactions that consume anode materials. These reactions are the electrochemical anode reaction and the airburn and carboxy reactions. The first part of the thesis deals with the kinetics and mechanism of the electrochemical anode reaction using electrochemical impedance spectroscopy. The second part deals with air and carboxy reactivity of carbon anodes and studies the effects of inorganic impurities on the reactivity of carbon anodes in the aluminium industry. Special attention is given to sulphur since its effect on the carbon gasification is not well understood. Sulphur is always present in anodes, and it is expected that the sulphur content of available anode cokes will increase in the future. It has also been suggested that sulphur poisons catalyzing impurities in the anodes. Other impurities that were investigated are iron, nickel and vanadium, which are common impurities in anodes which have been reported to catalyze carbon gasification. 88 refs., 92 figs., 24 tabs.

  15. Study on aluminium-based single films.

    Science.gov (United States)

    Vinod Kumar, G S; García-Moreno, F; Babcsán, N; Brothers, A H; Murty, B S; Banhart, J

    2007-12-28

    In the present paper the authors studied isolated metallic films made from the same material used for making metallic foams, and then characterised their properties. Metal films were made from a liquid aluminium alloy reinforced with ceramic particles of known concentration. Melts without such particles were also investigated. It is shown that stable films could not be made from Al-Si alloy having no particles, and just extremely thin and fragile films could be made from commercially-pure Al. In contrast, aluminium alloys containing particles such as SiC and TiB(2) allowed pulling thin, stable films, which did not rupture. Significant thinning of films was observed when the particle concentration in the melt decreased. By in situ X-ray monitoring of liquid films during pulling, film thickness and drainage effects within the liquid film could be studied. The morphology and microstructure of films was characterised after solidification. Our work shows that the question of how foams are stabilised can be studied using a simplified system such as a film, instead of having to deal with the multitude of different structural elements present in a foam. PMID:18060172

  16. Aluminium matrix composites: Challenges and opportunities

    Indian Academy of Sciences (India)

    M K Surappa

    2003-02-01

    Aluminium matrix composites (AMCs) refer to the class of light weight high performance aluminium centric material systems. The reinforcement in AMCs could be in the form of continuous/discontinuous fibres, whisker or particulates, in volume fractions ranging from a few percent to 70%. Properties of AMCs can be tailored to the demands of different industrial applications by suitable combinations of matrix, reinforcement and processing route. Presently several grades of AMCs are manufactured by different routes. Three decades of intensive research have provided a wealth of new scientific knowledge on the intrinsic and extrinsic effects of ceramic reinforcement vis-a-vis physical, mechanical, thermo-mechanical and tribological properties of AMCs. In the last few years, AMCs have been utilised in high-tech structural and functional applications including aerospace, defence, automotive, and thermal management areas, as well as in sports and recreation. It is interesting to note that research on particle-reinforced cast AMCs took root in India during the 70’s, attained industrial maturity in the developed world and is currently in the process of joining the mainstream of materials. This paper presents an overview of AMC material systems on aspects relating to processing, microstructure, properties and applications.

  17. Aluminium alloys containing iron and nickel

    International Nuclear Information System (INIS)

    The first part of this report addresses mechanism, kinetics and structure factors of aluminium alloys containing iron and nickel in water and high temperature steam. The studied alloys contain from 0.3 to 0.7 per cent of iron, and 0.2 to 1.0 per cent of nickel. Corrosion resistance and corrosion structure have been studied. The experimental installation, process and samples are presented. Corrosion structures in water at 350 C are identified and discussed (structure of corrosion products, structure of metal-oxide interface), and then in steam at different temperatures (350-395 C). Corrosion kinetics is experimentally studied (weight variation in time) in water at 350 C and in steam at different temperatures. Reactions occurring at over-heated steam (more than 400 C) are studied, and the case of welded alloys is also addressed. The second part addresses the metallurgical mechanism and processes influencing aluminium alloy resistance to corrosion by high temperature water as it appeared that separated phases protect the solid solution through a neighbourhood action. In order to avoid deep local corrosions, it seems necessary to multiply protective phases in an as uniform as possible way. Some processes enabling this result are described. They belong to conventional metallurgy or to powder metallurgy (with sintering and extrusion)

  18. Lattice site occupation of insoluble impurity atoms in aluminium after implantation and irradiation

    International Nuclear Information System (INIS)

    Several elements, whose atoms are oversized and insoluble in aluminium, were implanted in aluminium single crystals at different temperatures. The substitutional fraction and the lattice site location were determined using the ion-channeling technique. The substitutional fractions obtained by in situ analyses are strongly dependent on the implantation temperature. At implantation and analysis temperatures below the temperature of stage III the substitutional fraction is significant larger than at temperatures above. With increasing heat of solution the substitutional fraction decreases for all implantation temperatures. The nonsubstitutional component consists of impurity atom-vacancy complexes. These complexes are formed in the cooling phase of the cascade. At temperatures above the temperature of stage III additional free mobile vacancies were captured by the impurity atoms. The capture radius is correlated with the heat of solution and the size mismatch energy. The results constitute for the first time an experimental confirmation of molecular dynamics calculations of cascade evolution. (orig./BHO)

  19. Reconstruction of 2D Al3Ti on TiB2 in an aluminium melt

    International Nuclear Information System (INIS)

    It has been widely considered that Al3Ti is involved in the aluminium nucleation on TiB2, although the mechanism has not been fully understood. In this paper molecular dynamics has been conducted to investigate this phenomenon at an atomistic scale. It was found that a two-dimensional Al3Ti layer may remain on TiB2 above the aluminium liquidus. In addition, the results showed that this 2D Al3Ti undergoes interface reconstruction by forming a triangular pattern. This triangular pattern consists of different alternative stacking sequences. The transition region between the triangles forms an area of strain concentration. By means of this mechanism, this interfacial Al3Ti layer stabilizes itself by localizing the large misfit strain between TiB2 and Al3Ti This reconstruction is similar to the hdp-fcc interface reconstruction in other systems which has been observed experimentally.

  20. Evaluation of the mechanical properties of microarc oxidation coatings and 2024 aluminium alloy substrate

    CERN Document Server

    Xue Wen Bin; Deng Zhi Wei; Chen Ru Yi; Li Yong Liang; Zhang Ton Ghe

    2002-01-01

    A determination of the phase constituents of ceramic coatings produced on Al-Cu-Mg alloy by microarc discharge in alkaline solution was performed using x-ray diffraction. The profiles of the hardness, H, and elastic modulus, E, across the ceramic coating were determined by means of nanoindentation. In addition, a study of the influence of microarc oxidation coatings on the tensile properties of the aluminium alloy was also carried out. The results show that the H-and E-profiles are similar, and both of them exhibit a maximum value at the same depth of coating. The distribution of the alpha-Al sub 2 O sub 3 phase content determines the H- and E-profiles of the coatings. The tensile properties of 2024 aluminium alloy show less change after the alloy has undergone microarc discharge surface treatment.

  1. Evaluation of the mechanical properties of microarc oxidation coatings and 2024 aluminium alloy substrate

    Energy Technology Data Exchange (ETDEWEB)

    Xue Wenbin [Key Laboratory for Radiation Beam Technology and Materials Modification, Institute of Low Energy Nuclear Physics, Beijing Normal University, Beijing, 100875 (China); Wang Chao [Key Laboratory for Radiation Beam Technology and Materials Modification, Institute of Low Energy Nuclear Physics, Beijing Normal University, Beijing, 100875 (China); Deng Zhiwei [Key Laboratory for Radiation Beam Technology and Materials Modification, Institute of Low Energy Nuclear Physics, Beijing Normal University, Beijing, 100875 (China); Chen Ruyi [Key Laboratory for Radiation Beam Technology and Materials Modification, Institute of Low Energy Nuclear Physics, Beijing Normal University, Beijing, 100875 (China); Li Yongliang [Analytical and Testing Centre, Beijing Normal University, Beijing, 100875 (China); Zhang Tonghe [Key Laboratory for Radiation Beam Technology and Materials Modification, Institute of Low Energy Nuclear Physics, Beijing Normal University, Beijing, 100875 (China)

    2002-11-11

    A determination of the phase constituents of ceramic coatings produced on Al-Cu-Mg alloy by microarc discharge in alkaline solution was performed using x-ray diffraction. The profiles of the hardness, H, and elastic modulus, E, across the ceramic coating were determined by means of nanoindentation. In addition, a study of the influence of microarc oxidation coatings on the tensile properties of the aluminium alloy was also carried out. The results show that the H-and E-profiles are similar, and both of them exhibit a maximum value at the same depth of coating. The distribution of the {alpha}-Al{sub 2}O{sub 3} phase content determines the H- and E-profiles of the coatings. The tensile properties of 2024 aluminium alloy show less change after the alloy has undergone microarc discharge surface treatment.

  2. The Effects of Cocos Nucifera (Coconut Shell on the Mechanical and Tribological Properties of Recycled Waste Aluminium Can Composites

    Directory of Open Access Journals (Sweden)

    J.O. Agunsoye

    2014-06-01

    Full Text Available The dry sliding wear behaviour and mechanical properties of recycled aluminium metal matrix composite reinforced with 5 and 10 % coconut shell particles (CSp has been investigated. The particle size of Cocosnucifera (coconut shell that were used ranges from 50-300µm. The wear behaviors of developed samples were investigated under varied loads and speed using pin on disc equipment. The samples were also subjected to tensile, impact and hardness test. The result shows that the additions of coconut shell particles improved the wear resistance of the recycled aluminium can/CSp composites at low Speed (2.36 m/s. However, with increase in Speed (4.72 m/s, an increase in the specific wear rates were observed. Increasing the coconut shell particles additions to the recycled waste aluminium cans (RWAlC reduced the impact resistance, hence the toughness of the RWAlC/CSp composite samples. However, the impact resistance of the composites increased as the Cocosnucifera particle size increased. The result of the filler size variation shows that decrease in filler particles size improved the tensile strength and yield strength of the developed aluminium metal matrix /CSp composite. The hardness of the composite increased with increased additions of the filler within the matrix.

  3. Inhibitive Behaviour of Corrosion of Aluminium Alloy in NaCl by Mangrove Tannin

    International Nuclear Information System (INIS)

    Anticorrosion potential of mangrove tannins on aluminium alloys AA6061 in NaCl solution has been studied using potentiodynamic polarisation method and scanning electron microscopy (SEM). The study was carried out in different pH of corrosive medium in the absence and presence of various concentrations of tannin. The corrosion inhibition behaviour of the mangrove tannin on AA6061 aluminium alloy corrosion was found to be dependant on the pH of NaCl solution. Our results showed that the inhibition efficiency increased with increasing tannins concentration in chloride solution at pH 6. Treatment of aluminium alloy 6061 with all concentrations of mangrove tannins reduced the current density, thus decreased the corrosion rate. Tannins behaved as mixed inhibitors at pH 6 and reduction in current density predominantly affected in cathodic reaction. Meanwhile, at pH 12, addition of tannins shifted the corrosion potential to more cathodic potentials and a passivating effect was observed in anodic potentials. SEM studies have shown that the addition of tannins in chloride solution at pH 12 reduced the surface degradation and the formation of pits. (author)

  4. Remelting of Aluminium by Continuous Submersion of Rolled Scrap

    Energy Technology Data Exchange (ETDEWEB)

    Farner, Snorre

    2000-12-01

    . More than 200 experiments were performed, and by comparing the penetration depth at different feeding velocities and melt temperatures to model predictions, the two heat-transfer coefficients h{sub l} and h{sub g} could be determined by curve fitting. They agree reasonably well with values found in the literature and calculated from boundary-layer theory. In a few experiments, the plate feeding was recorded on video tape, and the cross section of some plates was studied in a microscope. Feeding of somewhat thicker plates was also tried. This gave valuable background information for comparing the experiments to the model. We believe that snap-off of the plate due to low mechanical strength around the melting temperature may affect the measurement of the penetration depth of the plate. Attempts were also made to measure the temperature in the plate by attaching thermocouples to its surface. The obtained temperature profiles in the plate were compared to the model predictions, but the method needs improvement. A criterion for formation of a shell is formulated and tested against experimental observations. Qualitative agreement is achieved. Even if there is no shell formation, it seems that there will be an air film with thermal resistance 1/h{sub g}. This indicates that the melting rate will be independent of whether a shell is formed or not. Two additional models with only one heat-transfer coefficient are also developed in order to challenge the main model. From this analysis it is found that the use of two heat-transfer coefficients is necessary to describe the system. The model should be of direct interest when feeding rolled scrap into molten aluminium. Improvement of the model can be attained by reconsidering the assumptions made, but then numerical methods must undoubtedly be applied. These new models should include the snap-off mechanism. (author)

  5. Effect of Aluminium Content in Aluminium Pillared Montmorillonite To Its Surface Acidity Properties

    Directory of Open Access Journals (Sweden)

    Is Fatimah

    2011-07-01

    Full Text Available Aluminium pillared montmorillonites from Indonesian natural montmorillonite has been prepared using Al13 Keggin ion pillaring precursor in varied concentrations. Herein we studied their characterization and catalysis application for esterification reaction. X-ray diffraction (XRD, energy dispersive x-ray analysis (EDX, and BET gas sorption analysis were employed to characterize the prepared materials besides the characterization on surface acidity by pyridine and n-butylammine adsorptions and FTIR analysis. The result showed that significant improvement on physicochemical character data was obtained by a pillarization process. Such a process also provided improvements on catalytic activities in esterification reactions. The effect of aluminium content on material characters was discussed in this paper. It was observed from the catalytic activity tests that pillared montmorillonite samples demonstrated higher activity in esterification reaction relative to the raw montmorillonite. It was found that surface profile of materials consist of specific surface area, pore volume and Lewis acidity were significantly affect the catalyst activity.

  6. Preparation of Aluminium Oxynitride by Carbothermal Reduction of Aluminium Oxide in a Flowing N2 Atmosphere

    Institute of Scientific and Technical Information of China (English)

    LIYa-wei; YUANRun-zhang; 等

    1996-01-01

    Carbothermal reduction of alumina into aluminium oxynitride(AlON) spinel in a flowing nitrogen atmosphere was studied.The effects of Al2O3/C ratio temperature,soaking time,heating rate molding pressure of samples,and nitrogen flow rate on reactions were investigated.Then the stability of AlON was elucidated and AlON wa confirmed as an intermediate compound in reduction of alumina.

  7. INTEROGATION OF THE MANUFACTURING ROUTE OF ALUMINIUM AA 1050 USED IN LITHOGRAPHIC APPLICATION

    OpenAIRE

    Witkowska, Malgorzata Danuta

    2013-01-01

    The aluminium AA1050 alloy, known as commercially pure aluminium, contains 99.5% Al, together with Fe and Si as major alloying elements. During fabrication of aluminium substrates for lithographic printing plates in Bridgnorth Aluminium Ltd, the AA 1050 aluminium alloy proceeds through various stages of thermomechanical processing, with the conditions at each processing stage influencing the microstructure of the final coil. Because of its specific gravity, tensile strength, surface performa...

  8. Effect of filtration on reoxidation proceses in aluminium alloys

    Directory of Open Access Journals (Sweden)

    D. Bolibruchova

    2010-01-01

    Full Text Available This article is focused on reoxidation processes during filtration of aluminium alloys. Many of our experimental works pointed out, that using filtration media placed in gating system causes reoxidation of poured aluminium alloy. Main aim of our latest work was to validate our arguments, that filter in gating system can be considered as obstacle for continuous pouring, with help of computer simulations. This article is only a small part of our researches focused on reoxidation processes during filtration of aluminium alloys.

  9. Aluminium: Aluminij: kovina izbire: the metal of choice:

    OpenAIRE

    Gándara, María Josefa Freiría

    2013-01-01

    This article summarizes the importance of aluminium as the metal of choice formany applications. Aluminium is a lightweight, durable metal. It is silvery in appearance when freshly cut, is a good conductor of heat and electricity, and is easily shaped by moulding and extruding. Aluminium has two main advantages when compared with other metals. Firstly, it has a low density, about one-third that of iron and copper. Secondly, although it reacts rapidly with the oxygen in air, it forms a thin, t...

  10. Cold forming of aluminium - State of the art

    DEFF Research Database (Denmark)

    Bay, Niels

    1997-01-01

    The ongoing development of cold forging technology has been manifested lately by the increasing application of components in cold forged aluminium alloys. Applying precipitation hardening alloys components with great strength/weight ratio can be produced with a strength comparable to that of...... unalloyed steel. After description of the different types of alloys and their individual properties and applications, the special requirements for tool design by cold forging in aluminium is discussed. Finally, a large number of industrial examples on cold forged aluminium components are presented. (C) 1997...

  11. Radiation-induced creep of copper, aluminium and their alloys

    International Nuclear Information System (INIS)

    The results of creep studies on copper, aluminium and their alloys with and without neutron irradiation are presented. The experiments are carried out at the WWR-K reactor at the neutron fluence of 1.4.1016 n/m2.s (2.5.1016 n/m2.s, E>0.1 MeV). Polycrystalline copper (99.99 and 99.95%), aluminium (99.99%) and the alloys of copper with 4 at% of titanium, of aluminium with 4.2% of copper are studied within the temperature interval 0.31-0.51 Tm. (orig.)

  12. 59Fe distribution in continuously cast aluminium strip

    International Nuclear Information System (INIS)

    The problems are discussed of the homogeneity of continuously cast aluminium strips by horizontal casting. Theoretically discussed are phenomena present during primary solidification, namely the nonhomogeneous distribution of admixtures and impurities in primary solidified dendritic cells. A survey is given of the distribution of coefficients of basic admixtures and impurities in aluminium. Experimental investigation was carried out within the verification of theoretical research results, of the distribution of iron in continuously cast aluminium strips using radioactive iron 59Fe in form of radioactive foundry alloy containing 1.8% 59Fe. (author). 13 figs., 1 tab

  13. Corrosion issues of powder coated AA6060 aluminium profiles

    DEFF Research Database (Denmark)

    Din, Rameez Ud; Valgarðsson, Smári; Jellesen, Morten Stendahl;

    2015-01-01

    In this study detailed microstructural investigation of the reason for unexpected corrosion of powder coated aluminium alloy AA6060 windows profiles has been performed. The results from this study reveals that the failure of the window profiles was originated from the surface defects present...... on the extruded AA6060 aluminium profile after metallurgical process prior to powder coating. Surface defects are produced due to intermetallic particles in the alloy, which disturb the flow during the extrusion process. The corrosion mechanism leading to the failure of the powder coated AA6060 aluminium profiles...

  14. Study of fatigue behaviour of 7475 aluminium alloy

    Indian Academy of Sciences (India)

    B B Verma; J D Atkinson; M Kumar

    2001-04-01

    Fatigue properties of a thermomechanically treated 7475 aluminium alloy have been studied in the present investigation. The alloy exhibited superior fatigue life compared to conventional structural aluminium alloys and comparable stage II crack growth rate. It was also noticed that the fatigue crack initiated from a surface grain and the crack extension was dominated by ductile striations. Analysis also revealed that this alloy possessed fracture toughness and tensile properties superior to that noticed with other structural aluminium alloys. Therefore the use of this alloy can safely reduce the overall weight of the aircraft.

  15. Mechanical alloying of aluminium-lithium-magnesium alloy powders

    International Nuclear Information System (INIS)

    The production of high-purity aluminium-lithium-magnesium alloy powders, by mechanical alloying through grinding in a vibratory mill under high vacuum at room temperature, is described in details. The source materials for the grinding mixture were: aluminium-lithium alloy powder obtained by thermal vacuum-dehydrogenization of AlLiH4 hydride; magnesium metal powder; and chemically deoxidized aluminium metal powder. The implications which arose from the high reactivity of the component elements are discussed, and the measures taken to overcome them are described. The procedures used for the chemical analysis and powder characterization are given. (orig.)

  16. Orbital friction stir welding of aluminium pipes

    International Nuclear Information System (INIS)

    Friction stir welding (FSW) was originally developed for flat plates. This contribution shows how it can be applied to the welding of aluminium pipes. Pipes made of AlMG 3 (EN5754), AlMg 4.5Mn (EN5083) and AlMgSi 0.5 (EN6106) with dimensions of Da 600 and 520 x 10-8 mm were welded. The FSW orbital system comprises an annular cage with integrated FSW head, a hydraulic system, and a control unit. The welds were tested successfully according to EN 288. The mechanical and technical properties of the welds were somewhat better than with the TIG orbital process, and welding times were about 40 percent shorter

  17. Silane based coating of aluminium mold

    DEFF Research Database (Denmark)

    2013-01-01

    A method of preparing an aluminum mold for injection molding is provided, the method comprises the steps of providing an aluminum mold having a least one surface, subjecting the at least one surface to a gas or liquid phase silane to thereby form an anti-stiction coating, the anti-stiction coating...... comprising a chemically bonded monolayer of silane compounds on the at least one surface wherein the silane is a halogenated silane. The at least one surface coated with the anti-stiction coating may be configured to withstand an injection molding process at a pressure above 100 MPa. Furthermore, a mold...... having at least one closed cavity is provided, at least one surface of the at least one cavity being an aluminium surface coated with a silane based coating layer. The silane based anti-stiction coating improves the anti-stiction properties of the mold which may allow for molding and demolding of...

  18. Mechanical behaviour of aluminium-lithium alloys

    Indian Academy of Sciences (India)

    N Eswara Prasad; A A Gokhale; P Rama Rao

    2003-02-01

    Aluminium-lithium alloys hold promise of providing a breakthrough response to the crying need for lightweight alloys for use as structurals in aerospace applications. Considerable worldwide research has gone into developing a range of these alloys over the last three decades. As a result, substantial understanding has been developed of the microstructure-based micromechanisms of strengthening, of fatigue and fracture as well as of anisotropy in mechanical properties. However, these alloys have not yet greatly displaced the conventionally used denser Al alloys on account of their poorer ductility, fracture toughness and low cycle fatigue resistance. This review aims to summarise the work pertaining to study of structure and mechanical properties with a view to indicate the directions that have been and can be pursued to overcome property limitations.

  19. Experimental analysis of cut welding in aluminium

    DEFF Research Database (Denmark)

    Dorph, Pernille; De Chiffre, Leonardo; Bay, Niels

    1993-01-01

    Cut welding is a newly developed cold pressure welding process. In the present work, an experimental investigation was carried out analyzing the mechanisms involved in cut welding of a block to a strip. Experiments were carried out in technically pure aluminium. The investigation has involved...... tensile testing and metallographic investigations of the welds. The results show that this variant of cut welding is a very reproducible process giving a weld strength equal to 30-40% the strength of the parent material. The experiments have shown that the reason for this relatively low strength is an...... uneven pressure distribution along the weld due to a wave formed during sliding. Attempts to alter the material flow during sliding are presented....

  20. Adsorption of aluminium by stream particulates.

    Science.gov (United States)

    Tipping, E; Ohnstad, M; Woof, C

    1989-01-01

    An experimental study was made of the adsorption of aluminium by fine particulates from Whitray Beck, a hill stream in NW England. Adsorption increased with Al(3) activity, pH and concentration of particles, and could be quantitatively described by the empirical equation: [Formula: see text] [particles] where square brackets indicate concentrations, curly brackets, activities, and alpha, beta and gamma are constants with values of 5.14x10(-10) (mol litre(-1))(2.015) (g particles litre(-1))(-1), 0.457, and 1.472, respectively. For the experimental data, the equation gave a correlation ratio of 0.99. The equation accounts reasonably well for the adsorption of Al by particulates from seven other streams. In applying the equation, it must be borne in mind that the desorption kinetics of Al depend on pH, and rapid reversibility (or=10%) of total monomeric Al. PMID:15092454

  1. Modelling technological properties of commercial wrought aluminium alloys

    International Nuclear Information System (INIS)

    The purpose of this paper is to model three important technological properties for aluminium alloys, based on their performance indices. The models are based on the chemical compositions and microstructure characteristics which are calculated using thermodynamical calculations. The properties that were modelled are the general corrosion, the weldability (MIG and TIG) and the machinability. The results from these models are to be used in materials selection and optimisation. The models clearly show that the general corrosion resistance is reduced for all alloy additions, except for small amounts of titanium. The largest influence on the corrosion is from copper and zinc. The weldability is negatively influenced by the copper and zinc-content, and for small additions of zirconium and titanium it is increased. The machinability is positively influenced by the hardness of the alloy or by adding lead or bismuth. For the non-heat-treatable alloys there was no influence from the composition to the corrosion resistance or the weldability. Copper and zinc which are added to increase the strength to the alloy strongly reduce both the weldability and the corrosion resistance but due to the increase in hardness increase the workability.

  2. Dihydroxy-Benzenes as Corrosion Inhibitors for Aluminium Sheet in Alkali Solution

    International Nuclear Information System (INIS)

    Additions of dihydroxy-benzenes (such as catechol, hydeoquinione and resorcinol)as corrosion inhibitors decrease the corrosion of aluminium sheet (which is given in the market) in 0.1M-1.0M sodium hydroxide solutions. The decrease is dependent upon the concentration of the sodium hydroxide and that of the inhibitor. Inhibitive efficiency is resorcinol < catechol< hydroquinone< resorcinol+hydroquinone at a concentration of 0.005% (w/w) dihydroxy-benzenes, and catechol< hydroquinone< resorcinol< resorcinol+hydroquinone at 0.5%, whereas the efficiency of all three inhibitors reaches approximately 100% at a concentration of 2% inhibitors in 0.1M NaOH. No correlation appears to exist between the inhibitor efficiency and the dissociation constant (Pk values) of the inhibitor. It can be said that 0.5M concentration of sodium hydroxide is the fittest for reducing the aluminium sheet by hydroquinone and formation of catechol-aluminium complex ions in the sodium hydroxide solutions

  3. Study on optimal surface property of WC-Co cutting tool for aluminium alloy cutting

    Science.gov (United States)

    Nizar, Mohd; Arimatsu, Naoya; Kawamitsu, Hiroshi; Takai, Kazuteru; Fukumoto, Masahiro

    2016-02-01

    The light weight property as well as high corrosion resistance of aluminium alloy has increased their demand especially in automobile industries. Aluminium alloy as a matter of fact has a low melting point and high ductility that severely adhere to the cutting tool surface and cause deterioration of chip evacuation. This problem often resulting in tools breakage. In this paper, in order to impart functions of anti-adhesion, we propose a technique by controlling the grinding marks micro texture on the tool surface by using the blast polishing treatment without any coating technologies. The results show that the tool which underwent polishing treatment reduces the cutting force as well as the aluminium adherence during the initial cutting process, and become worst as the process cutting continues. These results indicate that grinding mark texture improves the anti-adhesion by reducing the contact area during cutting and provide storage for the lubricant. In addition, too much polishing on the tool surface may remove these textures and resultantly worsen the tool performance.

  4. Fires in storages of LFO: Analysis of hazard of structural collapse of steel-aluminium containers.

    Science.gov (United States)

    Rebec, A; Kolšek, J; Plešec, P

    2016-04-01

    Pool fires of light fuel oil (LFO) in above-ground storages with steel-aluminium containers are discussed. A model is developed for assessments of risks of between-tank fire spread. Radiative effects of the flame body are accounted for by a solid flame radiation model. Thermal profiles evolved due to fire in the adjacent tanks and their consequential structural response is pursued in an exact (materially and geometrically non-linear) manner. The model's derivation is demonstrated on the LFO tank storage located near the Port of Koper (Slovenia). In support of the model, data from literature are adopted where appropriate. Analytical expressions are derived correspondingly for calculations of emissive characteristics of LFO pool fires. Additional data are collected from experiments. Fire experiments conducted on 300cm diameter LFO pans and at different wind speeds and high-temperature uniaxial tension tests of the analysed aluminium alloys types 3xxx and 6xxx are presented. The model is of an immediate fire engineering practical value (risk analyses) or can be used for further research purposes (e.g. sensitivity and parametric studies). The latter use is demonstrated in the final part of the paper discussing possible effects of high-temperature creep of 3xxx aluminium. PMID:26802486

  5. Effect of Manganese on the Mechanical Properties of Welded As-Cast Aluminium Joint

    Directory of Open Access Journals (Sweden)

    Isiaka Oluwole OLADELE

    2013-11-01

    Full Text Available The effects of manganese on the mechanical properties of welded and un-weld as-cast 6063 aluminium alloy has been studied. Alloys of varying percentage of manganese from 0.019 to 0.24 were sand cast. A wooden pattern of dimensions 200×100×100mm was used, the aluminium (500g was charged into an induction furnace and heated to 750°C for 15 minutes, this was followed by the addition of weighed powdered manganese, stirred and heated at the same temperature for another 5 minutes and thereafter poured into the already prepared sand mould at a temperature of 690°C. The as-cast aluminium samples, were sectioned into two equal parts of 45mm each using power hack saw; a weld groove was created between the sides of the samples using an electric hand grinding machine, the groove served as the path along which the filler metal was deposited on the aluminium, a single v butt joint was produced from each sample and Metal Inert Gas Welding process was carried out to produce the required joint design. The different cast samples were machined to the different test pieces after which they were assessed to determine their mechanical properties (impact, hardness (welded joint and heat affected zone and tensile tests. The microstructures of the welded samples were also studied. From the results, it was observed that Sample F, which has 0.172% Mn, has the best hardness and impact strength while sample C with 0.160% Mn has the highest ultimate tensile strength.

  6. Aluminium leaching from red mud by filamentous fungi.

    Science.gov (United States)

    Urík, Martin; Bujdoš, Marek; Milová-Žiaková, Barbora; Mikušová, Petra; Slovák, Marek; Matúš, Peter

    2015-11-01

    This contribution investigates the efficient and environmentally friendly aluminium leaching from red mud (bauxite residue) by 17 species of filamentous fungi. Bioleaching experiments were examined in batch cultures with the red mud in static, 7-day cultivation. The most efficient fungal strains in aluminium bioleaching were Penicillium crustosum G-140 and Aspergillus niger G-10. The A. niger G-10 strain was capable to extract up to approximately 141 mg·L(-1) of aluminium from 0.2 g dry weight red mud. Chemical leaching with organic acids mixture, prepared according to A. niger G-10 strain's respective fungal excretion during cultivation, proved that organic acids significantly contribute to aluminium solubilization from red mud. PMID:26365318

  7. Corrosion of spent nuclear fuel aluminium cladding in ordinary water

    International Nuclear Information System (INIS)

    Corrosion of aluminium alloy cladding of spent nuclear fuel elements in ordinary water is examined in the spent fuel storage pool of the RA research reactor at the Vinca Institute of Nuclear Sciences, Belgrade, Serbia and Montenegro. Experimental examinations are carried out within framework of the International Atomic Energy Agency (IAEA) Coordinated Research Project (CRP) 'Corrosion of Research Reactor Aluminium-Clad Spent Fuel in Water', Phase II. Racks with coupons made of different aluminium alloys were exposed to water influence for period of six months to six years. The project comprises also activities on monitoring of the water chemistry and radioactivity in the storage pool. Visual and microscopic examinations of surfaces of aluminium coupons of the test racks have been done recently and results were presented in this paper confirming strong influence of water quality and exposition time to corrosion process. (author)

  8. Deposition of aluminium nanoparticles using dense plasma focus device

    International Nuclear Information System (INIS)

    Plasma route to nanofabrication has drawn much attention recently. The dense plasma focus (DPF) device is used for depositing aluminium nanoparticles on n-type Si (111) wafer. The plasma chamber is filled with argon gas and evacuated at a pressure of 80 Pa. The substrate is placed at distances 4.0 cm, 5.0 cm and 6.0 cm from the top of the central anode. The aluminium is deposited on Si wafer at room temperature with two focused DPF shots. The deposits on the substrate are examined for their morphological properties using atomic force microscopy (AFM). The AFM images have shown the formation of aluminium nanoparticles. From the AFM images, it is found that the size of aluminium nanoparticles increases with increase in distance between the top of anode and the substrate for same number of DPF shots.

  9. Aluminium foam sandwich panels: manufacture, metallurgy and applications

    Energy Technology Data Exchange (ETDEWEB)

    Banhart, J. [Hahn-Meitner-Institut, TU Berlin (Germany); Seeliger, H.W. [Alm GmbH, Saarbruecken (Germany)

    2008-09-15

    Sandwich panels consisting of a highly porous aluminium foam core and aluminium alloy face sheets are manufactured by roll-bonding aluminium alloy sheets to a densified mixture of metal powders - usually Al-Si or Al-Si-Cu alloys with 6-8% Si and 3-10% Cu - and titanium hydride, and foaming the resulting three-layer structure by a thermal treatment. We review the various processing steps of aluminium foam sandwich (AFS) and the metallurgical processes during foaming, compare the process to alternative ways to manufacture AFS, e.g. by adhesive bonding, and give an overview of the available literature. Two ways to treat AFS after foaming are presented, namely forging and age-hardening. Some current and potential applications are described and the market potential of AFS is assessed. (Abstract Copyright [2008], Wiley Periodicals, Inc.)

  10. Aluminium trihydroxide in combination with ammonium polyphosphate as flame retardants for unsaturated polyester resin

    Directory of Open Access Journals (Sweden)

    2009-11-01

    Full Text Available The thermal and reaction to fire characteristics of a flame retardant unsaturated polyester (UP ternary system are presented here. Thermal gravimetric analysis showed an improved thermal stability between 200–600°C with the addition of ammonium polyphosphate (APP and aluminium trihydroxide (ATH formulation. Cone calorimetry tests indicated that ATH is more efficient than calcium carbonate at delaying the ignition time, lowering the carbon monoxide yield and lowering the peak heat release (PHRR. However the addition of APP and ATH to the formulation failed to demonstrate any significant synergistic effect at reducing the PHRR.

  11. Local electrochemical behaviour of 7xxx aluminium alloys

    OpenAIRE

    F. Andreatta

    2004-01-01

    Aluminium alloys of the 7xxx series (Al-Zn-Mg-Cu) are susceptible to localized types of corrosion like pitting, intergranular corrosion and exfoliation corrosion. This represents a limitation for the application of these alloys in the aerospace components because localized corrosion might have a negative effect on safety and costs. This PhD thesis investigates the relation between electrochemical behaviour and microstructure of a number of 7xxx aluminium alloys: AA7075, AA7349 and an experime...

  12. Crushing modes of aluminium tubes under axial compression

    OpenAIRE

    Pled, Florent; Yan, Wenyi; Wen, Cui'e

    2014-01-01

    6 pages International audience A numerical study of the crushing of circular aluminium tubes with and without aluminium foam fillers has been carried out to investigate their buckling behaviours under axial compression. A crushing mode classification chart has been established for empty tubes. The influence of boundary conditions on crushing mode has also been investigated. The effect of foam filler on the crushing mode of tubes filled with foam was then examined. The predicted results ...

  13. Adhesive Bonding of Aluminium Alloy A5754 by Epoxy Resins

    Directory of Open Access Journals (Sweden)

    Ivan Michalec

    2013-01-01

    Full Text Available Joining thin sheets of aluminium and its alloys is a promising area in the field of joining materials. Nowadays, joining methods that do not melt the material itself are increasingly being utilised. This paper deals with adhesive bonding of aluminium alloy A5754 by two-component epoxy resins. Theresults show that joints bonded by Hysol 9466 have appropriate mechanical properties, but that joints bonded by Hysol 9492 have better thermal stability.

  14. Modeling of aluminium deposition from chloroaluminate ionic liquids

    OpenAIRE

    Schaltin, Stijn; Ganapathi, Murugan; Binnemans, Koen; Fransaer, Jan

    2011-01-01

    A finite-element model of the electrodeposition of aluminium from chloroaluminate ionic liquids is introduced. The purpose of this model is to give an explanation for the reasonable current densities that can be achieved in chloroaluminate ionic liquids despite the fact that the electrochemically active Al2Cl7- complexes are transformed into inactive AlCl4- complexes during the electrodeposition of aluminium. The obtainable current density in the electrodeposition from chloroaluminate ionic l...

  15. TORSIONAL DEFORMATION AND FATIGUE BEHAVIOUR OF 6061 ALUMINIUM ALLOY

    OpenAIRE

    Marini Marno; Ahmad Badri Ismail

    2012-01-01

    Torsional deformation and fatigue behaviour of both solid and thin-walled tubular specimens were made from as-received and heat treated 6061 aluminium alloy were studied. 6061 aluminium alloy have been widely used as a candidate material in automobile, aerospace, aircraft and structural application because of their superior mechanical properties such as high strength to weight ratio, good ductility and others. The differences in cyclic deformation and fatigue behaviours between round and soli...

  16. Ball Pad Mold Electromagnetic Forming Process for Aluminium Alloy Sheet

    OpenAIRE

    Wang, Wen-ping; Wu, Xiang-Dong; Wan, Min; Chen, Xiao-wei; Xiong, Wei-Ren

    2014-01-01

    In order to meet requirements of lightweight technology in the field of aerospace, the new forming technology for aluminium alloy skin parts and integral panel are brought to more attention. Based on the principle of electromagnetic forming (EMF) and energy distribution, a new electromagnetic forming process using ball as pad mold for aluminium alloy sheet forming was suggested and test apparatus was designed. The new method was verified by the finite element simulation and exp...

  17. Blast Loaded Aluminium Plates : Experiments and numerical simulations

    OpenAIRE

    Melby, Emil Arne; Eide, Hilde Olaug Stakvik

    2013-01-01

    Light and flexible protective constructions in aluminium could be subjected to a blast load. In this thesis the effect of blast loading on aluminium plates of the type 1050A ? H14 was studied through experiments and numerical simulations. The effect of fragmentation was idealized with predrilled holes. The thesis was written at the Structural Impact Laboratory (SIMLab) at NTNU in collaboration with the Norwegian Defence Estates Agency (NDEA).Tensile tests revealed a clearly anisotropic behavi...

  18. Adhesive Bonding of Aluminium Alloy A5754 by Epoxy Resins

    OpenAIRE

    Ivan Michalec; Milan Marônek

    2013-01-01

    Joining thin sheets of aluminium and its alloys is a promising area in the field of joining materials. Nowadays, joining methods that do not melt the material itself are increasingly being utilised. This paper deals with adhesive bonding of aluminium alloy A5754 by two-component epoxy resins. Theresults show that joints bonded by Hysol 9466 have appropriate mechanical properties, but that joints bonded by Hysol 9492 have better thermal stability.

  19. Prevention of Dealloying in Manganese Aluminium Bronze Propeller: Part II

    OpenAIRE

    Napachat Tareelap; Kaysinee Sriraksasin; Nakorn Srisukhumbowornchai; Swieng Thuanboon; Choochat Nitipanyawong

    2014-01-01

    Due to the failure of manganese aluminium bronze (MAB) propeller caused by dealloying corrosion as described in Part I [1], this work aims to study the prevention of dealloying corrosion using aluminium and zinc sacrificial anodes. The results indicated that both of the sacrificial anodes could prevent the propeller from dealloying. Moreover, the dealloying in seawater was less than that found in brackish water. It was possible that hydroxide ions, from cathodic reaction, reacted with calcium...

  20. Crystallographic orientation-spray formed hypereutectic aluminium-silicon alloys

    OpenAIRE

    Hamilta de Oliveira Santos; Marilene Morelli Serna; Nelson Batista de Lima; Isolda Costa; Jesualdo Luiz Rossi

    2005-01-01

    Aluminium-silicon alloys have been wide accepted in the automotive, electric and aerospace industries. Preferred orientation is a very common condition for metals and alloys. Particularly, aluminium induces texture during the forming process. The preparation of an aggregate with completely random crystal orientation is a difficult task. The present work was undertaken to analyse the texture by X-ray diffraction techniques, of three spray formed hypereutectic Al-Si alloys. Samples were taken f...

  1. Volatilisation and oxidation of aluminium scraps fed into incineration furnaces.

    Science.gov (United States)

    Biganzoli, Laura; Gorla, Leopoldo; Nessi, Simone; Grosso, Mario

    2012-12-01

    Ferrous and non-ferrous metal scraps are increasingly recovered from municipal solid waste incineration bottom ash and used in the production of secondary steel and aluminium. However, during the incineration process, metal scraps contained in the waste undergo volatilisation and oxidation processes, which determine a loss of their recoverable mass. The present paper evaluates the behaviour of different types of aluminium packaging materials in a full-scale waste to energy plant during standard operation. Their partitioning and oxidation level in the residues of the incineration process are evaluated, together with the amount of potentially recoverable aluminium. About 80% of post-consumer cans, 51% of trays and 27% of foils can be recovered through an advanced treatment of bottom ash combined with a melting process in the saline furnace for the production of secondary aluminium. The residual amount of aluminium concentrates in the fly ash or in the fine fraction of the bottom ash and its recovery is virtually impossible using the current eddy current separation technology. The average oxidation levels of the aluminium in the residues of the incineration process is equal to 9.2% for cans, 17.4% for trays and 58.8% for foils. The differences between the tested packaging materials are related to their thickness, mechanical strength and to the alloy. PMID:22749723

  2. Surface roughness when diamond turning RSA 905 optical aluminium

    Science.gov (United States)

    Otieno, T.; Abou-El-Hossein, K.; Hsu, W. Y.; Cheng, Y. C.; Mkoko, Z.

    2015-08-01

    Ultra-high precision machining is used intensively in the photonics industry for the production of various optical components. Aluminium alloys have proven to be advantageous and are most commonly used over other materials to make various optical components. Recently, the increasing demand from optical systems for optical aluminium with consistent material properties has led to the development of newly modified grades of aluminium alloys produced by rapid solidification in the foundry process. These new aluminium grades are characterised by their finer microstructures and refined mechanical and physical properties. However the machining database of these new optical aluminium grades is limited and more research is still required to investigate their machinability performance when they are diamond turned in ultrahigh precision manufacturing environment. This work investigates the machinability of rapidly solidified aluminium RSA 905 by varying a number of diamond-turning cutting parameters and measuring the surface roughness over a cutting distance of 4 km. The machining parameters varied in this study were the cutting speed, feed rate and depth of cut. The results showed a common trend of decrease in surface roughness with increasing cutting distance. The lowest surface roughness Ra result obtained after 4 km in this study was 3.2 nm. This roughness values was achieved using a cutting speed of 1750 rpm, feed rate of 5 mm/min and depth of cut equal to 25 μm.

  3. Effects of surface treatment of aluminium alloy 1050 on the adhesion and anticorrosion properties of the epoxy coating

    Energy Technology Data Exchange (ETDEWEB)

    Sharifi Golru, S., E-mail: samanesharifi@aut.ac.ir [Department of Polymer Engineering and Color Technology, Amirkabir University of Technology, P.O. Box 15875-4413 Tehran (Iran, Islamic Republic of); Attar, M.M., E-mail: attar@aut.ac.ir [Department of Polymer Engineering and Color Technology, Amirkabir University of Technology, P.O. Box 15875-4413 Tehran (Iran, Islamic Republic of); Ramezanzadeh, B. [Department of Surface Coating and Corrosion, Institute for Color Science and Technology, No. 59,Vafamanesh St, Hosainabad Sq, Lavizan, Tehran (Iran, Islamic Republic of)

    2015-08-01

    Highlights: • Aluminium alloy 1050 was treated by zirconium-based (Zr) conversion coating. • The surface morphology and surface free energy of the samples were obtained. • The adhesion properties of the epoxy coating was studied on the treated samples. • The corrosion resistance of the epoxy coating was enhanced on treated samples. - Abstract: The objective of this work is to investigate the effects of zirconium-based (Zr) conversion coating on the adhesion properties and corrosion resistance of an epoxy/polyamide coating applied on the aluminium alloy 1050 (AA1050). Field emission scanning electron microscope (FE-SEM), energy dispersive X-ray spectrum (EDS), atomic force microscope (AFM) and contact angle measuring device were employed in order to characterize the surface characteristics of the Zr treated AA1050 samples. The epoxy/polyamide coating was applied on the untreated and Zr treated samples. The epoxy coating adhesion to the aluminium substrate was evaluated by pull-off test before and after 30 days immersion in 3.5% w/w NaCl solution. In addition, the electrochemical impedance spectroscopy (EIS) and salt spray tests were employed to characterize the corrosion protection properties of the epoxy coating applied on the AA1050 samples. Results revealed that the surface treatment of AA1050 by zirconium conversion coating resulted in the increase of surface free energy and surface roughness. The dry and recovery (adhesion strength after 30 days immersion in the 3.5 wt% NaCl solution) adhesion strengths of the coatings applied on the Zr treated aluminium samples were greater than untreated sample. In addition, the adhesion loss of the coating applied on the Zr treated aluminium substrate was lower than other samples. Also, the results obtained from EIS and salt spray test clearly revealed that the Zr conversion coating could enhance the corrosion protective performance of the epoxy coating significantly.

  4. Effects of surface treatment of aluminium alloy 1050 on the adhesion and anticorrosion properties of the epoxy coating

    International Nuclear Information System (INIS)

    Highlights: • Aluminium alloy 1050 was treated by zirconium-based (Zr) conversion coating. • The surface morphology and surface free energy of the samples were obtained. • The adhesion properties of the epoxy coating was studied on the treated samples. • The corrosion resistance of the epoxy coating was enhanced on treated samples. - Abstract: The objective of this work is to investigate the effects of zirconium-based (Zr) conversion coating on the adhesion properties and corrosion resistance of an epoxy/polyamide coating applied on the aluminium alloy 1050 (AA1050). Field emission scanning electron microscope (FE-SEM), energy dispersive X-ray spectrum (EDS), atomic force microscope (AFM) and contact angle measuring device were employed in order to characterize the surface characteristics of the Zr treated AA1050 samples. The epoxy/polyamide coating was applied on the untreated and Zr treated samples. The epoxy coating adhesion to the aluminium substrate was evaluated by pull-off test before and after 30 days immersion in 3.5% w/w NaCl solution. In addition, the electrochemical impedance spectroscopy (EIS) and salt spray tests were employed to characterize the corrosion protection properties of the epoxy coating applied on the AA1050 samples. Results revealed that the surface treatment of AA1050 by zirconium conversion coating resulted in the increase of surface free energy and surface roughness. The dry and recovery (adhesion strength after 30 days immersion in the 3.5 wt% NaCl solution) adhesion strengths of the coatings applied on the Zr treated aluminium samples were greater than untreated sample. In addition, the adhesion loss of the coating applied on the Zr treated aluminium substrate was lower than other samples. Also, the results obtained from EIS and salt spray test clearly revealed that the Zr conversion coating could enhance the corrosion protective performance of the epoxy coating significantly

  5. Ameliorating Effect of Ginger Extract (Zingiber officinale Roscoe on Liver Marker Enzymes, Lipid Profile in Aluminium chloride Induced Male Rats

    Directory of Open Access Journals (Sweden)

    A Kalaiselvi

    2015-01-01

    Full Text Available Nowadays, aluminium (Al exposure has been increasing and it has the potential to be toxic in animal and humans. In recent years, ginger has become a subject of interest because of its beneficial effects on human health. The purpose of the present study to investigate the effect of ginger extract on serum biochemical parameters of aluminium chloride (AlCl3 induced male rats. 24 Wistar rats (6 in each group distributed into 4 groups. Control group received distilled water as vehicle; In E1 group, animal received AlCl3 orally (100 mg/kg bw, E2 group received AlCl3 (100 mg/kg bw and simultaneously with ginger extract (50 mg/kg bw and E3 group received ginger extract alone (50 mg/kg bw for 60 days. At the end of the experimental period, blood samples were collected for separating the serum for biochemical analyses. The results showed that oral administration of aluminium revealed a significant increase in the levels of serum glucose, total protein, globulin, albumin, urea, uric acid, creatinine, lipid profile and serum aspartate aminotransferase (AST, alanine aminotransferase (ALT and alkaline phosphatase (ALP and no change was noted in bilirubin. The extract of ginger decreased the activities serum levels of AST, ALT, ALP, lipid profile and all the parameter studied. It was concluded that the consumption of ginger protects the liver and kidney against the Aluminium toxicity. In addition, ginger is capable of improving hyperlipidemia and the impaired kidney functions.

  6. Intergranular precipitation in aluminium-copper oriented bi-crystals

    International Nuclear Information System (INIS)

    In the first part of this research thesis, the author addresses the fabrication of aluminium-copper oriented bi-crystals by discussing the specific problems raised by this fabrication, and by describing the aspect after a thermal treatment chosen to reach a defined objective: the visibility of precipitates in all grain boundaries, and a secondary role of kinetic parameters. The second part addresses the density of intergranular precipitates by reporting and commenting the results of precipitate numbering in symmetric and asymmetric boundaries performed by using optic microscopy. The third part addresses the dimensions and shapes of intergranular precipitates. The author there reports the study of the average dimensions of precipitates with respect to boundary nature. Some additional remarks are made regarding their shape and crystallographic nature. Numerical results are obtained from measurements performed on photographs of carbon replicates taken by using an electronic microscope. The author then reports the study of the width of the area of low precipitation density at the edge of boundaries. A copper assessment in the intergranular band is performed which shows the type of relationship which seems to exist between previously studied phenomena. Finally, the author reports the study of the relationship between boundary atomic structure and intergranular precipitation. A grain boundary model has been developed and allows a definition of intergranular germination sites to be obtained

  7. Irradiation effects on aluminium and beryllium

    International Nuclear Information System (INIS)

    The High Flux Reactor (HFR) in Petten (The Netherlands) is a 45 MW light water cooled and moderated research reactor. The vessel was replaced in 1984 after more than 20 years of operation because doubts had arisen over the condition of the aluminium alloy construction material. Data on the mechanical properties of the aluminium alloy Al 5154 with and without neutron irradiation are necessary for the safety analysis of the new HFR vessel which is constructed from the same material as the old vessel. Fatigue, fracture mechanics (crack growth and fracture toughness) and tensile properties have been obtained from several experimental testing programmes with materials of the new and the old HFR vessel. 1) Low-cycle fatigue testing has been carried out on non-irradiated specimens from stock material of the new HFR vessel. The number of cycles to failure ranges from 90 to more than 50,000 for applied strain from 3.0% to 0.4%; 2) Fatigue crack growth rate testing has been conducted: - with unirradiated specimens from stock material of the new vessel; - with irradiated specimens from the remnants of the old core box. Irradiation has a minor effect on the sub-critical fatigue crack growth rate. The ultimate increase of the mean crack growth rate amounts to a factor of 2. However crack extension is strongly reduced due to the smaller crack length for crack growth instability (reduction of KIC). - Irradiated material from the core box walls of the old vessel has been used for fracture toughness testing. The conditional fracture toughness values KIQ ranges from 30.3 down to 16.5 MPa√m. The lowermost meaningful 'KIC' is 17.7 MPa√m corresponding to the thermal fluence of 7.5 1026 n/m2 for the End of Life (EOL) of the old vessel. - Testing carried out on irradiated material from the remnants of the old HFR core box shows an ultimate neutron irradiation hardening of 35 points increase of HSR15N and an ultimate tensile yield stress of 589 MPa corresponding to the ductility of 1

  8. Synthesis and characterisation of closed cells aluminium foams containing dolomite powder as foaming agent: Priprava in karakterizacija aluminijskih pen z zaprto poroznostjo, izdelanih z dolomitnim prahom kot sredstvom za penjenje:

    OpenAIRE

    JENKO, Monika; Kevorkijan, Varužan; Paulin, Irena; Škapin, Srečo D.; Šuštaršič, Borivoj

    2010-01-01

    In this work, the viability of dolomite powder as cost-effective alternative to TiHsub2 foaming agent was investigated. Closed cells aluminium foam samples were prepared starts from solid, foamable precursors synthesized by powder metallurgy and melt route. Precursors obtained by melt route were machined and additional cold isostatic pressed in order to improve their density. In allcases, the resulted precursors consisted of an aluminium matrix containing various mass fractions of uniformly d...

  9. Bioaccumulation of Aluminium in Hydromacrophytes in Polish Coastal Lakes

    Directory of Open Access Journals (Sweden)

    Senze Magdalena

    2015-03-01

    Full Text Available The research on aluminium content was conducted in water and on aquatic flora of Polish lakes in the central part of the coast. The study included the lakes Sarbsko, Choczewskie, Bia.e, K.odno, D.brze and Salino investigated in the summer of 2013. The examined lakes belong mainly to the direct basin of the Baltic Sea. Samples of aquatic plants and lake waters were collected. In the water samples pH and electrolytic conductivity were measured. The aluminium content was determined both in water and aquatic plants. Submerged hydromacrophyte studies included Myriophyllum alterniflorum L., Potamogeton perfoliatus L. and Ceratophyllum demersum L. Emergent hydromacrophyte studies included Phragmites australis (Cav. Trin. ex Steud., Juncus bulbosus L., Iris pseudacorus L., Eleocharis palustris (L. Roem. % Schult., Phalaris arundinacea L., Carex riparia Curt., Mentha aquatic L., Stratiotes aloides L., Alisma plantago-aquatica L., Glyceria maxima (Hartman Holmb., Sagittaria sagittifolia L., Scirpus lacustris L. and Typha angustifolia L. The purpose of this investigation was the determination of the aluminium content in submerged and emergent hydromacrophytes and also the definition of their bioaccumulative abilities. The average concentration of aluminium in water was 2.68 fęg Al dm.3. The average content of aluminium in plants was 2.8015 mg Al kg.1. The bioaccumulation factor ranged from BCF=19.74 to BCF=16619. On the basis of the analysis of the aluminium content in water and aquatic plants results show that both water and plants were characterized by a moderate level of aluminium. The recorded concentrations indicate a mid-range value and are much lower than those which are quoted for a variety of surface waters in various parts of the world.

  10. Oxidation of φ'-aluminium oxynitride

    International Nuclear Information System (INIS)

    Research highlights: Oxidation of φ'-AlON has been studied for the first time. First corrosion products are γ-alumina. Low density α-alumina is formed at high temperature. Grains are extensively cracked after oxidation. The low density of the α-alumina is due to a network of nanometric porosities. - Abstract: The oxidation in air of single crystal φ'-aluminium oxynitride (AlON) grains has been characterized by thermogravimetry and X-ray diffraction in the 1273-1673 K range. Two oxidation stages have been observed, suggesting the formation of a transitional phase. Below 1473 K, oxidation results in the apparition of platelets and noodle-like crystals on the surface of the initially faceted single crystals. Above 1473 K, low density α-alumina polycrystals start forming on the grain surface and grow towards the grain core with increasing temperature or time. Their low density is mainly due to the presence of a network of nano-porosities.

  11. A systematic review of aluminium phosphide poisoning.

    Science.gov (United States)

    Mehrpour, Omid; Jafarzadeh, Mostafa; Abdollahi, Mohammad

    2012-03-01

    Every year, about 300,000 people die because of pesticide poisoning worldwide. The most common pesticide agents are organophosphates and phosphides, aluminium phosphide (AlP) in particular. AlP is known as a suicide poison that can easily be bought and has no effective antidote. Its toxicity results from the release of phosphine gas as the tablet gets into contact with moisture. Phosphine gas primarily affects the heart, lungs, gastrointestinal tract, and kidneys. Poisoning signs and symptoms include nausea, vomiting, restlessness, abdominal pain, palpitation, refractory shock, cardiac arrhythmias, pulmonary oedema, dyspnoea, cyanosis, and sensory alterations. Diagnosis is based on clinical suspicion, positive silver nitrate paper test to phosphine, and gastric aspirate and viscera biochemistry. Treatment includes early gastric lavage with potassium permanganate or a combination with coconut oil and sodium bicarbonate, administration of charcoal, and palliative care. Specific therapy includes intravenous magnesium sulphate and oral coconut oil. Moreover, acidosis can be treated with early intravenous administration of sodium bicarbonate, cardiogenic shock with fluid, vasopresor, and refractory cardiogenic shock with intra-aortic baloon pump or digoxin. Trimetazidine may also have a useful role in the treatment, because it can stop ventricular ectopic beats and bigeminy and preserve oxidative metabolism. This article reviews the epidemiological, toxicological, and clinical/pathological aspects of AlP poisoning and its management. PMID:22450207

  12. Eu(III)-doped aluminium yttrium oxide

    International Nuclear Information System (INIS)

    In this work, we report the synthesis and the photoluminescence features of Eu(III)-doped yttrium-aluminium oxide obtained by non-hydrolytic sol-gel routes. After heating the powders above 600 deg C the XRD patterns show the presence of the Y4Al2O9 (YAM) and Y3Al5O12 (YAG) phases. At 800 and at 1500 deg C the PL spectra display the Eu(III) lines characteristic of the YAM monoclinic phase. The 5D0→7F2 transition is favored relatively to the 5D0→7F1 lines. However, at 1100 deg C the cubic YAG is the preferential phase and the 5D0→7F1 transition dominates the spectrum. The Eu(III) ions lie in a centro symmetrical site. The different solvents used in the sol-gel synthesis also change the relative proportion between these two phases. This is monitored analyzing the modifications in the relative intensity between the 5D0→7F2 and the 5D0→7F1 transitions. (author)

  13. Anomalous Diffusion of Mo Implanted into Aluminium

    Institute of Scientific and Technical Information of China (English)

    张通和; 吴瑜光; 邓志威; 钱卫东

    2001-01-01

    Mo ions are implanted into aluminium with a high ion flux and high dose at elevated temperatures of 300℃, 400℃ and 500℃ . X-ray diffraction spectra show that the Al12Mo phases are formed. Rutherford backscattering spectroscopy indicates that a profile of Mo appears in Al around the depth of 550nm and with an atomic concentration of ~7%, when Mo is implanted to the dose of 3 × 1017/cm2 with an ion flux of 45μA/cm2 (400℃).If the dose increases to 1 × 1018/cm2 at the same ion flux, the penetration of Mo ions in Al can reach a depth of 2μm, which is greater than the ion project range Rp (52.5nm). The results show that anomalous diffusion takes place. Owing to the intense atom collision cascades, the diffusion coefficient increases greatly with the increase of the ion flux and dose. The Mo diffusion coefficients in Al are calculated. The Mo retained dose in A1 increases obviously with the increase of the ion flux.

  14. Acute aluminium phosphide poisoning, what is new?

    Directory of Open Access Journals (Sweden)

    Yatendra Singh

    2014-01-01

    Full Text Available Aluminium phosphide (AlP is a cheap solid fumigant and a highly toxic pesticide that is commonly used for grain preservation. AlP has currently generated interest with increasing number of cases in the past four decades because of its increased use for agricultural and nonagricultural purposes, and also its easy availability in the markets has led to its increased misuse to commit suicide. Ingestion is usually suicidal in intent, uncommonly accidental and rarely homicidal. The poison affects all systems, shock, cardiac arrhythmias with varied ECG changes and gastrointestinal features being the most prominent. Diagnosis is made on the basis of clinical suspicion, a positive silver nitrate paper test to phosphine, and gastric aspirate and viscera biochemistry. Treatment includes early gastric lavage with potassium permanganate or a combination of coconut oil and sodium bicarbonate, administration of charcoal and palliative care. Specific therapy includes intravenous magnesium sulphate and oral coconut oil. Unfortunately, the lack of a specific antidote Results in very high mortality and the key to treatment lies in rapid decontamination and institution of resuscitative measures. This article aims to identify the salient features and mechanism of AlP poisoning along with its management strategies and prognostic variables.

  15. Fuzzy Multicriteria Ranking of Aluminium Coating Methods

    Science.gov (United States)

    Batzias, A. F.

    2007-12-01

    This work deals with multicriteria ranking of aluminium coating methods. The alternatives used are: sulfuric acid anodization, A1; oxalic acid anodization, A2; chromic acid anodization, A3; phosphoric acid anodization, A4; integral color anodizing, A5; chemical conversion coating, A6; electrostatic powder deposition, A7. The criteria used are: cost of production, f1; environmental friendliness of production process, f2; appearance (texture), f3; reflectivity, f4; response to coloring, f5; corrosion resistance, f6; abrasion resistance, f7; fatigue resistance, f8. Five experts coming from relevant industrial units set grades to the criteria vector and the preference matrix according to a properly modified Delphi method. Sensitivity analysis of the ranked first alternative A1 against the `second best', which was A3 at low and A7 at high resolution levels proved that the solution is robust. The dependence of anodized products quality on upstream processes is presented and the impact of energy price increase on industrial cost is discussed.

  16. Aluminium Matrix Composites Reinforced with Co-continuous Interlaced Phases Aluminium-alumina Needles

    Directory of Open Access Journals (Sweden)

    Elvio de Napole Gregolin

    2002-09-01

    Full Text Available An Al-5SiO2 (5 wt% of SiO2 aluminium matrix fiber composite was produced where the reinforcement consists of fossil silica fibers needles. After being heat-treated at 600 °C, the original fiber morphology was retained but its microstructure changed from solid silica to an interconnected (Al-Si/Al2O3 interlaced structure named co-continuous composite. A technique of powder metallurgy, using commercial aluminium powder and the silica fibers as starting materials, followed by hot extrusion, was used to produce the composite. The co-continuous microstructure was obtained partially or totally on the fibers as a result of the reaction, which occurs during the heat treatment, first by solid diffusion and finally by the liquid Al-Si in local equilibrium, formed with the silicon released by reaction. The internal structure of the fibers was characterized using field emission electron microscope (FEG-SEM and optical microscopy on polished and fractured samples.

  17. Enhancement of wear and ballistic resistance of armour grade AA7075 aluminium alloy using friction stir processing

    Directory of Open Access Journals (Sweden)

    I. Sudhakar

    2015-03-01

    Full Text Available Industrial applications of aluminium and its alloys are restricted because of their poor tribological properties. Thermal spraying, laser surfacing, electron beam welding are the most widely used techniques to alter the surface morphology of base metal. Preliminary studies reveal that the coating and layering of aluminium alloys with ceramic particles enhance the ballistic resistance. Furthermore, among aluminium alloys, 7075 aluminium alloy exhibits high strength which can be compared to that of steels and has profound applications in the designing of lightweight fortification structures and integrated protection systems. Having limitations such as poor bond integrity, formation of detrimental phases and interfacial reaction between reinforcement and substrate using fusion route to deposit hard particles paves the way to adopt friction stir processing for fabricating surface composites using different sizes of boron carbide particles as reinforcement on armour grade 7075 aluminium alloy as matrix in the present investigation. Wear and ballistic tests were carried out to assess the performance of friction stir processed AA7075 alloy. Significant improvement in wear resistance of friction stir processed surface composites is attributed to the change in wear mechanism from abrasion to adhesion. It has also been observed that the surface metal matrix composites have shown better ballistic resistance compared to the substrate AA7075 alloy. Addition of solid lubricant MoS2 has reduced the depth of penetration of the projectile to half that of base metal AA7075 alloy. For the first time, the friction stir processing technique was successfully used to improve the wear and ballistic resistances of armour grade high strength AA7075 alloy.

  18. Enhancement of wear and ballistic resistance of armour grade AA7075 aluminium alloy using friction stir processing

    Institute of Scientific and Technical Information of China (English)

    I. SUDHAKAR; V. MADHU; G. MADHUSUDHAN REDDY; K. SRINIVASA RAO

    2015-01-01

    Industrial applications of aluminium and its alloys are restricted because of their poor tribological properties. Thermal spraying, laser surfacing, electron beam welding are the most widely used techniques to alter the surface morphology of base metal. Preliminary studies reveal that the coating and layering of aluminium alloys with ceramic particles enhance the ballistic resistance. Furthermore, among aluminium alloys, 7075 aluminium alloy exhibits high strength which can be compared to that of steels and has profound applications in the designing of lightweight fortification structures and integrated protection systems. Having limitations such as poor bond integrity, formation of detrimental phases and interfacial reaction between reinforcement and substrate using fusion route to deposit hard particles paves the way to adopt friction stir processing for fabricating surface composites using different sizes of boron carbide particles as reinforcement on armour grade 7075 aluminium alloy as matrix in the present investigation. Wear and ballistic tests were carried out to assess the performance of friction stir processed AA7075 alloy. Significant improvement in wear resistance of friction stir processed surface composites is attributed to the change in wear mechanism from abrasion to adhesion. It has also been observed that the surface metal matrix composites have shown better ballistic resistance compared to the substrate AA7075 alloy. Addition of solid lubricant MoS2 has reduced the depth of penetration of the projectile to half that of base metal AA7075 alloy. For the first time, the friction stir processing technique was successfully used to improve the wear and ballistic resistances of armour grade high strength AA7075 alloy.

  19. Evaluation of certain food additives and contaminants. Eightieth report of the Joint FAO/WHO Expert Committee on Food Additives.

    Science.gov (United States)

    2016-01-01

    This report represents the conclusions of a Joint FAO/WHO Expert Committee convened to evaluate the safety of various food additives and contaminants and to prepare specifications for identity and purity. The first part of the report contains a brief description of general considerations addressed at the meeting, including updates on matters of interest to the work of the Committee. A summary follows of the Committee's evaluations of technical, toxicological and/or dietary exposure data for seven food additives (benzoates; lipase from Fusarium heterosporum expressed in Ogataea polymorpha; magnesium stearate; maltotetraohydrolase from Pseudomonas stutzeri expressed in Bacillus licheniformis; mixed β-glucanase, cellulase and xylanase from Rasamsonia emersonii; mixed β-glucanase and xylanase from Disporotrichum dimorphosporum; polyvinyl alcohol (PVA)- polyethylene glycol (PEG) graft copolymer) and two groups of contaminants (non-dioxin-like polychlorinated biphenyls and pyrrolizidine alkaloids). Specifications for the following food additives were revised or withdrawn: advantame; annatto extracts (solavnt extracted bixin, ad solvent-extracted norbixin); food additives containing aluminium and/or silicon (aluminium silicate; calcium aluminium silicate; calcium silicate; silicon dioxide, amorphous; sodium aluminium silicate); and glycerol ester of gum rosin. Annexed to the report are tables or text summarizing the toxicological and dietary exposure information and information on specifications as well as the Committees recommendations on the food additives and contaminants considered at this meeting. PMID:27514183

  20. Aluminium based composites strengthened with metallic amorphous phase or ceramic (Al2O3) particles

    International Nuclear Information System (INIS)

    Highlights: • Al-based composites with amorphous Al strengthening phase were obtained. • A better adhesion of metallic amorphous particles than of ceramic phase. • Avoiding crystallization of amorphous phase during a composite pressing process. • Properties similar for 10% metallic amorphous and ceramic strengthening phases. • Better amorphization in case of melt spinning than gas atomization of the Al alloy. - Abstract: Two methods were used to obtain amorphous aluminium alloy powder: gas atomization and melt spinning. The sprayed powder contained only a small amount of the amorphous phase and therefore bulk composites were prepared by hot pressing of aluminium powder with the 10% addition of ball milled melt spun ribbons of the Al84Ni6V5Zr5 alloy (numbers indicate at.%). The properties were compared with those of a composite containing a 10% addition of Al2O3 ceramic particles. Additionally, a composite based on 2618A Al alloy was prepared with the addition of the Al84Ni6V5Zr5 powder from the ribbons used as the strengthening phase. X-ray studies confirmed the presence of the amorphous phase with a small amount of aluminium solid solution in the melt spun ribbons. Differential Scanning Calorimetry (DSC) studies showed the start of the crystallization process of the amorphous ribbons at 437 °C. The composite samples were obtained in the process of uniaxial hot pressing in a vacuum at 380 °C, below the crystallization temperature of the amorphous phase. A uniform distribution of both metallic and ceramic strengthening phases was observed in the composites. The hardness of all the prepared composites was comparable and amounted to approximately 50 HV for those with the Al matrix and 120 HV for the ones with the 2618A alloy matrix. The composites showed a higher yield stress than the hot pressed aluminium or 2618A alloy. Scanning Electron Microscopy (SEM) studies after compression tests revealed that the propagation of cracks in the composites

  1. The study of aluminium fly-ash composite produced by powder metallurgy

    International Nuclear Information System (INIS)

    About several tons of coal combustion by products, including fly-ash, slag, and flue gas desulfurization are produced by coal power electric plant. Major quantity of the fly ash is being used as additives in cements. Fly ash is also used as filler in polymers. In this work, 5%, 10% and 15% fly ash have been dispersed in aluminium powder in order to improve their hardness and wear resistance. By using powder metallurgy technique the composite pellets are then produced. The pellets are sintered at temperature of 550 degree C for 1 hour. Selected properties like hardness, Young's modulus and wear resistance have been measured. (Author)

  2. The effect of nickel on alloy microstructure and electrochemical behaviour of AA1050 aluminium alloy in acid and alkaline solutions

    International Nuclear Information System (INIS)

    The study investigates the influence of nickel and magnesium additions to AA1050 aluminium alloy on the alloy electrochemical behaviour in sodium hydroxide and hydrochloric solutions under conditions relevant to industries that use alkaline etching as a standard surface treatment procedure and to the lithographic and electronic industries where surface convolution is assisted by pitting in hydrochloric acid. Scanning and transmission electron microscopes were used to characterize the intermetallic particles, and scanning Kelvin probe microscopy was utilised in monitoring the surface potential. Nickel is shown to be incorporated into second phase particles, which mostly consisted of Al3Fe and α-(AlFeSi) phases, resulting in enhanced cathodic activity on the aluminium surface. Consequently, the dissolution rates of the superpure aluminium, alloys without nickel addition and alloy with nickel addition are increased respectively in sodium hydroxide, and increased pitting is respectively promoted in hydrochloric acid. In contrast, the addition of magnesium to the alloy had negligible influence on the etching and pitting behaviour.

  3. Impact properties of aluminium - glass fiber reinforced plastics sandwich panels

    Directory of Open Access Journals (Sweden)

    Mathivanan Periasamy

    2012-06-01

    Full Text Available Aluminium - glass fiber reinforced plastics (GFRP sandwich panels are hybrid laminates consisting of GFRP bonded with thin aluminum sheets on either side. Such sandwich materials are increasingly used in airplane and automobile structures. Laminates with varying aluminium thickness fractions, fiber volume fractions and orientation in the layers of GFRP were fabricated by hand lay up method and evaluated for their impact performance by conducting drop weight tests under low velocity impacts. The impact energy required for initiating a crack in the outer aluminium layer as well as the energy required for perforation was recorded. The impact load-time history was also recorded to understand the failure behavior. The damage depth and the damage area were measured to evaluate the impact resistance. Optical photography and scanning electron micrographs were taken to visualize the crack and the damage zone. The bidirectional cross-ply hybrid laminate (CPHL has been found to exhibit better impact performance and damage resistance than the unidirectional hybrid laminate (UDHL. Increase in aluminium thickness fraction (Al tf and fiber volume fraction (Vf resulted in an increase in the impact energy required for cracking and perforation. On an overall basis, the sandwich panels exhibited better impact performance than the monolithic aluminium.

  4. Improving Efficiency of Aluminium Sacrificial Anode Using Cold Work Process

    Science.gov (United States)

    Asmara, Y. P.; Siregar, J. P.; Tezara, C.; Ann, Chang Tai

    2016-02-01

    Aluminium is one of the preferred materials to be used as sacrificial anode for carbon steel protection. The efficiency of these can be low due to the formation of oxide layer which passivate the anodes. Currently, to improve its efficiency, there are efforts using a new technique called surface modifications. The objective of this research is to study corrosion mechanism of aluminium sacrificial anode which has been processed by cold work. The cold works are applied by reducing the thickness of aluminium sacrificial anodes at 20% and 40% of thickness reduction. The cathodic protection experiments were performed by immersion of aluminium connected to carbon steel cylinder in 3% NaCl solutions. Visual inspections using SEM had been conducted during the experiments and corrosion rate data were taken in every week for 8 weeks of immersion time. Corrosion rate data were measured using weight loss and linear polarization technique (LPR). From the results, it is observed that cold worked aluminium sacrificial anode have a better corrosion performance. It shows higher corrosion rate and lower corrosion potential. The anodes also provided a long functional for sacrificial anode before it stop working. From SEM investigation, it is shown that cold works have changed the microstructure of anodes which is suspected in increasing corrosion rate and cause de-passivate of the surface anodes.

  5. Corrosion of aluminium metal in OPC- and CAC-based cement matrices

    Energy Technology Data Exchange (ETDEWEB)

    Kinoshita, Hajime, E-mail: h.kinoshita@sheffield.ac.uk [Department of Materials Science and Engineering, The University of Sheffield, Mappin Street, Sheffield, S1 3JD (United Kingdom); Swift, Paul; Utton, Claire [Department of Materials Science and Engineering, The University of Sheffield, Mappin Street, Sheffield, S1 3JD (United Kingdom); Carro-Mateo, Beatriz [The Public University of Navarra, C/Esquíroz, 30 trasera, Pamplona 31007 (Spain); Marchand, Geraldine [The National Institute of Applied Sciences (INSA) Lyon, 20 Avenue Albert Einstein 69621 Villeurbanne Cedex (France); Collier, Nick [National Nuclear Laboratory, Chadwick House, Birchwood Park, Warrington, WA3 6AE (United Kingdom); Milestone, Neil [Industrial Research Ltd., 69 Gracefield Road, Lower Hutt, 5040 (New Zealand)

    2013-08-15

    Corrosion of aluminium metal in ordinary Portland cement (OPC) based pastes produces hydrogen gas and expansive reaction products causing problems for the encapsulation of aluminium containing nuclear wastes. Although corrosion of aluminium in cements has been long known, the extent of aluminium corrosion in the cement matrices and effects of such reaction on the cement phases are not well established. The present study investigates the corrosion reaction of aluminium in OPC, OPC-blast furnace slag (BFS) and calcium aluminate cement (CAC) based systems. The total amount of aluminium able to corrode in an OPC and 4:1 BFS:OPC system was determined, and the correlation between the amount of calcium hydroxide in the system and the reaction of aluminium obtained. It was also shown that a CAC-based system could offer a potential matrix to incorporate aluminium metal with a further reduction of pH by introduction of phosphate, producing a calcium phosphate cement.

  6. The influence of organophosphonic acid and conducting polymer on the adhesion and protection of epoxy coating on aluminium alloy

    OpenAIRE

    Dalmoro, Viviane; Alemán Llansó, Carlos; Ferreira, Carlos Arthur; Dos Santos, J.H.Z.; Azambuja, Denise S.; Armelín Diggroc, Elaine Aparecida

    2015-01-01

    In the present study we compared the beneficial effect on the incorporation of modified silane nanocoating and conducting polymer additive to the adhesion and protection of aluminium surface with epoxy coating. Results proved that the protection imparted by the silane coating, suitably modified with phosphonic groups, showed an excellent adhesion to the metallic substrate as well as good adherence with the epoxy outer layer, which result in an improved corrosion resistance. The incorporation ...

  7. Loss of aluminium during the process of Ti-Al-V alloy smelting in a vacuum induction melting (VIM) furnace

    OpenAIRE

    Blacha, L.; G. Siwiec; B. Oleksiak

    2013-01-01

    In the present paper, results of the study on changes in basic Ti-6Al-4V alloy component contents during smelting in the vacuum induction melting (VIM) furnace are presented. The experiments were performed at 5 – 1 000 Pa and 1 973–2 023 K. Assuming that the observed loss of aluminium from the alloy during smelting is the effect of evaporation, an additional thermodynamic analysis was performed aimed at determining evaporation coefficients.

  8. Residual stress in 7449 aluminium alloy forgings

    International Nuclear Information System (INIS)

    The through thickness residual stress distributions within three 120 mm thick rectilinear forgings, made from the high strength aluminium alloy 7449 have been measured using both neutron diffraction and deep hole drilling. Neutron diffraction measurements were made on two instruments, one using a pulsed spallation neutron source, the other a steady state reactor source. Heat treatment of the forgings included a rapid quench into cold water and it was the residual stresses arising from this step that were initially measured. Neutron diffraction measurements indicated large magnitude (>250 MPa) tensile residual stresses in the centre of an as quenched forging, balanced by surface regions stressed in compression (<-200 MPa). Sufficient measurements were made to permit the description of the residual stress distribution using area maps. Two forgings were stress relieved by cold compression immediately after quenching. The degree of plastic strain was either 2.5% or 4%, and was applied by a single application of force in the short transverse direction. Cold compressed forgings were found to have far lower residual stress when compared to the as quenched condition. The amount of cold compression was found to cause an insignificant difference in the final residual stress distribution. The neutron diffraction results are compared to measurements made by deep hole drilling and a new incremental variation of the technique. The deep hole was drilled through the centre of the forgings in the short transverse direction. Multiple neutron diffraction measurements were also made on the extracted cores from the deep hole measurements to assess the variation of the unstrained lattice parameter through the thickness of the forgings.

  9. PEMBINAAN PENGERAJIN BOKOR ALUMINIUM DI DESA MENYALI

    Directory of Open Access Journals (Sweden)

    I NYOMAN GDE ANTARA, dkk.

    2014-04-01

    Full Text Available Alluminium bowl craft industrial center is located in Menyali village Sawan district Buleleng regency of Bali province. In this business development, they faced some problems such as increasingly expensive alluminium plate raw materials, decreasing selling product prices due to competition among craftsmen, difficulty in extending the marketing, lack of capital, lack of knowledge in business management, and lack of technical capacity and production innovation. Currently the organization has been formed aluminum bowl craftsmen groups, they are “Sumber Urip” and “Sumur Jaya”. This organization is still limited to tradisional associations such as a community organization, has not led to organize in a micro-enterprise or cooperation. Their organization management should not be arranged. Therefore, they need helps from the government and other institutions to build this bowl craftsmen in developing their businesses through a group of micro-enterprises or cooperations. Wishly, with formal business entity that would facilitate access to a variety of coaching and help governments andother institutions. From the SWOT analysis, it is found some problems and solutions that should be done. Alluminium bowl craftsmen groups, named “Sumber Urip” and “Sumur Jaya” is not in the form of business entity or cooperation yet, so that the results of coaching have agreed to form a cooperation. Venture capital assistance for the development and production are still needed and to be an absolute given, but a way to market more absolute yield is given, through participation in various events exhibition to introduce the product is expected to expandits market share up to overseas or exports. In the production process it has been introduced that is appropriate technology for instant a rolling tool to make a wiring groove on the outside of the bowl, so that it will simplify and speed up the process, especially by aged mothers.Keywords: aluminium bowl, Menyali

  10. Low Speed Laser Welding of Aluminium Alloys Using Single-Mode Fiber Lasers

    OpenAIRE

    Tu, Jay; Paleocrassas, Alexander

    2010-01-01

    In this chapter, topics related to extending fiber laser welding of aluminium in the low speed range were discussed. General topics, such as the properties of aluminium and welding defects, review of high speed laser welding of aluminium, and fiber laser characteristics and optical setups for safety, were first reviewed. Recent research results on the modelling and validation of laser welding of aluminium, experimental characterization of low speed welding processes, and the instability pheno...

  11. Influence of Alkali Treatment on the Surface Area of Aluminium Dross

    OpenAIRE

    Zauzi, N. S. Ahmad; M. Z. H. Zakaria; Baini, R.; Rahman, M. R.; N. Mohamed Sutan; Hamdan, S

    2016-01-01

    Aluminium dross is an industrial waste from aluminium refining industry and classified as toxic substances. However, the disposal of dross as a waste is a burden to aluminium manufacturer industries due to its negative effects to the ecosystem, surface, and ground water. Therefore the purpose of this study is to evaluate the influence of sodium hydroxide (NaOH) on the surface area and pore size of aluminium dross. There were 3 stages in the treatment activities, which were leaching, precipita...

  12. The determination of boron in high-purity aluminium metal by spark-source mass spectrometry

    International Nuclear Information System (INIS)

    A method is described for the determination of boron in high-purity aluminium metal. Both isotopic boron lines (10B+1 and 11B+1) are used for the analysis. As there are no low-abundance isotopic lines for aluminium, measurements were made direct without reference to aluminium as an internal standard. The boron concentration values of eight aluminium samples analysed by this method compared favourably with results obtained from other techniques

  13. Aluminium salen and salan catalysts for polymerisation of novel monomers and macrostructures

    OpenAIRE

    MacDonald, Jarret Preston

    2016-01-01

    Aluminium salen and aluminium salan complexes are excellent catalysts for the ring-opening polymerisation of lactide. This thesis studied their efficacy in the polymerisation of novel monomers and their ability to build new macrostructures. Aluminium salen and aluminium salan complexes were tested as catalysts for ring-opening polymerisation of common aliphatic monomers where controlled polymer synthesis has not yet been achieved with similar systems. Excellent control over ...

  14. The significance of water ionic strength on aluminium toxicity in brown trout (Salmo trutta L.)

    International Nuclear Information System (INIS)

    The toxicity of aluminium to fish is related to interactions between aluminium and the gill surface. We investigated the possible effect of water ionic strength on this interaction. The mortality of brown trout (Salmo trutta L.) exposed to three different degrees of Al polymerisation was compared in water with increased ionic strength (mean 7.31 x 10-4 M) after additions of the base cations Ca2+, Mg2+, Na+ or K+, and in water with no such addition (mean ionic strength 5.58 x 10-4 M). Only a very slight ameliorating effect of increased ionic strength was observed, while the degree of Al polymerisation was of major importance in fish mortality. In addition, it was observed that smaller fish survived the Al exposures for a longer time than larger fish. We hypothesise that this is because larger fish are more susceptible to hypoxia than smaller fish. - Ionic strength has a slight ameliorating effect on Al toxicity in brown trout

  15. Determination of ultratrace amounts of uranium and thorium in aluminium and aluminium alloys by electrothermal vaporization/ICP-MS

    International Nuclear Information System (INIS)

    A method has been developed for determining the 0.01 ng g-1 level of uranium and thorium in aluminium and aluminium alloys by electrothermal vaporization (ETV)/ICP-MS. This method was found to be significantly interfered with any matrices or other elements contained. An ion-exchange technique was therefore applied to separate uranium and thorium from aluminium and other elements. It was known that uranium are adsorbed on an anion-exchange resin and thorium are adsorbed on cation-exchange resin. However, aluminium and copper were eluted with 6 M hydrochloric acid. Dissolve the sample with hydrochloric acid containing copper which was added for analysis of pure aluminium, and oxidize with hydrogen peroxide. Concentration of hydrochloric acid in the solution was adjusted to 6 M, and then passed the solution through the mixed ion-exchange resin column. After the uranium and thorium were eluted with 1 M hydrofluoric acid-0.1 M hydrochloric acid, the solution was evaporated to dryness. It was then dissolved with 1 M hydrochloric acid. Uranium and thorium were analyzed by ETV/ICP-MS using tungsten and molybdenum boats, respectively, since the tungsten boat contained high-level thorium and the molybdenum boat contained uranium. The determination limit of uranium and thorium were 0.003 and 0.005 ng g-1, respectively. (author)

  16. Behaviour of painted aluminium in Ibero-American atmosphere

    International Nuclear Information System (INIS)

    Aluminium generally presents good corrosion resistance to the atmosphere. However, unprotected aluminium and aluminium alloys weather outdoors to an ugly grey colour, which deepens to black in industrial atmospheres, and undergo superficial pitting in marine atmospheres, etc. Finishing technologies are applied for their protection and decoration in a wide range of applications. These technologies basically consist of two protection processes: anodizing and painting: the latter going from conventional solvent base paints to modern water-born, high solids and powder coatings. This paper considers the weathering performance of three paint systems: alkyl, polyurethane and polyester, after more than three years of exposure in a wide spectra of Ibero-American atmospheric conditions. The information reported includes resistance to undercutting corrosion at the scribe, filiform corrosion, fungal attack and change in the physico-chemical properties of the paint surface (loss of gloss, colour changes, chalking, etc.). (Author) 9 refs

  17. Sensitivity analysis on ultimate strength of aluminium stiffened panels

    DEFF Research Database (Denmark)

    Rigo, P.; Sarghiuta, R.; Estefen, S.; Lehmann, E.; Otelea, S. C.; Pasqualino, I.; Simonsen, Bo Cerup; Wan, Z.; Yao, T.

    2003-01-01

    This paper presents the results of an extensive sensitivity analysis carried out by the Committee III.1 "Ultimate Strength" of ISSC?2003 in the framework of a benchmark on the ultimate strength of aluminium stiffened panels. Previously, different benchmarks were presented by ISSC committees on...... ultimate strength. The goal has typically been to give guidance to the designer on how to predict the ultimate strength and to indicate what level of accuracy would be expected. This time, the target of this benchmark is to present reliable finite element methods to study the behaviour of axial compressed...... stiffened aluminium panels (including extruded profiles). Main objectives are to compare codes/models and to perfom quantitative sensitivity analysis of the ultimate strength of a welded aluminium panel on various parameters (typically the heat-affected zone). Two phases were planned. In Phase A, alle...

  18. Aluminium toxicity in the rat liver and brain

    International Nuclear Information System (INIS)

    To investigate the etiology of Alzheimer's disease, we examined the brain and liver tissue uptake of aluminium 5-75 days after aluminium injection into healthy rats. Ten days after the last injection, Al was detected in the brain and the brain cell nuclei by particle-induced X-ray emission (PIXE) analysis. Al was also demonstrated in the liver and the liver cell nuclei by PIXE analysis and electron energy loss spectrometry (EELS). The morphological changes of the rat brain examined 75 days after the injection were similar to those which have been reportedly observed in the brain of patients with Alzheimer's disease. These results support the theory that Alzheimer's disease is caused by irreversible accumulation of aluminium in the brain, as well as the nuclei of brain cells. (orig.)

  19. Comparative performance of aluminium copper and iron solar stills

    International Nuclear Information System (INIS)

    Three different metal sheets have been used in the fabrication of three different single sloping solar stills of the same surface geometry. The metals were galvanized iron, aluminium and copper. This paper presents the performance of the different stills operating under the same environmental conditions. The observed distillate yields was greatest for copper, then aluminium and lastly, iron still. The differences in the yields is attributed to the differences in the thermal conductivities of the metals. The equivalent local costs for the fabrication of the copper, aluminium and iron stills are respectively $160, $95 and $60. Taking the long run costs into consideration, the copper still is preferred because of its availability, durability, weldability and relatively higher conductivity of 380Wm-1K-1 value. (author). 9 refs, 2 figs, 2 tabs

  20. Reflection of infrared radiation from thin aluminium layers

    CERN Document Server

    Calatroni, Sergio

    2001-01-01

    The thermal shielding of the LHC magnets cryostats will make use of Multi-Layer Insulation. This is a sandwich of several Mylar (polyester) foils 6 µm thick coated with a thin film of aluminium, having a thickness of some 30 nm. The thickness of the aluminium film must be kept at a minimum to minimise lateral thermal conduction. The outer layer of this sandwich stays at a temperature of 20 K or below, and receives IR radiation from surfaces at 77 K (wavelength of 37.6 µm at the peak of blackbody radiation), which should be reflected with the highest efficiency. The minimum thickness for the aluminium layer to avoid transmission of the radiation can be calculated by making use of the skin effect theory, taking into account the changes in electrical properties that are due to the extremely low thickness of the film.

  1. Food additives

    Science.gov (United States)

    ... this page: //medlineplus.gov/ency/article/002435.htm Food additives To use the sharing features on this page, please enable JavaScript. Food additives are substances that become part of a food ...

  2. Chapter 12. The initial aluminium as a raw material for goods

    International Nuclear Information System (INIS)

    The aluminium-raw product and methods of its refining including sedimentation, refining by inert gases and by fluxes was considered. The chemical composition of commodity aluminium was considered as well. The initial processing of aluminium-raw product was studied

  3. Bakable aluminium vacuum chamber and bellows with an aluminum flange and metal seal for ultrahigh vacuum

    International Nuclear Information System (INIS)

    A bakable (2000C) aluminium alloy vacuum chamber and bellows (6063-T6) with an aluminium alloy (2219-T87) flange and metal seal (Helicoflex-HN: aluminium O-ring) has been constructed. Such components may be used in the assemblies of the vacuum chambers in proton synchrotrons and electron storage rings

  4. Structural perturbation of diphtheria toxoid upon adsorption to aluminium hydroxide adjuvant

    NARCIS (Netherlands)

    Regnier, Marie; Metz, Bernard; Tilstra, Wichard; Hendriksen, Coenraad; Jiskoot, Wim; Norde, Willem; Kersten, Gideon

    2012-01-01

    Aluminium-containing adjuvants are often used to enhance the potency of vaccines. In the present work we studied whether adsorption of diphtheria toxoid to colloidal aluminium hydroxide induces conformational changes of the antigen. Diphtheria toxoid has a high affinity for the aluminium hydroxide p

  5. Characterisation of Ga-coated and Ga-brazed aluminium

    Energy Technology Data Exchange (ETDEWEB)

    Ferchaud, E. [Universite de Nantes, Polytech' Nantes, Laboratoire Genie des Materiaux et Procedes Associes, Rue Christian Pauc, 44306 Nantes Cedex 3 (France); Christien, F., E-mail: frederic.christien@univ-nantes.fr [Universite de Nantes, Polytech' Nantes, Laboratoire Genie des Materiaux et Procedes Associes, Rue Christian Pauc, 44306 Nantes Cedex 3 (France); Barnier, V. [Ecole Nationale Superieure des Mines, MPI, CNRS UMR5146, Centre SMS, 158 Cours Fauriel, 42023 Saint Etienne (France); Paillard, P. [Universite de Nantes, Polytech' Nantes, Laboratoire Genie des Materiaux et Procedes Associes, Rue Christian Pauc, 44306 Nantes Cedex 3 (France)

    2012-05-15

    This work is devoted to the brazing of aluminium using liquid gallium. Gallium was deposited on aluminium samples at {approx} 50 Degree-Sign C using a liquid gallium 'polishing' technique. Brazing was undertaken for 30 min at 500 Degree-Sign C in air. EDS (Energy Dispersive X-ray Spectroscopy) and AES (Auger Electron Spectroscopy) characterisation of Ga-coated samples has shown that the Ga surface layer thickness is of ten (or a few tens of) nanometres. Furthermore, aluminium oxide layer (Al{sub 2}O{sub 3}) was shown to be 'descaled' during Ga deposition, which ensures good conditions for further brazing. Cross-section examination of Ga-coated samples shows that liquid gallium penetrates into the aluminium grain boundaries during deposition. The thickness of the grain boundary gallium film was measured using an original EDS technique and is found to be of a few tens of nanometres. The depth of gallium grain boundary penetration is about 300 {mu}m at the deposition temperature. The fracture stress of the brazed joints was measured from tensile tests and was determined to be 33 MPa. Cross-section examination of brazed joints shows that gallium has fully dissolved into the bulk and that the joint is really autogenous. - Highlights: Black-Right-Pointing-Pointer Aluminium can be brazed using liquid gallium deposited by a 'polishing' technique. Black-Right-Pointing-Pointer The aluminium oxide layer is 'descaled' during liquid Ga 'polishing' deposition. Black-Right-Pointing-Pointer EDS can be used for determination of surface and grain boundary Ga film thickness. Black-Right-Pointing-Pointer The surface and grain boundary Ga film thickness is of a few tens of nm. Black-Right-Pointing-Pointer Surface and grain boundary gallium dissolves in the bulk during brazing.

  6. Aging of maraging steel welds during aluminium alloy die casting

    OpenAIRE

    Klobčar, Damjan; Pleterski, Matej; Taljat, Boštjan; Kosec, Ladislav; Tušek, Janez

    2015-01-01

    The aim of this study is to evaluate precipitation annealing of 18% Ni maraging steel repair welds during aluminium die casting and to predict the prolonged in-service tool life. The emphasis of this study is the influence ofpost-weld precipitation annealing heat treatment and aluminium die casting thermal cycling on metallurgical and mechanical properties. A series of specimens of 1.2344 tool steel is prepared to which 1.6356 maraging steel is GTA weld cladded. Analysis of weld microstructur...

  7. Zinc- and aluminium making processes using HTGR process heat

    International Nuclear Information System (INIS)

    The high temperature gas-cooled reactor (HTGR) has frequently been suggested as a source of process heat for steel-making; now it has been suggested that it could also be used in the zinc- and aluminium-making processes. For that purpose, several procedures are proposed whereby the key steps in the reduction of zinc oxyde are the use of a gas produced and heated by the HTGR process heat source. Also for the aluminium making process a series of new techniques in connection with the Toth and Grothe processes, coupled to a HTGR, are discussed. (orig.)

  8. The hydrolysis of aluminium, a mass spectrometric study

    OpenAIRE

    Sarpola, A.

    2007-01-01

    Abstract This thesis is focused on the hydrolysis of aluminium, the polymerisation of the hydrolysis products, and how these can be monitored by mass spectrometric methods. The main aim of this research is to figure out how the aqueous speciation of aluminium changes as a function of pH (3.2–10), concentration (1–100 mM), reaction time (1s–14d), and counter anion (Cl-, SO42-, HCOO-). The method used was electrospray mass spectrometry. The results showed more variable speciation than those ...

  9. Spectrofluorimetric determination of microquantities of aluminium in uranium

    International Nuclear Information System (INIS)

    A rapid and sensitive method for the separation and spectrofluorimetric determination of microamounts of aluminium in uranium compounds is described. In sodium carbonate solution at pH 9.5-10.0, the uranyl ion forms a very stable anionic complex with the carbonate ion. In these conditions, uranium is not extracted by a chloroform oxine solution, while alumium is isolated as the tris(oxinate)aluminium(III) form. The interferences are previously extracted with chloroform as diethylditiocarbomates in the same tris(oxinate)aluminum(III) pH extraction. The sensitivity is 0,005 μ Al/ml of organic phase and the relative standard deviation is 10%

  10. Power quality results in energy efficient aluminium smelter operation

    Energy Technology Data Exchange (ETDEWEB)

    Wiestner, Max

    2010-09-15

    New aluminium smelters consume up to 2400MW of electrical energy making the energy efficiency aspect most important. Power quality, optimised power conversion systems and well engineered power plant interfaces are essential for highest energy efficiency. An early optimisation of the power system design will reduce the capital investment cost for the power plant and smelter substation as well as results in most energy efficient aluminium production. This paper describes and intends to discuss the power quality improvement concepts and designs as well as energy cost reduction opportunities which a high power quality system can achieve.

  11. Separation of 35S-sulfate on neutral aluminium oxide

    International Nuclear Information System (INIS)

    The results of 35S-sulfate chromatography on neutral aluminium oxide (γ-Al2O3) are presented. Possibility of quantitative adsorption of 35S-sulfate on Al2O3 from acidic or neutral potassium chloride solutions of high concentration is shown. Dynamic adsorption capacity of neutral aluminium oxide with respect to sulfate from weakly acidic potassium chloride solution equals near 10 μmol/ml of adsorbent. Optimal parameters for chromatographic isolation of 35S-sulfate without carrier from irradiated KCl target are determined. (author)

  12. Lubricated sliding wear behaviour of aluminium alloy composites

    OpenAIRE

    J. C. Walker; Rainforth, W. M.; Jones, H.

    2005-01-01

    Interest in aluminium alloy (Al-alloy) composites as wear resistant materials continues to grow. However, the use of the popular Al-alloy-SiC composite can be limited by the abrasive nature of the SiC, leading to increased counterface wear rates. This study reports new Al-alloy composites that offer high wear resistance, to a level similar to Al-alloy-SiC. Aluminium alloy (2124, 5056) matrix composites reinforced by nominally 15 vol.% of Cr3Si, MoSi2, Ni3Al and SiC particles were prepared by ...

  13. Determination of cadmium in aluminium by atomic absorption spectrometry

    International Nuclear Information System (INIS)

    A direct method for the determination of cadmium in elemental aluminium is described. Metal samples are dissolved in diluted hydrochloric acid and cadmium is determined by atomic absorption spectrometry in an air-acetylene flame. Interference by non-specific absorption observed at the analytical wavelength incorrected for by means of a non-absorbing line emitted by the hollow-cathode lamp. Relatively large amounts of arsenic do not interfere. The minimun determinable concentration of cadmium for this procedure is 2-3 ppm, expressed on aluminium basis. (author)

  14. Electrochemical noise from corroding carbon steel and aluminium

    International Nuclear Information System (INIS)

    Electrochemical noise measurements were conducted on carbon steel and aluminium in sodium chloride solutions. Noise parameters like standard deviation of potential and current, noise resistance, pitting index, noise power were studied for the purpose of measuring corrosion rate. These parameters compared well with the corrosion rate. Pitting index was not very reliable. Current noise was more close to the corrosion rates. General corrosion gave rise to white noise type of power spectrum while flicker noise type of spectrum was obtained from pitting attack. Sodium nitrite is shown to inhibit the corrosion of carbon steel. Aluminium corrodes in the early period of exposure and passivates during long exposure

  15. Prevention of Dealloying in Manganese Aluminium Bronze Propeller: Part II

    Directory of Open Access Journals (Sweden)

    Napachat Tareelap

    2014-03-01

    Full Text Available Due to the failure of manganese aluminium bronze (MAB propeller caused by dealloying corrosion as described in Part I [1], this work aims to study the prevention of dealloying corrosion using aluminium and zinc sacrificial anodes. The results indicated that both of the sacrificial anodes could prevent the propeller from dealloying. Moreover, the dealloying in seawater was less than that found in brackish water. It was possible that hydroxide ions, from cathodic reaction, reacted with calcium in seawater to form calcium carbonate film protecting the propeller from corrosion.

  16. Monitoring of slurry fields solutions of aluminium production

    International Nuclear Information System (INIS)

    Results of annual monitoring of slurry fields solutions of aluminium industrial production of Tajik Aluminium Plant are considered in this work. It is found that in summer period the containing of sulfate, carbonate, hydro carbonate and fluoride salts in slurry fields solutions increase. This is due to intensive evaporation of solvent (water). In autumn-winter period due to air temperature decreasing the precipitation of above mentioned salts is observed. The results of chemical analysis of slurry fields solutions are presented in this work. The slurry fields solutions are analyzed by means of X-ray and thermal analysis. The flowsheet of purification of processed slurry fields solutions from sodium sulphate is proposed.

  17. Gas accumulation at grain boundaries during 800 MeV proton irradiation of aluminium and aluminium-alloys

    International Nuclear Information System (INIS)

    Samples of pure aluminium (99.9999%) and commercial Al-2.7%Mg (AlMg3) and Al-1.1%Mg-0.5%Si (Al6061) alloys were irradiated with 800 MeV protons at the Los Alamos Meson Physics Facility (LAMPF) at a temperature between 40-1000C to a maximum dose of 0.2 dpa. Transmission electron microscopy (TEM) showed a complete absence of voids or bubbles in the grain interiors of the aluminium and the aluminium-alloys. Bubbles were clearly visible by TEM at grain boundaries in pure Al and the AlMg3 alloy; but bubbles were not visible in the Al6061 alloy. The bubble density in the AlMg3 alloy was considerably higher than in pure Al. The amount of gas accumulation at grain boundaries was found to depend on gas generation rate, alloying and cold-work microstructure. (orig.)

  18. Accumulation of Aluminium and Physiological Status of Tree Foliage in the Vicinity of a Large Aluminium Smelter

    Directory of Open Access Journals (Sweden)

    E. D. Wannaz

    2012-01-01

    Full Text Available A pollution gradient was observed in tree foliage sampled in the vicinity of a large aluminium production facility in Patagonia (Argentina. Leaves of Eucalyptus rostrata, and Populus hybridus and different needle ages of Pinus spec. were collected and concentrations of aluminium (Al and sulphur (S as well as physiological parameters (chlorophyll and lipid oxidation products were analyzed. Al and S concentrations indicate a steep pollution gradient in the study showing a relationship with the physiological parameters in particular membrane lipid oxidation products. The present study confirms that aluminium smelting results in high Al and sulphur deposition in the study area, and therefore further studies should be carried out taking into account potentially adverse effects of these compounds on human and ecosystem health.

  19. Occupational exposure to beryllium in primary aluminium production.

    Science.gov (United States)

    Skaugset, Nils Petter; Ellingsen, Dag G; Dahl, Kari; Martinsen, Ivar; Jordbekken, Lars; Drabløs, Per Arne; Thomassen, Yngvar

    2012-02-01

    Alumina used in the production of primary aluminium contains Be which partly vaporises from the cryolite bath into the workroom atmosphere. Since Be may be toxic at lower exposure levels than previously thought, the personal exposure to Be among workers in 7 Norwegian primary smelters has been assessed. In total, 480 personal Respicon® virtual impactor full shift air samples have been collected during 2 sampling campaigns and analysed for water soluble Be, Al and Na using inductively coupled plasma optical emission spectrometry. In addition, water soluble F(-) has been measured by ion chromatography. The Be air concentrations in the inhalable, thoracic and respirable aerosol fractions have been calculated. The Be concentrations in the inhalable aerosol fraction vary between the different smelters. The highest GM concentration of Be in the inhalable fraction (122 ng m(-3), n = 30) was measured in the prebake pot room of a smelter using predominantly Jamaican alumina where also the highest individual air concentration of 270 ng m(-3) of Be was identified. The relative distribution of Be in the different aerosol fractions was fairly constant with the mean Be amount for the two sampling campaigns between 44-49% in the thoracic fraction expressed as % of the inhalable amount. Linear regression analysis shows a high correlation between water soluble Be, Al, F and Na describing an average measured chemical bulk composition of the water soluble thoracic fraction as Na(5.7)Al(3.1)F(18). Be is likely to be present as traces in this particulate matter by replacing Al atoms in the condensed fluorides and/or as a major element in a nanoparticle sized fluoride. Thus, the major amount of Be present in the work room atmosphere of Al smelter pot rooms will predominantly be present in combination with substantial amounts of water soluble Al, F and Na. PMID:21993554

  20. Aluminium Uptake and Accumulation in the Hyperaccumulator Camellia Oleifera Abel

    Institute of Scientific and Technical Information of China (English)

    ZENG Qi-Long; CHEN Rong-Fu; ZHAO Xue-Qiang; WANG Huo-Yan; SHEN Ren-Fang

    2011-01-01

    Oiltea camellia (Camellia oleifera Abel.), an aluminium (Al) hyperaccumulator, grows well on acid soils in tropical or subtropical areas. In this study, the growth of oiltea camellia in response to Al application and the characteristics of Al uptake and accumulation were investigated using laboratory and field experiments. The growth of oiltea camellia seedlings in the nutrient solution tended to be stimulated by addition of Al. Results of the field experiment showed that oiltea camellia accumulated 11000 mg kg-1 Al in leaves within 10 months, and the average rate of A1 accumulation in new leaves was about 1 100 mg kg-1 month-1; however, the monthly rate varied and was highest in spring and autumn. The results of the laboratory experiment on Al uptake by oiltea camellia seedlings in CaCl2 solutions with various forms of Al showed that large amounts of Al supplied as Al3+ and Al complexes Al-malate (1:1) and Al-F (1:1) were influxed into oiltea camellia roots, whereas Al supplied as Al-citrate (1:1), Al-F (1:6), Al-oxalate (1:3), and Al-oxalate (1:1) complexes exhibited low affinity to oiltea camellia roots. The kinetics of Als+ cumulative uptake in excised roots and intact plants showed a biphasic pattern, with an initial rapid phase followed by a slow phase. The Al cumulative uptake was unaffected by low temperature,which indicated that Al uptake in oiltea camellia was a passive process. The efficient influx of Al into the roots and the high transport rate in specific seasons were presumed to account for the plentiful Al accumulation in leaves of oiltea camellia.

  1. Influence of sulphur impurities on the interfacial tension between aluminium and cryolite alumina melts

    Energy Technology Data Exchange (ETDEWEB)

    Korenko, M. [Slovak Academy of Sciences, Bratislava (Slovakia). Dept. of Inorganic Chemistry

    2007-05-15

    The interfacial tension (IFT) between aluminium and cryolite melts containing different salt additions (AlF{sub 3}, NaF,Na{sub 2}SO{sub 4}) has been measured during electrolysis by the capillary depression method. The technique is based on the measurement of the capillary depression occurring when a capillary, which is moved vertically down through the molten salt layer, passes through the metal/salt interface. The depression is measured by simultaneous video recording of the immersion height of the alumina capillary. The interfacial tension is strongly dependent on the n(NaF)/n(AlF{sub 3}) ratio. The addition of Na{sub 2}SO{sub 4} decreases the IFT of the aluminium/electrolyte interface. We also found the different influence of the conditions of electrolysis on the IFT in systems with and without Na{sub 2}SO{sub 4}. In systems without Na{sub 2}SO{sub 4} the IFT decreases with increasing current density, and in systems with Na{sub 2}SO{sub 4} it increases. (orig.)

  2. Formation and Characterization of Ceramic Nanocomposite Crystalline Coatings on Aluminium by Anodization

    Institute of Scientific and Technical Information of China (English)

    M.Mubarak Ali; V.Raj

    2013-01-01

    Ceramic nanocomposite coatings have been synthesized on aluminium by using lithium sulphate electrolyte with zirconium silicate additive by anodization.The effects of current density (CD) on microhardness,structure,composition and surface topography of the oxide layer formed at various CDs (0.1-0.25 A/cm2) have been studied.Crystalline coatings formed at 0.25 A/cm2 have been (width 95 nm) observed with a relatively uniform distribution confirmed by scanning electron microscopy.Additionally,the average microhardness value of ceramic nanocomposite coatings fabricated from lithium sulphate-zirconium silicate bath is approximately 8.5 times higher than that of the as-received aluminium.The surface statistics of the coatings is discussed in detail to explain the roughness and related parameters for better understanding.These observations demonstrate the importance of surface statistics in controlling the morphology of the coatings and its properties.From the X-ray diffraction investigations,it can be concluded that the formed nanocomposite coatings are crystalline in nature and that the crystallinity of the coatings decreases with increasing applied current density.

  3. Sodium oleate adsorption and its effect on dissolution of aluminium, iron and their alloys in neutral media

    Energy Technology Data Exchange (ETDEWEB)

    Rozenfel' d, I.L.; Loskutov, A.I.; Kuznetsov, Yu.I.; Popova, L.I.; Oleinik, S.V.; Alekseev, V.N. (AN SSSR, Moscow. Inst. Fizicheskoj Khimii)

    Sodium oleate adsorption and its effect on the dissolution of aluminium, iron, aluminium-6% magnesium alloy and the Kh18N10T steel are studied in neutral media (buffer borate solutions, containing additions of SO/sub 4//sup 2 -/ or Cl/sup -/). In the region of protective concentrations of inhibitor the strictly oriented, densely compressed polylayers of sodium oleate are formed, in which the axes of carboxyl groups and fatty chains are directed in perpendicular to the metal surface. The bond strength of the adsorbed layers with a sublayer is conditioned by their polymerization, which is accompanied by the scission of double bonds in molecules. A relation between the protective ability, orientation and state of polymerization of the adsorbed layers is established. Sodium oleate adsorption on the oxidazed surface of metals does not result in the formation of new compounds, and iron oleate is formed on the reduced surface of iron.

  4. Sodium oleate adsorption and its effect on dissolution of aluminium, iron and their alloys in neutral media

    International Nuclear Information System (INIS)

    Sodium oleate adsorption and its effect on the dissolution of aluminium, iron, aluminium-6% magnesium alloy and the Kh18N10T steel are studied in neutral media (buffer borate solutions, containing additions of SO42- or Cl-). In the region of protective concentrations of inhibitor the strictly oriented, densely compressed polylayers of sodium oleate are formed, in which the axes of carboxyl groups and fatty chains are directed in perpendicular to the metal surface. The bond strength of the adsorbed layers with a sublayer is conditioned by their polymerization, which is accompanied by the scission of double bonds in molecules. A relation between the protective ability, orientation and state of polymerization of the adsorbed layers is established. Sodium oleate adsorption on the oxidazed surface of metals does not result in the formation of new compounds, and iron oleate is formed on the reduced surface of iron

  5. Role of acidic chemistries in steam treatment of aluminium alloys

    DEFF Research Database (Denmark)

    Din, Rameez Ud; Jellesen, Morten Stendahl; Ambat, Rajan

    2015-01-01

    The effect of acidic chemistry on the accelerated growth of oxide on aluminium alloys Peraluman 706TM and AA6060 under exposure to high temperature steam was investigated. Studied chemistries were based on citrates and phosphates. Results showed that the presence of citrate and phosphate anions...

  6. Aluminium dissolution for spray pulverization with nitric acid

    International Nuclear Information System (INIS)

    A comparative study of the nitric acid dissolution of aluminium, by immersion and spray pulverization has been carried out in laboratory scale. As a result, the optimum operation conditions to control reaction in the plant are fixed. Operation costs are also evaluated. (author)

  7. STRUCTURE OF ECAP ALUMINIUM AFTER DIFFERENT NUMBER OF PASSES

    Directory of Open Access Journals (Sweden)

    Lucia Ilucová

    2011-05-01

    Full Text Available The structure of high purity (99.99% aluminium processed by equal channel angular pressing in the as pressed state after different number of passes was examined using various stereological methods. An extreme inhomogeneity and complicated anisotropy was observed along the body of rod-like specimens.

  8. 1.3. Processing of aluminium production solid wastes

    International Nuclear Information System (INIS)

    The reprocessing of solid wastes of aluminium production, including fluorine regeneration, carbon regeneration, and extraction of valuable components was considered in this chapter. The main methods of fluorine regeneration, including alkaline, acidic, two-stage leaching, hydrochemical, burning, flotation, sintering, vacuum-thermal pyro hydrolysis were considered as well.

  9. Local electrochemical behaviour of 7xxx aluminium alloys

    NARCIS (Netherlands)

    Andreatta, F.

    2004-01-01

    Aluminium alloys of the 7xxx series (Al-Zn-Mg-Cu) are susceptible to localized types of corrosion like pitting, intergranular corrosion and exfoliation corrosion. This represents a limitation for the application of these alloys in the aerospace components because localized corrosion might have a neg

  10. Electrochemical Characterisation of Filiform Corrosion on Aluminium Rolled Products

    NARCIS (Netherlands)

    Huisert, M.

    2001-01-01

    When aluminium is protected by an organic coating a special form of corrosion can occur underneath the organic coating; filiform corrosion. This form of corrosion manifests itself as threadlike filaments under the coating, it causes local delamination of the coating and the coating cannot protect th

  11. Establishment of Integrated Information Displays in Aluminium Surfaces Using Nanomanufacturing

    DEFF Research Database (Denmark)

    Prichystal, Jan Phuklin; Bladt, Henrik Henriksen; Hansen, Hans Nørgaard

    2005-01-01

    Bang & Olufsen has been working with a method for manufacturing ultra-thin structures in Aluminium that can be penetrated by light. This has resulted in a patent describing how to obtain this effect by etching of local areas in a solid material. The idea behind an invisible display in Aluminum co...... ultra-short pulses, selective etching + anodizing, and electrochemical machining....

  12. On the Numerical Determination of Optimal Textures of Aluminium

    OpenAIRE

    Burgholzer, P; Scherzer, O.

    1994-01-01

    In this paper a mathematical algorithm is studied to improve the deep-drawing quality of an aluminium sheet. The deep-drawing quality is usually expressed in terms of the normal anisotropie. In our mathematical model we use Taylor theory and ideal orientations to reformulate this problem as a nonlinear optimization problem for the normal anisotropie. Some numerical examples are presented.

  13. Waste treatment of fission product solutions containing aluminium nitrate

    International Nuclear Information System (INIS)

    In the Rossendorf molybdenum-99 production facility AMOR short-term irradiated aluminium clad fuel elements from the Rossendorf Research Reactor are reprocessed. Following extractive recovery of the enriched uranium the facility system has to be disposed of the fission product-Al(NO3)3 solution. Investigations on waste conditioning of such solutions are presented. (author)

  14. Hydrogen generation from aluminium corrosion in reactor containment spray solutions

    International Nuclear Information System (INIS)

    The aluminium corrosion experiments in reactor containment spray solutions, under the conditions expected to prevail during LOCA in BWR and PWR, were performed in order to investigate relationships between temperature, pH and hydrogen production rates. In order to simulate the conditions in a BWR containment realistic ratios between aluminium surface and water volume and between aluminium surface and oxygen volume were used. Three different aluminium alloys were exposed to spray solutions: AA 1050, AA 5052 and AA 6082. The corrosion rates were measured for BWR solutions (deaerated and aerated) with pH 5 and 9 at 50, 100 and 1500C. The pressure was constantly 0.8 MPa. The hydrogen production rate was measured by means of gas chromatography. In deionized BWR water the corrosion rates did not exceed about 0.05 mm/year in all cases, i.e. were practically independent of temperature and pH. Hydrogen concentrations were less than 0.1 vol.% in cooled dry gas. Corrosion rates and hydrogen production in PWR alkaline solution measured at pH 9.7 and 1500C were very high. AA 5052 alloy was the best material

  15. Microstructure and defect chemistry of yttrium aluminium garnet ceramics

    International Nuclear Information System (INIS)

    This thesis describes basic aspects concerning the defect chemistry and the microstructure of yttrium aluminium garnet ceramics. The work consists of three parts: a literature study, an experimental part and a section giving computer simulation data of defects. (author). 320 refs.; 68 figs.; 72 schemes; 32 tabs

  16. Finite size melting of spherical solid-liquid aluminium interfaces

    DEFF Research Database (Denmark)

    Chang, J.; Johnson, Erik; Sakai, T.; Saka, H.

    2009-01-01

    We have investigated the melting of nano-sized cone shaped aluminium needles coated with amorphous carbon using transmission electron microscopy. The interface between solid and liquid aluminium was found to have spherical topology. For needles with fixed apex angle, the depressed melting tempera...... the conclusion that the depressed melting temperature is not controlled solely by the inverse radius 1/R. Instead, we found a direct relation between the depressed melting temperature and the ratio between the solid-liquid interface area and the molten volume.......We have investigated the melting of nano-sized cone shaped aluminium needles coated with amorphous carbon using transmission electron microscopy. The interface between solid and liquid aluminium was found to have spherical topology. For needles with fixed apex angle, the depressed melting...... temperature of this spherical interface, with radius R, was found to scale linearly with the inverse radius 1/R. However, by varying the apex angle of the needles we show that the proportionality constant between the depressed melting temperature and the inverse radius changes significantly. This led us to...

  17. SOLUBILITY OF SILICON IN CAST ALUMINIUM ALLOY AFTER ELECTROHYDROPULSE TREATMENT

    OpenAIRE

    Dyachenko, S.; Fedchenko, N.

    2006-01-01

    The structure of cast aluminium alloy AЛ9 exposed to electrohydropulse treatment (EHPT) was studied. It has been shown that after EHPT solubility of silicon in alloy matrix was increased. With the help of thermodynemic analysis the structural changes in metal after EHPT were explained.

  18. Effect of Low Strain Rate on Formability of Aluminium Alloy

    OpenAIRE

    Bidulská, J.; T. Kvačkaj; Bidulský, R.; Cabbibo, M.; Evangelista, E.

    2007-01-01

    Effect of low strain rate on formability of aluminium alloy 2014 by means of torsion test was performed. The presented experimental results exhibit decrease of the ductility with increase and decrease of ε and T, respectively, and optimal values of , ε T are thus obtained.

  19. Aluminium enriched diffusion layers on NiAl alloy

    Czech Academy of Sciences Publication Activity Database

    Bartuška, Pavel; Lašek, Jiří; Paidar, Václav

    2003-01-01

    Roč. 19, č. 3 (2003), s. 185-188. ISSN 0267-0844 R&D Projects: GA AV ČR IAA1041302 Institutional research plan: CEZ:AV0Z1010914 Keywords : intermetallics based on Ni-Al * aluminium enriched diffusion layers * local elemental analysis Subject RIV: BM - Solid Matter Physics ; Magnetism Impact factor: 0.571, year: 2003

  20. Anisotropy of tertiary creep in aluminium-based composites

    Czech Academy of Sciences Publication Activity Database

    Dobeš, Ferdinand; Milička, Karel

    Naples : University of Naples, 2005 - (Crivelli-Visconti, I.), s. 225-226 [Advancing with composites 2005. Naples (IT), 11.10.2005-14.10.2005] Institutional research plan: CEZ:AV0Z20410507 Keywords : metal matrix composite * tertiary creep * aluminium alloys Subject RIV: JI - Composite Materials

  1. Aluminium in food and daily dietary intake estimate in Greece.

    Science.gov (United States)

    Bratakos, Sotirios M; Lazou, Andriana E; Bratakos, Michael S; Lazos, Evangelos S

    2012-01-01

    Aluminium content of foods, as well as dietary aluminium intake of the Greek adult population, was determined using graphite furnace atomic absorption spectroscopy after microwave sample digestion and food consumption data. Al content ranged from 0.02 to 741.2 mg kg⁻¹, with spices, high-spice foods, cereal products, vegetables and pulses found to be high in Al. Differences in aluminium content were found between different food classes from Greece and those from some other countries. Aluminium intake of Greeks is 3.7 mg/day based on DAFNE Food Availability Databank, which uses data from the Household Budget Surveys. On the other hand, according to the per capita food consumption data collected by both national and international organisations, Al intake is 6.4 mg day⁻¹. Greek adult population has an Al intake lower than the Provisional Tolerable Weekly Intake of 7 mg kg⁻¹ body weight established by EFSA. Cereals and vegetables are the main Al contributors, providing 72.4% of daily intake. PMID:24779693

  2. Examples on cold forged aluminium components in automotive industry

    DEFF Research Database (Denmark)

    Bay, Niels; Kolsgaard, A.

    2000-01-01

    The present paper describes the possibilites of applying cold forging for manufacturing of light weight components in aluminium. A short description of the basic cold forming processes forms the basis for describing the great variety in design of cold forged components. Examples are mainly taken ...... from automotive industry but in a few cases also from other industrial sectors to show the possibilities....

  3. Hydrogen evolution from aluminium in reactor containment spray solutions

    International Nuclear Information System (INIS)

    Three different aluminium alloys were exposed to conditions similar to BWR and PWR containment spray waters at 50, 100 and 1500C. BWR deionized water gives corrosion rates of at most 0.05 mm/year and hydrogen concentrations less than 0.1-1%. On the contrary PWR alkaline solutions give very high corrosion rates and hydrogen contents. (Auth.)

  4. Persistent Skin Reactions and Aluminium Hypersensitivity Induced by Childhood Vaccines

    DEFF Research Database (Denmark)

    Salik, Elaha; Løvik, Ida; Andersen, Klaus E; Bygum, Anette

    2016-01-01

    There is increasing awareness of reactions to vaccination that include persistent skin reactions. We present here a retrospective investigation of long-lasting skin reactions and aluminium hypersensitivity in children, based on medical records and questionnaires sent to the parents. In the 10-year...

  5. Effects of Aluminium in Forest. Results of a pilot experiment

    Energy Technology Data Exchange (ETDEWEB)

    Mulder, J.; Wit, H. de; Nygaard, P.H.

    1996-01-01

    This conference paper deals with an Norwegian pilot project which started in 1995 and finishing early 1999, investigates the solubility and phyto-toxicity of aluminium (Al) in mature forest ecosystems. The project consists of three major parts, including field manipulation study of Norwegian spruce stands, laboratory experiments and modelling Al chemistry in the root zone. 15 refs.

  6. Application of artificial neural networks for modelling correlations in age hardenable aluminium alloys

    Directory of Open Access Journals (Sweden)

    F. Musharavati

    2010-07-01

    Full Text Available Purpose: This paper discusses some of the preliminary results of an ongoing research on the applications of artificial neural networks (ANNs in modelling, predicting and simulating correlations between mechanical properties of age hardenable aluminium alloys as a function of alloy composition.Design/methodology/approach: Appropriate combinations of inputs and outputs were selected for neural network modelling. Multilayer feedforward networks were created and trained using datasets from public literature. Influences of alloying elements, alloy composition and processing parameters on mechanical properties of aluminium alloys were predicted and simulated using ANNs models.Two sample t-tests were used to analyze the prediction accuracy of the trained ANNs.Findings: Good performances of the neural network models were achieved. The models were able to predict mechanical properties within acceptable margins of error and were able to provide relevant simulated data for correlating alloy composition and processing parameters with mechanical properties. Therefore, ANNs models are convenient and powerful tools that can provide useful information which can be used to identify desired properties in new aluminium alloys for practical applications in new and/or improved aluminium products.Research limitations/implications: Few public data bases are available for modelling properties. Minor contradictions on the experimental values of properties and alloy compositions were also observed. Future work will include further development of simulated data into property charts.Practical implications: Correlations between mechanical properties and alloy compositions can help in identifying a suitable alloy for a new or improved aluminum product application. In addition, availability of simulated structure-process-property data or charts assists in reducing the time and costs of trial and error experimental approaches by providing near-optimal values that can be used

  7. Mechanically milled aluminium matrix composites reinforced with halloysite nanotubes

    Directory of Open Access Journals (Sweden)

    L.A. Dobrzański

    2012-12-01

    Full Text Available Purpose: The present work describes fabrication of aluminium AlMg1SiCu matrix composite materials reinforced with halloysite nanotubes by powder metallurgy techniques and hot extrusion.Design/methodology/approach: Mechanical milling, compacting and hot extrusion successively are considering as a method for manufacturing metal composite powders with a controlled fine microstructure and enhanced mechanical properties. It is possible by the repeated welding and fracturing of powders particles mixture in a highly energetic ball mill.Findings: The milling process has a huge influence on the properties of powder materials, changing the spherical morphology of as-received powder during milling process to flattened one due to particle deformation followed by welding and fracturing particles of deformed and hardened enough which allows to receive equiaxial particles morphology again. The investigation shows that so called brittle mineral particles yields to plastic deformation as good as ductile aluminium alloy particles. That indicates that the halloysite powder can play a role of the accelerator during mechanical milling. High energy ball milling as a method of mechanical milling improves the distribution of the halloysite reinforcing particles throughout the aluminium matrix, simultaneously reducing the size of particles. The apparent density changes versus milling time can be used to control the composite powders production by mechanical milling and the presence of halloysite reinforcements particles accelerates the mechanical milling process.Research limitations/implications: Contributes to knowledge about technology, structure and properties of aluminium alloy matrix composite material reinforced with mineral nanoparticles.Practical implications: Conducted research shows that applied technology allows obtaining very good microstructural characteristics.Originality/value: It has been confirmed that halloysite nanotubes can be applied as an effective

  8. Canada: a big investment for the aluminium valorization; Canada: un gros investissement pour la valorisation de l'aluminium

    Energy Technology Data Exchange (ETDEWEB)

    Anon.

    2005-02-01

    An amount of more than 2.4 millions of dollars has been given by the Quebec at the research and development sector for the aluminium valorization. Six plans will be studied by more than 30 searchers and 20 students in technology. (O.M.)

  9. Corrosion of aluminium in copper-aluminium couples under a marine environment: Influence of polyaniline deposited onto copper

    Energy Technology Data Exchange (ETDEWEB)

    Vera, Rosa, E-mail: rvera@ucv.c [Instituto de Quimica, Facultad de Ciencias, Pontificia Universidad Catolica de Valparaiso, Avda. Brasil 2950, Casilla 4059, Valparaiso (Chile); Verdugo, Patricia [Departamento de Quimica y Bioquimica, Facultad de Ciencias, Universidad de Valparaiso, Av. Gran Bretana 1111, Valparaiso (Chile); Orellana, Marco; Munoz, Eduardo [Instituto de Quimica, Facultad de Ciencias, Pontificia Universidad Catolica de Valparaiso, Avda. Brasil 2950, Casilla 4059, Valparaiso (Chile)

    2010-11-15

    Research highlights: {yields} The presence of Polyaniline in the Al-Cu system produces a decrease in the oxygen reduction reaction. {yields} In the marine enviroment, aluminium in Al-Cu couples, suffers pitting and exfoliation. {yields} The aluminium deterioration increases with chloride and enviromental sulphur dioxide presence, mainly when it is united to bare copper. - Abstract: In this study, we examined how aluminium corrosion in Al-Cu/PANI galvanic couples in a marine environment is influenced by deposition of polyaniline (PANI) on copper. Polarization curves and immersion assays in 0.1 M NaCl were performed. The morphologies of etched Al and corrosion products were observed by SEM, and the Al ions in solution were quantified by atomic absorption spectroscopy. A reduction in aluminium damage due to galvanic corrosion was observed as a result of decreased effective area for the oxygen reduction reaction on Cu/PANI electrode. Furthermore, an electrochemical reduction of PANI from leucoemeraldine to emeraldine base is proposed.

  10. Design of the lines of aluminium drawing. Part 1; Conception des filieres de filage d'aluminium. Partie 1

    Energy Technology Data Exchange (ETDEWEB)

    Cescutti, J.P.; Ravaille, N. [Pechiney, Div. Filiage, 75 - Paris (France)

    2005-12-15

    After a general presentation, the second paragraph gives the main reasons of the complexity of the problem to be solved. Coming from the 'sciences of design', these aspects give valuable data to structure the analysis of the progress ways in the field of the design of the lines of aluminium extrusion. (O.M.)

  11. Decreased toxicity of aluminium when the ionic strength increases in water; Blir aluminium mindre toksisk naar ionestyrken i vannet oeker?

    Energy Technology Data Exchange (ETDEWEB)

    Alstad, E.W. [Oslo Univ. (Norway)

    1996-01-01

    The conference paper evaluates the acute mortality of fish caused by the toxicity of aluminium in water. The evaluation is based on the polymerization hypothesis. According to the author, the level of toxicity decreases when the concentration and charge of ions increase. The paper presents the preliminary results from the executed experiment. 2 refs., 2 figs., 1 tab.

  12. Energy conversion from aluminium and phosphate rich solution via ZnO activation of aluminium

    International Nuclear Information System (INIS)

    Electrochemical power sources have motivated intense research efforts in the development of alternative ‘green’ power sources for ultra-low powered bioelectronic devices. Biofuel cells employ immobilized enzymes to convert the available chemical energy of organic fuels directly into electricity. However, biofuel cells are limited by short lifetime due to enzyme inactivation and frequent need to incorporate mediators to shuttle electrons to the final electron acceptor. In this context, other electrochemical power sources are necessary in energy conversion and storage device applications. Here we report on the fabrication and characterization of a membrane-free aluminium/phosphate cell based on the activation of aluminium (Al) using ZnO nanocrystal in an Al/phosphate cell as a ‘green’ alternative to the traditional enzymatic biofuel cells. The hybrid cell operates in neutral phosphate buffer solution and physiological saline buffer. The ZnO modifier in the phosphate rich electrolyte activated the pitting of Al resulting in the production of hydrogen, as the reducing agent for the reduction of H2PO4− ions to HPO32− ions at a formal potential of −0.250 V vs. Ag/AgCl. Specifically, the fabricated cell operating in phosphate buffer and physiological saline buffer exhibit an open-circuit voltage of 0.810 V and 0.751 V and delivered a maximum power density of 0.225 mW cm−2 and 1.77 mW cm−2, respectively. Our results demonstrate the feasibility of generating electricity by activating Al as anodic material in a hybrid cell supplied with phosphate rich electrolyte. Our approach simplifies the construction and operation of the electrochemical power source as a novel “green” alternative to the current anodic substrates used in enzymatic biofuel cells for low power bioelectronics applications. - Graphical abstract: Display Omitted - Highlights: • ZnO activation of metallic Al for generating electricity for bioelectronic applications. • Selective

  13. Energy conversion from aluminium and phosphate rich solution via ZnO activation of aluminium

    Energy Technology Data Exchange (ETDEWEB)

    Slaughter, Gymama, E-mail: gslaught@umbc.edu; Sunday, Joshua; Stevens, Brian

    2015-08-01

    Electrochemical power sources have motivated intense research efforts in the development of alternative ‘green’ power sources for ultra-low powered bioelectronic devices. Biofuel cells employ immobilized enzymes to convert the available chemical energy of organic fuels directly into electricity. However, biofuel cells are limited by short lifetime due to enzyme inactivation and frequent need to incorporate mediators to shuttle electrons to the final electron acceptor. In this context, other electrochemical power sources are necessary in energy conversion and storage device applications. Here we report on the fabrication and characterization of a membrane-free aluminium/phosphate cell based on the activation of aluminium (Al) using ZnO nanocrystal in an Al/phosphate cell as a ‘green’ alternative to the traditional enzymatic biofuel cells. The hybrid cell operates in neutral phosphate buffer solution and physiological saline buffer. The ZnO modifier in the phosphate rich electrolyte activated the pitting of Al resulting in the production of hydrogen, as the reducing agent for the reduction of H{sub 2}PO{sub 4}{sup −} ions to HPO{sub 3}{sup 2−} ions at a formal potential of −0.250 V vs. Ag/AgCl. Specifically, the fabricated cell operating in phosphate buffer and physiological saline buffer exhibit an open-circuit voltage of 0.810 V and 0.751 V and delivered a maximum power density of 0.225 mW cm{sup −2} and 1.77 mW cm{sup −2}, respectively. Our results demonstrate the feasibility of generating electricity by activating Al as anodic material in a hybrid cell supplied with phosphate rich electrolyte. Our approach simplifies the construction and operation of the electrochemical power source as a novel “green” alternative to the current anodic substrates used in enzymatic biofuel cells for low power bioelectronics applications. - Graphical abstract: Display Omitted - Highlights: • ZnO activation of metallic Al for generating electricity for

  14. Additivity dominance

    Directory of Open Access Journals (Sweden)

    Paul Rozin

    2009-10-01

    Full Text Available Judgments of naturalness of foods tend to be more influenced by the process history of a food, rather than its actual constituents. Two types of processing of a ``natural'' food are to add something or to remove something. We report in this study, based on a large random sample of individuals from six countries (France, Germany, Italy, Switzerland, UK and USA that additives are considered defining features of what makes a food not natural, whereas ``subtractives'' are almost never mentioned. In support of this, skim milk (with major subtraction of fat is rated as more natural than whole milk with a small amount of natural vitamin D added. It is also noted that ``additives'' is a common word, with a synonym reported by a native speaker in 17 of 18 languages, whereas ``subtractive'' is lexicalized in only 1 of the 18 languages. We consider reasons for additivity dominance, relating it to omission bias, feature positive bias, and notions of purity.

  15. Investigation of effect of some factors on boron coprecipitaion from magnesium chloride brines by aluminium hydroxide

    International Nuclear Information System (INIS)

    The conditions of precipitation of boron with aluminium hydroxide from natural magnesium chloride solutions of different concentration and from artificial solutions of boric acid with the same content of magnesium chloride were investigated. The effect of acidity on precipitation of boron with aluminium hydroxide was investigated over the pH range from 4.5 to 8.0. The dependence of the degree of boron extraction on pH has two maxima and one minimum. For concentrated mother liquors the maximum is at pH=5.0, and for dilute ones, at pH=6.5. The nature of the metal hydroxide and of the anions present in the solutions affects the shift of the maximum and minimum of boron extraction. It has been established that with an increase in temperature from 15 deg C to 45 deg C boron precipitation from weakly acid solutions decreases as a result of destruction of the boron polyanions with the formation of orthoboric acid. In a weakly alkaline medium, however, boron extraction increases due to additional release of magnesium hydroxide

  16. Effect Of Severe Plastic Deformation On Microstructure Evolution Of Pure Aluminium

    Directory of Open Access Journals (Sweden)

    Leszczyńska-Madej B.

    2015-06-01

    Full Text Available Processes of severe plastic deformation (SPD are defined as a group of metalworking techniques in which a very large plastic strain is imposed on a bulk material in order to make an ultra-fine grained metal. The present study attempts to apply Equal-Channel Angular Pressing (ECAP, Hydrostatic Extrusion (HE and combination of ECAP and HE to 99.5% pure aluminium. ECAP process was realized at room temperature for 16 passes through route Bc using a die having an angle of 90°. Hydrostatic extrusion process was performed with cumulative strain of 2.68 to attain finally wire diameter of d = 3 mm. The microstructure of the samples was investigated by means of transmission and scanning electron microscopy. Additionally, the microhardness was measured and statistical analysis of the grains and subgrains was performed. Based on Kikuchi diffraction patterns misorientation was determined. The measured grain/subgrain size show, that regardless the mode of deformation process (ECAP, HE or combination of ECAP and HE processes, grain size is maintained at a similar level – equal to d = 0.55-0.59 μm. A combination of ECAP and HE has achieved better properties than either single process and show to be a promising procedure for manufacturing bulk UFG aluminium.

  17. Nuclear analysis of a rare earth containing protective oxide on aluminium

    Energy Technology Data Exchange (ETDEWEB)

    Gorman, J.D.; Paterson, P.J.K. [Royal Melbourne Inst. of Tech., VIC (Australia); Hughes, A.E. [Commonwealth Scientific and Industrial Research Organisation (CSIRO), Melbourne, VIC (Australia). Div. of Materials Science

    1996-12-31

    The aim is study was to examine the thickness of the conversion coating as well as the elemental depth distribution of cerium and molybdenum using Rutherford Backscattering Spectroscopy (RBS), Scanning Electron Microscopy (SEM), Scanning Auger Electron Spectroscopy and Forward Recoil Spectroscopy (FRS). In addition, RBS has been used to examine how changes in processing conditions, particularly the treatment temperatures, influences the coating thickness and Ce distribution at each process step. SEM established that a crazed oxide structure was developed over the matrix of the alloy using the above process steps. RBS was chosen to provide elemental concentration versus depth information on these samples since it is largely insensitive to surface topography when the detector is set to high scattering angles. A other advantage of using RBS for this particular system is that the heavy elements incorporated into the coating such as Ce and Mo because of their high atomic number compared to the aluminium oxide, are well separated from aluminium and oxygen at their higher recoil energies. Forward Recoil Spectroscopy is capable of detecting hydrogen and it has been used to confirm that the coating is hydrated and to establish the hydrogen distribution within the final oxide coating on each alloy. 7 refs., 1 tab., 4 figs.

  18. A Tapered Aluminium Microelectrode Array for Improvement of Dielectrophoresis-Based Particle Manipulation

    Directory of Open Access Journals (Sweden)

    Muhamad Ramdzan Buyong

    2015-05-01

    Full Text Available In this work, the dielectrophoretic force (FDEP response of Aluminium Microelectrode Arrays with tapered profile is investigated through experimental measurements and numerical simulations. A standard CMOS processing technique with a step for the formation of a tapered profile resist is implemented in the fabrication of Tapered Aluminium Microelectrode Arrays (TAMA. The FDEP is investigated through analysis of the Clausius-Mossotti factor (CMF and cross-over frequency (fxo. The performance of TAMA with various side wall angles is compared to that of microelectrodes with a straight cut sidewall profile over a wide range of frequencies through FEM numerical simulations. Additionally, electric field measurement (EFM is performed through scanning probe microscopy (SPM in order to obtain the region of force focus in both platforms. Results showed that the tapered profile microelectrodes with angles between 60° and 70° produce the highest electric field gradient on the particles. Also, the region of the strongest electric field in TAMA is located at the bottom and top edge of microelectrode while the strongest electric field in microelectrodes with straight cut profile is found at the top corner of the microelectrode. The latter property of microelectrodes improves the probability of capturing/repelling the particles at the microelectrode’s side wall.

  19. Mechanical and Abrasive Wear Properties of Anodic Oxide Layers Formed on Aluminium

    Institute of Scientific and Technical Information of China (English)

    W.Bensalah; K.Elleuch; M.Feki; M.Wery; H.F.Ayedi

    2009-01-01

    Aluminium oxide coatings were formed on aluminium substrates in oxalic acid-sulphuric acid bath. Abrasion tests of the obtained anodic layers were carried out on a pin-on-disc machine in accordance with the ISO/DP 825 specifications. The Vickers microhardness, D (HV0.2). and the abrasion weight loss, Wa (mg) were measured. Influence of oxalic acid concentration (Cox), bath temperature (T) and anodic current density (J) on D and Wa has been examined, and the sulphuric acid concentration (Caul) was maintained at 160 g.L-1. It was found that high microhardness and abrasive wear resistance of oxide layers were produced under low temperatures and high current densities with the addition of oxalic acid. The morphology and the composition of the anodic oxide layer were examined by scanning electron microscopy (SEM), atomic force microscopy (AFM), optical microscopy and glow-discharge optical emission spectroscopy (GDOES). It was found that the chemistry of the anodizing electrolyte, temperature, and current density are the controlling factors of the mechanical properties of the anodic oxide layer.

  20. Deep surface rolling for fatigue life enhancement of laser clad aircraft aluminium alloy

    International Nuclear Information System (INIS)

    Highlights: • Deep surface rolling as a post-repair enhancement technology was applied to the laser cladded 7075-T651 aluminium alloy specimens that simulated corrosion damage blend-out repair. • The residual stresses induced by the deep surface rolling process were measured. • The deep surface rolling process can introduce deep and high magnitude compressive residual stresses beyond the laser clad and substrate interface. • Spectrum fatigue test showed the fatigue life was significantly increased by deep surface rolling. - Abstract: Deep surface rolling can introduce deep compressive residual stresses into the surface of aircraft metallic structure to extend its fatigue life. To develop cost-effective aircraft structural repair technologies such as laser cladding, deep surface rolling was considered as an advanced post-repair surface enhancement technology. In this study, aluminium alloy 7075-T651 specimens with a blend-out region were first repaired using laser cladding technology. The surface of the laser cladding region was then treated by deep surface rolling. Fatigue testing was subsequently conducted for the laser clad, deep surface rolled and post-heat treated laser clad specimens. It was found that deep surface rolling can significantly improve the fatigue life in comparison with the laser clad baseline repair. In addition, three dimensional residual stresses were measured using neutron diffraction techniques. The results demonstrate that beneficial compressive residual stresses induced by deep surface rolling can reach considerable depths (more than 1.0 mm) below the laser clad surface

  1. Role of exogenous and endogenous silicon in ameliorating behavioural responses to aluminium in a freshwater snail

    International Nuclear Information System (INIS)

    Aluminium accumulation by the freshwater snail Lymnaea stagnalis is correlated with behavioural depression which is ameliorated by addition of orthosilicic acid. We hypothesised that Si is relocated to the digestive gland in response to Al, leading to the formation of non-toxic hydroxyaluminosilicates (HAS). Exposure to 500 μg l-1 Al for 30 days was associated with an initial period of behavioural depression, followed by apparent tolerance and subsequent depression, suggesting saturation of the cellular detoxification pathway during prolonged exposure. Exogenous Si (7.77 mg l-1) completely ameliorated all behavioural effects of Al but did not prevent its accumulation. In the presence of added Al, significantly more of this Si was accumulated by the tissues, compared to controls and snails exposed to Si alone. In snails exposed to Al plus Si, Al and Si concentrations were significantly correlated, with a ratio around 3:1 Al:Si, consistent with the presence of the non-toxic HAS protoimogolite. - Capsule: Toxicity of aluminium to freshwater snails is ameliorated by orthosilicic acid

  2. 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.

  3. Steel sheet composite materials with foamed aluminium; Stahlblechverbundwerkstoffe mit geschaeumtem Aluminium

    Energy Technology Data Exchange (ETDEWEB)

    Baumeister, J.; Weber, M. [Institut fuer Angewandte Materialforschung, Bremen (Germany); Bleck, W.; Hagen, H. von [Technische Hochschule Aachen (Germany). Lehrstuhl und Inst. fuer Eisenhuettenkunde

    1999-07-01

    Sandwich structured steel sheets with a core of foamed aluminium can be produced by roll-bonding and glueing. Results of corrosion tests and laser welding tests so far were positive. Several applications have been proposed but none of them has been implemented as yet. The material is recommended for applications with a profile of requirements comprising structurally and functionally relevant characteristics. Recycling is unproblematic. [German] Zur Herstellung von Stahlblechsandwichverbunden mit einem Aluminiumschaumkern lassen sich die Verfahren Walzplattieren und Kleben einsetzen. Es sind Sandwichverbunde mit Gesamtdichten von 0,7 bis 2,0 g/cm{sup 3} und Gesamtdicken zwischen 10 und 32 mm darstellbar. Die Tafelgroessen fuer die vielversprechendsten Verfahren liegen derzeit bei ueber DIN A3 (konventionell geschaeumt) oder 160 mm x mehrere m (kontinuierlich im Banddurchlaufofen geschaeumt) und 2 m x 600 mm (geklebt). Es lassen sich gute mechanische Eigenschaften des Sandwichverbundes (Biegesteifigkeit) und hohe Versagensreserven bei Druck- und Biegebeanspruchungen sowie interessante funktionelle Eigenschaften (z.B. hohe Energieaufnahme) erzielen. Aus Tastversuchen zu Korrosionseigenschaften und Fuegeverfahren (Laserschweissen) konnten positive Resultate gewonnen werden. Vorschlaege zu Anwendungen bestehen, aber ein direkter Einsatz ist noch nicht realisiert worden. Ein Einsatz des Werkstoffverbundes ist sinnvoll in Gebieten, in denen ein Anforderungsprofil von strukturell und funktionell relevanten Eigenschaften vorherrscht. Das Recycling der rein metallischen Verbunde ist problemlos. (orig.)

  4. Numerical and experimental investigations of aluminium powder compaction; Numerische und experimentelle Untersuchungen zum Pulverpressen von Aluminium

    Energy Technology Data Exchange (ETDEWEB)

    Hanini, K.; Doege, E.; Schmidt-Juergensen, R. [Institut fuer Umformtechnik und Umformmaschinen, (IFUM) Universitaet Hannover, Welfengarten 1A, 30167 Hannover (Germany)

    2003-08-01

    The FEM simulation is a powerful means which can drastically reduce the time to production and costs in the optimization of powder forming processes. The current paper investigates experimentally and numerically die compaction of aluminium powder. The plastic deformation is formulated by using the Drucker-Prager-Cap-model. This yield criterion describes the compressibility of porous bodies and allows the prediction of crack formation in the green compact. Axial compaction tests have been performed to determine material parameters for hardening. Simulation examples are presented to demonstrate the ability of the model to compute the distribution of the relative density. Furthermore, the compaction of an axisymmetric workpiece was simulated in order to determine optimal tools kinematics and to avoid crack formation. (Abstract Copyright [2003], Wiley Periodicals, Inc.) [German] Die Auslegung und Optimierung pulvertechnologischer Umformverfahren basiert bisher zu einem grossen Teil auf Erfahrungswissen. Die numerische Simulation bietet hierbei eine kosten- und zeitsparende Alternative. Besonders hat sich die Finite-Elemente-Methode (FEM) als leistungsfaehiges Simulationsverfahren bewaehrt. Im Rahmen dieser Arbeit wird das Pulverpressen von Aluminiumpulver numerisch und experimentell untersucht. Hierbei wird das Drucker-Prager-Cap-Modell verwendet, um das kompressible Verhalten des Pulvers abzubilden und moegliche Rissbildungen waehrend des Pressvorgangs vorherzusagen. Durch Pressversuche werden die Materialkennwerte fuer dieses Modell hinsichtlich der Verdichtung und Verfestigung des Aluminiumpulvers ermittelt. Der Pressvorgang wird anhand ausgewaehlter Referenzbauteile simuliert. Von besonderem Interesse ist hierbei die Berechnung der Verteilung der relativen Dichte und die Vermeidung der Rissbildung durch Optimierung der Stempelkinematik. (Abstract Copyright [2003], Wiley Periodicals, Inc.)

  5. Effects of Nano-Aluminium on The Combustion of A PolyNIMMO-Based Propellant

    Institute of Scientific and Technical Information of China (English)

    Clive Woodley; Peter Henning

    2014-01-01

    Propellants containing micro-aluminium particles have been shown to produce faster burn rates than conventional gun propellants.However,they are also more abrasive than conventional propellants.Nano-material propellants have been reported to give similar benefits to micron-material propellants but without the disadvantage of increased abrasion.Tests were conducted to compare the burn rates,ignitability and wear rates of a propellant loaded with 0% aluminium,15% micro-aluminium and 15%nano-aluminium.Closed vessel tests showed a burn rate increase of 39% in the range 30-250 MPa,and 70% at low pressure (50-100 MPa)for the nano-aluminium propellant compared with the baseline propellant.The micro-aluminium propellant showed only a 10% increase in the burn rate compared with the standard propellant.The ignition delay for the nano-aluminium propellant was slightly shorter than that of the baseline propellant.Substantially increased wear rates were measured for the micro-aluminium propellant.The nano-aluminium propellant showed reduced wear rates compared with the micro-aluminium propellant but these were still substantially greater than those for the baseline propellant.

  6. Effect of Ti, Nb, Cr and B on Structure and Mechanical Properties of High Aluminium Cast Iron

    OpenAIRE

    D. Kopyciński

    2013-01-01

    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 r...

  7. Additivity dominance

    OpenAIRE

    Paul Rozin; Claude Fischler; Christy Shields-Argeles

    2009-01-01

    Judgments of naturalness of foods tend to be more influenced by the process history of a food, rather than its actual constituents. Two types of processing of a ``natural'' food are to add something or to remove something. We report in this study, based on a large random sample of individuals from six countries (France, Germany, Italy, Switzerland, UK and USA) that additives are considered defining features of what makes a food not natural, whereas ``subtractives'' are almost never mentioned....

  8. Active metal brazing of different metals to aluminium nitride ceramics

    International Nuclear Information System (INIS)

    During recent years aluminium nitride ceramics for substrates, coolers and components have found more applications in micro- and power electronics. Aluminium nitride ceramic with high thermal conductivity, small CTE and good thermal shock resistance is used in aeronautical equipment as well as in drive systems of undergrounds and high speed trains. Different metals and alloys can be bonded to AIN by the so-called 'AMB-process'. The bonding mechanism is based on the use of so-called active metals like Ti, Zr, Hf. Copper conductor lines can be brazed onto AIN-substrates and components, resistor sheets can be applied on ceramic water coolers and a couple of other metals and alloys like tantalium, titanium, KOVAR and steel can be attached to AIN-ceramics by active brazing. Processing, analytical aspects and some special applications will be discussed. (author)

  9. Effect of pressurized steam on AA1050 aluminium

    DEFF Research Database (Denmark)

    Jariyaboon, Manthana; Møller, Per; Ambat, Rajan

    2012-01-01

    measurements were used to study corrosion behavior. Findings - A 590?nm boehmite oxide layer was generated on AA1050 associated with partially dissolved and/or fallen off Fe-containing intermetallic particles after exposure to pressurized steam. A significant reduction (25 times) in anodic and cathodic......Purpose - The purpose of this paper is to understand the effect of pressurized steam on surface changes, structures of intermetallic particles and corrosion behavior of AA1050 aluminium. Design/methodology/approach - Industrially pure aluminium (AA1050, 99.5 per cent) surfaces were exposed to...... pressurized steam produced from a commercial pressure cooker at the maximum temperature of 116oC for 10?min. Surface morphology was observed using SEM-EDX and FIB-SEM. Phase identification and compositional depth profiling were investigated using XRD and GDOES, respectively. Potentiodynamic polarization...

  10. Production of aluminium oxide from the kaolin waste reprocessing

    International Nuclear Information System (INIS)

    The kaolin processing for paper covering produces a great volume of residues formed primary by clay mineral kaolinite which was in this study, the starting point for the synthesis of ammonium alum aiming to obtain free sodium alumina with fine grade for ceramic manufacture. The synthesis process to obtain ammonium alum consisted of the following procedures: residues calcination and sulphuric leaching of meta kaolinite followed by neutralization/ crystallization of aluminium sulphate solution with ammonium hydroxide concentrated solution. The effect of calcination temperature (650 deg C, 700 deg C and 750 deg C), calcination time of residues (30 min, 60 min and 120 min),sulphuric acid concentration as well as leaching temperature (70 deg C, 80 deg C and 90 deg C) on kinetics of aluminium leaching were studied. The influence of pH on ammonium alum crystallization was also studied. Data on chemical analysis, XRD and DTA of raw material utilized and synthesized are presented and discussed. (author)

  11. The nature of point defects in plastically deformed aluminium

    International Nuclear Information System (INIS)

    In order to find out which types of point defect are produced by plastic deformation, 57Co-doped aluminium specimens were cold worked at various temperatures by unidirectional tensile deformation or cyclic torsion. The specimens were then annealed at increasing temperatures, and the trapping of defects at the 57Co probes was studied by Moessbauer spectroscopy. In none of the experiments were interstitials found, although it is known that in aluminium 57Co probes readily trap interstitials after low-temperature particle irradiation. However, vacancy trapping was found in two temperature ranges corresponding to two different migration energies of vacancies: in dislocations Esub(m)sup(d) approx.0.2 to 0.3 eV and in the lattice Esub(m) approx.= 0.6 eV. The consequences of the results on models of point defect production by cold working are discussed. (author)

  12. Impact of Inert Metal Particles Flow on Aluminium Plate

    Institute of Scientific and Technical Information of China (English)

    WANG Zhongqi; LIU Yi; CHEN Yahong; BAI Chunhua

    2008-01-01

    Inert metal explosive, a new kind of explosive, is a mixture of high explosive and inert metal particle.When this kind of explosive is detonated, an inert metal particle flow will be formed by the explosive product driving.To determine the characteristics of the movement of the metal particle flow, a series of aluminium plates were designed to be the targets on which the metal particle flow impacted.The test result was presented and a numerical model was set up to analyze the impact of the high speed inert metal particles on aluminium plate.Based on the numerical analysis, the relationship between the characteristic of the mark on the target plate and the initial condition of the inert metal particles was proposed.From the analysis of the impact on target plates, more information about the movement of the metal particles could be reconstructed.

  13. Mechanisms of de cohesion in cutting aluminium matrix composites

    International Nuclear Information System (INIS)

    In this paper properties and applications of aluminium matrix composites are presented with a composite reinforced with saffil fibres selected for topical study. Behavior of matrix and reinforcement during machining with a cutting tool is analyzed. The paper presents an explosive quick-stop device designed to obtain undisturbed machined surface for examination. Meso hardness measurements of deformed structure, resultant chips and built-up-edge were carried out. Scanning micrographs of machined surface are presented with morphology and types of chips analysed. Values of the fibrousness angle ψ and thickening index kh of chip are evaluated. The research performed has enabled the authors to define mechanisms of e cohesion during cutting aluminium matrix composites. The results received for composite material are compared with those pertinent to aluminum alloys.

  14. Effects and mechanisms of grain refinement in aluminium alloys

    Indian Academy of Sciences (India)

    K T Kashyap; T Chandrashekar

    2001-08-01

    Grain refinement plays a crucial role in improving characteristics and properties of cast and wrought aluminium alloys. Generally Al–Ti and Al–Ti–B master alloys are added to the aluminium alloys to grain refine the solidified product. The mechanism of grain refinement is of considerable controversy in the scientific literature. The nucleant effects i.e. which particle and its characteristics nucleate -Al, has been the subject of intensive research. Lately the solute effect i.e. the effect of dissolved titanium on grain refinement, has come into forefront of grain refinement research. The present paper attempts to review the literature on the nucleant effects and solute effects on grain refinement and addresses the importance of dissolved titanium in promoting nucleation of -Al on nucleant particles.

  15. Sorption of strontium-90 on anodized aluminium (2)

    International Nuclear Information System (INIS)

    Adsorption of the 90Sr+90Y system on anodized aluminium as a function of oxide layer thickness, purity of aluminum and temperature has been studied. It was found that only the adsorption of Sr2+ ions is affected by the oxide layer thickness. The content of admixtures in aluminium was meaningless from the point of view of adsorption capacity. An increase of Sr2+ adsorption with temperature was observed in the range from 20 to 600C. From the investigation of desorption it follows that the irreversibility of adsorption is higher for yttrium than for strontium and that the oxide layers of greater porosity tie up more strongly both kinds of ions. (author)

  16. Structural colours and applications to anodised aluminium surfaces

    DEFF Research Database (Denmark)

    Johansen, Villads Egede

    solve the problem. The problem is investigated by first reviewing existing work within colouration and visual appearance. This includes a study on how colours are perceived by humans and an investigation of the characteristics with which a surface appearance is properly described. Subsequently......, nanostructures and surface profiles are investigated using optimisation and topology optimisation in order to understand the limitations and design freedom of colour engineering. This is then followed by a study of the effect of disorder on a nanoscale level in order to tailor surface reflections for a smooth......, pleasing appearance. Afterwards, optical models for scattering of non-deterministic geometries suitable for anodised aluminium are considered. The outcome of the investigations are several different proposals for obtaining a white appearance for aluminium. These are described in the thesis alongside a...

  17. Microstructure evolution and grain refinement in asymmetrically rolled aluminium

    International Nuclear Information System (INIS)

    Aluminium alloy sheets were asymmetrically rolled and annealed. Asymmetric rolling was applied by imposing different velocity ratios between the top and bottom rolls, from 1 to 1.5. After cold rolling, the microstructures of various samples were analysed by electron back scatter diffraction, whereas the mechanical properties were characterized by stress–strain curves and microhardness measurements. The asymmetrical rolling process was examined as an alternative method to obtain fine- or even ultrafine-grained aluminium. The main purpose of this paper is to describe, qualitatively and quantitatively, the influence of asymmetrical rolling on microstructure evolution. Grain size, misorientation, image quality factor and other parameters were characterized and analysed in some detail. In the present study, a unique approach has been used for the first time to examine the possibility of applying the asymmetric rolling process in the preparation of materials with controlled heterogeneity

  18. TORSIONAL DEFORMATION AND FATIGUE BEHAVIOUR OF 6061 ALUMINIUM ALLOY

    Directory of Open Access Journals (Sweden)

    marini marno

    2012-02-01

    Full Text Available Torsional deformation and fatigue behaviour of both solid and thin-walled tubular specimens were made from as-received and heat treated 6061 aluminium alloy were studied. 6061 aluminium alloy have been widely used as a candidate material in automobile, aerospace, aircraft and structural application because of their superior mechanical properties such as high strength to weight ratio, good ductility and others. The differences in cyclic deformation and fatigue behaviours between round and solid specimens where a stress gradient exist, and thin-walled tubular specimens where a uniform stress state is commonly assumed, are also discussed. Von Mises and Tresca criteria has been used to predict the monotonic and cyclic deformation curve and compared to the torsional data obtained from the experiment. The S-N curve was used to present and evaluate the fatigue life of the specimens. Through fractographic analysis, failure criteria of fracture surfaces were observed and discussed. 

  19. Experimental evidence for a dynamical crossover in liquid aluminium.

    Science.gov (United States)

    Demmel, F; Fraile, A; Szubrin, D; Pilgrim, W-C; Morkel, C

    2015-11-18

    The temperature dependence of the dynamic structure factor at next-neighbour distances has been investigated for liquid aluminium. This correlation function is a sensitive parameter for changes in the local environment and its Fourier transform was measured in a coherent inelastic neutron scattering experiment. The zero frequency amplitude decreases in a nonlinear way and indicates a change in dynamics around 1.4 ∙ Tmelting. From that amplitude a generalized viscosity can be derived which is a measure of local stress correlations on next-neighbour distances. The derived generalized longitudinal viscosity shows a changing slope at the same temperature range. At this temperature the freezing out of degrees of freedom for structural relaxation upon cooling sets in which can be understood as a precursor towards the solid state. That crossover in dynamics of liquid aluminium shows the same signatures as previously observed in liquid rubidium and lead, indicating an universal character. PMID:26465204

  20. Environment pollution with aluminium around a coalburning electric power plant

    International Nuclear Information System (INIS)

    The experiments were carried out from November 1991 till November 1993 on the area surrounding an electric power plant within the circle of 20 km diameter and five geographical directions (N, S, SE, E, W). The results presented in this paper have indicated the threats caused by emissions of the power plant ashes and dusts. Mean aluminium content in soil has been multiply surpassed on the area studied. This must have as impact on fauna and flora. The distribution and intensity of pollution is determined first of all by the distance from the emitters and direction of prevailing winds. A part of aluminium contained in water soluble compounds can be distributed on large areas, what adds a lot to the threat to animals. That is why high chimneys do not solve the problem of pollution around big industrial plants. (author)

  1. Tailored Aluminium based Coatings for Optical Appearance and Corrosion Resistance

    DEFF Research Database (Denmark)

    Aggerbeck, Martin

    The current project investigated the possibility of designing aluminium based coatings focusing on the effect of composition and surface finish on the optical appearance and on the alkaline corrosion properties using titanium as the main alloying element. The main results and discussions of this...... the previously described magnetron sputtered Al-Ti coatings showed that 13 wt. % titanium and more improved the corrosion resistance at pH 13.5 and this was further improved by heat treatment, especially at 400 °C and more. The improved corrosion properties were ascribed to structural relaxation......, decreased galvanic potential differences in the microstructure, and protection from the network of the Al3Ti phases precipitated during the heat treatment. Laser surface cladding of aluminium containing up to 20 wt. % Ti6Al4V were studied focusing on the microstructure and the alkaline corrosion properties...

  2. Radiative capture of polarized neutrons by aluminium and manganese nuclei

    International Nuclear Information System (INIS)

    The angular distribution of the intensity is calculated for primary and secondary gamma-rays emitted after polarized neutron capture in a polarized target. Also the circular polarization is derived for capture of polarized neutrons by unoriented nuclei. Interference between the reaction channels and all possible dipole/quadrupole mixing is taken into account. Some aspects of p-wave and s-p interference are discussed. The results of these calculations are applied to the experiments on aluminium and manganese. In the nuclear orientation experiment with aluminium a 'brute force' polarized target was used. For five levels in 28Al the spin value could be determined uniquely. No evidence for significant M2/E1 mixing is found. A ferromagnetic MnSb sample was used to polarize the manganese nuclei. Unique spin values are assigned to 13 states in 56Mn. The magnetic hyperfine field on the Mn nuclei is determined to be negative

  3. Melting defect characterization in aluminium alloys by using computerized tomography

    International Nuclear Information System (INIS)

    This paper analyses the performance of parallel beam X-ray transmission computerized tomography, in the characterization of melting defects on a aluminium alloy. The results obtained presented a spatial resolution approximately of 0.8 mm. The porosity distribution existent in the piece appears as noise at the tomographic images with impossible detection. From the tomograms analyses it was possible to classify two defect regions at the pieces: empty and large pore concentration

  4. Studies on the chelation of aluminium for biological application

    International Nuclear Information System (INIS)

    Potentiometric determinations of the strength of chelation of aluminium(III) by citrate and 3-carboxy-1,5-pentanedioic acid have been made at 37,0 plus minus 0,1 degree Celsius and I = 150 mmol dm-3 NaCl. From these results, the citrate complex is inferred to be tridentate with coordination through the two terminal carboxyl groups and the central hydroxyl group. This structure is confirmed by 13C nuclear magnetic resonance

  5. Characteristics of particulate emissions from aluminium electrolysis cells

    OpenAIRE

    Gaertner, Heiko

    2013-01-01

    Modern sampling and analysis techniques were applied to study the morphology and composition of pot exhaust particles from aluminium smelters. In this study the total spectrum of pot exhaust particles from prebake electrolysis cells was sampled on filters and in a standard cyclone. Application of a cascade impactor allowed for fractionation of raw gas dust into 12 fractions with particle diameters in the range from approximately 7 nm to 10 μm. The performed experiments demonstrated that the p...

  6. Experimental study of friction in aluminium bolted joints

    OpenAIRE

    Vincenzi N.; De Agostinis M.; Croccolo D.

    2010-01-01

    This study aims at developing an experimental tool useful to define accurately the friction coefficients in bolted joints and, therefore, at relating precisely the tightening torque to the bolt preloading force in some special components used in front motorbike suspensions. The components under investigation are some clamped joints made of aluminium alloy. The preloading force is achieved by applying a torque wrench to the bolt head. Some specific specimens have been appropriately desig...

  7. ICT measuring method of small gap in aluminium component

    International Nuclear Information System (INIS)

    Because of the limitation of image reconstruction theory, the spatial resolution and random dispersion of CT value determine the minimum measuring size of Industrial Computed Tomography (ICT). This paper put forward the local boundary integration conception and found a new method to precisely measure the gap between 0.01-0.15 mm in aluminium component. When the credibility is 95%, the measuring accuracy is better than ± 0.005 mm. (authors)

  8. Load carrying capacity analysis of materials for aluminium rims

    OpenAIRE

    Fajdiga, Matija; Čižman, Jure

    2015-01-01

    In this contribution we present an experimental simulation of the fatique strength of clamped aluminium rims. This is supported by numerical modelling using the Finite Element Method (FEM), which was used for stress-strain analysis of a model representing a clamped detail during bendings. The design and analysis of the model are made simultaneously on an integrated computer controlled test rig for testing the fatique strength of clamped parts subjected to bending. The simulation is evaluated ...

  9. Fatigue Strength of Friction Stir Welded Joints in Aluminium

    OpenAIRE

    Ericsson, Mats

    2005-01-01

    Solid state Friction stir welding (FSW) is of major interest in the welding of aluminium since it improves the joint properties. Many applications where Al-alloys are used are subject to varying load conditions, making fatigue failure a critical issue. In the scope of this thesis, the fatigue performance of friction stir welded AlMgSi-alloy 6082 has been investigated. Static and dynamic properties of different joint configurations and welds produced with varying process parameters have been d...

  10. Fabrication and characterisation of uranium, molybdenum, chromium, niobium and aluminium

    International Nuclear Information System (INIS)

    This paper describes fabrication of binary uranium alloys by melting and casting. The following alloys with nominal composition were obtained by melting in the vacuum furnace: uranium with niobium contents from 0.5%- 4.0% and uranium with molybdenum contents from 0.4% - 1.2%. Uranium alloys with chromium content from 0.4% - 1.2% and uranium alloy with 0.12% of aluminium were obtained by vacuum induction furnace (electric arc melting)

  11. Establishment of integrated information displays in aluminium surfaces using nanomanufacturing

    DEFF Research Database (Denmark)

    Prichystal, Jan; Hansen, Hans Nørgaard; Bladt, Henrik H.;

    2006-01-01

    Bang & Olufsen has been working with a method for manufacturing ultra-thin structures in aluminium that can be penetrated by light. This work has resulted in a patent describing how to obtain this effect by material removal in local areas in a solid material. The idea behind an invisible display ...... micromachining with ultra-short pulses, selective etching combined with anodizing, and electrochemical machining....

  12. Experimental study of aluminium honeycomb behaviour under dynamic multiaxial loading

    OpenAIRE

    Markiewicz E.; Haugou G.; Chaari F.; Zouari B.; Tounsi R.; Dammak F.

    2012-01-01

    Split Hopkinson Pressure Bar system (SHPB) with large-diameter and Nylon bars introducing a shear-compression loading device is used in order to investigate the dynamic behaviour of aluminium honeycomb under multiaxial loadings conditions. All shear-compression configurations including the loading angle variation from 0∘ to 60∘ are performed with an impact velocity of about 15m/s. The adapted SHPB system with the device are validated numerically and a phenomenon of separation between the inpu...

  13. TEM microstructure investigations of aluminium alloys used as coating substrate

    Directory of Open Access Journals (Sweden)

    T. Tański

    2013-01-01

    Full Text Available Purpose: The aim of this paper was investigated structure and properties of gradient coatings produced in PVD process on AlSi9Cu aluminium alloys.Design/methodology/approach: The following results concern the structures of the substrates and coatings with the application of electron transmission and scanning microscopy; phase composition of the coatings using X-ray diffraction and grazing incident X-ray diffraction technique (GIXRD; microhardness and wear resistance.Findings: The deposited coatings are characterized by a single, double, or multi-layer structure according to the applied layers system, and the individual layers are coated even and tightly adhere to the substrate as well to each other. The analysis of coatings obtained on the surface of cast aluminium alloys by the PVD processes show a clear - over 100% - increase of the microhardness, compared to the base material microhardness.Practical implications: Achieving of new operational and functional characteristics and properties of commonly used materials, including the Al-Si-Cu alloys is often obtained by heat treatment, ie, precipitation hardening and/or surface treatment due to application or manufacturing of machined surface layer coatings of materials in a given group of materials used for different surface engineering processes.Originality/value: The paper presents the research involving the PVD coatings obtained on an unconventional substrate such as aluminium alloys. Contemporary materials should possess high mechanical properties, physical and chemical, as well as technological ones, to ensure long and reliable use. The above mentioned requirements and expectations regarding the contemporary materials are met by the non-ferrous metals alloys used nowadays, including the aluminium alloys.

  14. Work Hardening and Mechanical Anisotropy of Aluminium Sheets and Profiles

    OpenAIRE

    Ryen, Øyvind

    2003-01-01

    The processing of aluminium alloys from casting to end product is associated with a large number of metallurgical phenomena. In order to further improve and optimise process routes and alloys, a thorough understanding of the thermomechanical treatments by experimental observations and physically based modelling is necessary.In part A of this thesis the work hardening behaviour of non-heat treatable alloys is followed up to large strains. The evolution in strength, microstructure and texture d...

  15. Numerical modeling of aluminium foam on two scales

    Czech Academy of Sciences Publication Activity Database

    Němeček, J.; Denk, F.; Zlámal, Petr

    2015-01-01

    Roč. 267, September (2015), s. 506-516. ISSN 0096-3003 R&D Projects: GA ČR(CZ) GAP105/12/0824 Institutional support: RVO:68378297 Keywords : closed-cell aluminium foam * Alporas * multiscale modeling * homogenization * FFT * finite element modeling Subject RIV: JI - Composite Materials Impact factor: 1.551, year: 2014 http://www.sciencedirect.com/science/article/pii/S0096300315001162

  16. Aluminium extrusion investigated by theory, experiment and FEM-analysis

    OpenAIRE

    Khorasani, Sepinood Torabzadeh

    2015-01-01

    The process of aluminium extrusion has important influence in metal forming industry because of its ability to produce profiles with different shapes, sizes and complicated geometries. The required extrusion load is depending on the process parameters such as the flow stress of the billet material, velocity field, strain rate distribution, and thermal conditions within extrusion. These conditions are so important for industries, and interesting for academia, that research has been...

  17. Texture development during recrystallization of aluminium containing large particles

    DEFF Research Database (Denmark)

    Juul Jensen, Dorte; Hansen, Niels; Humphreys, F. J.

    1985-01-01

    The recrystallization process in heavily deformed commercially pure aluminium containing large intermetallic particles was studied by in situ neutron diffraction texture measurements and various microscopical techniques including texture measurements in local areas and simultaneous determination of...... size and orientation of individual grains. The formation and growth of recrystallization nuclei at the particles and in the matrix were examined by correlating the measured change in texture to the observed change in microstructure. It was found that prolific nucleation of grains having a wide spread...

  18. Structural use of aluminium in the construction industry

    Energy Technology Data Exchange (ETDEWEB)

    Nethercot, D.A. [Imperial Coll., London (United Kingdom)

    2002-07-01

    Examples are given of the structural use of aluminium in the Civil Engineering and Building Industries. These are taken from various periods within the past 50 years. The contrast between relatively widespread use for quite major structures in the 50' and 60's with the niche markets of today is striking. Paradoxically, availability of technical guidance, linked to professionally prepared educational material, has never been better. (orig.)

  19. Oxidation of solid aluminium-magnesium alloy doped by scandium

    International Nuclear Information System (INIS)

    The oxidation of solid aluminium-magnesium alloy with scandium was studied by means of thermogravimetry method. The kinetic and energy parameters of oxidation process were defined. The kinetics of oxidation was studied by means of thermogravimetry method. The apparent activation energy was defined as well. The products of oxidation were studied by means of X-ray analysis method. It was shown that the main products of oxidation were γ-Al2O3 and Mg O.

  20. Study of twist boundaries in aluminium. Structure and intergranular diffusion

    International Nuclear Information System (INIS)

    This research thesis addresses the study of grain boundaries in oriented crystals, and more particularly the systematic calculation of intergranular structures and energies of twist boundaries of <001> axis in aluminium, the determination of intergranular diffusion coefficients of zinc in a set of twist bi-crystals of same axis encompassing a whole range of disorientations, and the search for a correlation between these experimental results and calculated structures

  1. Wrought Aluminium Alloy Corrosion Propensity in Domestic Food Cooking Environment

    OpenAIRE

    Adeosun, S. O.; E. I. Akpan; S. A. Balogun

    2012-01-01

    The study on corrosion behaviour of wrought aluminium alloy in domestic food cooking conditions has been examined using the gravimetric approach. Flat cold rolled and annealed sheets were subjected to solutions of Capsicum annuum, L. esculentum, Allium cepa, and their blend under three conditions, namely, heating and cooling in still air, heating and cooling in refrigerator, and leaving some in open still atmosphere. Results show that corrosion occurred within the test period (288 hours) in t...

  2. Outstanding inhibitive effect of colchicine on aluminium alloy 6061 corrosion

    OpenAIRE

    Mudigere Krishnegowda Pavithra; Thimmappa Venkatarangaiah Venkateha; Mudigere Krishnegowda Punith Kumar; Nanjanagudu Subba Rao Anantha

    2015-01-01

    The corrosion protection ability of colchicine (CC) on Aluminium alloy 6061 (AA6061) in 3.5% NaCl medium was examined by potentiodynamic polarization, electrochemical impedance, and chronoamperometric techniques. About 99 % of protection efficiency was achieved by 2 mM concentration of CC in 3.5% NaCl solution.The adsorption of CC on AA6061 surface obeys Langmuir isotherm by following both physisorption and chemisorption mechanism. Variation in the surface morphology of inhibited and uninhibi...

  3. State diagram of copper-aluminium alloys after neutron irradiation

    International Nuclear Information System (INIS)

    It is ascertained that under reactor irradiation of copper-aluminium alloys (18.0-31.2 at% of Al) radiation-induced phase transformations occur, alpha-phase is decomposed into two ones with alpha'-phase precipitation, in gamma2-phase separate regions of its high-temperature disordered modification (gamma1-phase) are formed. Thermal stability of precipitations is investigated, regions of their existence are defined on the state diagram

  4. Hole quality and burr reduction in drilling aluminium sheets

    DEFF Research Database (Denmark)

    Pilny, Lukas; De Chiffre, Leonardo; Piska, Miroslav;

    2011-01-01

    Optimization of the metal drilling process requires creation of minimum amount of burrs and uniform appearance of the drilled holes. In this paper, an experimental investigation was performed on 2 mm sheets of wrought aluminium alloy Al99.7Mg0.5Cu-H24, using 1.6 and 2 mm diameter drills. Cutting ...... drilled holes was fulfilled as well as high productivity achieved. Such optimized process results in a noticeable production cost reduction....

  5. METAL MATRIX COMPOSITES BASED ON ALUMINIUM LITHIUM AND SILICON CARBIDE

    OpenAIRE

    White, J.; Hughes, I; Willis, T.; Jordan, R.

    1987-01-01

    The present study tests the feasibility of producing metal matrix composites based on aluminium-lithium alloys. The first step in this process has been to produce an MMC based on 8090 with SiC. This has been successfully produced by Alcan International using the "Osprey" spray deposition process. The raw billets have been processed initially by extrusion. The tensile properties of this material have been determined and the strength compares favourably with DC cast alloys. Modulus is improved ...

  6. Noncontact ultrasonic thickness measurements of thin aluminium sheet

    International Nuclear Information System (INIS)

    A method has been described for the noncontact ultrasonic thickness measurements of thin aluminium sheets, using a Q-switched ruby laser generation concentric with an annular electro-magnetic acoustic transducer (EMAT) detection to imitate pulse-echo system. The detected waveforms were analyzed with the cut-off frequences of the higher order lamb modes. The results show in a good egreement with micrometer measurements within 2% discrepancy. (authors). 22 refs, 6 figs

  7. Modelling of semi-liquid aluminium flow in extrusion

    OpenAIRE

    G. Skorulski; J. Piwnik

    2007-01-01

    characterizing by low cost. The significant results may be quickly applying using theory of probability. The way of modelling the deformation mechanisms during extrusion of aluminium alloys in semi - liquid phase, the way of preparing samples and experimental technique has been analysed in the following work. On the ground of received results (i.e. registrations of consecutive process steps) the grid of the flow velocity vectors on a flat sample surface was done. It allowed to draw conclusion...

  8. Uranium and thorium behavior at aluminium floating-zone refining

    International Nuclear Information System (INIS)

    Uranium and thorium behaviour during aluminium refining by crystallization from the melt is ascertained. Measurements of of uranium and thorium radioactive impurities content in high-purity aluminiumn samples using the surface α-activity method are carried out. The content of the given impurities happened to be less than 1 x 10-7 mass.%. Such purity satisfies the requirements to materials applied in the low background 71Ge detection system of gallium-germanium solar neutrino detector

  9. Melting Transition of Small Aluminium Clusters Al11-20

    Institute of Scientific and Technical Information of China (English)

    ZHANG Wei; ZHANG Feng-Shou; ZHU Zhi-Yuan

    2007-01-01

    Heat capacities of small aluminium clusters Al11-20 are investigated using MD simulation with empirical manybody Gupta potential. The heat capacities of some clusters Al11, Al12, Al13 and Al19 show well-defined peaks while the heat capacities of Al15-18 indicate a gradual melting transition. The spectra of isomers obtained by quenches along the MD trajectory give good interpretation for those results.

  10. Preparation of polymeric aluminium ferric chloride from bauxite tailings

    OpenAIRE

    Ma D; Guo M; Zhang M

    2013-01-01

    Bauxite tailings are the main solid wastes in the ore dressing process. The Al2O3 and Fe2O3 contents in bauxite tailings can reach 50% and 13% respectively. The present study proposed a feasible method to use bauxite tailings to prepare polymeric aluminium ferric chloride (PAFC), a new composite inorganic polymer for water purification. Bauxite tailings roasted reacting with hydrochloric acid under air, pickle liquor which mainly contains Fe3+, Al3+ was generated, then calcium aluminate...

  11. INVESTIGATION OF THE POTENTIAL PHYSIO-PATOLOGICAL EFFECTS OF ALUMINIUM IN PATIENTS WITH ALZHEIMER SPECIFIC SYMPTOMS

    Directory of Open Access Journals (Sweden)

    Constantin Bǎlǎeț

    2013-06-01

    Full Text Available In the past few years, there has been developed an idea about the connection between the Presence of aluminium in human blood and Alzheimer disease. The goal of our study was to demonstrate that there is a connection between the aluminium in the patients’ blood (who presented specific symptoms and Alzheimer disease’s occurrence, having a physiopathological determination. Aluminium dosage in a group of patients was analyzed (according to some pre-established procedures. 65% of the patients had 1-5% higher than normal values for aluminium level. Aluminium intoxication could lead to syndromes which could affect peoples’ activity. The general physicians must be aware of the need for detecting the aluminium in blood, of interpreting the physiopathological changes and of monitoring these changes in order to detect early symptoms of Alzheimer disease.

  12. RESPONSE OF PHENOLIC METABOLISM INDUCED BY ALUMINIUM TOXICITY IN FAGOPYRUM ESCULENTUM MOENCH. PLANTS.

    Science.gov (United States)

    Smirnov, O E; Kosyan, A M; Kosyk, O I; Taran, N Yu

    2015-01-01

    Buckwheat genus (Fagopyrum Mill.) is one of the aluminium tolerant taxonomic units of plants. The aim of the study was an evaluation of the aluminium (50 μM effect on phenolic accumulation in various parts of buckwheat plants (Fagopyrum esculentum Moench). Detection of increasing of total phenolic content, changes in flavonoid and anthocyanin content and phenylalanine ammonia-lyase activity (PAL) were revealed over a period of 10 days of exposure to aluminium. The most significant effects of aluminium treatment on phenolic compounds accumulation were total phenolic content increasing (by 27.2%) and PAL activity rising by 2.5 times observed in leaves tissues. Received data could be helpful to understand the aluminium tolerance principles and relationships of phenolic compounds to aluminium phytotoxicity. PMID:27025067

  13. Modelling of detonation cellular structure in aluminium suspensions

    Science.gov (United States)

    Briand, A.; Veyssiere, B.; Khasainov, B. A.

    2010-12-01

    Heterogeneous detonations involving aluminium suspensions have been studied for many years for industrial safety policies, and for military and propulsion applications. Owing to their weak detonability and to the lack of available experimental results on the detonation cellular structure, numerical simulations provide a convenient way to improve the knowledge of such detonations. One major difficulty arising in numerical study of heterogeneous detonations involving suspensions of aluminium particles in oxidizing atmospheres is the modelling of aluminium combustion. Our previous two-step model provided results on the effect on the detonation cellular structure of particle diameter and characteristic chemical lengths. In this study, a hybrid model is incorporated in the numerical code EFAE, combining both kinetic and diffusion regimes in parallel. This more realistic model provides good agreement with the previous two-step model and confirms the correlations found between the detonation cell width, and particle diameter and characteristic lengths. Moreover, the linear dependence found between the detonation cell width and the induction length remains valid with the hybrid model.

  14. 68Ga radionuclide generator on the aluminium oxide

    International Nuclear Information System (INIS)

    The method of 68Ga generator on the base of aluminium oxide is supposed. The method includes the preliminarily treatment of the aluminium oxide by NaOH solution (0.1 mol/l) and following dynamical sorption of 68Ge maternal radionuclide on the treated aluminium oxide. Value of the 68Ge sorption makes up more than 97 %. Sorption of 68Ge is proceeding at pH water solution not more than 12, but elution the 68Ga daughterly radionuclide is carried out by HCl solution (0.1 mol/l). Testing of the 68Ga pilot radionuclide preparation shows, that the generator provides the production of 300 eluates of 68Ga preparation with output 50-70 %. The 68Ge impurities in 68Ga eluate makes up 2·10-4 %. Aluminum content in the all 68Ga fractions makes up 1 μg/ml. Influence of HCl concentration in eluent and time interval between elution on the 68Ga and 68Ge breakthrough is studied

  15. Aluminium intake by INAA of hair: The aerosol intoxication pathway

    International Nuclear Information System (INIS)

    Aluminium is present in healthy human organisms in concentrations that appear to be neither useful nor noxious. However, long term higher Al levels can produce severe bone, renal and cerebral troubles. Here we report the results of the first investigation using the Instrumental Neutron Activation Analysis of human hair aimed to assess the Al contamination in workers from aluminium industry due to aerosol inhalation. Seventy five subjects working at 'Alprom' Inc., Slatina, Romania aluminium processing plant were included in this study. The exposed subjects were casters, crane operators and rolling mill operators. Hair samples were washed with acetone-water-water-water-acetone using bi-distilled water and re-distilled-purified p.a. grade acetone and irradiated for 3 min at a thermal neutron flux of 2.3 x 1012 n/cm2s in the VVR-S reactor. Student's t-test showed the arithmetical mean values of all exposed groups to differ of the control group's one with a good statistical confidence level. In most workers the Al concentration in hair is 2 times higher than normal but in one third of the casters and in two of the rolling mill operators it is on average up to 7 times higher. Substantial Al overload can cause severe osteoporosis or encephalopathies even after retirement from activity. Protection filtering masks and medical therapy based on strong chelant drug deferoxamine are recommended, (authors)

  16. Mechanical behaviour of nitrogen-implanted aluminium alloys

    Energy Technology Data Exchange (ETDEWEB)

    Guzman, L. [Centro Materiali e Biofisica Medica, Trento (Italy); Bonini, G. [Dipt. di Ingegneria Nucleare del Politecnico, Milano (Italy); Adami, M. [Dipt. di Meccanica Strutturale, Univ. degli Studi di Trento (Italy); Ossi, P.M. [Dipt. di Ingegneria Nucleare del Politecnico, Milano (Italy)]|[Trento Univ., Povo (Italy). Dipt. di Fisica; Miotello, A. [Ist. Nazionale per la Fisica della Materia, Univ. degli Studi di Trento (Italy)]|[Trento Univ., Povo (Italy). Dipt. di Fisica; Vittori-Antisari, M. [ENEA, C.R. Casaccia, Settore Nuovi Materiali, Roma (Italy); Serventi, A.M. [ENEA, C.R. Casaccia, Settore Nuovi Materiali, Roma (Italy); Voltolini, E. [Centro Materiali e Biofisica Medica, Trento (Italy)

    1996-09-01

    The effect of nitrogen implantation into pure aluminium has been extensively explored, taking into account the variation of several physical and technological properties of the implanted layer. In particular, the formation of aluminium nitride, which occurs under specific choices of the implantation parameters, is associated with an increase in hardness. In this work, we consider two Al alloys (Al-7075 and Al-2011), frequently employed in the mechanical industry, with properties strongly dependent on the thermomechanical treatment. Molecular nitrogen bombardment at 150 keV (75 keV N{sup +}) was employed, up to a total dose of 3.10{sup 17} N cm{sup -2}, varying the substrate temperature from 373 to 473 K. The samples were then characterized with respect to composition, structure, morphology, microhardness, scratch resistance (also performing multi-pass testing) and friction coefficient. The results were interpreted within the framework of micromechanical models describing the hardness of thin coatings deposited onto soft substrates; the microhardness of the implanted layer increased by a factor of five. It appears that nitrogen-implanted aluminium alloy layers, in spite of their shallow thickness, behave better than hard TiN coated surfaces. Care must be taken to implant both alloys at the lowest possible temperature to avoid degradation of the substrate properties. (orig.)

  17. Welding metallurgy of aluminium for radiation tube of reactor

    International Nuclear Information System (INIS)

    The metallurgy of TIG weldment in aluminium alloy was examined based on physical metallurgy characteristics. The presence of weld defects have been detected by x-ray radiographic and metallographic methods. The lack of penetration in the aluminium weldment was possibly caused by the formation of aluminium oxide layer, insufficient heating flow and fast speed of work piece rotation. Segregation of major elements such as Mg and Si were varied between the weld zone and parent metal depending on the heat input during welding. Microstructure and microhardness across the weldment were markedly changed by heat-treatments. Minimum hardness was found in the heat-affected zone (HAZ) - fusion zone boundary and maximum hardness was found in the fusion zone. Both these extremes can produce premature failure of the weldment. Such failure especially embrittlement cracking could be hindered by heat-treated at 4130C, 2 1/2 hours and furnace cooled, where the distribution of hardness has been minimized and homogenized. (author)

  18. Analysis of Orthogonal Cutting of Aluminium-based Composites

    Directory of Open Access Journals (Sweden)

    P. Ravinder Reddy

    2002-10-01

    Full Text Available A turning test on aluminium-based metal-matrix composites (MMCs (aluminium-30% silicon carbide was performed with K-20 carbide tool material and wear patterns and the wear land growth rates were analysed to evaluate the wear characteristics and to classify the relationship between the physical (mechanical properties and the flank wear of cutting tools. The study was also extended to the machining aspects and the width of cuts on MMCs and the influence of various cutting parameters. The experiments were conducted to measure the temperature along the cutting tool edge using thermocouple at various cutting speeds, and depth of cuts, keeping the feed rate constant while turning with K-20 carbide cutting tool. The finite-element method was used to simulate the orthogonal cutting of aluminium-based MMCs. The heat generation at the chip-tool interface, frictional heat generation at the tool flank, and the heat generation at the work tool interface were calculated analytically and imposed as boundary conditions. The analysis of the steady-state heat transfer was carried out and the temperature distribution at cutting edge, shear zone, and interface regions have been reported.

  19. The Effect of Thickness of Aluminium Films on Optical Reflectance

    Directory of Open Access Journals (Sweden)

    Robert Lugolole

    2015-01-01

    Full Text Available In Uganda and Africa at large, up to 90% of the total energy used for food preparation and water pasteurization is from fossil fuels particularly firewood and kerosene which pollute the environment, yet there is abundant solar energy throughout the year, which could also be used. Uganda is abundantly rich in clay minerals such as ball clay, kaolin, feldspar, and quartz from which ceramic substrates were developed. Aluminium films of different thicknesses were deposited on different substrates in the diffusion pump microprocessor vacuum coater (Edwards AUTO 306. The optical reflectance of the aluminium films was obtained using a spectrophotometer (SolidSpec-3700/DUV-UV-VIS-NIR at various wave lengths. The analysis of the results of the study revealed that the optical reflectance of the aluminium films was above 50% and increased with increasing film thickness and wavelength. Thus, this method can be used to produce reflector systems in the technology of solar cooking and other appliances which use solar energy.

  20. Effect of ultrasonic energy on nanoscale interfacial structure in copper wire bonding on aluminium pads

    International Nuclear Information System (INIS)

    The effect of ultrasonic vibration on nanoscale interfacial structure of thermosonic copper wire bonding on aluminium pads was investigated. It was found that bonding strength was determined by the extent of fragmentation of a native aluminium oxide overlayer (5-10 nm thick) on aluminium pads, forming paths for formation of intermetallic compound CuAl2 in areas of direct contact of bonded metal surfaces. The degree of fracture of the oxide layer was strongly affected by a level of ultrasonic power.

  1. Subgrain Growth, Recovery Kinetics and Nucleation of Recrystallization of Cold Deformed Aluminium Alloys

    OpenAIRE

    Bunkholt, Sindre

    2013-01-01

    Phenomena related to annealing of aluminium alloys are among the least understood in aluminium metallurgy but very important for industrial thermo-mechanical processing i.e. deformation and annealing. Physical models are used to predict recovery and recrystallization behaviour, and associated material properties, industrially. However, alloy development, e.g. to incorporate more recycled aluminium, has shown that current softening models are not satisfactory. Thus, improvements do require a b...

  2. Selected properties of the aluminium alloy base composites reinforced with intermetallic particles

    OpenAIRE

    M. Adamiak

    2005-01-01

    Purpose: The main aim of this work is to investigate two types of intermetallics TiAl and Ti3Al as reinforcement and their influence on selected properties and microstructure of aluminium matrix composites.Design/methodology/approach: Aluminium matrix composites were produced employing the atomised aluminium alloy AA6061 as metal matrix, when as reinforcement TiAl and Ti3Al intermetallics particles were used. The powders were cold pressed and then hot extruded. To evaluate the effect of mecha...

  3. Anisotropic behaviour law for sheets used in stamping: A comparative study of steel and aluminium

    OpenAIRE

    Sinou, Jean-Jacques; Macquaire, Bruno

    2003-01-01

    International audience For a car manufacturer, reducing the weight of vehicles is an obvious aim. Replacing steel by aluminium moves towards that goal. Unfortunately, aluminium's stamping numerical simulation results are not yet as reliable as those of steel. Punch-strength and spring-back phenomena are not correctly described. This study on aluminium validates the behaviour law Hill 48 quadratic yield criterion with both isotropic and kinematic hardening. It is based on the yield surface ...

  4. Electrodeposition of aluminium film on P90 Li-Al alloy as protective coating against corrosion

    OpenAIRE

    U. Bardi; Caporali, S; M. Craig; A. Giorgetti; Perissi, I; Nicholls, J. R.

    2009-01-01

    In this paper we report on the electrodeposition of thin aluminium layers on P90 lithium–aluminium alloy at room temperature from a chloroaluminate ionic liquid (1-butyl-3-methyl imidazolium heptachloroaluminate [BMIm]Al2Cl7). We found that the treatment of the P90 sample's surface is a key point to obtain good quality coatings. On freshly mechanically polished surfaces, thin (about 24 µm), homogeneous and dense aluminium layers were obtained at 10 µm h− 1 deposition rate. F...

  5. Improvement in Wear Properties of a Hypereutectic Aluminium Silicon Alloy with Manganese

    OpenAIRE

    Prabhkiran Kaur; D.K. Dwivedi; P.M. Pathak; Sunil Kumar

    2014-01-01

    Improvement in wear properties of rare earth Cerium base hypereutectic Aluminium-Silicon alloy with Manganese modification has been reported in this paper. Wear studies were carried out on cast samples of hypereutectic Aluminium-Silicon alloy (Al-Si) with rare earth Cerium oxide (CeO2) and Manganese (Mn) modification. Final wear properties of rare earth Cerium oxide and Manganese modified hypereutectic Aluminium Silicon alloy were compared with the values of author?s previous work on rare ear...

  6. Insight into the cellular fate and toxicity of aluminium adjuvants used in clinically approved human vaccinations

    OpenAIRE

    Mold, M; Shardlow, E; Exley, C.

    2016-01-01

    Aluminium adjuvants remain the most widely used and effective adjuvants in vaccination and immunotherapy. Herein, the particle size distribution (PSD) of aluminium oxyhydroxide and aluminium hydroxyphosphate adjuvants was elucidated in attempt to correlate these properties with the biological responses observed post vaccination. Heightened solubility and potentially the generation of Al3+ in the lysosomal environment were positively correlated with an increase in cell mortality in vitro, pote...

  7. Determination of aluminium contents in selected food samples by instrumental neutron activation analysis

    International Nuclear Information System (INIS)

    Food and food products are the main sources of Aluminium entering the human body. In order to know aluminium contents in food and food products, selected 26 samples from local market were analyzed by instrumental neutron activation analysis (INAA) using reactor neutrons and high resolution gamma-ray spectrometry. INAA using 1,779 keV γ-ray of 28Al (2.24 min) was used for aluminium concentrations in the range of 33-529 mg kg-1. Two NIST standard reference materials (SRMs) and two IAEA reference materials (RMs) were analyzed by INAA for quantification of aluminium as a part of method validation. (author)

  8. Low temperature oxidation of niobium alloy with silicon-aluminium coating

    International Nuclear Information System (INIS)

    Using the gravimetry methods heat resistance of niobium-titanium-aluminium alloy in the air and at 700 deg C in the initial state and when it is protected by silicide-aluminium coatings (with variable content of aluminium) is investigated. Using X-ray diffraction and micro X-ray diffraction analyses, mechanisms of the alloy oxidation and the coating protective effect are studied. The role of aluminium in the formation of coatings is analyzed and according to bend tests the plasticity of the coatings is evaluated

  9. Wear and chemistry of zirconium-silicate, aluminium-silicate and zirconium-aluminium-silicate glasses in alkaline medium

    International Nuclear Information System (INIS)

    A study of the chemical durability, in alkaline solutions, of zirconium silicate, aluminium silicate, zirconium/aluminium silicate glasses as a function of glass composition is carried out. The glasses were tested using standard DIN-52322 method, where the glass samples are prepared in small polished pieces and attacked for 3 hours in a 800 ml solution of 1N (NaOH + NA2CO3) at 970C. The results show that the presence of ZrO2 in the glass composition increases its chemical durability to alkaline attack. Glasses of the aluminium/zirconium silicate series were melted with and without TiO2. It was shown experimentally that for this series of glasses, the presence of both TiO2 and ZrO2 gave better chemical durability results. However, the best overall results were obtained from the simpler zirconium silicate glasses, where it was possible to make glasses with higher values of ZrO2. (Author)

  10. Effect of ageing on the mechanical behaviour of aluminium alloy AA2009 reinforced with SIC particles

    International Nuclear Information System (INIS)

    A study of the mechanical behaviour of an aluminium matrix composite (AA2009) reinforced with 15 volume percent of SiC particles has been carried out. The ageing kinetic for this material has been evaluated at two different ageing temperatures (170 and 190 degree centigrade). The hardness peaks for the two different precipitation sequences existing in the matrix alloy have been identified. The mechanical behaviour of the composite was also evaluated for the different thermal conditions (as-received and aged). This research has been completed with the identification of the fracture mechanisms by means of observation with scanning electron microscopy (SEM) both of the fracture surface and transversal sections of them. In addition, transmission electron microscopy (TEM) of the treated composites has been used to determine the influence of the SiC particles on the distribution of strengthening phases precipitated in the matrix. (Author) 14 refs

  11. The research of properties of Eu3+-doped cadmium aluminium silicate glass

    Science.gov (United States)

    Chen, Yue-e.; Hou, Lan-tian; Song, Zhao-yuan

    2008-11-01

    We have prepared (40SiO2-14Al2O3-(40-x) CdO-2Li2O-2K2O-2Na2O -x Eu2O3) cadmium aluminium silicate glasses doped with europium by high temperature solid-state reaction method. The absorption spectra, excitation spectra, emission spectra are obtained. With the increase of Eu2O3, the absorption peaks are founded increasing to the best doped concentration and then reducing, which is nonlinear relationship. The charge-transfer band is moved to 320 nm due to the addition of Cd2+. We can see that the ratio of peak in 591 nm and 615 nm is 0.6-0.75 in general, and is unrelated to doped concentration. By changing concentration of Eu3+.We can adjust and mix different intensity of light according to the demand.

  12. Studies of Splat Formation of Copper and Copper Aluminium on Ceramic Substrate in Plasma Spray Process

    Science.gov (United States)

    Tran, A. T. T.; Hyland, M. M.; Fukumoto, M.; Munroe, P.

    2016-01-01

    Of the substrate-related factors that will influence splat formation, alloying elements has been little studied. In the present work, we have examined the role of alloying elements in controlling the extent of splashing of plasma-sprayed splats. Splats of copper (Cu) and copper alloyed with Al and Zr were deposited by plasma spray or as free-falling droplets. The splat formation and splat-substrate interfaces were characterized using SEM and FIB. It was found that the presence of aluminium in plasma-sprayed Cu-10%Al increased the portion of favorable disk-shaped splats compared to pure copper. It was also found that the disk-shaped splat proportion of Cu-10%Al at room temperature is nearly identical to that of Cu splat at 300 °C, indicating that the addition of Al in the alloy leads to the improvement of splat formation, correlating with the improvement in the interface bonding with the substrate.

  13. Protection against corrosion in marine environments of AA6060 aluminium alloy by cerium chlorides

    International Nuclear Information System (INIS)

    Lanthanide salts are being considered as an environmentally friendly alternative to the classic systems based on chromates. The addition of small concentrations of cerium chloride to aerated aqueous 3.5% NaCl solution inhibits uniform and pitting corrosion processes of AA6060. Full immersion tests combined with different electrochemical techniques were involved to determine the protection degree and the inhibition character supplied by the cerium ion. Their microscopic and compositional features have been analyzed using SEM and EDS spectra. The results obtained show that the protective layer has heterogeneous composition. An alumina layer covers the aluminium matrix while dispersed cerium-rich islands deposited over the cathodic sites of the alloy. In the case of AA6060, α-Al(Fe,Mn)Si acts as permanent cathodic sites.

  14. LASER CLADDING ON ALUMINIUM BASE ALLOYS

    OpenAIRE

    Pilloz, M.; Pelletier, J; Vannes, A.; Bignonnet, A.

    1991-01-01

    laser cladding is often performed on iron or titanium base alloys. In the present work, this method is employed on aluminum alloys ; nickel or silicon are added by powder injection. Addition of silicon leads to sound surface layers, but with moderated properties, while the presence of nickel induces the formation of hard intermetallic compounds and then to an attractive hardening phenomena ; however a recovery treatment has to be carried out, in order to eliminate porosity in the near surface...

  15. Fluorometric determination of aluminium (III) and cadmium (II) by solvent extraction of the ternary complex composed of metal ion, 8-hydroxy-5-quinolinesulfonic acid, and methyltrioctylammonium ion

    Energy Technology Data Exchange (ETDEWEB)

    Kondoh, Yukihiro; Kataoka, Masamitsu; Kambara, Tomihito (Hokkaido Univ., Sapporo (Japan). Faculty of Science)

    1982-02-01

    A fluorometric micro determination of aluminium (III) and cadmium (II) using the formation of metal-8-hydroxy-5-quinolinesulfonic acid-capriquat (methyltrioctylammonium) ternary complex is described. These complexes are easily extracted into chloroform phase and the extract emits a strong fluorescence. Spectra of aluminium (III) and cadmium (II) ternary complexes have the excitation maximum at 396 nm and 400 nm, and emission maximum at 501 nm and 524 nm, respectively. Fluorescence intensity of the aluminium (III) and cadmium (II) ternary complexes extracted into chloroform showed the constant and maximum values in the pH range of aqueous phase from 5.3 to 8.5 and 8.1 to 8.5, respectively. The calibration curves for aluminium (III) and cadmium (II) show good proportionality in the concentration range from 0.5 to 5.0 and 1.0 to 50.0 ..mu..g, respectively. The relative standard deviation observed with four measurements was found to be 1.8% for 0.5 ..mu..g of aluminium (III) and 1.1% for 10.0 ..mu..g of cadmium (II). The effect of diverse ions is studied and a 25-fold amount of Cu(II), Ni(II), Fe(II), Fe(III) in weight gave errors, however, the interferences were easily eliminated by the addition of appropriate masking agent. In the determination of cadmium (II), an equal amount of Co(II), Ni(II), Mn(II), Fe(III) and twice amount of Al(III) gave negative errors, however, the interference of Fe(III) and Al(III) were also eliminated as above.

  16. The effect of anions in the fluorimetric determination of uranium after extraction from acid-deficient aluminium nitrate solution

    International Nuclear Information System (INIS)

    The effect of perchlorate, chloride, sulphate, phosphate and fluoride on the fluorimetric determination of uranium after the extraction of uranium into methyl isobutyl ketone from acid-deficient aluminium nitrate solution has been established. Recoveries of uranium from perchlorate and sulphate media after addition of 1 ml of 15 M nitric acid are 100%. Chloride interferes, and a correction must be made to compensate for the anion effect. Phosphate and fluoride in amounts up to 25 mg give recoveries of at least 95%. The anion effect may be minimized by increasing the volume of the organic phase. (author)

  17. Comparison of different methods to include recycling in LCAs of aluminium cans and disposable polystyrene cups.

    Science.gov (United States)

    van der Harst, Eugenie; Potting, José; Kroeze, Carolien

    2016-02-01

    Many methods have been reported and used to include recycling in life cycle assessments (LCAs). This paper evaluates six widely used methods: three substitution methods (i.e. substitution based on equal quality, a correction factor, and alternative material), allocation based on the number of recycling loops, the recycled-content method, and the equal-share method. These six methods were first compared, with an assumed hypothetical 100% recycling rate, for an aluminium can and a disposable polystyrene (PS) cup. The substitution and recycled-content method were next applied with actual rates for recycling, incineration and landfilling for both product systems in selected countries. The six methods differ in their approaches to credit recycling. The three substitution methods stimulate the recyclability of the product and assign credits for the obtained recycled material. The choice to either apply a correction factor, or to account for alternative substituted material has a considerable influence on the LCA results, and is debatable. Nevertheless, we prefer incorporating quality reduction of the recycled material by either a correction factor or an alternative substituted material over simply ignoring quality loss. The allocation-on-number-of-recycling-loops method focusses on the life expectancy of material itself, rather than on a specific separate product. The recycled-content method stimulates the use of recycled material, i.e. credits the use of recycled material in products and ignores the recyclability of the products. The equal-share method is a compromise between the substitution methods and the recycled-content method. The results for the aluminium can follow the underlying philosophies of the methods. The results for the PS cup are additionally influenced by the correction factor or credits for the alternative material accounting for the drop in PS quality, the waste treatment management (recycling rate, incineration rate, landfilling rate), and the

  18. Phosphorus binding by aluminium in sediment: a tool for restoring water quality in the Baltic Sea and other brackish surface waters

    OpenAIRE

    Huser, Brian

    2014-01-01

    Lake and sea sediments act as stores for historical inputs of pollutants from both direct and diffuse sources including urbanization, agriculture, municipal and indus- trial waste waters, among others. Historical accumulation in sediments can provide a continual source of phosphorus to the water column for decades or longer after external sources have been controlled. Addition of metal salts, e.g. aluminium salts, can permanently bind this excess phosphorus in the sediment, thereby reducing i...

  19. Enhancement of wear and ballistic resistance of armour grade AA7075 aluminium alloy using friction stir processing

    OpenAIRE

    I. Sudhakar; V. Madhu; G. Madhusudhan Reddy; K. Srinivasa Rao

    2015-01-01

    Industrial applications of aluminium and its alloys are restricted because of their poor tribological properties. Thermal spraying, laser surfacing, electron beam welding are the most widely used techniques to alter the surface morphology of base metal. Preliminary studies reveal that the coating and layering of aluminium alloys with ceramic particles enhance the ballistic resistance. Furthermore, among aluminium alloys, 7075 aluminium alloy exhibits high strength which can be compared to tha...

  20. Influence of Alkali Treatment on the Surface Area of Aluminium Dross

    Directory of Open Access Journals (Sweden)

    N. S. Ahmad Zauzi

    2016-01-01

    Full Text Available Aluminium dross is an industrial waste from aluminium refining industry and classified as toxic substances. However, the disposal of dross as a waste is a burden to aluminium manufacturer industries due to its negative effects to the ecosystem, surface, and ground water. Therefore the purpose of this study is to evaluate the influence of sodium hydroxide (NaOH on the surface area and pore size of aluminium dross. There were 3 stages in the treatment activities, which were leaching, precipitation, and calcination process. The optimum result from this study was the surface area of aluminium dross increases from 10.1 m2/g up to 80.0 m2/g at 40°C, 1% NaOH, and 15-minute reaction time. Thus, aluminium dross has a potential to be converted into other useful material such as catalyst and absorbent. The benefit of this research is that the hazardous industrial waste can be turned into wealth to be used in other applications such as in catalytic activities and absorber in waste water treatment. Further investigation on the physicochemical of aluminium dross with different acid or alkali should be conducted to get deeper understanding on the aluminium dross as a catalyst-type material.

  1. Void formation in pure aluminium irradiated with high-energetic electron beams and gamma-quanta

    DEFF Research Database (Denmark)

    Gan, V. V.; Ozhigou, L. S.; Yamnitsky, V. A.; Singh, Bachu Narain; Leffers, Torben; Bilde-Sørensen, Jørgen

    The spatial distribution of displaced atoms and helium atoms and also the spectra of damaging energies of primary displaced atoms in a thick aluminium target irradiated with electrons of 225 MeV energy were calculated. Pure aluminium (99.9999%) irradiated up to 0.04 dose was studied by electron...

  2. The effect of aluminium chlorhydrate on sweat gland activity in cattle.

    Science.gov (United States)

    Rees-Jones, A M; Jenkinson, D M

    1978-03-01

    Topical application of aluminium chlorhydrate had no appreciable antiperspirant action on the epitrichial glands of cattle. There was no evidence of penetration of the salt into the dermis or of any change in the morphology of the glands. It is probable that the antiperspirant activity of aluminium chlorhydrate in the human axilla, is only on the atrichial glands. PMID:632617

  3. Fatigue testing of large scale details of a large size aluminium surface effect ship

    NARCIS (Netherlands)

    Dijkstra, O.D.; Vredeveldt, A.W.; Janssen, G.Th.M.; Ortmans, P.

    1998-01-01

    The paper presents the results of two large scale fatigue tests on a detail of an aluminium surface effect ship. The overall dimensions of the specimens were: length 4.8 m, height 3.2 m and width 1.5 m (equal to the main frame spacing). The specimens consist of an aluminium structure of welded plate

  4. Synthesis and reactivity of aluminium nitride obtained by action of ammonia on alumina

    International Nuclear Information System (INIS)

    Aluminium nitride is a ceramic with potential nuclear applications because of its exceptional structural resistance to neutrons. To improve quality and reactivity a new preparation process by reaction between ammonia and alumina is presented. The aluminium nitride thus obtained, white colored, is pure and its reactivity gives an useful product for a lot of synthesis in the area of nitrided ceramics and glasses

  5. Synthesis and reactivity of aluminium nitride obtained by action of ammonia on alumina

    Energy Technology Data Exchange (ETDEWEB)

    Rocherulle, J.; Guyader, J.; Verdier, P.; Laurent, Y.

    1985-01-01

    Aluminium nitride is a ceramic with potential nuclear applications because of its exceptional structural resistance to neutrons. To improve quality and reactivity a new preparation process by reaction between ammonia and alumina is presented. The aluminium nitride thus obtained, white colored, is pure and its reactivity gives an useful product for a lot of synthesis in the area of nitrided ceramics and glasses.

  6. Insight into the cellular fate and toxicity of aluminium adjuvants used in clinically approved human vaccinations

    Science.gov (United States)

    Mold, Matthew; Shardlow, Emma; Exley, Christopher

    2016-01-01

    Aluminium adjuvants remain the most widely used and effective adjuvants in vaccination and immunotherapy. Herein, the particle size distribution (PSD) of aluminium oxyhydroxide and aluminium hydroxyphosphate adjuvants was elucidated in attempt to correlate these properties with the biological responses observed post vaccination. Heightened solubility and potentially the generation of Al3+ in the lysosomal environment were positively correlated with an increase in cell mortality in vitro, potentially generating a greater inflammatory response at the site of simulated injection. The cellular uptake of aluminium based adjuvants (ABAs) used in clinically approved vaccinations are compared to a commonly used experimental ABA, in an in vitro THP-1 cell model. Using lumogallion as a direct-fluorescent molecular probe for aluminium, complemented with transmission electron microscopy provides further insight into the morphology of internalised particulates, driven by the physicochemical variations of the ABAs investigated. We demonstrate that not all aluminium adjuvants are equal neither in terms of their physical properties nor their biological reactivity and potential toxicities both at the injection site and beyond. High loading of aluminium oxyhydroxide in the cytoplasm of THP-1 cells without immediate cytotoxicity might predispose this form of aluminium adjuvant to its subsequent transport throughout the body including access to the brain. PMID:27515230

  7. The role of magnesium in the electrochemical behaviour of 5XXX aluminium-magnesium alloys

    NARCIS (Netherlands)

    Flores Ramirez, J.R.

    2006-01-01

    An investigation concerning the effects of magnesium on the intergranular corrosion susceptibility of AA5XXX aluminium alloys was carried out. In the present work, magnesium is found to be highly mobile in the bulk metal as well as in the aluminium oxide. This mobility is also found to be dependent

  8. European welding technology for an Australian yacht in aluminium; Soudage a l'europeenne pour un yacht australien en aluminium

    Energy Technology Data Exchange (ETDEWEB)

    Anon.

    2005-02-01

    It is a European welding technology which has been retained for the Australian shipbuilding yard: 'Shipworks' for manufacturing a luxury yacht in aluminium. This yacht has been manufactured under the American standards specifications. (O.M.)

  9. TEM microstructure investigations of aluminium alloys used for laser alloying

    Directory of Open Access Journals (Sweden)

    K. Labisz

    2012-12-01

    Full Text Available Purpose: In this paper there are presented results of Transmission Electron Microscope investigation concerning the structure of the AlSi7Cu4 cast aluminium alloy using for alloying and remelting with the high power diode laser (HPDL. There are also presented the results of the thermo-derivative analysis performed using the UMSA (Universal Metallurgical Simulator and Analyser device, allowing to determine the specific points of the solidifying alloy, what is helpful for phase determination occurred in this alloy. In this work especially the changes of the precipitation type, size and shape were determined.Design/methodology/approach: The investigations were performed using electron microscopy for the microstructure and phases determination. By mind of the transmission electron microscopy, especially selected area diffraction method appliance it was possible to determine the phases occurred in the alloy in the as cast state. The morphology and size of the Mg2Si was also possible to determine as well the lattice parameters for this phase.Findings: : The reason of this work was also to present the laser treatment technology, which will be used for further alloying and remelting with ceramic powders – especially carbides and oxides. Particularly the overview will be directed on the laser power to achieve good layer hardness for protection of this hot work tool steel from losing their work stability and to make the tool surface more resistant to action in external conditions. The structure of the surface laser tray changes in a way, that there are very high roughness of the surface zone and the flatness or geometry changes in an important manner, crucial for further investigation.Research limitations/implications: The aluminium samples were examined metallographically using transmission electron microscope with different image techniques.Practical implications: Developing of new technology with appliance of Al alloys, High Power Diode Laser and

  10. Regularities in aluminium and indium chemisorption on chelating polymeric sorbents

    International Nuclear Information System (INIS)

    Complexation properties of synthesized polymer chelate sorbents: substituted of polystyrene-azo-pyrocatechol are investigated and correlations between pK'OH of functional groups of sorbents as well as pH50 values of chelation and constants of stability (lgKstab) are established for studying regularities of effect of structure and acid-base properties of functional groups of sorbents on the parameters of Al3+ and In3+ chemical sorption. Established correlations make it possible to predict the physicochemical parameters of sorbents and sorption of metal ions with the aim of separation and concentration of aluminium and indium micro account from the objects of different origin

  11. Effects of silicon on gastrointestinal absorption of aluminium

    Energy Technology Data Exchange (ETDEWEB)

    Edwardson, J.A.; Moore, P.B.; Ferrier, I.N.; Lilley, J.S.; Newton, G.W.A.; Barker, J.; Templar, J.; Day, J.P.

    1993-07-24

    The reported geographical association between Alzheimer's disease and levels of aluminium (Al) in water supplies may reflect the inverse relation between Al and silicon (Si) concentrations in water, and the potential for Si to reduce the bioavailability of the metal. The authors tested this hypothesis using isotopic [sup 26]Al tracer administered orally to five healthy volunteers in the presence and absence of Si. Dissolved Si, at a concentration found in some water supplies reduced the peak plasma [sup 26]Al concentration to 15% of the value obtained in the absence of Si. The results indicate that dissolved Si is an important factor in limiting the absorption of dietary Al.

  12. Interface reaction in aluminium matrix composite at laser welding

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    Interface reaction of SiCw/6061Al aluminium matrix composite subjected to laser welding was studied. It is pointed out that the main reason for bad weldability of the material is concerned with the interface reaction during the welding. Effects of welding parameters on interface reaction were also investigated. The results show that the interface bonding state can be improved by laser beam, and the main welding parameter affecting the strength of weld is laser output power. The smaller the output power, the lower the extent of interface reaction and the better the mechanical properties.

  13. Fatigue behaviour of 6061 aluminium alloy and its composite

    OpenAIRE

    Hwa, Ping

    2001-01-01

    Fatigue behaviour of an artificial aged powder metallurgy 6061 aluminium alloy, and a composite made of this alloy with 15% volume fraction of SiCp was investigated. The alloy was subjected to T6 heat treatment, as was the composite material chosen (which incorporated SiC particles of average size 30pm). An extensive experimental programme was carried out in which fatigue lives were determined using load-controlled axial loading of unnotched cylindrical samples, at stress ratios of-1 and 0.1....

  14. Slip lines in scandium and lithium containing aluminium alloys

    International Nuclear Information System (INIS)

    Intensive slip lines in cold rolled sheets of scandium or lithium containing aluminium base alloys are under study. Slip lines are shown to be the places of concentrated shear strain which arise due to the occurrence of secondary δ'(Al3Li) and Al3Sc particles completely coherent to the matrix. The formation of slip lines has a detrimental effect on cold rolled sheet mechanical properties after heat hardening. To avoid the appearance of slip lines it is necessary to roll sheets with low reductions in area and to choose appropriate conditions of intermediate heat treatments. 5 refs., 5 figs., 2 tabs

  15. Damage of repeatedly nitrocarburised steel dies for aluminium extrusion

    OpenAIRE

    Firrao, Donato; Scavino, Giorgio; Matteis, Paolo

    2009-01-01

    The dies employed for the hot extrusion of aluminium alloys are subjected to repeated cycles of nitriding, or nitrocarburising, after service periods of given length. Three dies, fabricated with ISO X40CrMoV5-1 (AISI H13) steel and liquid nitrocarburised, were examined either in the asfabricated condition, or after one service period, or after 12 nitrocarburising and service cycles (end of life). Samples cut from the die subjected to one service period were re-nitrocarburised for increasing d...

  16. Physical model of aluminium refining process in URC-7000

    Directory of Open Access Journals (Sweden)

    M. Saternus

    2009-07-01

    Full Text Available The paper presents short characteristics of the most frequently used reactors for the continuous refining of aluminium and its alloys. Refining depends on the flow rate of refining gas. It influences the shape and size of gas bubbles. So the physical model was created to determine the level of gas bubble dispersion in liquids. Schemes of gas dispersion in liquid metal were presented taking into consideration that the gas flow rate is changing from 2 to 30 dm3/min. The range selection of the flow rate of refining gas value for five patterns of the dispersion (no dispersion, minimum, intimate, uniform and overdispersion was also done.

  17. The fracture of boron fibre-reinforced 6061 aluminium alloy

    Science.gov (United States)

    Wright, M. A.; Welch, D.; Jollay, J.

    1979-01-01

    The fracture of 6061 aluminium alloy reinforced with unidirectional and cross-plied 0/90 deg, 0/90/+ or - 45 deg boron fibres has been investigated. The results have been described in terms of a critical stress intensity, K(Q). Critical stress intensity factors were obtained by substituting the failure stress and the initial crack length into the appropriate expression for K(Q). Values were obtained that depended on the dimensions of the specimens. It was therefore concluded that, for the size of specimen tested, the values of K(Q) did not reflect any basic materials property.

  18. Determination of phosphorus in hypereutectic aluminium-silicon alloys.

    Science.gov (United States)

    Mukai, K

    1972-04-01

    A reproducible method is described for determination of small amounts of phosphorus (from 0.0005% to 0.02%) in hypereutectic aluminium-silicon complex alloys. The method permits the separate determination of phosphorus in acid-soluble and acid-insoluble fractions. Phosphomolybdate is extracted with n-butanol-chloroform solvent mixture and back-extracted with a btannous chloride reducing solution. The phosphorus content of a sample cut into small pieces decreases during storage; loss of phosphorus is negligible on acid dissolution under oxidizing conditions. PMID:18961077

  19. Tailored Aluminium based Coatings for Optical Appearance and Corrosion Resistance

    DEFF Research Database (Denmark)

    Aggerbeck, Martin

    that the roughness after etching increases with higher amounts of alloying elements (especially iron and silicon). Proper polishing requires some alloy hardness, while alloy purity is required for a glossy appearance after anodisation. Magnetron sputtered aluminium based coatings containing up to 18 wt...... the optical effect of partially oxidised intermetallics and the subsurface morphology after anodisation. It was suggested, that the darkening of the anodised specimens happened due to roughness of the oxide-substrate interface causing light trapping and optical scattering and absorption by the...

  20. Multi-element study in aluminium by activation analysis technique

    International Nuclear Information System (INIS)

    The instrumental activation analysis is a technique relatively quickly that help to know the elemental composition of materials. It is used mainly in the trace elements determination but in the case of major elements it is necessary to make some considerations as the different nuclear reactions carried out due to the neutron flux is a mixture of thermal and fast neutrons. This could be interpreted for the presence and or erroneous quantification about some elements. In this work, is described the way in which was analyzed a container piece with approximately a 85% of aluminium. The elements Zn, Mn, Sb, Ga, Cu, Cl and Sm were determined. (Author)

  1. Modeling of recrystallization texture of aluminium: symmetric and asymmetric rolling

    Science.gov (United States)

    Wierzbanowski, K.; Kotra, M.; Wronski, M.; Sztwiertnia, K.; Wronski, S.; Lodini, A.

    2015-04-01

    In some metallic materials the dominating recrystallization mechanism can be described by the oriented growth behaviour. Phenomenological laws state that in selected materials only these nuclei grow intensively which have a given misorientation relation with the deformed matrix. This description is frequently verified in f.c.c. metals and generally reported misorientations correspond approximately to 400 rotation around the axis. Basing on the above ideas the recrystallization model, including the compromise condition, was formulated and applied to the study of recrystallization textures of rolled polycrystalline aluminium.

  2. Design considerations for HFQ® hot stamped aluminium structural panels

    Directory of Open Access Journals (Sweden)

    Foster Alistair

    2015-01-01

    Full Text Available HFQ is a deep drawing process for alloyed aluminium sheet that can be used to produce complex-stamped forms while maintaining the high-strength of 6xxx and 7xxx alloys. By adopting a strategy to design for HFQ at the platform level, designers can reduce part count (thereby reducing cost and weight, reduce gauge (thereby reducing weight, and improve part packaging. Two simple design examples are given to assist designers in evolving traditionally formed panel designs to HFQ formed solutions. Example features are used to illustrate the effect of geometry, thickness and strength on the final structural component.

  3. Tailored Aluminium based Coatings for Optical Appearance and Corrosion Resistance

    OpenAIRE

    Aggerbeck, Martin; Ambat, Rajan

    2014-01-01

    I dette projekt blev muligheden for at designe aluminiumsbaserede coatings undersøgt med fokus på hvordan den kemiske sammensætning og overfladens beskaffenhed påvirker den visuelle fremtoning og de basiske korrosionsegenskaber med titan anvendt som det primære legeringselement. De primære resultater og diskussioner fra dette arbejde præsenteres i form af i bilag som fire artikelmanuskripter indsendt til publikation i tidsskrifter. Anvendelsen af aluminium er bred, fra transportmidler, bygnin...

  4. The effect of atmospheric corona treatment on AA1050 aluminium

    DEFF Research Database (Denmark)

    Jariyaboon, Manthana; Møller, Per; Dunin-Borkowski, Rafal E.;

    2010-01-01

    The effect of atmospheric corona discharge on AM 050 aluminium surface was investigated using electrochemical polarization, SEM-EDX, FIB-SEM. and XPS. The corona treatment was performed with varying time (1, 5, and 15 min) in atmospheric air. A 200 nm oxide layer was generated on AA1050 after the...... 15 min air corona treatment. A significant reduction in anodic and cathodic reactivities was observed starting from 1 min exposure, which further decreased with prolonged exposure (15 min) and after delayed testing (after 30 days). The reduction in surface reactivity is due to the formation of...

  5. Radiation Induced Removal of Stacking Faults in Quenched Aluminium

    International Nuclear Information System (INIS)

    The effect of neutron irradiation on specimens of quenched aluminium containing Frank sessile dislocation loops has been studied by means of electron microscopy. The Frank loops were found to trans. form into perfect loops at doses less than 1017 nvt. A possible reason for the removal of the stacking faults is the displacement of a number of atoms at the faults, leading to the passage of a Shockley partial. Unfaulting induced by stress fields from dislocations, released during the irradiation, can also be important

  6. The influence of alloy composition on residual stresses in heat treated aluminium alloys

    Energy Technology Data Exchange (ETDEWEB)

    Robinson, J.S., E-mail: jeremy.robinson@ul.ie [Department of Mechanical, Aeronautical and Biomedical Engineering, University of Limerick (Ireland); Redington, W. [Materials and Surface Science Institute, University of Limerick (Ireland)

    2015-07-15

    The as quenched properties of eight different heat treatable aluminium alloys are related to residual stress magnitudes with the objective being to establish if there is a relationship between the residual stress and the as quenched alloy hardness and strength. Near surface residual stresses were assessed with X-ray diffraction using both the established sin{sup 2}ψ method and the more recent cos α technique. Through thickness residual stresses were also characterised using neutron diffraction. The alloys were chosen to encompass a wide range of strengths. The low to medium strength alloys were 6060 and 6082, medium to high strength 2618A, 2014A, 7075, 7010 and two variants of 7449, while the very high strength alloy was the powder metallurgy alloy N707. To assess the as quenched strength, dynamic hardness and tensile properties were determined from samples tested immediately after quenching to minimise the influence of precipitation hardening by natural aging. In addition, hot hardness measurements were made in situ on samples cooled to simulate quench paths. Within the experimental constraints of the investigation, the distribution of residual stress through the thickness was found to follow the same pattern for all the alloys investigated, varying from tensile in the interior to surface compression. The influence of alloy strength was manifested as a change in the observed residual stress magnitudes, and surface residual stresses were found to vary linearly with as quenched hardness and strength. - Highlights: • As quenched aluminium alloys contain high magnitude residual stresses. • Surface is compressive balance by a tensile core. • As quenched surface residual stress is linear function of alloy strength. • In situ hot hardness demonstrates rapid change in intrinsic hardness during rapid cooling.

  7. The influence of alloy composition on residual stresses in heat treated aluminium alloys

    International Nuclear Information System (INIS)

    The as quenched properties of eight different heat treatable aluminium alloys are related to residual stress magnitudes with the objective being to establish if there is a relationship between the residual stress and the as quenched alloy hardness and strength. Near surface residual stresses were assessed with X-ray diffraction using both the established sin2ψ method and the more recent cos α technique. Through thickness residual stresses were also characterised using neutron diffraction. The alloys were chosen to encompass a wide range of strengths. The low to medium strength alloys were 6060 and 6082, medium to high strength 2618A, 2014A, 7075, 7010 and two variants of 7449, while the very high strength alloy was the powder metallurgy alloy N707. To assess the as quenched strength, dynamic hardness and tensile properties were determined from samples tested immediately after quenching to minimise the influence of precipitation hardening by natural aging. In addition, hot hardness measurements were made in situ on samples cooled to simulate quench paths. Within the experimental constraints of the investigation, the distribution of residual stress through the thickness was found to follow the same pattern for all the alloys investigated, varying from tensile in the interior to surface compression. The influence of alloy strength was manifested as a change in the observed residual stress magnitudes, and surface residual stresses were found to vary linearly with as quenched hardness and strength. - Highlights: • As quenched aluminium alloys contain high magnitude residual stresses. • Surface is compressive balance by a tensile core. • As quenched surface residual stress is linear function of alloy strength. • In situ hot hardness demonstrates rapid change in intrinsic hardness during rapid cooling

  8. Gas-Phase Deposition of Ultrathin Aluminium Oxide Films on Nanoparticles at Ambient Conditions

    Directory of Open Access Journals (Sweden)

    David Valdesueiro

    2015-03-01

    Full Text Available We have deposited aluminium oxide films by atomic layer deposition on titanium oxide nanoparticles in a fluidized bed reactor at 27 ± 3 °C and atmospheric pressure. Working at room temperature allows coating heat-sensitive materials, while working at atmospheric pressure would simplify the scale-up of this process. We performed 4, 7 and 15 cycles by dosing a predefined amount of precursors, i.e., trimethyl aluminium and water. We obtained a growth per cycle of 0.14–0.15 nm determined by transmission electron microscopy (TEM, similar to atomic layer deposition (ALD experiments at a few millibars and ~180 °C. We also increased the amount of precursors dosed by a factor of 2, 4 and 6 compared to the base case, maintaining the same purging time. The growth per cycle (GPC increased, although not linearly, with the dosing time. In addition, we performed an experiment at 170 °C and 1 bar using the dosing times increased by factor 6, and obtained a growth per cycle of 0.16 nm. These results were verified with elemental analysis, which showed a good agreement with the results from TEM pictures. Thermal gravimetric analysis (TGA showed a negligible amount of unreacted molecules inside the alumina films. Overall, the dosage of the precursors is crucial to control precisely the growth of the alumina films at atmospheric pressure and room temperature. Dosing excess of precursor provokes a chemical vapour deposition type of growth due to the physisorption of molecules on the particles, but this can be avoided by working at high temperatures.

  9. Nouveau procédé de synthèse du nitrure d'aluminium

    OpenAIRE

    Haussonne, J.; Lostec, J.; Bertot, J.; Lostec, L.; Sadou, S.

    1993-01-01

    Les calculs thermodynamiques montrent que, même à température ambiante, l'aluminium pur peut réagir avec l'azote pour former le nitrure d'aluminium AlN. Cependant, la poudre d'aluminium pur n'existe pas : ses grains sont toujours entourés d'une couche d'alumine protectrice. De plus, dans l'hypothèse où l'on pourrait faire réagir de la poudre d'aluminium avec de l'azote, il se formerait de même une couche protectrice de nitrure d'aluminium qui empêcherait le centre des grains de réagir. S'insp...

  10. The influence of aluminium upon electronic transport in r.f. sputtered amorphous Si:H

    International Nuclear Information System (INIS)

    A range of specimens has been prepared in which aluminium is introduced into hydrogenated amorphous silicon by a co-sputtering technique. With increasing aluminium content, the activation energy of the dark d.c. conductivity and the optical energy gap are both found to decrease, whilst the magnitude of the d.c. conductivity is increased at all temperatures within the range of study. The inclusion of aluminium is found to quench the photoconductivity to a level below the resolution of the measurement system. Thermoelectric power measurements on films with a high aluminium content indicate that transport is dominated by holes. The data are interpreted in terms of the semiconducting properties of a silicon - aluminium alloy. High-temperature transport is dominated by holes in extended valence-band states, whilst at low temperatures carrier motion is through localized states situated between the Fermi level and the valence-band mobility edge. (author)

  11. Influence of aluminium upon electronic transport in RF sputtered amorphous Si:H

    Energy Technology Data Exchange (ETDEWEB)

    Fortuna, H.S.; Marshall, J.M.

    1986-05-01

    A range of specimens has been prepared in which aluminium is introduced into hydrogenated amorphous silicon by a co-sputtering technique. With increasing aluminium content, the activation energy of the dark d.c. conductivity and the optical energy gap are both found to decrease, whilst the magnitude of the d.c. conductivity is increased at all temperatures within the range of study. The inclusion of aluminium is found to quench the photoconductivity to a level below the resolution of the measurement system. Thermoelectric power measurements on films with a high aluminium content indicate that transport is dominated by holes. The data are interpreted in terms of the semiconducting properties of a silicon -aluminium alloy. High-temperature transport is dominated by holes in extended valence-band states, whilst at low temperatures carrier motion is through localized states situated between the Fermi level and the valence-band mobility edge.

  12. Low-temperature Electrodeposition of Aluminium from Lewis Acidic 1-Allyl-3-methylimidazolium Chloroaluminate Ionic Liquids

    Institute of Scientific and Technical Information of China (English)

    郑勇; 张锁江; 吕兴梅; 王倩; 左勇; 刘恋

    2012-01-01

    Lewis acidic 1-allyl-3-methylimidazolium chloroaluminate ionic liquids were used as promising electrolytes in the low-temperature electrodeposition of aluminium. Systematic studies on deposition process have been performed by cYClic voltammetry and chronoamperometry. The surface morphology and X-ray diffraction (XRD) patterns of deposits prepared at different experimental conditions were also investigated. It was shown that the nucleation density and growth rate of crystallites had a great effect on the structure of aluminium deposited. The crys- tallographic orientation of deposits was mainly influenced by temperature and current density. Smooth, dense and well adherent aluminium coatings were obtained on copper substrates at 10-25 mA.cm^-2 and 313.2-353.2 K. More- over, the current efficiency of deposition and purity of aluminium have been significantly improved, demonstrating that the ionic liquids tested have a prospectful potential in electroplating and electrorefining of aluminium.

  13. Production and some properties of Si3N4 reinforced aluminium alloy composites

    Directory of Open Access Journals (Sweden)

    Pardeep Sharma

    2015-09-01

    Full Text Available The present research work focuses on the production of aluminium (AA6082-T6 matrix composites reinforced with various weight percentage of silicon nitride particles by conventional stir casting route. The percentage of reinforcement is varied from 0 wt.% to 12 wt.% in a stage of 3%. The microstructures and mechanical properties of the fabricated aluminium matrix composites are investigated. The scanning electron microstructure images reveal the presence of Si3N4 particles in the aluminium matrix. The distribution of Si3N4 particles has also been recognized with X-ray diffraction technique. The mechanical properties such as ultimate tensile strength and hardness have improved at the cost of reduction in ductility with increase in weight percentage of silicon nitride particulates in the aluminium metal matrix. The density and porosity of the composites also show an increasing trend with increase in volume fraction of Si3N4 particles in the aluminium matrix.

  14. Electrodeposition of gallium and zinc onto aluminium. Influence of the electrodeposited metals on the activation process

    International Nuclear Information System (INIS)

    The electrodeposition of gallium and/or zinc on aluminium, aluminium-zinc alloy and vitreous carbon electrodes in chloride solutions is analysed. The electrodissolution of the formed interfaces is also described and discussed. For this purpose, potentiodynamic and potentiostatic techniques and open circuit potential measurements were employed and surface characterisation was performed by scanning electron microscopy and energy dispersive X-ray analysis. The presence of zinc, electrodeposited from the solution or as an alloying component, facilitates gallium enrichment at the interface and improves the wetting on the aluminium oxide. These conditions ensure the formation of a surface Ga-Al amalgam. As a result, the dissolution process occurs at potentials which are more active than those observed for aluminium or aluminium-zinc alloy in halide solutions

  15. Precipitation behaviour and recrystallisation resistance in aluminum alloys with additions of hafnium, scandium and zirconium

    OpenAIRE

    Hallem, Håkon

    2005-01-01

    The overall objective of this work has been to develop aluminium alloys, which after hot and cold deformation are able to withstand high temperatures without recrystallising. This has been done by investigating aluminium alloys with various additions of hafnium, scandium and zirconium, with a main focus on Hf and to which extent it may partly substitute or replace Zr and/or Sc as a dispersoid forming elements in these alloys.What is the effect of hafnium, alone and in combination with Zr and/...

  16. Gas accumulation at grain boundaries during 800 MeV proton irradiation of aluminium and aluminium-alloys

    DEFF Research Database (Denmark)

    Singh, Bachu Narain; Horsewell, Andy; Sommer, W. F.;

    1986-01-01

    Samples of pure aluminium (99.9999%) and commercial Al-2.7%Mg(AlMg3) and Al-1.1%Mg-0.5%Si(Al6061) alloys were irradiated with 800 MeV protons at the Los Alamos Meson Physics Facility (LAMPF) at a temperature between 40-100°C to a maximum dose of 0.2 dpa. Transmission electron microscopy (TEM) sho...... higher than in the pure Al. The amount of gas accumulation at grain boundaries was found to depend on gas generation rate, alloying and cold-work microstructure...

  17. Schiff bases as corrosion inhibitor for aluminium in HCl solution

    International Nuclear Information System (INIS)

    Highlights: ► Three Schiff bases have been tested as possible corrosion inhibitors for aluminium. ► Corrosion tests have been performed via EIS and Tafel polarisation methods. ► Experimental inhibition efficiencies were correlated with quantum chemical parameters. - Abstract: Three Schiff bases named 1,5-bis[2-(2-hydroxybenzylideneamino)phenoxy]-3-oxopentane (D1), 1,5-bis[2-(5-chloro-2-hydroxybenzylideneamino)phenoxy]-3-oxopentane (D2) and 1,5-bis[2-(5-bromo-2-hydroxybenzylideneamino)phenoxy]-3-oxopentane (D3) were synthesized and their inhibitive capabilities on the aluminium corrosion in 0.1 M HCl were investigated by means of electrochemical impedance spectroscopy, Tafel polarisation and scanning electron microscopy techniques. Results showed that, compounds under study exhibit inhibitor properties and adsorption of these compounds was found to accord with Temkin adsorption isotherm. Polarisation curves indicated that the studied Schiff bases were cathodic inhibitor and the effectiveness of these inhibitors decreased in the order of D3 > D2 > D1. Quantum chemical calculations were performed to provide further insight into the inhibition efficiencies determined experimentally.

  18. Experimental study of friction in aluminium bolted joints

    Science.gov (United States)

    Croccolo, D.; de Agostinis, M.; Vincenzi, N.

    2010-06-01

    This study aims at developing an experimental tool useful to define accurately the friction coefficients in bolted joints and, therefore, at relating precisely the tightening torque to the bolt preloading force in some special components used in front motorbike suspensions. The components under investigation are some clamped joints made of aluminium alloy. The preloading force is achieved by applying a torque wrench to the bolt head. Some specific specimens have been appropriately designed and realized in order to study the tribological aspects of the tightening phase. Experimental tests have been performed by applying the Design of Experiment (DOE) method in order to obtain a mathematical model for the friction coefficients. Three replicas of a full factorial DOE at two levels for each variable have been carried out. The levels include cast versus forged aluminium alloy, anodized versus spray-painted surface, lubricated versus unlubricated screw, and first tightening (fresh unspoiled surfaces) versus sixth tightening (spoiled surfaces). The study considers M8x1.25 8.8 galvanized screws.

  19. Experimental study of aluminium honeycomb behaviour under dynamic multiaxial loading

    Directory of Open Access Journals (Sweden)

    Markiewicz E.

    2012-08-01

    Full Text Available Split Hopkinson Pressure Bar system (SHPB with large-diameter and Nylon bars introducing a shear-compression loading device is used in order to investigate the dynamic behaviour of aluminium honeycomb under multiaxial loadings conditions. All shear-compression configurations including the loading angle variation from 0∘ to 60∘ are performed with an impact velocity of about 15m/s. The adapted SHPB system with the device are validated numerically and a phenomenon of separation between the input bar and the input beveled bar is observed. Numerical results suggest that this phenomenon provides a cutting of the reflected wave. An electro optical extensometer is employed in experiments. A good agreement between the numerical elastic waves and the experimental ones is obtained. Experimental results show a significant effect of the loading angle on the apparent stress-strain curves. The initial peak value and the plateau stress decrease with the increase of the loading angle. The combined shear-compression device with an enhancement at the alignment set-up provides efficient results for samples dynamically loaded. This device will be used to investigate the influence of the in-plane orientation angle on the deformation mechanisms and multiaxial behaviour of aluminium honeycomb under dynamic and quasi-static loading conditions.

  20. High-Rate Compaction of Aluminium Alloy Foams

    International Nuclear Information System (INIS)

    The response of aluminium foams to impact can be categorised according to the impact velocity. Tests have been carried out at a range of impact velocities from quasi-static to velocities approaching the speed of sound in the foam. Various experimental arrangements have been employed including pneumatic launcher tests and plate impact experimants at velocities greater than 1000 m s-1. The quasi-static compression behaviour was approximately elastic, perfectly-plastic, locking. For static and dynamic compression at low impact velocities the deformation pattern was through the cumulative multiplication of discrete, non-contiguous crush bands. Selected impact tests are presented here for which the impact velocity is less than the velocity of sound, but above a certain critical impact velocity so that the plastic compression occurs in a shock-like manner and the specimens deform by progressive cell crushing. Laboratory X-ray microtomography has been employed to acquire tomographic datasets of aluminium foams before and after tests. The morphology of the underformed foam was used as the input dataset to an Eulerian code. Hydrocode simulations were then carried out on a real microstructure. These simulations provide insight to mechanisms associated with the localization of deformation

  1. Graded open-cell aluminium foam core sandwich beams

    International Nuclear Information System (INIS)

    We show that the replication process can be extended towards the production of functionally graded porous structures by fabricating and testing structures in which outer layers of dense metal encase a central part made of foam with graded porosity. Samples of this kind are produced by pressing individual layers of NaCl powder of granulometry 60-90 μm, and then stacking these layers between two skins of dense aluminium. The stacked preforms are then infiltrated with pure aluminium and solidified before dissolution of the salt in water. Specimens containing up to five layers of porous Al of different density between two dense outer skins of pure Al are produced; selected samples are tested in three-point bending. Data show good agreement with analysis based on sandwich beam theory and the Deshpande-Fleck yield criterion. Results of this work indicate that whereas lightweight graded metal/metal foam beams show little promise from the standpoint of stiffness-limited design, they may be of interest from the standpoint of load-limited design

  2. A 3D printed superconducting aluminium microwave cavity

    Science.gov (United States)

    Creedon, Daniel L.; Goryachev, Maxim; Kostylev, Nikita; Sercombe, Timothy B.; Tobar, Michael E.

    2016-07-01

    3D printing of plastics, ceramics, and metals has existed for several decades and has revolutionized many areas of manufacturing and science. Printing of metals, in particular, has found a number of applications in fields as diverse as customized medical implants, jet engine bearings, and rapid prototyping in the automotive industry. Although many techniques are used for 3D printing metals, they commonly rely on computer controlled melting or sintering of a metal alloy powder using a laser or electron beam. The mechanical properties of parts produced in such a way have been well studied, but little attention has been paid to their electrical properties. Here we show that a microwave cavity (resonant frequencies 9.9 and 11.2 GHz) 3D printed using an Al-12Si alloy exhibits superconductivity when cooled below the critical temperature of aluminium (1.2 K), with a performance comparable with the common 6061 alloy of aluminium. Superconducting cavities find application in numerous areas of physics, from particle accelerators to cavity quantum electrodynamics experiments. The result is achieved even with a very large concentration of non-superconducting silicon in the alloy of 12.18%, compared with Al-6061, which has between 0.4% and 0.8%. Our results may pave the way for the possibility of 3D printing superconducting cavity configurations that are otherwise impossible to machine.

  3. Experimental study of friction in aluminium bolted joints

    Directory of Open Access Journals (Sweden)

    Vincenzi N.

    2010-06-01

    Full Text Available This study aims at developing an experimental tool useful to define accurately the friction coefficients in bolted joints and, therefore, at relating precisely the tightening torque to the bolt preloading force in some special components used in front motorbike suspensions. The components under investigation are some clamped joints made of aluminium alloy. The preloading force is achieved by applying a torque wrench to the bolt head. Some specific specimens have been appropriately designed and realized in order to study the tribological aspects of the tightening phase. Experimental tests have been performed by applying the Design of Experiment (DOE method in order to obtain a mathematical model for the friction coefficients. Three replicas of a full factorial DOE at two levels for each variable have been carried out. The levels include cast versus forged aluminium alloy, anodized versus spray-painted surface, lubricated versus unlubricated screw, and first tightening (fresh unspoiled surfaces versus sixth tightening (spoiled surfaces. The study considers M8x1.25 8.8 galvanized screws.

  4. Modelling of semi-liquid aluminium flow in extrusion

    Directory of Open Access Journals (Sweden)

    G. Skorulski

    2007-04-01

    Full Text Available characterizing by low cost. The significant results may be quickly applying using theory of probability. The way of modelling the deformation mechanisms during extrusion of aluminium alloys in semi - liquid phase, the way of preparing samples and experimental technique has been analysed in the following work. On the ground of received results (i.e. registrations of consecutive process steps the grid of the flow velocity vectors on a flat sample surface was done. It allowed to draw conclusions which one of the basic deformation mechanisms is dominant in particular stage of the process. The technique of measurement has been shown as well. Experiments are made using plasticine and rape oil as a substiute materials. Some kind of different variants have been investigated. To ensure that such model experiments provide useful information it is essential to select model materials and prepare samples that would exhibit (preferably at room temperature similar behaviour and similar deformation mechanisms as those present during the actual deformation process of aluminium alloys in a semi-liquid state. In particular the FLS, SS and PDS mechanisms should be adequately reproduced.

  5. Aluminium surface treatment with ceramic phases using diode laser

    Science.gov (United States)

    Labisz, K.; Tański, T.; Brytan, Z.; Pakieła, W.; Wiśniowski, M.

    2016-07-01

    Ceramic particles powder feeding into surface layer of engineering metal alloy is a well-known and widely used technique. New approach into the topic is to obtain finely distributed nano-sized particles involved in the aluminium matrix using the traditional laser technology. In this paper are presented results of microstructure investigation of cast aluminium-silicon-copper alloys surface layer after heat treatment and alloying with ceramic carbides of WC and ZrO2 using high-power diode laser. The surface layer was specially prepared for the reason of reducing the reflectivity, which is the main problem in the up-to-date metal matrix composites production. With scanning electron microscopy, it was possible to determine the deformation process and distribution of WC and ZrO2 ceramic powder phase. Structure of the surface after laser treatment changes, revealing three zones—remelting zone, heat-affected zone and transition zone placed over the Al substrate. The structural changes of ceramic powder, its distribution and morphology as well as microstructure of the matrix material influence on functional properties, especially wear resistance and hardness of the achieved layer, were investigated.

  6. A 3D Printed Superconducting Aluminium Microwave Cavity

    CERN Document Server

    Creedon, Daniel L; Kostylev, Nikita; Sercombe, Tim; Tobar, Michael E

    2016-01-01

    3D printing of plastics, ceramics, and metals has existed for several decades and has revolutionized many areas of manufacturing and science. Printing of metals in particular has found a number of novel applications in fields as diverse as customized medical implants, jet engine bearings, and rapid prototyping in the automotive industry. Whilst many techniques can be used for 3D printing metals, they commonly rely on computer controlled melting or sintering of a metal alloy powder using a laser or electron beam. The mechanical properties of parts produced in such a way have been well studied, but little attention has been paid to their electrical properties. Here we show that a resonant microwave cavity 3D printed using an Al-12Si alloy exhibits superconductivity when cooled below the critical temperature of aluminium (1.2 K), with a performance comparable to the common 6061 alloy of aluminium. Superconducting cavities find application in numerous areas of physics, from particle accelerators to cavity quantum...

  7. The determination of boron in aluminium of high purity

    International Nuclear Information System (INIS)

    A description is given of the investigations that led to the development of chemical methods for the determination of boron within the range 0,25 to 1,0 p.p.m. in aluminium of high purity. Methods were developed that incorporated fluorimetry, directly in solutions containing aluminium and after separation of boron by liquid-liquid extraction into 2-ethyl-1,3 hexanediol. A published spectrophotometric method, involving extraction of the BF4sup(-) complex with methylene blue into dichloroethane, was modified for application to alluminium samples. Details of this modified procedure and the fluorimetric-extraction procedure are appended. The precision of the methylene-blue method is about 6 percent relative and is recommended for precision and speed in preference to others. Separation of boron by distillation and spectrophotometric determination with curcumin gave low values in comparison with those obtained by the other methods. Agreement between the boron values obtained on the samples tested was good for the fluorimetric and methylene-blue spectrophotometric methods

  8. An investigation of coated aluminium bipolar plates for PEMFC

    International Nuclear Information System (INIS)

    Highlights: ► Coated aluminium bipolar plates demonstrate the hydrophobic property than the raw material. ► The corrosion behaviour of bipolar plate decreases the PEMFC performance severely. ► These PEMFCs are measured by current–voltage (I–V) curve test. ► The oxide film increases the interfacial contact resistance. -- Abstract: The performance of Al-alloy bipolar plates for the PEMFC (proton exchange membrane fuel cell) system is investigated in this paper. The metallic bipolar plates are modified with a Ni–P coating. The performance of the Al-alloy bipolar plates is evaluated by the coating structure, corrosion resistance, contact angle and single cell performance. The results indicate that the coated aluminium bipolar plates demonstrate hydrophobic and anti-corrosive properties. The hydrophobic property increases the contact angle on the surface from 46.08° to 80.51°. Meanwhile, the corrosion rate of the Ni–P coating can be over 1 order of magnitude lower than that of the substrate. Hence, the substrate with the coating maintains superior performance under the long term test. The present study proves that both the hydrophobicity and corrosion resistance significantly affect the metallic bipolar plate.

  9. Crystallographic orientation-spray formed hypereutectic aluminium-silicon alloys

    Directory of Open Access Journals (Sweden)

    Hamilta de Oliveira Santos

    2005-06-01

    Full Text Available Aluminium-silicon alloys have been wide accepted in the automotive, electric and aerospace industries. Preferred orientation is a very common condition for metals and alloys. Particularly, aluminium induces texture during the forming process. The preparation of an aggregate with completely random crystal orientation is a difficult task. The present work was undertaken to analyse the texture by X-ray diffraction techniques, of three spray formed hypereutectic Al-Si alloys. Samples were taken from a billet of an experimental alloy (alloy 1 and were subsequently hot-rolled and cold-rolled (height reduction, 72% and 70%, respectively. The other used samples, alloys 2 and 3, were taken from cylinders liners. The results from the Laue camera showed texture just in the axial direction of alloy 3. The pole figures also indicated the presence of a typical low intensity deformation texture, especially for alloy 3. The spray formed microstructure, which is very fine, hinders the Al-Si texture formation during mechanical work.

  10. Synergistic Effect of Azadirachta Indica Extract and Iodide Ions on the Corrosion Inhibition of Aluminium in Acid Media

    International Nuclear Information System (INIS)

    The synergistic action caused by iodide ions on the corrosion inhibition of aluminium (Al) in 0.5 M HCl in the presence of Azadirachta Indica (AZI) plant extract has been investigated using potintiodynamic polarization and impedance techniques. It is found that AZI extract inhibits the corrosion of aluminium in 0.5 M HCl. The inhibition efficiency increases with the increase in AZI extract concentration, until 24% v/v of AZI extract, then Inh.% is decreased with father increase in AZI extract concentration. The adsorption of this extract in the studied concentration is found to obey Frewendlish adsorption isotherm. The addition of iodide ions enhances the inhibition efficiency to a considerable extent. The increase in Inh.% values in presence of fixed concentration of iodide ions indicates that AZI extract forms an insoluble complex at lower AZI extract concentrations by undergoing a joint adsorption. But at higher concentrations of AZI extract, competitive adsorption is found between iodide ions and the formed complex leading to less Inh.%. The Inh.% decreased in presence of iodide ions with AZI extract than in presence of AZI extract alone at all studied iodide concentrations. The synergism parameter S θ is defined and calculated from surface coverage values. This parameter in the case of AZI extract is found to be more than unity, indicating that the enhanced inhibition efficiency caused by the addition of iodide ions

  11. Studies of the subsurface zone created in aluminium and its alloys by means of positron annihilation and complementary methods

    International Nuclear Information System (INIS)

    There are presented the results of the studies of the subsurface zone created in aluminium and its alloys during sliding or other surface modification treatments. The application of the positron annihilation techniques due to their high sensitivity to crystal lattice defects enabled to determine defects profiles in the subsurface zone. The positron annihilation studies were correlated with other conventional measurements applied in tribology, i.e. microhardness measurements, scanning electron microscopy, X-ray diffraction and in a special case stress distribution calculated theoretically. It was shown that the positron annihilation spectroscopy is a useful tool for profiling of the subsurface zone created during sliding even for light metals their alloys and composites. The total range of the subsurface zone detected by the positron annihilation extends from 50 μm to 450 μm depending on the material studied and surface modification treatment. Additionally, the type of the main defects can be determined. The studies of the pure aluminium samples after dry sliding enabled to find the defect concentration of vacancy type in the depth less then 1 μm and to correlate its value with the size of crystallites. It supports the conclusion on recovery processes taking place in this layer. There was made the attempt to apply the Doppler broadening coincidence spectroscopy to the studies of aluminium alloy and composite. In view of the interdisciplinary character the present thesis enclose also the review of the basic issues of tribology, measurement methods applied to the subsurface zone studies and positron annihilation experimental techniques. (author)

  12. Relation between microstructure and thermal conductivity in aluminium nitride substrates; Relations entre la microstructure et la conductivite thermique dans les substrats de nitrure d`aluminium

    Energy Technology Data Exchange (ETDEWEB)

    Jarrige, J.; Lecompte, J.P.; Seck, O. [Faculte des Sciences (CNRS), 87 - Limoges (France). Laboratoire de Materiaux Ceramiques et Traitements de Surface

    1996-12-31

    Sintered aluminium nitride is a promising ceramic substrate for future power electronics applications. This ceramic is characterized by a high thermal conductivity (100 to 200 W/m.K) which depends on two main factors: the oxygen content of the AlN powder used for the sintering process and the microstructure of the sintered material. The oxygen content changes with sintering additions. For instance, boron nitride allows the diffusion of oxygen from the nitride grains to the grain joints. With a complement of yttrium oxide in the liquid phase, the BN/Y{sub 2}O{sub 3} couple allows to increase the conductivity to 190 W/m.K with a reduction of the oxygen content. The second part of the study concerns the microstructure of sintered materials. A control of conductivity can be obtained using an adjustment of the sintering cycles. Only two types of microstructure, the secondary phase dispersed in the AlN matrix and the secondary phase that concentrates around triple junctions, allow a better contact between nitride grains and thus higher conductivities of 210 W/m.K. (J.S.) 6 refs.

  13. Determination of local material properties of laser beam welded aluminium-steel and aluminium-titanium compounds

    Energy Technology Data Exchange (ETDEWEB)

    Hunkel, M.; Hehl, A. von [IWT Stiftung Institut fuer Werkstofftechnik Bremen (Germany); Barr, A.

    2012-04-15

    The combination of different metallic materials, such as aluminium and steel or aluminium and titanium, by firmly bonding via laser beam welding enables the production of customised hybrid lightweight designs with enhanced properties. Both weld geometry and local material behaviour, which are responsible for the final load characteristics of the compound, are influenced by the process parameters during welding. A novel approach of coupling process, microstructure and mechanical simulation, considering the development of weld geometry and local material conditions is intended to deliver a fast and reliable method for evaluating the quasi-static strength of laser beam welded hybrid compounds. Besides the objective to promote a reduction of expensive welding experiments, the developed method can enhance the performance of hybrid structures as well as their lightweight potential for automotive and aircraft applications. The experimental determination of the local mechanical properties as the basis for the regarded simulation approach is an essential part of a running research project. (Copyright copyright 2012 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)

  14. Nouveau procédé de synthèse du nitrure d'aluminium

    Science.gov (United States)

    Haussonne, J. M.; Lostec, J.; Bertot, J. P.; Lostec, L.; Sadou, S.

    1993-04-01

    Thermodynamic considerations show that, even at room temperature, pure aluminium can react with nitrogen to form the aluminium nitride AlN. However, pure aluminium does not exist: it is always surrounded by an alumina shell that protects the metal from further reactions. Furthermore, in the hypothesis where one has been able to make aluminium react with nitrogen, an aluminium nitride shell will protect as well the metal core from further oxidation. Prompted by the Lanxide process allowing to form Al/Al2O3 composites, we have mixed aluminium powders with lithium salts, and easily synthesized pure aluminium nitride by heating the mixed powders in nitrogen at temperatures ranging from 800 to 1200 °C. Starting from aluminium powders with a specific area ranging from 0.3 to 4 m^2/g, we have been able to produce aluminium nitride with specific are ranging from 1 to 20 m^2/g. Mixed with Y203-CaO and sintered at 1720 °C in N2, we obtained AIN ceramics owning 92% density and 160 W/m.K thermal conductivity. Les calculs thermodynamiques montrent que, même à température ambiante, l'aluminium pur peut réagir avec l'azote pour former le nitrure d'aluminium AlN. Cependant, la poudre d'aluminium pur n'existe pas : ses grains sont toujours entourés d'une couche d'alumine protectrice. De plus, dans l'hypothèse où l'on pourrait faire réagir de la poudre d'aluminium avec de l'azote, il se formerait de même une couche protectrice de nitrure d'aluminium qui empêcherait le centre des grains de réagir. S'inspirant du “procédé Lanxide” permettant de réaliser des composites Al/Al2O3, nous avons mélangé de la poudre d'aluminium avec des sels de lithium, et synthétisé du nitrure d'aluminium pur en portant ce mélange dans l'azote à une température pouvant être comprise entre 800 et 1 200 °C. Utilisant des poudres d'aluminium possédant une surface spécifique comprise entre 0,3 et 4 m^2/g, nous avons obtenu une poudre de nitrure d'aluminium avec une surface sp

  15. Innovative mechanical design: Foamed aluminium for automotive applications; Innovative Bauweisen: Aluminiumschaum fuer den Fahrzeugbau

    Energy Technology Data Exchange (ETDEWEB)

    Banhart, J.; Baumeister, J.; Melzer, A.; Weber, M. [Fraunhofer-Institut fuer Angewandte Materialforschung (Germany); Seeliger, W. [Karmann (W.) GmbH, Osnabrueck (Germany)

    1998-12-01

    Foamed metals as a material for innovative applications in the motor vehicle industry have been tested and evaluated over the last few years by industrial establishments and research institutes. Particularly composite materials - consisting of foamed aluminium and conventional shaped parts or sheets made of steel or aluminium - promise interesting applications. The paper discusses the technology for producing such composites. The basis is a method for preparing foamed aluminium from powdered source materials. Metal powders are blended with foaming agents and pressed to form a compact pre-product, subsequent heat treatment resulting in the foamed metal. An example is given illustrating the advantages of the foamed aluminium-aluminium sandwich material for automotive applications.(orig./CB) [Deutsch] Metallschaum als Werkstoff fuer innovative Anwendungen im Fahrzeugbau wurde in den letzten Jahren von Industrie und Forschungsinstituten intensiv evaluiert. Besonders Verbundloesungen - bestehend aus Aluminiumschaum und konventionellen Profilen oder Blechen aus Stahl oder Aluminium - versprechen hier interessante Anwendungsfelder. Die Moeglichkeiten zur Herstellung solcher Verbunde werden diskutiert. Als Grundlage dient ein Verfahren zur Herstellung von Aluminiumschaum auf Basis von pulverfoermigen Ausgangsmaterialien. Hierbei werden Metallpulver mit Treibmitteln gemischt, zu einem kompakten Vorprodukt verpresst und anschliessend in einem Waermebehandlungsprozess aufgeschaeumt. Als Beispiel fuer den Einsatz eines Aluminiumschaum-Aluminium-Sandwiches wird ein Teil vorgestellt, das die aus konventionellem Stahlblech gefertigte Rueckwand im Fahrzeug ersetzen soll und dabei bei reduziertem Gewicht eine erheblich hoehere Steifigkeit aufweist. (orig.)

  16. The Role Of Melatonin In Aluminium Induced Genotoxicity In Female Albino Rats

    Directory of Open Access Journals (Sweden)

    Zeinab E. Hanafy

    2007-09-01

    Full Text Available Aim of the work, In spite of the wide range of use of aluminium. With the increasing awareness of possible health hazards associated with their use, more attention have been focused on their biological and biochemical activity. Aluminium salts are used as the active antiperspirant in under cosmetics, but the effects of widespread, long term and increasing use remain unknown. Aluminium is known to have genotoxic profile, capable of causing both DNA alterations and epigenetic effects. Melatonin reduces the free radical generation and metal detoxification .This study was planned to determine the effects of melatonin on aluminium induced toxicity in the chromosomes of bone marrow cell . Material and Methods ,Forty female albino rats were used in the present work for the chromosomal analysis. Four groups of adult female albino rats were used in the following way: Group -I, control group; Group-II,50 mg /kg b.wt aluminium orally; Group-III, 50g / kg b.wt melatonin orally and Group- IV, 50 mg /kg b.wt aluminium orally (am +50 g / kg b.wt melatonin orally(pm. Doses were given 30 days. All animals were sacrificed and the bone marrow of femur bones was taken for subsequent cytogenetic studies. The results, Aluminium treatment induced a significant increase in the structural as well as numerical chromosomal aberrations . The frequency of chromosomal aberrations showed significant decrease when rats treated with melatonin and aluminium .In conclusion, the results indicated that melatonin showed a significant improvement of genetic damages induced by aluminium

  17. Effect of Fiber Surface Structure on Interfacial Reaction between Carbon Fiber and Aluminium

    Science.gov (United States)

    Chang, Kuang-Chih; Matsugi, Kazuhiro; Sasaki, Gen; Yanagisawa, Osamu

    Surface structure of carbon fiber and interfacial reaction between fiber and aluminium in carbon fiber reinforced aluminium composites were investigated by high-resolution transmission electron microscopy. Low and high graphitized carbon fiber reinforced pure aluminium composites were prepared by ultrasonic liquid infiltration. Vapor grown carbon nano fiber (VGCF) reinforced pure aluminium composites were prepared by hot-pressing. Heteroatoms, which existed abundantly in the surface of low graphitized carbon fiber, caused carbon lamellar structure in the fiber surface pronounced curvature. VGCF surface structure appeared regular and linear graphitic lamellae. Low graphitized fiber reinforced pure aluminium composites revealed serious interfacial reaction produced crystalline aluminium carbides (Al4C3), compared to composites reinforced by high graphitized fiber. On the other hand, Al4C3 crystalline reactants were not found at the interface of VGCF reinforced pure aluminium composites, but formation of interlayer was observed. In order to promote Al4C3 growth, carbon fiber reinforced composites were heat-treated at 573K and 873K for 1.8ks. Al4C3 interfacial phases in low and high graphitized fiber reinforced aluminium composites grew with the rise in the temperature. The heat-treatment resulted in the formation of non-crystalline Al4C3 interlayer by energy dispersive X-ray spectroscopy analysis of electron microscopy. At high temperature, Al4C3 was not grew and increased merely at the interface between carbon fiber and pure aluminium matrix, and moreover, the formation of new Al4C3 crystal occurred in this interlayer.

  18. Behaviour of painted aluminium in Ibero-American atmospheres

    Directory of Open Access Journals (Sweden)

    Morcillo, M.

    2003-12-01

    Full Text Available Aluminium generally presents good corrosion resistance to the atmosphere. However, unprotected aluminium and aluminium alloys weather outdoors to an ugly grey colour, which deepens to black in industrial atmospheres, and undergo superficial pitting in marine atmospheres, etc. Finishing technologies are applied for their protection and decoration in a wide range of applications. These technologies basically consist of two protection processes: anodizing and painting; the latter going from conventional solvent base paints to modem water-borne, high solids and powder coatings. This paper considers the weathering performance of three paint systems: alkyd, polyurethane and polyester, after more than three years of exposure in a wide spectra of Ibero-American atmospheric conditions. The information reported includes resistance to undercutting corrosion at the scribe, filiform corrosion, fungal attack and change in the physical-chemical properties of the paint surface (loss of gloss, colour changes, chalking, etc..

    El aluminio, en general, presenta una buena resistencia a la corrosión en la atmósfera. Sin embargo, el aluminio sin ninguna protección y las aleaciones de aluminio expuestas a la intemperie envejecen mostrando un color gris, negro en el caso de atmósferas industriales, sufren la formación de picaduras en atmósferas marinas, etc. Para su protección, o a efectos decorativos, se le aplican diferentes procesos de acabado en un amplio rango de aplicaciones. Estos procesos de acabado, básicamente consisten en dos métodos de protección: anodizado y pintado; este último abarca desde pinturas convencionales de base disolvente hasta modernos sistemas base agua, de alto contenido en sólidos o pinturas en polvo. Este trabajo considera el comportamiento de tres sistemas de pinturas: alquídico, poliuretano y poliéster, tras más de tres años de exposición en un amplio espectro de condiciones atmosféricas de Iberoamérica. La

  19. Influence of Aluminium on Performance of HTPB-based Aluminised PBXs

    Directory of Open Access Journals (Sweden)

    Vinay Prakash

    2004-10-01

    Full Text Available The paper describes the development of aluminised plastic-bonded explosives (PBXs based on aluminium and nitramine explosives using hydroxy-terminated polybutadiene as polymer matrix. The PBXs were processed as per standard procedures. Compositions with different formulations were prepared by varying the percentages of aluminium and RDX and their explosive properties, including velocity of detonation (VOD, peak overpressure, duration, impulse and sensitivity to different types of stimuli, were studied. The experimental and theoretical values of the VOD have been compared. It is observed that about 15 per cent aluminium content in the aluminised PBXs shows the optimum VOD.

  20. Car-Parrinello Simulation of the Aluminium Oxidation: Questioning the Role of 'Hot Adatoms'

    CERN Document Server

    Schulte, Marius

    2012-01-01

    We present Car-Parrinello molecular dynamics simulations of the initial reaction steps leading to an inert oxide layer on aluminium. The mechanism of the reaction of the aluminium surface with single oxygen molecules is analysed. After adsorption at the surface the oxygen molecules dissociate at a femtosecond timescale and the atoms are chemisorbed at the surface at a distance of several angstrom which falsifies earlier STM results. When the aluminium surface is exposed to higher oxygen pressure, a surface layer essentially consisting of threefold coordinated oxygen atoms starts to form.