WorldWideScience

Sample records for aluminium foundry alloys

  1. Assessment of air pollutants produced by industrial activity from an aluminium alloys foundry

    Directory of Open Access Journals (Sweden)

    D. Cirtina

    2015-10-01

    Full Text Available The industrial activity in non-ferrous alloys foundries leads to the elimination of the pollutants in the atmosphere that may have adverse effects on the environment and human health. This paper presents an evaluation of the pollutantemissions resulting from an aluminium foundry starting from data on concentrations and pollutant massflow rates estimated for each phase of the technological process and on measured ambient levels for the area of influence of the objective to study.

  2. Mushy Zone Properties and Castability of Aluminium Foundry Alloys

    Energy Technology Data Exchange (ETDEWEB)

    Dahle, A.K.

    1996-01-01

    The growing application and market share of aluminium castings demand better understanding of the mechanisms of defect formation during casting. Although casting is a cost-effective production route, inadequate reproducibility and quality of the cast structure often restrict the utilization of castings. This doctoral thesis aims to (1) determine how the solidification conditions affect the rheological behaviour in the partially solidified state, (2) to measure how alterations in solidification variables influence castability, and (3) to investigate the relationship between mushy zone rheology and castability. The development of mechanical strength in the mushy zone was measured as a function of chemical composition. Measurements of the dendrite coherency point provided accurate determination of the point where the dendrite network is established. The strength measurements confirm that the dendrites are largely independent and free-floating before dendrite coherency. The point and rate of strength development in the subsequently established interdendritic network strongly depend on the size and morphology of the dendrites and fraction solid. The castability investigation was limited to evaluations of fluidity and feeding. Fluidity measurements showed a complex effect of increased grain refinement. Alterations of the concentration and type of main alloying element gave a direct relationship between mushy zone rheology and fluidity. The range of the operating feeding mechanisms during solidification is directly related to the rheological properties of the mushy zone. 251 refs., 77 refs., 25 tabs.

  3. Foundry Technology of GIS Aluminium Alloy Tank%GIS铝合金罐体的铸造技术

    Institute of Scientific and Technical Information of China (English)

    丁苏沛; 康敬乐; 史学谦; 毕建峰; 郭小花

    2011-01-01

    The involved equipment, die and mold as well as technological essentials for casting of aluminium alloy tank with foundry method such as sand casting, low pressure sand casting, low pressure permanent die casting with sand core, low pressure permanent die casting and Vacuum sealed molding process have been analysed and discussed.%本文就铝合金罐体的主要铸造方法(即砂型铸造、砂型低压铸造、金属型砂芯低压铸造、金属型低压铸造和V法铸造)所涉及的设备、模具和工艺方面的技术要点进行分析和探讨.

  4. SURFACE MELTING OF ALUMINIUM ALLOYS

    OpenAIRE

    Veit, S.; Albert, D; Mergen, R.

    1987-01-01

    The wear properties of aluminium base alloys are relatively poor. Laser surface melting and alloying has proved successful in many alloy systems as a means of significantly improving the surface properties. The present work describes experiments designed to establish the scope of laser treatment of aluminium alloys. Aluminium does not absorb CO2 laser light as well as other metals which necessitated first a general study of absorption caotings. Aluminium alloys offer fewer opportunities than ...

  5. Aluminium and iron air pollution near an iron casting and aluminium foundry in Turin district (Italy).

    Science.gov (United States)

    Polizzi, Salvatore; Ferrara, Mauro; Bugiani, Massimiliano; Barbero, Domenico; Baccolo, Tiziana

    2007-09-01

    This work reports the results of an environmental survey carried out in an industrial area in the Province of Turin: its main aim is to assess the levels of iron and aluminium in the outside air during the period from July to September to assess the influence of industrial activity (a cast-iron and aluminium foundry) which is interrupted during the month of August, on the level of metals present in the air. Conducting the analysis during this period of time made it possible to avoid the confounding effect of pollution due to domestic central heating. The measurements were taken from nine areas at different distances from the foundry in the area and according to the direction of the prevailing winds, as deduced from the historical data. The results of this survey show a statistically significant difference in iron and aluminium levels in the outside air in the geographic areas between the two main periods examined: during August (no foundry activity) v/s July-September (foundry activity). The values recorded are: Aluminium 0.4+/-0.45 microg/m(3) v/s 1.12+/-1.29 microg/m(3) (pIron 0.95+/-0.56 microg/m(3) v/s 1.6+/-1.0 microg/m(3) (piron tended to be higher in the areas farther away from the foundry site in the areas located along the path of the prevailing winds.

  6. Mechanism of Nickel-Aluminium Alloy Electroplating

    Institute of Scientific and Technical Information of China (English)

    2003-01-01

    The effect of operating conditions on the aluminium content of Ni-Al alloy deposit and the catalytic function of NaF on electrodeposition in the nonaqueous solution containing aluminium are investigated.The results indicate that the plated aluminuim content will be increased with the rise of current density in a given range.When the current density is 2.5A/dm2,nickle-aluminium alloy containing 13.1 wt% aluminium will be deposited.The plated aluminium content will be increased by 2wt% as 0.1mol/L NaF is added to the bath.

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

    DEFF Research Database (Denmark)

    Ambat, Rajan; Dwarakadasa, E.S.

    1996-01-01

    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...

  8. 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...

  9. Long - range foundry Al composite alloys

    Directory of Open Access Journals (Sweden)

    A. D. Mekhtiev

    2014-10-01

    Full Text Available The technology of obtaining nanostructural composite aluminum alloys consists in the plasma injection of refractory nanometric particles with simultaneous two-plane magnetic dynamic mixing of the melt. Particularly important in obtaining composite aluminum matrix alloys is the provision of the introduced particles wettability with the matrix melt for forming stable adhesive bonds. Nanostructured powder components can be considered not only to be a starting product for producing nanostructural composite aluminum alloys but as an independent commerce product. Nanostructural composite metal matrix alloys make one of the most prospective structural materials of the future, and liquid-phase technologies of their obtaining are the most competitive in producing products of nanostructural composite aluminum alloys in the industrial scale.

  10. Impact toughness of laser surface alloyed Aluminium

    CSIR Research Space (South Africa)

    Mabhali, Luyolo AB

    2012-03-01

    Full Text Available Laser surface alloying of aluminium AA1200 was performed with a 4kW Nd:YAG laser and the impact resistance of the alloys was investigated. The alloying powders were a mixture of Ni, Ti and SiC in different proportions. Surfaces reinforced...

  11. Electrical Conductivity of Aluminium Alloy Foams

    Institute of Scientific and Technical Information of China (English)

    凤仪; 郑海务; 朱震刚; 祖方遒

    2002-01-01

    Closed-cell aluminium alloy foams were produced using the powder metallurgical technique. The effect of porosityand cell diameter on the electrical conductivity of foams was investigated and the results were compared with anumber of models. It was found that the percolation theory can be successfully applied to describe the dependenceof the electrical conductivity of aluminium alloy foams on the relative density. The cell diameter has a negligibleeffect on the electrical conductivity of foams.

  12. New aluminium alloys with high lithium content

    Energy Technology Data Exchange (ETDEWEB)

    Schemme, K.; Velten, B.

    1989-06-01

    Since the early 80's there have been made great efforts to replace the high strength aluminium alloys for the aircraft and space industry by a new generation of aluminium-lithium alloys. The attractivity of this kind of alloys could be increased by a further reduction of their density, caused by an increasing lithium content (/ge/ 5 wt.% Li). Therefore binary high-lithium containing alloys with low density are produced and metallografically investigated. A survey of their strength and wear behavior is given by using tensile tests and pin abrasing tests. (orig.).

  13. Investigation of the formability of aluminium alloys at elevated temperatures

    Science.gov (United States)

    Tisza, M.; Budai, D.; Kovács, P. Z.; Lukács, Zs

    2016-11-01

    Aluminium alloys are more and more widely applied in car body manufacturing. Increasing the formability of aluminium alloys are one of the most relevant tasks in todays’ research topics. In this paper, the focus will be on the investigation of the formability of aluminium alloys concerning those material grades that are more widely applied in the automotive industry including the 5xxx and 6xxx aluminium alloy series. Recently, besides the cold forming of aluminium sheets the forming of aluminium alloys at elevated temperatures became a hot research topic, too. In our experimental investigations, we mostly examined the EN AW 5754 and EN AW 6082 aluminium alloys at elevated temperatures. We analysed the effect of various material and process parameters (e.g. temperature, sheet thickness) on the formability of aluminium alloys with particular emphasis on the Forming Limit Diagrams at elevated temperatures in order to find the optimum forming conditions for these alloys.

  14. Impact toughness of laser alloyed aluminium AA1200 alloys

    CSIR Research Space (South Africa)

    Mabhali, Luyolo AB

    2013-08-01

    Full Text Available Laser surface alloying of aluminium AA1200 was performed with a 4kW Nd:YAG laser and impact resistance of the alloys was investigated. The alloying powders were a mixture of Ni, Ti and SiC in different proportions. Surfaces reinforced...

  15. Microstructure Development during Solidification of Aluminium Alloys

    NARCIS (Netherlands)

    Ruvalcaba Jimenez, D.G.

    2009-01-01

    This Thesis demonstrates studies on microstructure development during the solidification of aluminium alloys. New insights of structure development are presented here. Experimental techniques such as quenching and in-situ High-brilliance X-ray microscopy were utilized to study the microstructure evo

  16. A Reaction Coating on Aluminium Alloys by Laser Processing

    NARCIS (Netherlands)

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

    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

  17. 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.

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

    DEFF Research Database (Denmark)

    Din, Rameez Ud; Yuksel, Serkan; Jellesen, Morten Stendahl

    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...... of the effect of vapour pressure, structure of intermetallic particles and thickness of boehmite films on the corrosion behaviour of aluminium alloys....

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

    OpenAIRE

    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.

  20. 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.

  1. Alloys of uranium and aluminium with low aluminium content; Alliages uranium-aluminium a faible teneur en aluminium

    Energy Technology Data Exchange (ETDEWEB)

    Cabane, G.; Englander, M.; Lehmann, J. [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires

    1955-07-01

    Uranium, as obtained after spinning in phase {gamma}, presents an heterogeneous structure with large size grains. The anisotropic structure of the metal leads to an important buckling and surface distortion of the fuel slug which is incompatible with its tubular cladding for nuclear fuel uses. Different treatments have been made to obtain an isotropic structure presenting high thermal stability (laminating, hammering and spinning in phase {alpha}) without success. Alloys of uranium and aluminium with low aluminium content present important advantage in respect of non allied uranium. The introduction of aluminium in the form of intermetallic compound (UAl{sub 2}) gives a better resistance to thermal fatigue. Alloys obtained from raw casting present an improved buckling and surface distortion in respect of pure uranium. This improvement is obtained with uranium containing between 0,15 and 0,5 % of aluminium. An even more improvement in thermal stability is obtained by thermal treatments of these alloys. These new characteristics are explained by the fine dispersion of the UAl{sub 2} particles in uranium. The results after treatments obtained from an alloy slug containing 0,4 % of aluminium show no buckling or surface distortion and no elongation. (M.P.)

  2. 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.

  3. 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.

  4. Combined Corrosion and Wear of Aluminium Alloy 7075-T6

    NARCIS (Netherlands)

    Liu, Y.; Mol, J.M.C.; Janssen, G.C.A.M.

    2016-01-01

    The aluminium alloy 7075-T6 is widely used in engineering. In some applications, like slurry transport, corrosion and abrasion occur simultaneously, resulting in early material failure. In the present work, we investigated the combined effect of corrosion and wear on the aluminium alloy 7075-T6. We

  5. Combined Corrosion and Wear of Aluminium Alloy 7075-T6

    NARCIS (Netherlands)

    Liu, Y.; Mol, J.M.C.; Janssen, G.C.A.M.

    2016-01-01

    The aluminium alloy 7075-T6 is widely used in engineering. In some applications, like slurry transport, corrosion and abrasion occur simultaneously, resulting in early material failure. In the present work, we investigated the combined effect of corrosion and wear on the aluminium alloy 7075-T6. We

  6. Forming of aluminium alloy friction stir welds

    Science.gov (United States)

    Bruni, Carlo

    2016-10-01

    The present paper aims at investigating, through analytical models, numerical models and experiments, the effect of the warm deformation phase, realised with an in temperature upsetting, on the weld previously performed by friction stir lap welding on aluminium alloy blanks. The investigation allows to show the deformation zones after upsetting that determine the homogenisation of the weld section. The analytical model allows to relate the friction factor with the upsetting load. The presence on the weld of not elevated friction factor values determines the deformation and localisation levels very useful for the weld. Such methodology allows to improve the weld itself with the forming phase.

  7. Deviatoric response of the aluminium alloy, 5083

    Science.gov (United States)

    Appleby-Thomas, Gareth; Hazell, Paul; Millett, Jeremy; Bourne, Neil

    2009-06-01

    Aluminium alloys such as 5083 are established light weight armour materials. As such, the shock response of these materials is of great importance. The shear strength of a material under shock loading provides an insight into its ballistic performance. In this investigation embedded manganin stress gauges have been employed to measure both the longitudinal and lateral components of stress during plate impact experiments over a range of impact stresses. In turn, these results were used to determine the shear strength and to investigate the time dependence of lateral stress behind the shock front to give an indication of material response.

  8. 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

  9. 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.

  10. A Reaction Coating on Aluminium Alloys by Laser Processing

    OpenAIRE

    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.

  11. 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

  12. Three body abrasion of laser surface alloyed aluminium AA1200

    CSIR Research Space (South Africa)

    Mabhali, Luyolo AB

    2012-06-01

    Full Text Available on the composition of the alloying powder mixture. The wear performance of the alloyed surfaces was characterised using an ASTM G65 three body dry abrasion apparatus. A maximum 82% improvement in the wear resistance of the pure aluminium was achieved with a 40 wt% Ni...

  13. Incremental forming of aluminium alloys in cryogenic environment

    Science.gov (United States)

    Vanhove, Hans; Mohammadi, Amirahmad; Duflou, Joost R.

    2016-10-01

    Incremental Sheet Forming processes suffer from stringent forming limits, restricting the range of producible geometries. Through in-process cooling of the sheet to cryogenic level, this paper explores the potential of altering material properties benefiting the formability and residual hardness of different aluminium alloys. Global cooling of aluminium sheets with liquid nitrogen and dry ice allows to reach temperatures of 78K and 193K respectively. Extended with experiments at room temperature (293K), these tests form a base for comparison of surface quality, formability and residual hardness. As an aluminium alloy commonly used for its high strength to weight ratio, but suffering from limited formability compared to draw-quality steels, AA5083-H111 is of interest for cryogenic treatment. AA1050-H24 is included in the test campaign as a base for commercially pure aluminium.

  14. Metal-Ceramic Interfaces in Laser Coated Aluminium Alloys

    NARCIS (Netherlands)

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

    1994-01-01

    A novel process was developed to firmly coat an aluminium alloy, Al6061, with α-Al2O3 by means of laser processing. In this approach a mixture of SiO2 and Al powder was used to inject in the laser melted surface of aluminium. A reaction product α-Al2O3 layer of a thickness of 100 µm was created whic

  15. Constitutive modelling of aluminium alloy sheet at warm forming temperatures

    Science.gov (United States)

    Kurukuri, S.; Worswick, M. J.; Winkler, S.

    2016-08-01

    The formability of aluminium alloy sheet can be greatly improved by warm forming. However predicting constitutive behaviour under warm forming conditions is a challenge for aluminium alloys due to strong, coupled temperature- and rate-sensitivity. In this work, uniaxial tensile characterization of 0.5 mm thick fully annealed aluminium alloy brazing sheet, widely used in the fabrication of automotive heat exchanger components, is performed at various temperatures (25 to 250 °C) and strain rates (0.002 and 0.02 s-1). In order to capture the observed rate- and temperature-dependent work hardening behaviour, a phenomenological extended-Nadai model and the physically based (i) Bergstrom and (ii) Nes models are considered and compared. It is demonstrated that the Nes model is able to accurately describe the flow stress of AA3003 sheet at different temperatures, strain rates and instantaneous strain rate jumps.

  16. Hardfacing of aluminium alloys by means of metal matrix composites produced by laser surface alloying

    CSIR Research Space (South Africa)

    Pityana, SL

    2009-06-01

    Full Text Available Metal matrix composite layers were formed on an aluminium substrate by means of laser surface alloying method. Aluminium 1200 was used as a host material and TiC particles were used as the reinforcement. The microstructure of the modified layer...

  17. China Rescinds the Export Tax on Aluminium Alloys Made by Scrap

    Institute of Scientific and Technical Information of China (English)

    2005-01-01

    <正>According to an official from the Tax Regulations Office under China’s State Council, from July 1st 2005, China will rescind the 5 per cent export tax on the aluminium alloys produced by using aluminium alloys scrap. An official from the State Council’s office said that through investigation they found that most aluminium alloys produced from aluminium scrap are not that energy consuming compared to primary aluminium. Starting from January 1st 2005, China decided to collect 5 per cent export tax on aluminium so as to control the industry development connected with high energy cost.

  18. The erosion resistance of tool alloys in foundry melt the Zamak 4 - 1

    Science.gov (United States)

    Muhametzyanova, GF; Kolesnikov, M. S.; Muhametzyanov, I. R.

    2016-06-01

    The paper considers the resistance against erosion dissolution in the melt of foundry Zamak 4 - 1 die steels used for press machine parts manufacturing for injection molding, and hard alloys system WC - Co. It is established that the solubility in the melt Zamak - 4 - 1 steel of 4H5MFS and DI - 22 are promising for the parts fabrication of metal-wire casting machines of CLT and IDRA types. A significant reserve to increase the resistance of metal wires is the use of cast steel, as well as in electroslag and electro-beam remelting options. Metal-ceramic alloy doped with chromium VK25H may be recommended for reinforcement of heavily loaded parts of the press-nodes of hot casting machines under pressure.

  19. Intermetallic particles-induced pitting corrosion in 6061-T651 aluminium alloy

    CSIR Research Space (South Africa)

    Mutombo, K

    2011-07-01

    Full Text Available -Induced Pitting Corrosion in 6061-T651 Aluminium Alloy Kalenda Mutombo Council for Scientific and Industrial Research (CSIR), South Africa kmutombo@csir.co.za Keywords: pitting corrosion, 6061-T651 aluminium alloy, intermetallic particles, 3.5% Na... extrudability, reasonable weldability and good corrosion resistance. This alloy finds widespread application in ship building and in the fabrication of tank containers for transporting various liquids. 6061-T651 aluminium alloy is, however, prone to pitting...

  20. 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.

  1. Implants for surgery -- Metallic materials -- Part 3: Wrought titanium 6-aluminium 4-vanadium alloy

    CERN Document Server

    International Organization for Standardization. Geneva

    1996-01-01

    Specifies the characteristics of, and corresponding test methods for, the wrought titanium alloy known as titanium 6-aluminium 4-vanadium alloy (Ti 6-Al 4-V alloy) for use in the manufacture of surgical implants.

  2. TECHNOLOGICAL COMPLEX OF EQUIPMENT FOR REFINING AND CASTING OF STEEL AND ALLOYS IN THE FOUNDRY AND STEEL INDUSTRIES

    Directory of Open Access Journals (Sweden)

    V. I. Zolotukhin

    2013-01-01

    Full Text Available Vulcan TM is a small innovative company, specializing in the manufacture of steel and alloys casting systems and refractory accessories.Available for foundry and metallurgical industries, special technological equipment, designed and manufactured by LLC NPP “Vulkan-TM.”

  3. Steam generated conversion coating on aluminium alloys

    DEFF Research Database (Denmark)

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

    pressure steam produced by an autoclave at a temperature of 107 – 121 °C and pressure of 15 -17 psi for 10 minutes to produce a thin coating of aluminium oxide. The aim of this study is to understand the effect of high pressure steam with and without different chemical additives on surface morphology...

  4. Numerical Modelling of Drawbeads for Forming of Aluminium Alloys

    DEFF Research Database (Denmark)

    Joshi, Y; Christiansen, Peter; Masters, I

    2016-01-01

    The drawbeads in stamping tools are usually designed based on experience from the forming of steel. However, aluminium alloys display different forming behaviour to steels, which is not reflected in the drawbead design for tools used for stamping aluminium. This paper presents experimental results...... from different semi-circular drawbead geometries commonly encountered in automotive dies and compares them to those obtained from Stoughton’s analytical drawbead model and the 2D plane strain drawbead model set up using LS-DYNA.The study was conducted on lubricated NG5754 strips. The results presented...

  5. 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. 

  6. Foundry technology and its applications of ductile iron castings produced by water-cooled copper alloy mold

    Institute of Scientific and Technical Information of China (English)

    2004-01-01

    The high efficiency mechanized foundry technology of castings produced by using water-cooled copper alloy permanent mold has been systematically studied. Through the researching a Cu-Cr-Mg alloy with high conductivity and good combined mechanical properties used for making permanent mold was developed, and the basic design principles of the water-cooled permanent mold along with the control-range of relevant foundry processing parameters were also established.A cast production line equipped with water-cooled copper alloy mold was designed and fabricated for production of ductile iron automobile gear castings. This production line can consistently make automobile gear castings in QT500-15 and QT600-5 (Chinese Standard) grades of ductile iron with up to 95 % casting success rate.

  7. 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......) 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...

  8. Carbon treated commercial aluminium alloys as anodes for aluminium-air batteries in sodium chloride electrolyte

    Science.gov (United States)

    Pino, M.; Herranz, D.; Chacón, J.; Fatás, E.; Ocón, P.

    2016-09-01

    An easy treatment based in carbon layer deposition into aluminium alloys is presented to enhance the performance of Al-air primary batteries with neutral pH electrolyte. The jellification of aluminate in the anode surface is described and avoided by the carbon covering. Treated commercial Al alloys namely Al1085 and Al7475 are tested as anodes achieving specific capacities above 1.2 Ah g-1vs 0.5 Ah g-1 without carbon covering. The influence of the binder proportion in the treatment as well as different carbonaceous materials, Carbon Black, Graphene and Pyrolytic Graphite are evaluated as candidates for the covering. Current densities of 1-10 mA cm-2 are measured and the influence of the alloy explored. A final battery design of 4 cells in series is presented for discharges with a voltage plateau of 2 V and 1 Wh g-1 energy density.

  9. Recycling of Glass Fibre Reinforced Aluminium Laminates and Silicon Removal from Aerospace Al Alloy

    NARCIS (Netherlands)

    Zhu, G.

    2012-01-01

    Aerospace aluminium alloys (7xxx and 2xxx series Al alloy) is one of the important Al alloys in our life. The recycling of aerospace Al alloy plays a significant role in sustainable development of Al industry. The fibre reinforced metal laminates GLARE including 67 wt.% 2024 Al alloy was used as upp

  10. Evolution of morphology in solidifying aluminium alloys

    NARCIS (Netherlands)

    Dijkstra, W.O.

    2007-01-01

    In the thesis two different models of solidification of aluminum alloys are presented and analyzed. The first 1--D solidification model is derived from the conservation of solute, heat and mass. With numerical experiments it is shown that simulations with the Finite Difference discretization must

  11. 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...

  12. High strain rate superplastic aluminium alloys: the way forward?

    Energy Technology Data Exchange (ETDEWEB)

    Grimes, R.; Dashwood, R.J.; Flower, H.M. [Imperial Coll. of Science, Technology and Medicine, London (United Kingdom). Dept. of Materials

    2001-07-01

    The technical and commercial barriers to the development and successful exploitation of a high strain rate superplastically deformable aluminium alloy for use in the automotive industry are considered in this paper. Batch processing routes, such as mechanical alloying or equal channel angular extrusion, employed to deliver appropriate chemistry and structure, are inherently costly and unlikely to deliver either the quantity or the size of strip required commercially. There is evidence that there is still scope for development of conventional casting and rolling routes, but a particulate casting route combined with roll consolidation offers the prospect of a commercially viable Al-Mg-Zr product. The use of alloying additions, including zirconium, is also discussed and comparative costs are presented: on this basis the use of scandium appears economically prohibitive. (orig.)

  13. Hot Deformation Of 6xxx Series Aluminium Alloys

    Directory of Open Access Journals (Sweden)

    Mrówka-Nowotnik G.

    2015-06-01

    Full Text Available The hot deformation behavior of the 6xxx aluminum alloys was investigated by compression tests in the temperature range 100°C-375°C and strain rate range 10−4s−1 and 4×10−4s−1 using dilatometer DIL 805 BÄHR Thermoanalyse equipped with accessory attachment deformation allows the process to execute thermoplastic in vacuum and inert gas atmosphere. Associated microstructural changes of characteristic states of examined alloys were studied by using the transmission electron microscope (TEM. The results show that the stress level decreases with increasing deformation temperature and deformation rate. And was also found that the activation energy Q strongly depends on both, the temperature and rate of deformation. The results of TEM observation showing that the dynamic flow softening is mainly as the result of dynamic recovery and recrystallization of 6xxx aluminium alloys.

  14. Nanostructural hierarchy increases the strength of aluminium alloys.

    Science.gov (United States)

    Liddicoat, Peter V; Liao, Xiao-Zhou; Zhao, Yonghao; Zhu, Yuntian; Murashkin, Maxim Y; Lavernia, Enrique J; Valiev, Ruslan Z; Ringer, Simon P

    2010-09-07

    Increasing the strength of metallic alloys while maintaining formability is an interesting challenge for enabling new generations of lightweight structures and technologies. In this paper, we engineer aluminium alloys to contain a hierarchy of nanostructures and possess mechanical properties that expand known performance boundaries-an aerospace-grade 7075 alloy exhibits a yield strength and uniform elongation approaching 1 GPa and 5%, respectively. The nanostructural architecture was observed using novel high-resolution microscopy techniques and comprises a solid solution, free of precipitation, featuring (i) a high density of dislocations, (ii) subnanometre intragranular solute clusters, (iii) two geometries of nanometre-scale intergranular solute structures and (iv) grain sizes tens of nanometres in diameter. Our results demonstrate that this novel architecture offers a design pathway towards a new generation of super-strong materials with new regimes of property-performance space.

  15. 3D printing of high-strength aluminium alloys.

    Science.gov (United States)

    Martin, John H; Yahata, Brennan D; Hundley, Jacob M; Mayer, Justin A; Schaedler, Tobias A; Pollock, Tresa M

    2017-09-20

    Metal-based additive manufacturing, or three-dimensional (3D) printing, is a potentially disruptive technology across multiple industries, including the aerospace, biomedical and automotive industries. Building up metal components layer by layer increases design freedom and manufacturing flexibility, thereby enabling complex geometries, increased product customization and shorter time to market, while eliminating traditional economy-of-scale constraints. However, currently only a few alloys, the most relevant being AlSi10Mg, TiAl6V4, CoCr and Inconel 718, can be reliably printed; the vast majority of the more than 5,500 alloys in use today cannot be additively manufactured because the melting and solidification dynamics during the printing process lead to intolerable microstructures with large columnar grains and periodic cracks. Here we demonstrate that these issues can be resolved by introducing nanoparticles of nucleants that control solidification during additive manufacturing. We selected the nucleants on the basis of crystallographic information and assembled them onto 7075 and 6061 series aluminium alloy powders. After functionalization with the nucleants, we found that these high-strength aluminium alloys, which were previously incompatible with additive manufacturing, could be processed successfully using selective laser melting. Crack-free, equiaxed (that is, with grains roughly equal in length, width and height), fine-grained microstructures were achieved, resulting in material strengths comparable to that of wrought material. Our approach to metal-based additive manufacturing is applicable to a wide range of alloys and can be implemented using a range of additive machines. It thus provides a foundation for broad industrial applicability, including where electron-beam melting or directed-energy-deposition techniques are used instead of selective laser melting, and will enable additive manufacturing of other alloy systems, such as non-weldable nickel

  16. Steam assisted oxide growth on aluminium alloys using oxidative chemistries: Part II corrosion performance

    DEFF Research Database (Denmark)

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

    2015-01-01

    Surface treatment of aluminium alloys using steam with oxidative chemistries, namely KMnO4 and HNO3 resulted in accelerated growth of oxide on aluminium alloys. Detailed investigation of the corrosion performance of the treated surfaces was carried out using potentiodynamic polarisation...

  17. Microstructures of alloyed and dispersed hard particles in the aluminium surface

    CSIR Research Space (South Africa)

    Pityana, S

    2010-03-01

    Full Text Available Laser surface alloying of A1200 aluminium alloy was carried out using a 4.4 kW Nd:YAG laser. Powder mixtures of SiC and TiC hard particles were injected into the laser generated melt pool on the aluminium substrate using a commercial powder feeder...

  18. Aluminium. II - A review of deformation properties of high purity aluminium and dilute aluminium alloys.

    Science.gov (United States)

    Reed, R. P.

    1972-01-01

    The elastic and plastic deformation behavior of high-purity aluminum and of dilute aluminum alloys is reviewed. Reliable property data, including elastic moduli, elastic coefficients, tensile, creep, fatigue, hardness, and impact are presented. Single crystal tensile results are discussed. Rather comprehensive reference lists, containing publications of the past 20 years, are included for each of the above categories. Defect structures and mechanisms responsible for mechanical behavior are presented. Strengthening techniques (alloys, cold work, irradiation, quenching, composites) and recovery are briefly reviewed.

  19. Optimal modifying and refining processes for A356 aluminium alloys

    Institute of Scientific and Technical Information of China (English)

    ZUO Xiu-rong; ZHONG Zhi-guo

    2006-01-01

    The influence of Ti, B, RE (cerium-rich mixtures of rare earth) and Sr, applied in modification and refining processes, on A356 aluminum alloys has been studied with the aids of OM, etc. The results show that the grain refining efficiency of Grain-Refining Aluminium Ingot (GRAI) and Al-Ti master alloys is similar. But the Ti addition from GRAI has lower costs than that with Al-Ti master alloys. So A356 aluminum alloys produced with GRAI are feasible in economy.Grain refining with GRAI with 0.01%Ti plus additional 0.03% B offers significant advantages over that from GRAI with 0.1% Ti only in A356 aluminum alloys, which made the dendrite α (Al) grain structure transform into equiaxed α (Al) grain structure, plus a partially modified eutectic silicon structure. RE addition to A356 aluminum alloys with Sr modifier is enable to achieve small DAS,reduced pores, well-refined fibrous silicon, small and dispersive eutectic colonies.

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

    Directory of Open Access Journals (Sweden)

    Mudigere Krishnegowda Pavithra

    2015-12-01

    Full Text Available 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 uninhibited metal samples was examined by scanning electron microscopy. 

  1. Foaming of aluminium-silicon alloy using concentrated solar energy

    Energy Technology Data Exchange (ETDEWEB)

    Cambronero, L.E.G.; Ruiz-Roman, J.M. [Grupo de Materiales Hibridos, ETSIM-UPM, Madrid, Rios Rosas 21, 28003 Madrid (Spain); Canadas, I.; Martinez, D. [Plataforma Solar de Almeria, CIEMAT, P.O. Box 22, 04200 Tabernas (Almeria) (Spain)

    2010-06-15

    Solar energy is used for the work reported here as a nonconventional heating system to produce aluminium foam from Al-Si alloy precursors produced by powder metallurgy. A commercial precursor in cylindrical bars enclosed in a stainless-steel mould was heated under concentrated solar radiation in a solar furnace with varied heating conditions (heating rate, time, and temperature). Concentrated solar energy close to 300 W/cm{sup 2} on the mould is high enough to achieve complete foaming after heating for only 200 s. Under these conditions, the density and pore distribution in the foam change depending on the solar heating parameters and mould design. (author)

  2. 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.

  3. 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...... initiate doxide growth at the intermetallic particles while growth and corrosion performance of oxide was found tobe a function of anions type and their concentration. Further, steam treatment with phosphates exhibited better performance under acetic acid salt spray and filiform corrosion test whereas...

  4. Release Behaviour of Shock Loaded LY12 Aluminium Alloy

    Institute of Scientific and Technical Information of China (English)

    YAN Min; DAI Lan-Hong; SHEN Le-Tian

    2005-01-01

    @@ By making use of a light gas gun, a specially designed target is impacted by the LY12 flyer, and the pressure is taken in the range of 0.6-3 GPa. Based on the stress profiles measured in the buffer materials by manganese gauges, the Hugoniot curve and release curves of LY12 aluminium alloy are obtained. Meanwhile, the release curves from different initial shocked states are described in both the pressure-particle velocity plane and the pressure-specific volume plane.

  5. Deviatoric Response of AN Armour-Grade Aluminium Alloy

    Science.gov (United States)

    Appleby-Thomas, G. J.; Hazell, P. J.; Millett, J.; Bourne, N. K.

    2009-12-01

    Aluminium alloys such as 5083 H32 are established light-weight armour materials. As such, the shock response of these materials is of great importance. The shear strength of a material under shock loading provides an insight into its ballistic performance. In this investigation embedded manganin stress gauges have been employed to measure both the longitudinal and lateral components of stress during plate-impact experiments over a range of impact stresses. In turn, these results were used to determine the shear strength and to investigate the time dependence of lateral stress behind the shock front to give an indication of material response.

  6. Steam Initiated Surface Modification of Aluminium Alloys

    DEFF Research Database (Denmark)

    Din, Rameez Ud

    -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 interface structure of the coatings were analysed using SEM, FIB-SEM,TEM, GI-XRD, FTIR, XPS, AFM, contact angle, and boiling test. Chapter 1 of this thesis provides a background to the work and available literature information. Materials and experimental methods are outlined in chapter 2. The chapters 3...... using autoclave or using spray system, and with or without various chemistries as accelerators. In general, results show the formation of 650 nm – 3000 nm thick conversion coating, where the thickness depend on the treatment parameters and steam chemistry. Further, the formed coating provide good...

  7. Fractographic analysis of fatigue damage in 7000 aluminium alloys.

    Science.gov (United States)

    Cvijović, Z; Vratnica, M; Gerić, K

    2008-12-01

    In this paper, an attempt is made to correlate the fatigue damage in 7000 aluminium alloys with different impurity contents to the microstructural features and to explain their interdependence through fractographic observations. The Paris constants of these alloys in the form of hot-forged plates subjected to the overaged T73 temper are evaluated and differences in the fatigue crack growth rate described by striation spacing measurements. Scanning electron microscopy analysis of fatigue fracture surfaces revealed that the type and morphological parameters of coarse intermetallic particles play a critical role in fatigue crack growth behaviour. The elemental distribution determined by means of energy-dispersive spectroscopy analysis showed that the fractured particles accelerating the crack advances are larger particles of Fe-rich phases. The fatigue crack growth rate increases considerably with increasing amounts of these particles. The smaller eta, S and Mg(2)Si particles contribute beneficially to fatigue life.

  8. Laser surface alloying of aluminium-transition metal alloys

    Directory of Open Access Journals (Sweden)

    Almeida, A.

    1998-04-01

    Full Text Available Laser surface alloying has been used as a tool to produce hard and corrosion resistant Al-transition metal (TM alloys. Cr and Mo are particularly interesting alloying elements to produce stable highstrength alloys because they present low diffusion coefficients and solid solubility in Al. To produce Al-TM surface alloys a two-step laser process was developed: firstly, the material is alloyed using low scanning speed and secondly, the microstructure is modified by a refinement step. This process was used in the production of Al-Cr, Al-Mo and Al-Nb surface alloys by alloying Cr, Mo or Nb powder into an Al and 7175 Al alloy substrate using a CO2 laser. This paper presents a review of the work that has been developed at Instituto Superior Tecnico on laser alloying of Al-TM alloys, over the last years.

    En el presente trabajo se estudia la aleación superficial mediante láser de aluminio con metales de transición. El cromo y el molibdeno son particularmente interesantes porque producen aleaciones de alta resistencia y por el bajo coeficiente de difusión y solución sólida en aluminio. Para producir estas aleaciones se ha seguido un procedimiento desarrollado en dos partes. En primer lugar, el material se alea usando una baja velocidad de procesado y en segundo lugar la estructura se modifica mediante un refinamiento posterior. Este procedimiento se ha empleado en la producción de aleaciones Al-Cr, Al-Mo y Al-Nb mediante aleación con láser de CO2 de polvos de Cr, Mo o Nb en aluminio y la aleación 7175. Este trabajo es una revisión del desarrollado en el Instituto Superior Técnico de Lisboa en los últimos años.

  9. 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.

  10. Electrolytic deposition of aluminium-magnesium-alloys from electrolytes containing organo-aluminium complexes; Elektrolytische Abscheidung von Aluminium-Magnesium-Legierungen aus aluminiumorganischen Komplexelektrolyten

    Energy Technology Data Exchange (ETDEWEB)

    Lehmkuhl, H.; Mehler, K.; Bongard, H.; Tesche, B. [Max-Planck-Institut fuer Kohlenforschung, Muelheim an der Ruhr (Germany); Reinhold, B. [Audi AG, Ingolstadt (Germany). Technische Entwicklung

    2000-10-01

    The galvanic deposition of pure aluminium from fluoride-containing electrolytes has been developed further and for the first time aluminium and magnesium have been deposited from a toluene-solution of a halide-free organo-aluminium complex electrolyte. The rate of incorporation of magnesium can be controlled over a wide range by either adjusting the composition of the aluminium-magnesium anode or by using separate aluminium or magnesium anodic circuits. The current efficiency for both anode and cathode approaches 100%. The resulting coating is optically attractive and, depending upon the magnesium-content or the cathodic current density, can be formed as a dull or polished surface. Investigations using an electron microscope show that the surface, in contrast to that of pure aluminium, consists of spherical particles. The aluminium-magnesium coating provides excellent protection against the corrosion of magnesium components. Electrochemical investigations using, for example 25% by weight magnesium incorporation, indicate a pronounced passivity interval compared to the alloy AZ91hp. In contrast to galvanic zinc-plated and silicate-sealed examples, cyclic corrosion tests on screws simulating 10 years of exposure, show no corrosion. (orig.)

  11. 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

  12. Domestic Output of Aluminium Alloy Hub Surpassing 70 million in 2007

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    <正>According to a report from the hub branch of China Association of Automobile Manufactur- ers,China has produced a total of more than 70 million aluminium alloy hubs in 2007,a year- on-year growth over 25%,while consuming over 700,000 tons of primary aluminium the whole year.

  13. Microstructure and interfaces of a reaction coating on aluminium alloys by laser processing

    NARCIS (Netherlands)

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

    1993-01-01

    This paper reports an approach to coat a ceramic layer on aluminium alloys by means of chemical reaction. The reaction product of Al2O3 layer of 100 µm in thickness has been formed using a powder mixture of silicon oxide and aluminium by laser processing. It turns out that the large amount of heat f

  14. Cold compression residual stress reduction in aluminium alloy 7010

    Energy Technology Data Exchange (ETDEWEB)

    Tanner, D.A. [Limerick Univ. (Ireland). Materials Research Centre; Robinson, J.S. [Dept. of Materials Science and Technology, Univ. of Limerick (Ireland); Cudd, R.L. [HDA Forgings Ltd., Redditch, Worchestershire (United Kingdom)

    2000-07-01

    7010 is one of the high strength aluminium alloys used mainly as plate and forgings in the aerospace industry. Its high strength is achieved through a quenching operation where the material is rapidly cooled from the solution heat treatment temperature (475 C) to room temperature. As with all rapid quenching operations, residual stresses develop, leaving the material unsuitable for further machining operations and for service. Regular shaped forgings are generally cold compressed after quenching to relieve residual stresses. The effect of friction, increasing/decreasing the amount of cold compression and applying cold compression in 'bites' on residual stress magnitudes is unknown. This paper aims to study the effect that these variables have on final residual stress patterns through use of a finite element model. (orig.)

  15. In-situ electron microscopy studies on the tensile deformation mechanisms in aluminium 5083 alloy

    CSIR Research Space (South Africa)

    Motsi, G

    2014-10-01

    Full Text Available In this study tensile deformation mechanisms of aluminium alloy 5083 were investigated under observations made from SEM equipped with a tensile stage. Observations during tensile testing revealed a sequence of surface deformation events...

  16. Strength properties examination of high zinc aluminium alloys inoculated with Ti addition

    National Research Council Canada - National Science Library

    J.Bura? M.Szucki G.Piwowarski W.K.Krajewski P.K.Krajewski

    2017-01-01

    This paper includes studies on the influence of grain refinement treatment with respect to the composition and structure of high zinc aluminium casting alloys on the changes of their tensile properties. The Al-20 wt...

  17. Prediction of flow stress of 7017 aluminium alloy under high strain ratecompression at elevated temperatures

    National Research Council Canada - National Science Library

    Ravindranadh BOBBILI B. RAMAKRISHNA V. MADHU A.K. GOGIA

    2015-01-01

    An artificial neural network (ANN) constitutive model and Johnson-Cook (J-C) model were developed for 7017 aluminium alloy based on high strain rate data generated from split Hopkinson pressure bar (SHPB...

  18. Prediction of flow stress of 7017 aluminium alloy under high strain rate compression at elevated temperatures

    National Research Council Canada - National Science Library

    Bobbili, Ravindranadh; Ramakrishna, B; Madhu, V; Gogia, A.K

    2015-01-01

    An artificial neural network (ANN) constitutive model and Johnson–Cook (J–C) model were developed for 7017 aluminium alloy based on high strain rate data generated from split Hopkinson pressure bar (SHPB...

  19. Recovery of actinides from actinide-aluminium alloys by chlorination: Part I

    OpenAIRE

    Cassayre, Laurent; Soucek, Pavel; Mendes, Eric; Malmbeck, Rikard; Nourry, Christophe; Eloirdi, Rachel; Glatz, Jean-Paul

    2011-01-01

    Pyrochemical processes in molten LiCl–KCl are being developed in ITU for recovery of actinides from spent nuclear fuel. The fuel is anodically dissolved to the molten salt electrolyte and actinides are electrochemically reduced on solid aluminium cathodes forming solid actinide–aluminium alloys. A chlorination route is being investigated for recovery of actinides from the alloys. This route consists in three steps: Vacuum distillation for removal of the salt adhered on the electrode, chlorina...

  20. Corrosion behaviour of 6063 aluminium alloy in acidic and in alkaline media

    OpenAIRE

    Deepa, Prabhu; Padmalatha, Rao

    2017-01-01

    The corrosion behaviour of 6063 aluminium alloy was investigated in different concentrations of phosphoric acid medium and sodium hydroxide medium at different temperatures. The study was done by electrochemical method, using Tafel polarization technique and electrochemical impedance spectroscopy (EIS) technique. The surface morphology was investigated using scanning electron microscope (SEM) with Energy-dispersive X-ray spectroscopy (EDX). The results showed that the 6063 aluminium alloy und...

  1. Radiation resistance and parameters of activation of aluminium-magnesium-scandium and aluminium-magnesium-vanadium alloys under neutron irradiation

    Energy Technology Data Exchange (ETDEWEB)

    Ivanov, L.I.; Ivanov, V.V.; Lazorenko, V.M.; Platov, Yu.M.; Tovtin, V.I.; Toropova, L.S. (A.A. Baikov Inst. of Metallurgy, Academy of Sciences, Moscow (Russia))

    1992-09-01

    Alloys Al-2.24Mg-0.223Sc-0.04Zr, Al-2.24Mg-0.12Sc-0.04Zr, and Al-2.24Mg-0.05V (at.%) annealed at 150deg C and 400deg C were irradiated at [approx equal] 70 and [approx equal] 150deg C in the SM-2 reactor. The maximum neutron fluence was 4.7x10[sup 24] m[sup -2] (E > 0.1 MeV). The tensile tests were carried out in the temperature range 20 to 350deg C. Alloy Al-2.24 Mg-0.23Sc-0.04Zr annealed at 400deg C and alloy Al-2.24Mg-0.12Sc-0.04Zr annealed at 150deg C at all test temperatures retained good mechanical properties after irradiation. The mechanisms for the radiation resistance of aluminium-scandium and aluminium-magnesium-scandium alloys are discussed. Calculations of induced radioactivity and its decay behaviour after shutdown in aluminium and Al-2.24Mg-(0.12-0.23)Sc alloys were carried out. Composition of the radionuclides in these materials after irradiation in the SM-2 reactor were also determined using a gamma-spectroscopy technique. (orig.).

  2. Emeraldine base as corrosion protective layer on aluminium alloy AA5182, effect of the surface microstructure

    DEFF Research Database (Denmark)

    Cecchetto, L; Ambat, Rajan; Davenport, A.J.

    2007-01-01

    AA5182 aluminium alloy cold rolled samples were coated by thin Wlms of emeraldine base (EB) obtained from a 5% solution in N-methylpyrrolidinone. Accelerated corrosion tests prove this coating very eVective for corrosion protection of aluminium alloys in neutral environment. This study underlines......: • a weak redox activity of the polymer which passivate the metal, • a proton involving self-healing process taking place at the polymer–metal interface, which contributes to delay local acidiWcation in Wrst steps of corrosion on EB coated aluminium surfaces....

  3. Microstructure and properties of hot compacted powders of aluminium alloys.

    Science.gov (United States)

    Lityńska-Dobrzyńska, L; Dutkiewicz, J; Maziarz, W; Kanciruk, A

    2009-11-01

    Atomized 6061 aluminium alloy powders with and without the addition of 2 wt% Zr were milled for 80 h in a planetary ball mill and hot pressed in vacuum. The milled powders showed microhardness of about 170 HV, which increased after hot pressing up to 260 HV and up to 280 HV for powders without and with the Zr additions, respectively. Compression tests showed the high yield stress of 300 MPa obtained for the hot-pressed sample produced from the initial powders compared with ultimate compression strength of above 800 MPa for that of the milled sample and slightly higher for that with Zr additions. The effect of hot pressing on the structure of powders was investigated using a conventional analytical and high-resolution electron microscopy and high angle annular dark-field scanning transmission electron microscopy combined with energy dispersive X-ray microanalysis. The samples of initial powders hot pressed in vacuum showed a cell structure with particles of the Mg(2)Si and AlFeSi phases in intercell areas. In the milled and hot-pressed sample, the homogeneous structure of small grains of size below 200 nm was observed. The AlFeSi and Mg(2)Si particles with size 20-100 nm were uniformly distributed as well as the Zr rich particles in the Zr containing alloy. The Zr-rich particles containing up to 80 at% Zr were identified as a metastable fcc cubic phase with lattice parameter a= 0.48 nm.

  4. Pitting corrosion of A357 aluminium alloy obtained by semisolid processing

    Energy Technology Data Exchange (ETDEWEB)

    Bastidas, J.M.; Polo, J.L.; Torres, C.L. [National Centre for Metallurgical Research (CSIC), Madrid (Spain); Forn, A.; Baile, M.T. [Polytechnic Univ. of Catalonia, Vilanova i la Geltru (Spain)

    2001-09-01

    This paper studies the pitting corrosion of a structural component of A357 aluminium alloy obtained by a semisolid metal forming process. The mechanical properties of the A357 alloy were improved by applying standard heat treatments T5 and T6. Impedance measurements were conducted at the rest potential and polarisation curves were plotted using a 3% NaCl test solution. After polarisation experiments the specimens were analysed by scanning electron microscopy. The corrosion process is favoured through the eutectic regions. The results show that T6 heat treatment improved the corrosion resistance of the A357 aluminium alloy. (orig.)

  5. Thermomechanical properties and fracture of resin-bonded-sand cores - Experimental study and application in aluminium foundry

    Science.gov (United States)

    Menet, Claire; Reynaud, Pascal; Fantozzi, Gilbert; Thibault, Delphine; Laforêt, Adrien

    2017-06-01

    Sand cores are used to produce internal cavities of metallic cast parts with complex shapes like automotive cylinder heads. Foundry cores are granular materials made of sand grains aggregated with binder bridges. In the cold box coring process, the binder is a polyurethane resin. It is noteworthy that during the casting of the liquid metal, the polymer binder is seriously damaged. This kind of materials has been poorly investigated so far. This study aims for a better understanding of the mechanical behaviour and fracture of cores subjected to various loads and thermal ageing. Particularly, the focus is on the decoring step, which consists in removing the sand by hammering and vibration of the metallic part after casting. This major project, generated from the collaboration of the aluminum casting company Montupet, and two laboratories Centre des Matériaux (CdM) and MATEIS, includes both experimental and numerical activities in order to model the decoring step of cylinder heads based on empiric data. Here, the experimental part of the work is presented.

  6. Investigation of the properties of aluminium alloys used in the construction of nuclear research reactors

    Energy Technology Data Exchange (ETDEWEB)

    Hajewska, E. [Institute of Atomic Energy, Otwock-Swierk (Poland)

    1993-11-01

    In the paper there are described the results of the studies of the properties of aluminium alloys using in the construction of research reactors, especially of the Polish alloy PAR-1 which belongs to the group of Al-Mg-Si alloys. The influence of the heat treatment on structure of the alloy as well as on the mechanical and corrosion properties was studying. In the paper the results of some properties of PAR-1 alloy after irradiation were done. (author). 27 refs, 43 figs, 9 tabs.

  7. Properties of the Aluminium Alloy EN AC-51100 after Laser Surface Treatment

    Directory of Open Access Journals (Sweden)

    Tański T.

    2016-03-01

    Full Text Available In this paper, the influence of a laser surface treatment on the structure and properties of aluminium alloy has been determined. The aim of this work was to improve the tribological properties of the surface layer of the EN AC-51100 aluminium alloy by simultaneously melting and feeding silicon carbide particles into the molten pool. The silicon carbide powder was introduced into the liquid metal using a gravity feeder within a constant feed rate of 1 g/min. A high power diode laser (HPDL was used for remelting. Laser beam energies used in experiments were 1.8 kW, 2.0 kW and 2.2 kW, combined with the constant velocity of 50 mm/min. As a result of the laser treatment on the aluminium alloy, a composite layer with greater hardness and wear resistance compared to the based material was obtained.

  8. Void growth in high strength aluminium alloy single crystals: a CPFEM based study

    Science.gov (United States)

    Asim, Umair; Siddiq, M. Amir; Demiral, Murat

    2017-04-01

    High strength aluminium alloys that are produced through forming and joining processes are widely used in aerospace components. The ductile failure in these metals occurs due to the evolution and accumulation of microscopic defects, such as microvoids and shear bands. The present work investigates the underlying physical mechanisms during ductile failure by performing a rigorous, fully-validated, three-dimensional crystal plasticity, finite element study with aluminium alloy single crystals. Representative volume element (RVE) based simulations of single crystalline aluminium alloys (AA-5xxx) with different void geometries and orientations have been performed. Both local and nonlocal crystal plasticity constitutive models have been implemented in a finite element framework and are used to seek new insights into the interrelationships among void growth, initial porosity, initial void size, plastic anisotropy, and local/nonlocal size effects.

  9. Process parameters optimization for friction stir welding of RDE-40 aluminium alloy using Taguchi technique

    Institute of Scientific and Technical Information of China (English)

    A.K.LAKSHMINARAYANAN; V.BALASUBRAMANIAN

    2008-01-01

    Taguchi approach was applied to determine the most influential control factors which will yield better tensile strength of the joints of friction stir welded RDE-40 aluminium alloy. In order to evaluate the effect of process parameters such as tool rotational speed, traverse speed and axial force on tensile strength of friction stir welded RDE-40 aluminium alloy, Taguchi parametric design and optimization approach was used. Through the Taguchi parametric design approach, the optimum levels of process parameters were determined. The results indicate that the rotational speed, welding speed and axial force are the significant parameters in deciding the tensile strength of the joint. The predicted optimal value of tensile strength of friction stir welded RDE-40 aluminium alloy is 303 MPa. The results were confirmed by further experiments.

  10. The effect of heat treatment on the corrosion behaviour of 319 aluminium alloy

    Energy Technology Data Exchange (ETDEWEB)

    Panagopoulos, C.N.; Georgiou, E.P.; Giannakopoulos, K.I. [Laboratory of Physical Metallurgy, National Technical University of Athens, Zografos, Athens (Greece)

    2009-06-15

    The effect of various heat treatments on the corrosion behaviour of 319 T1 cast aluminium alloy was investigated. From this alloy, specimens were heat treated in T5, T6 and two steps solution heat treatment T6 conditions and afterwards were subjected to electrochemical corrosion in a 0.1 M NaCl solution (pH = 12). From the above treatments, T5 heat treatment did not improve the corrosion resistance of the as-received alloy in contrast to T6 heat treatment which improved the corrosion resistance of the same alloy. However, two steps solutionizing T6 treatment showed the best corrosion resistance of the aluminium alloy. (Abstract Copyright [2009], Wiley Periodicals, Inc.)

  11. Effect of welding current and voltage on the mechanical properties of wrought (6063 aluminium alloy

    Directory of Open Access Journals (Sweden)

    Oladele Isiaka Oluwole

    2010-06-01

    Full Text Available This work was carried out to investigate the effect of welded joints on the mechanical properties of wrought (6063 aluminium alloy. The study revealed the influence of current and voltage on the welded joint as well as the mechanical properties of the alloy. The alloy samples were welded together by metal inert gas welding process at varying values of current and voltage after which mechanical tests were performed on the welded samples. The microstructural examination of the various fusion zones obtained was carried out. Appreciable variations in the properties of the welded samples were observed due to changes in the microstructural features of the alloys. It was concluded that variation of current and voltage remarkably affect the mechanical properties of the wrought 6063 Aluminium alloy. As the voltage increases from 25 to 30 V, the ultimate tensile strengths and hardness values increases while the impact strengths decreases but the current did not show such trend.

  12. Impact Behavior of A356 Foundry Alloys in the Presence of Trace Elements Ni and V

    Science.gov (United States)

    Casari, Daniele; Ludwig, Thomas H.; Merlin, Mattia; Arnberg, Lars; Garagnani, Gian Luca

    2015-02-01

    In the present work, the impact behavior of unmodified A356 alloys with the addition of Ni or V in as-cast and T6 heat-treated conditions was assessed. Charpy V-notched specimens obtained from sand and permanent mold casting showed low total absorbed energy average values ( W t permanent mold cast alloys due to the locally finer microstructure. Concurrent mechanisms related to the chemical composition, solidification conditions and heat treatment were found to control the impact properties of the alloys. While the trace element Ni exerted only minor effects on the impact toughness of the A356 alloy, V had a strong influence: (i) V-containing sand cast alloys absorbed slightly higher impact energies compared to the corresponding A356 base alloys; (ii) in the permanent mold cast alloys, V in solid solution led to a considerable loss of ductility, which in turn decreased the total absorbed energy.

  13. MICROSTRUCTURAL AND MECHANICAL STUDY OF ALUMINIUM ALLOYS SUBMITTED TO DISTINCT SOAKING TIMES DURING SOLUTION HEAT TREATMENT

    Directory of Open Access Journals (Sweden)

    Valmir Martins Monteiro

    2014-12-01

    Full Text Available This work studies the microstructural characteristics and mechanical properties for different aluminium alloys (1100, 3104 and 8011 hot rolled sheets that were subjected to a solution heat treatment with distinct soaking times, in order to promote microstructural and mechanical changes on these alloys with solute fractions slightly above the maximum solubility limit. Scanning Electronic Microscopy (SEM / Energy Dispersive Spectroscopy X-Ray (EDS, X-Ray Diffraction (XRD and Hardness Tests were employed to observe the microstructural / compositional and mechanical evaluation. For the 1100 and 8011 alloys the more suitable soaking time occur between 1 and 2 hours, and for the 3104 alloy occurs between 2 and 3 hours.

  14. Galvanic corrosion of rare earth modified AM50 and AZ91D magnesium alloys coupled to steel and aluminium alloys

    Energy Technology Data Exchange (ETDEWEB)

    Mohedano, M.; Arrabal, R.; Pardo, A.; Paucar, A.; Merino, M. C.; Matykina, E.; Mingo, B.; Garces, G.

    2014-04-01

    Electrochemical and gravimetric measurements were used to examine the effects of neodymium and gadolinium additions on the galvanic corrosion behaviour of AM50 and AZ91D magnesium alloys coupled to A 570 Gr 36 carbon steel and AA2011-AA6082 aluminium alloys. Rare earth modified alloys showed Al{sub 2}Nd/Al{sub 2}Gd and Al-Mn-Nd/Al-Mn-Gd intermetallics, reduced area fraction of {beta}-Mg{sub 1}7Al{sub 1}2 phase and increased corrosion resistance due to increased surface passivity and suppression of micro-galvanic couples. Neodymium and gadolinium additions improved the galvanic corrosion resistance of AM50 alloy, but were less effective in case of the AZ91D alloy. The AA6082 alloy was the most compatible material and the AA2011 alloy was the least compatible. (Author)

  15. Steam assisted oxide growth on aluminium alloys using oxidative chemistries: Part II corrosion performance

    Science.gov (United States)

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

    2015-11-01

    Surface treatment of aluminium alloys using steam with oxidative chemistries, namely KMnO4 and HNO3 resulted in accelerated growth of oxide on aluminium alloys. Detailed investigation of the corrosion performance of the treated surfaces was carried out using potentiodynamic polarisation and standard industrial test methods such as acetic acid salt spray (AASS) and filiform corrosion on commercial AA6060 alloy. Barrier properties of the film including adhesion were evaluated using tape test under wet and dry conditions. Electrochemical results showed reduced cathodic and anodic activity, while the protection provided by steam treatment with HNO3 was a function of the concentration of NO3- ions. The coating generated by inclusion of KMnO4 showed highest resistance to filiform corrosion. Overall, the performance of the steam treated surfaces under filiform corrosion and AASS test was a result of the local coverage of the alloy microstructure resulting from steam containing with KMnO4 and HNO3.

  16. Recovery of actinides from actinide-aluminium alloys by chlorination: Part II

    Science.gov (United States)

    Souček, P.; Cassayre, L.; Eloirdi, R.; Malmbeck, R.; Meier, R.; Nourry, C.; Claux, B.; Glatz, J.-P.

    2014-04-01

    A chlorination route is being investigated for recovery of actinides from actinide-aluminium alloys, which originate from pyrochemical recovery of actinides from spent metallic nuclear fuel by electrochemical methods in molten LiCl-KCl. In the present work, the most important steps of this route were experimentally tested using U-Pu-Al alloy prepared by electrodeposition of U and Pu on solid aluminium plate electrodes. The investigated processes were vacuum distillation for removal of the salt adhered on the electrode, chlorination of the alloy by chlorine gas and sublimation of the AlCl3 formed. The processes parameters were set on the base of a previous thermochemical study and an experimental work using pure UAl3 alloy. The present experimental results indicated high efficiency of salt distillation and chlorination steps, while the sublimation step should be further optimised.

  17. 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.

  18. Development of Al-TiC Alloys Using Powder Metallurgy as Grain Refiners for Aluminium and Its Alloys

    Directory of Open Access Journals (Sweden)

    Abdel-Nasser .M. Omran

    2014-07-01

    Full Text Available Al-Ti-C master alloys have been widely investigated for many years as grain refiner for aluminium and its alloys. In this work, the Al-Ti-C master alloys are synthesized using powder metallurgy technique through the mixing of aluminium and TiC powders with different TiC contents 3.75 (3, 5(4, 6.25(5 and 7.5(6 Wt% TiC(Wt% Ti. The mixing powders with different contents of TiC were pressed in cylinder shape. The pressed specimens were sintered from 450 oC in a tube furnace under argon atmosphere for 2 hrs. The produced alloys before and after sintering are examined using SEM, EDX and XRD. The results indicate that, the Al-TiC alloy containing fine TiC particles dispersed in all matrix was successfully prepared. The prepared Al-TiC alloys with different contents of TiC were evaluated using the KBI test mold as grain refiner for pure aluminum and its alloys. The results indicate that the prepared Al-TiC master alloy is high grain refining efficiency for pure aluminum and its alloys.

  19. Interface and microstructure characteristics of SiCp/2024 aluminium alloy composite

    Institute of Scientific and Technical Information of China (English)

    罗守靖; 姜巨福; 王迎; 藤东东; 祖丽君

    2003-01-01

    Electron microscope examination of the microstructure, interface and fracture surface of SiC particulatereinforced 2024 aluminium alloy composites produced by powder mixing and semi-solid extrusion process was pres-ented. The microstructure of SiCp/2024 composites fabricated by the present method is characterized by uniformlydistributed SiC particulates in well-densified matrix. Conventional transmission electron microscopy(TEM) revealsthe interface between the SiC particulates and the aluminium matrix. It is shown that this interface provides verystrong bonding which is further evidenced by the fractographic results, and that there is no apparent chemical reac-tion. Examination of the fracture surface indicates that the bonding strength between the SiC particulates and the a-luminium alloy matrix is stronger than that of the matrix. The dimples and tearing edges on the fracture surface ofcomposites are obviously observed.

  20. Surface Chemistry of Aluminium Alloy Slid against Steel Lubricated by Organic Friction Modifier in Hydrocarbon Oil

    Directory of Open Access Journals (Sweden)

    Ichiro Minami

    2012-01-01

    Full Text Available The lubrication mechanism of aluminium alloy slid against steel was investigated from the standpoint of surface chemistry. Low friction and low wear were observed using glycerol mono-olate in a hydrocarbon as lubricant. Increase in the silicon content in the aluminium alloy during rubbing was observed by surface analyses using (1 Auger electron spectroscopy, (2 scanning electron microscopy along with energy dispersive X-ray spectroscopy, and (3 X-ray photoelectron spectroscopy. Mild removal of the passive state (aluminium oxide from the uppermost surface by the additive during the running-in process was proposed as the lubrication mechanism. The importance of additive chemistry that improves the running-in process was pointed out.

  1. INVESTIGATION OF ECOLOGICAL SAFETY OF LUBRICATIONS FOR CASTING UNDER PRESSURE OF ALUMINIUM ALLOYS

    Directory of Open Access Journals (Sweden)

    A. M. Mihaltsov

    2008-01-01

    Full Text Available The investigations of environmental safety of different lubrications for moulds for casting under pressure of aluminium alloys are carried out. The method of carrying out of experiments on determination of harmful substances, escaping from lubrication in the process of destruction, is described.

  2. Improvement of hardness of aluminium AA1200 by laser surface alloying

    CSIR Research Space (South Africa)

    Mabhali, Luyolo AB

    2010-07-01

    Full Text Available Aluminium is vastly used in industry due to its low cost, light weight and excellent workability, but lacks in wear resistance and hardness. Laser alloying is used to improve the surface properties such as hardness by modifying the composition...

  3. Laser assisted cold spraying of aluminium alloy powder on stainless steel substrate

    CSIR Research Space (South Africa)

    Tlotleng, Monnamme

    2012-12-01

    Full Text Available International Conference on Information Warfare and Security, Denver, USA 25-26 March 2013 LASER ASSISTED COLD SPRAYING OF ALUMINIUM ALLOY POWDER ON STAINLESS STEEL SUBSTRATE M. Tlotleng1, 2; E.O. Olakanmi2; C. Meacock; Sisa Pityana1, 3; E.T. Akinlabi2...

  4. Laser welding of SSM Cast A356 aluminium alloy processed with CSIR-Rheo technology

    CSIR Research Space (South Africa)

    Akhter, R

    2006-01-01

    Full Text Available Samples of aluminium alloy A356 were manufactured by Semi Solid Metals HPDC technology, developed recently in CSIR, Pretoria. They were butt welded in as cast conditions using as Nd: YAG laser. The best metal and weld microstructure were presented...

  5. Laser surface alloying of aluminium with WC+Co+NiCr for improved wear resistance

    CSIR Research Space (South Africa)

    Nath, S

    2012-03-01

    Full Text Available In the present study, laser surface alloying of aluminium with WC + Co + NiCr (in the ratio of 70:15:15) has been conducted using a 5 kW continuous wave (CW) Nd:YAG laser (at a beam diameter of 0.003 m), with the output power ranging from 3 to 3.5 k...

  6. Characterization of steam generated anti-corrosive oxide films on Aluminium alloys

    DEFF Research Database (Denmark)

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

    2014-01-01

    alloy surfaces were exposed to high pressure steam produced by an autoclave at a temperature of 107 – 121 °C and pressure of 15 -17 psi for 10 minutes to produce a thin coating of aluminium oxide. The aim of this study is to understand the effect of high pressure steam with and without different...

  7. Reducing non value adding aluminium alloy in production of parts through high pressure die casting

    CSIR Research Space (South Africa)

    Pereira, MFVT

    2010-10-01

    Full Text Available The difficulties and issues associated with the economics of the process and die life in casting Aluminium alloys, as experienced by the high pressure die casting industry, were reasons behind undertaking this research project. The use of a tungsten...

  8. Steam assisted oxide growth on aluminium alloys using oxidative chemistries: Part I Microstructural investigation

    DEFF Research Database (Denmark)

    Din, Rameez Ud; Piotrowska, Kamila; Gudla, Visweswara Chakravarthy;

    2015-01-01

    The surface treatment of aluminium alloys under steam containing KMnO4 and HNO3resulted in the formation of an oxide layer having a thickness of up to 825 nm. The use of KMnO4 and HNO3 in the steam resulted in incorporation of the respective chemical species into the oxide layer. Steam treatment ...

  9. Corrosion behaviour of 6063 aluminium alloy in acidic and in alkaline media

    Directory of Open Access Journals (Sweden)

    Prabhu Deepa

    2017-05-01

    Full Text Available The corrosion behaviour of 6063 aluminium alloy was investigated in different concentrations of phosphoric acid medium and sodium hydroxide medium at different temperatures. The study was done by electrochemical method, using Tafel polarization technique and electrochemical impedance spectroscopy (EIS technique. The surface morphology was investigated using scanning electron microscope (SEM with Energy-dispersive X-ray spectroscopy (EDX. The results showed that the 6063 aluminium alloy undergoes severe corrosion in sodium hydroxide medium than in phosphoric acid medium. The corrosion rate of 6063 aluminium alloy increased with an increase in the concentration of acid as well as with alkali. The corrosion rate was increased with an increase in temperature. The kinetic parameters and thermodynamic parameters were calculated using Arrhenius theory and transition state theory. Suitable mechanism was proposed for the corrosion of 6063 aluminium alloy in phosphoric acid medium and sodium hydroxide medium. The results obtained by Tafel polarization and electrochemical impedance spectroscopy (EIS techniques were in good agreement with each other.

  10. Effect of Pulsed Current TIG Welding Parameters on Pitting Corrosion Behaviour of AA6061 Aluminium Alloy

    Institute of Scientific and Technical Information of China (English)

    T. Senthil Kumar; V. Balasubramanian; M. Y. Sanavullah; S. Babu

    2007-01-01

    Medium strength aluminium alloy (Al-Mg-Si alloy) has gathered wide acceptance in the fabrication of light weight structures requiring a high strength-to weight ratio, such as transportable bridge girders, military vehicles, road tankers and railway transport systems. The preferred welding process for aluminium alloy is frequently TIG (tungsten inert gas) welding due to its comparatively easier applicability and better economy.In the case of single pass TIG welding of thinner section of this alloy, the pulsed current has been found beneficial due to its advantages over the conventional continuous current process. The use of pulsed current parameters has been found to improve the mechanical properties of the welds compared to those of continuous current welds of this alloy due to grain refinement occurring in the fusion zone. A mathematical model has been developed to predict pitting corrosion potential of pulsed current TIG welded AA6061 aluminium alloy.Factorial experimental design has been used to optimize the experimental conditions. Analysis of variance technique has been used to find out the significant pulsed current parameters. Regression analysis has been used to develop the model. Using the developed model pitting corrosion potential values have been estimated for different combinations of pulsed current parameters and the results are analyzed in detail.

  11. Radiation resistance and parameters of activation of aluminium-magnesium-scandium and aluminium-magnesium-vanadium alloys under neutron irradiation

    Science.gov (United States)

    Ivanov, L. I.; Ivanov, V. V.; Lazorenko, V. M.; Platov, Yu. M.; Tovtin, V. I.; Toropova, L. S.

    1992-09-01

    Alloys Al2.24Mg0.23Sc0.04Zr, Al2.24Mg0.12Sc0.04Zr, and Al2.24Mg0.05V (at.)) annealed at 150°C and 400°C were irradiated ≈70 and ≈150°C in the SM-2 reactor. The maximum neutron fluence was 4.7×1024 m-2 (E > 0.1 MeV). The tensile tests were carried out in the temperature range 20 to 350°C. Alloy Al2.24Mg0.23Sc0.04Zr annealed at 400°C and alloy Al2.24Mg0.12Sc0.04Zr annealed at 150°C at all test temperature, retained good mechanical properties after irradiation. The mechanisms for the radiation resistance of aluminiumscandium and aluminiummagnesiumscandium alloys are discussed. Calculations of induced radioactivity and its decay behaviour after shutdown in aluminium and Al2.24Mg(0.12-0.23)Sc alloys were carried out. Composition of the radionuclides in these materials after irradiation in the SM-2 reactor were also determined using a gamma-spectroscopy technique.

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

    Directory of Open Access Journals (Sweden)

    A. Zyska

    2011-07-01

    Full Text Available 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 advantageous set of the examined properties is exhibited by the alloys containing over 2.5% Si. They are characterised by higher parameters as compared with the standardised alloy. Observations of microstructures reveal that silicon precipitates as a separate compact phase, and its morphology depends on t he Si content in the alloy. The performed examinations show that silicon can satisfactorily replace copper in high aluminium Zn alloys, thus eliminating the problem of dimensional instability of castings.

  13. Recovery of actinides from actinide-aluminium alloys by chlorination: Part I

    Science.gov (United States)

    Cassayre, L.; Souček, P.; Mendes, E.; Malmbeck, R.; Nourry, C.; Eloirdi, R.; Glatz, J.-P.

    2011-07-01

    Pyrochemical processes in molten LiCl-KCl are being developed in ITU for recovery of actinides from spent nuclear fuel. The fuel is anodically dissolved to the molten salt electrolyte and actinides are electrochemically reduced on solid aluminium cathodes forming solid actinide-aluminium alloys. A chlorination route is being investigated for recovery of actinides from the alloys. This route consists in three steps: Vacuum distillation for removal of the salt adhered on the electrode, chlorination of the actinide-aluminium alloys by chlorine gas and sublimation of the formed AlCl 3. A thermochemical study showed thermodynamic feasibility of all three steps. On the basis of the conditions identified by the calculations, experiments using pure UAl 3 alloy were carried out to evaluate and optimise the chlorination step. The work was focused on determination of the optimal temperature and Cl 2/UAl 3 molar ratio, providing complete chlorination of the alloy without formation of volatile UCl 5 and UCl 6. The results showed high efficient chlorination at a temperature of 150 °C.

  14. Identification of monoclinic θ-phase dispersoids in a 6061 aluminium alloy

    Science.gov (United States)

    Buchanan, Karl; Ribis, Joël; Garnier, Jérôme; Colas, Kimberly

    2016-04-01

    Intermetallic dispersoids play an important role in controlling the 6xxx alloy series' grain distribution and increasing the alloy's toughness. The dispersoid distribution in a 6061 aluminium alloy (Al-Mg-Si) was analysed by transmission electron microscopy, selected area diffraction and energy-dispersive X-ray spectroscopy. The dispersoids had three unique crystal structures: simple cubic ?, body-centred cubic ? and monoclinic (C2/m). While the SC and BCC dispersoids have been well characterized in the literature, a detailed analysis of monoclinic dispersoids has not been presented. Therefore, the current work discusses the chemical composition, crystal structure and morphology of the monoclinic dispersoids.

  15. Diamond turning and polishing tests on new RSP aluminium alloys

    NARCIS (Netherlands)

    Horst, R. ter; Haan, M. de; Gubbels, G.P.H.; Senden, R.; Venrooy, B.W.H. van; Hoogstrate, A.M.

    2012-01-01

    For years now conventional aluminium 6061 T6 has widely been used for mirrors in astronomical instruments, being diamond turned or since a few years also being optically polished. This allows the development of optical systems that can be tested and operated at any temperature, without being affecte

  16. Cavitation-aided grain refinement in aluminium alloys

    NARCIS (Netherlands)

    Atamanenko, T.V.

    2010-01-01

    This thesis deals with grain refinement under the influence of ultrasonic-driven cavitation in aluminium casting processes. Three major goals of this research were: (1) to identify the mechanism of the cavitation-aided grain refinement at different stages of solidification; (2) to reveal the

  17. Cavitation-aided grain refinement in aluminium alloys

    NARCIS (Netherlands)

    Atamanenko, T.V.

    2010-01-01

    This thesis deals with grain refinement under the influence of ultrasonic-driven cavitation in aluminium casting processes. Three major goals of this research were: (1) to identify the mechanism of the cavitation-aided grain refinement at different stages of solidification; (2) to reveal the conditi

  18. Gating System Design for Casting thin Aluminium Alloy (Al-Si) Plates

    OpenAIRE

    Victor ANJO; Reyaz KHAN

    2013-01-01

    The main problems caused by improper gating are entrained aluminium oxide films, cuts and washes, low casting yield and entrapped gas. This study describes the design of a gating system to produce thin Aluminium cast alloy plates of different sizes and thicknesses of 4mm, 6mm, 8mm, and 10mm using the non-pressurized gating with ratio of 1:4:4 and green sand moulding technique. The gating design was based on the laws of fluid mechanics and empirical rules of gating for non ferrous metals. The ...

  19. INVESTIGATION OF POWDER-GAS EMISSIONS, FONNED AT MELTING AND REFINING OF ALUMINIUM ALLOYS IN REVERBERATING FURNACES

    Directory of Open Access Journals (Sweden)

    S. P. Zadrutskij

    2009-01-01

    Full Text Available As a result of carried out analysis of processes of aluminium alloys casting and refining in reverberating  furnaces it is determined that searching source of harmful emissions are the refining processes.

  20. 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

  1. Strength properties examination of high zinc aluminium alloys inoculated with Ti addition

    Directory of Open Access Journals (Sweden)

    J. Buras

    2017-05-01

    Full Text Available This paper includes studies on the influence of grain refinement treatment with respect to the composition and structure of high zinc aluminium casting alloys on the changes of their tensile properties. The Al-20wt.%Zn alloy was inoculated with master alloys AlTi5B1 and AlTi3C0.15 to determine the impact of a variable titanium addition on the tensile properties of AlZn20 alloy, and determine on this basis an optimal addition of Ti that would ensure the improvement of elongation of alloys cast in the sand mould, at the same time maintaining high tensile strength. Within the studies, light microscopy (LM and strength tests were applied. Experimental results showed that the inoculation of high zinc aluminium alloy AlZn20 with the master alloys AlTi5B1 and AlTi3C0.15 causes intensive structure refinement, while the intensity of reaction of both master alloys is comparable. The AlTi3C0.15 master alloy addition, selected for further studies, introducing about 100 ppm Ti, enhances the tensile properties of the alloy; the elongation increases about 20% and tensile strength increases about 10% against the initial values (uninoculated alloy. Further increase of the Ti addition up to 500?00 ppm leads to the 搊ver-inoculation?effect that is accompanied by the decrease of elongation. Therefore,the Ti addition should be reduced to the level of about 100 ppm which ensures obtaining a set of optimal properties.

  2. Impact toughness improvement of high strength aluminium alloy by intrinsic and extrinsic fracture mechanisms via hot roll bonding

    OpenAIRE

    Cepeda-Jiménez, C.M.; García-Infanta, J.M.; Pozuelo, M.; Ruano, Oscar Antonio; Carreño, Fernando

    2009-01-01

    A multilayer aluminium laminate comprising ten layers of Al-Zn-Mg-Cu alloy (82 vol.%) and nine layers of pure aluminium (18 vol.%) has been processed by hot rolling. The rolled laminate was characterized by electron backscattering diffraction, Charpy impact and shear tests. The multilayer laminate showed an outstanding Charpy impact toughness, being eighteen times higher than that for the as-received Al-Zn-Mg-Cu alloy. Damage tolerance improvement was due to the high volume fra...

  3. Laser beam welding of high strength aluminium-lithium alloys; Laserstrahlschweissen von hochfesten Aluminium-Lithium Legierungen

    Energy Technology Data Exchange (ETDEWEB)

    Enz, Josephin

    2012-07-01

    The present development in aircraft industry determined by the demand for a higher cost-effectiveness. Laser beam welding is one of the most promising joining technologies for the application in the aircraft industry through the considerable reduction of the production costs. Furthermore the weight of an aircraft structure can be reduced by the use of light and high strength aluminium alloys. This paper deals with the development of a process for the laser beam welding of a skin-stringer-joint where the Al-Li-alloy AA2196 is used as stringer material and the Al-Li-alloy AA2198 is used as skin and stringer material. By the use of design of experiments the optimal welding process parameters for different material combinations were determined which will be used for the welding of a 5-stringer panel. Therefore the weld seams of the joints were tested for irregularities and microstructural characteristics. In addition several mechanical tests were performed, which define the quality of the welded joint. Furthermore the influence of the oxide layer and the welding preparation on the welding performance was investigated. (orig.) [German] Die derzeitigen Entwicklungen im Flugzeugbau werden durch die allgemeine Forderung nach einer Steigerung der Wirtschaftlichkeit bestimmt. Das Laserstrahlschweissen ist dabei eines der vielversprechendsten Fuegeverfahren fuer die Anwendung im Flugzeugbau durch das die Herstellungskosten deutlich reduziert werden koennen. Zudem kann durch die Verwendung von leichten und hochfesten Aluminium-Legierungen das Gewicht einer Flugzeugstruktur zusaetzlich reduziert werden. Die vorliegende Arbeit befasst sich mit der Entwicklung eines Prozesses zum Laserstrahlschweissen einer Skin-Stringer-Verbindung aus den Aluminium-Lithium-Legierungen AA2196 (als Stringer-Werkstoff) und AA2198 (als Skin- und Stringer-Werkstoff). Unter Verwendung der statistischen Versuchsplanung wurden die optimalen Einstellungen der Schweissprozessparameter fuer die

  4. Steam assisted oxide growth on aluminium alloys using oxidative chemistries: Part I Microstructural investigation

    Science.gov (United States)

    Din, Rameez Ud; Piotrowska, Kamila; Gudla, Visweswara Chakravarthy; Jellesen, Morten Stendahl; Ambat, Rajan

    2015-11-01

    The surface treatment of aluminium alloys under steam containing KMnO4 and HNO3 resulted in the formation of an oxide layer having a thickness of up to 825 nm. The use of KMnO4 and HNO3 in the steam resulted in incorporation of the respective chemical species into the oxide layer. Steam treatment with solution containing HNO3 caused dissolution of Cu and Si from the intermetallic particles in the aluminium substrate. The growth rate of oxide layer was observed to be a function of MnO4- and NO3- ions present in the aqueous solution. The NO3- ions exhibit higher affinity towards the intermetallic particles resulting in poor coverage by the steam generated oxide layer compared to the coating formed using MnO4- ions. Further, increase in the concentration of NO3- ions in the solution retards precipitation of the steam generated aluminium hydroxide layer.

  5. BEHAVIOUR OF COPPER AND ALUMINIUM ELECTRODES ON EDM OF EN-8 ALLOY STEEL

    Directory of Open Access Journals (Sweden)

    DHANANJAY PRADHAN

    2011-07-01

    Full Text Available Electrical discharge machining (EDM has been recognized as an efficient production method for precision machining of electrically conducting hardened materials. Copper and aluminium are used as electrode materials in this process with Kerosene oil as the dielectric medium. In this work, the behavior of copper and aluminium electrodes on electric discharge machining of EN-8 alloy steel had been studied. Keeping all other machining parameters same, the hardened work material was machined with the two electrodes at different values of peak current, pulse-on time & duty factor according to 23 full factorial design. It has been found that copper shows better results than aluminium in term of surface finish (μm in same dielectric media. Therefore, copper is recommended as a good electrode material.

  6. Accelerated growth of oxide film on aluminium alloys under steam: Part I: Effects of alloy chemistry and steam vapour pressure on microstructure

    DEFF Research Database (Denmark)

    Din, Rameez Ud; Gudla, Visweswara C.; Jellesen, Morten S.;

    2015-01-01

    at the top. The kinetics of formation of film understeamwas rapid; approx. 350nm thick layers were generated within 5 s of steam treatment, however increase in thickness of the oxide retarded further growth. The enrichment or depletion of different alloying elements at the surface of aluminium as a result...... of alkaline etching pre-treatment influenced the thickness and growth of theoxide. Moreover the steam treatment resulted in the partial oxidation of second phase intermetallic particles present in the aluminium alloy microstructure....

  7. Evaluating the Tensile Properties of Aluminum Foundry Alloys through Reference Castings—A Review

    Science.gov (United States)

    Anilchandra, A.R.; Arnberg, Lars; Bonollo, Franco; Fiorese, Elena

    2017-01-01

    The tensile properties of an alloy can be exploited if detrimental defects and imperfections of the casting are minimized and the microstructural characteristics are optimized through several strategies that involve die design, process management and metal treatments. This paper presents an analysis and comparison of the salient characteristics of the reference dies proposed in the literature, both in the field of pressure and gravity die-casting. The specimens produced with these reference dies, called separately poured specimens, are effective tools for the evaluation and comparison of the tensile and physical behaviors of Al-Si casting alloys. Some of the findings of the present paper have been recently developed in the frame of the European StaCast project whose results are complemented here with some more recent outcomes and a comprehensive analysis and discussion. PMID:28867796

  8. Visual sensing of weld pool in variable polarity TIG welding of aluminium alloy

    Institute of Scientific and Technical Information of China (English)

    ZHANG Guang-jun; YAN Zhi-hong; WU Lin

    2006-01-01

    The passive visual sensing method was successfully applied to monitor the weld pool in TIG welding of aluminium alloy.In order to reduce the disturbance from the arc and acquire clear image, two techniques were used: one was the own-developed computer-controlled variable polarity power(VPP), the other was the composite filter technology. The VPP source did not have high-frequency electromagnetic interference from arc stabilizer in traditional AC welding power, and its output current wave was controlled by computer, so the imaging current and the imaging time could be adjusted easily. Filter spectral window was identified at 650 nm by analyzing the measured arc light spectral distribution. At the end, the high quality and clear images of welding pool of aluminium alloy were successfully acquired at low imaging current.

  9. Braze Welding TIG of Titanium and Aluminium Alloy Type Al – Mg

    Directory of Open Access Journals (Sweden)

    Winiowski A.

    2016-03-01

    Full Text Available The article presents the course and the results of technological tests related to TIG-based arc braze welding of titanium and AW-5754 (AlMg3 aluminium alloy. The tests involved the use of an aluminium filler metal (Al99.5 and two filler metals based on Al-Si alloys (AlSi5 and AlSi12. Braze welded joints underwent tensile tests, metallographic examinations using a light microscope as well as structural examinations involving the use of a scanning electron microscope and an X-ray energy dispersive spectrometer (EDS. The highest strength and quality of welds was obtained when the Al99.5 filler metal was used in a braze welding process. The tests enabled the development of the most convenient braze welding conditions and parameters.

  10. RESEARCH OF FATIGUE AND MECHANICAL PROPERTIES AlMg1SiCu ALUMINIUM ALLOYS

    Directory of Open Access Journals (Sweden)

    Mária Mihaliková

    2015-11-01

    Full Text Available The paper is concerned with an analysis of utility and fatigue properties of industrially produced aluminium alloy, specifically EN AW 6061 (AlMg1SiCu, reinforced with the particles of SiC. The following properties were subject to evaluation: microstructure and sub-structure, mechanical characteristics. All of these mechanical properties in pre- and post- equal channel angular pressed (ECAP state have been studied. The hardness was evaluated by Vickers hardness test at the load of HV10. The significant part the thesis was devoted to the fatigue properties at cyclic load in torsion. The presented results demonstrate well that the combination of fractography and microscopy can give a significant contribution to the knowledge of initiation and propagation crack in the aluminium alloy.

  11. Effect of Process Parameters of Friction Stir Welded Joint for Similar Aluminium Alloys H30

    Directory of Open Access Journals (Sweden)

    Vanita S. Thete

    2015-05-01

    Full Text Available In this paper the effect of process parameters of friction stir welded joint for similar aluminium alloys H30 was studied. Taper cylindrical with three flutes all made of High speed steel was used for the friction stir welding (FSW aluminium alloy H30 and the tensile test of the welded joint were tested by universal testing method. The optimization done using detailed mathematical model is simulated by Minitab17. In this investigation, an effective approach based on Taguchi method, has been developed to determine the optimum conditions leading to higher tensile strength. Experiments were conducted on varying rotational speed, transverse speed, and axial force using L9 orthogonal array of Taguchi method. The present study aims at optimizing process parameters to achieve high tensile strength.

  12. Composite Ni-Co-fly ash coatings on 5083 aluminium alloy

    Energy Technology Data Exchange (ETDEWEB)

    Panagopoulos, C.N., E-mail: chpanag@metal.ntua.gr [Laboratory of Physical Metallurgy, National Technical University of Athens, Zografos, 15780 Athens (Greece); Georgiou, E.P.; Tsopani, A.; Piperi, L. [Laboratory of Physical Metallurgy, National Technical University of Athens, Zografos, 15780 Athens (Greece)

    2011-03-15

    Ni-Co-fly ash coatings were deposited on zincate treated 5083 wrought aluminium alloy substrates with the aid of the electrodeposition technique. Structural and chemical characterization of the produced composite 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-Co-fly ash coatings were found to consist of a crystalline Ni-Co solid solution with dispersed fly ash particles. In addition, chemical analysis of the Ni-Co matrix showed that it consisted of 80 wt.% Ni and 20 wt.% Co. The co-deposition of fly ash particles leads to a significant increase of the microhardness of the coating. The corrosion behaviour of the Ni-Co-fly ash/zincate coated aluminium alloy, in a 0.3 M NaCl solution (pH = 3.5), was studied by means of potentiodynamic corrosion experiments.

  13. Fatigue damage rule of LY12CZ aluminium alloy under sequential biaxial loading

    Science.gov (United States)

    Wang, YingYu; Zhang, DaChuan; Yao, WeiXing

    2014-01-01

    A series of biaxial two-level variable amplitude loading tests are conducted on smooth tubular specimens of LY12CZ aluminium alloy. The loading paths of 90° out-of-phase, 45° out-of-phase and 45° in-phase are utilized. The fatigue damage cumulative rules under two-level step loading of three loading paths are analyzed. By introducing a parameter α which is a function of the phase lag angle between the axial and the torsional loading, a new multiaxial nonlinear fatigue damage cumulative model is proposed. The proposed model is evaluated by the experimental data for two-level loading, multi-level loading of LY12CZ aluminium alloy, and multi-level loading of 45 steel. Fatigue lives predicted are within a factor of 2 scatter band.

  14. Fundiciones aleadas para piezas de repuesto. // Alloy foundries for spare parts.

    Directory of Open Access Journals (Sweden)

    J. Hernández de la Torre

    2003-09-01

    Full Text Available En el presente trabajo se aborda la concepción de mejorar las piezas mediante el análisis cuidadoso de las propiedades quelas mismas deben poseer, para responder a las severas exigencias del trabajo y en base a ello seleccionar la aleación y lasvías para mejorar sus cualidades y por ende su durabilidad. Como vías, en el caso de las fundiciones, se seleccionan laaleación en la carga y la modificación en la cazuela; en ambos casos con elementos aleantes que influyen sobre la matrizmetálica y la forma, tamaño y distribución del grafito. Se ejemplifica en base a piezas, como cuchillas centrales paramolinos azucareros.Palabras claves: fundición gris aleada, matriz metálica, grafito, cuchillas centrales._________________________________________________________________________________Abstract:This paper deals with the improvement of spare parts by means of a careful analysis of their properties, to face the hardexploitation conditions. Based on this analysis, the type of alloy and the ways to improve its properties and durability arefound. Two ways were applied for cast iron; the addition of alloy elements in the charge and the modification of moltenmetal in the ladle. In both cases, alloy elements are used to influence on the metallic matrix and the graphite distribution,size and form. The research is applied in spare parts such as central knives for sugar mills.Key words: alloy gray cast iron, metallic matrix, graphite, central knifes.

  15. Heat input effect of friction stir welding on aluminium alloy AA 6061-T6 welded joint

    Directory of Open Access Journals (Sweden)

    Sedmak Aleksandar

    2016-01-01

    Full Text Available This paper deals with the heat input and maximum temperature developed during friction stir welding with different parameters. Aluminium alloy (AA 6061-T6 has been used for experimental and numerical analysis. Experimental analysis is based on temperature measurements by using infrared camera, whereas numerical analysis was based on empirical expressions and finite element method. Different types of defects have been observed in respect to different levels of heat input.

  16. Micro-scale abrasion behaviour of electroless Ni-P-SiC coating on aluminium alloy

    OpenAIRE

    2014-01-01

    Electroless nickel (EN) and electroless nickel composite (ENC) coatings were deposited on aluminium alloy substrate, LM24. The micro abrasion test was conducted to study the wear behaviour of the coatings with the effect of SiC concentration. Microhardness of the coatings was tested also. The wear scars were analysed using optical microscope and scanning electron microscope (SEM). The wear resistance was found to be improved in composite coating that has higher microhardness as compared to pa...

  17. High-temperature mechanical properties of aluminium alloys reinforced with boron carbide particles

    Energy Technology Data Exchange (ETDEWEB)

    Onoro, J. [Dept. Ingenieria y Ciencia de los Materiales, ETSI Industriales, Universidad Politecnica de Madrid, c/Jose Gutierrez Abascal 2, 28006 Madrid (Spain)], E-mail: javier.onoro@upm.es; Salvador, M.D. [Dept. Ingenieria Mecanica y de Materiales, ETSI Industriales, Universidad Politecnica de Valencia, Camino de Vera s/n, 46071 Valencia (Spain); Cambronero, L.E.G. [Dept. Ingenieria de Materiales, ETSI Minas, Universidad Politecnica de Madrid, c/Rios Rosas 21, 28003 Madrid (Spain)

    2009-01-15

    The mechanical properties of particulate-reinforced metal-matrix composites based on aluminium alloys (6061 and 7015) at high temperatures were studied. Boron carbide particles were used as reinforcement. All composites were produced by hot extrusion. The tensile properties and fracture analysis of these materials were investigated at room temperature and at high temperature to determine their ultimate strength and strain to failure. The fracture surface was analysed by scanning electron microscopy.

  18. Laser surface treatment of magnesium alloys with aluminium oxide powder

    Directory of Open Access Journals (Sweden)

    L.A. Dobrzański

    2009-11-01

    Full Text Available Purpose: The aim of this paper was to improve the magnesium cast alloys surface layer by laser surface treatment and to determine the laser treatment parameters.Design/methodology/approach: The laser treatment of magnesium alloys with alloying Al2O3 powder of the particle about 80μm was carried out using a high power diode laser (HPDL. The resulting microstructure in the modified surface layer was examined using scanning electron microscopy. Phase composition was determined by the X-ray diffraction method using the XPert device. The measurements of microhardness of the modified surface layer were also studied.Findings: The alloyed region has a fine microstructure with hard carbide particles. Microhardness of laser surface alloyed layer was significantly improved as compared to an alloy without laser treatment.Research limitations/implications: The investigations were conducted for cast magnesium alloys MCMgAl12Zn1, MCMgAl9Zn1, MCMgAl6Zn1, MCMgAl3Zn1 and Al2O3 powder of the particle size about 80 μm. One has used laser power in the range from 1.2to 2.0 kW.Practical implications: The results obtained in this investigation were promising comparing with the other conventional processes. High Power Diode Laser can be used as an economical substitute of Nd: YAG and CO2 to improve the surface magnesium alloy by feeding the carbide particles.Originality/value: The value of this paper is to define the influence of laser treatment parameters on quality, microstructure and microhardness of magnesium cast alloys surface layer.

  19. TEM and HRTEM studies of ball milled 6061 aluminium alloy powder with Zr addition.

    Science.gov (United States)

    Lityńska-Dobrzyńska, L; Dutkiewicz, J; Maziarz, W; Rogal, Ł

    2010-03-01

    The effect of mechanical alloying on the microstructure of atomized 6061 aluminium alloy powder and 6061 powder with a zirconium addition was studied in the work. The atomized 6061 aluminium alloy powder and 6061 powder with addition of 2 wt.% Zr were milled in a planetary ball mill and investigated using X-ray diffraction measurements, conventional and high-resolution electron microscopy (TEM/HRTEM) and high-angle annular dark field scanning transmission electron microscopy combined with energy dispersive X-ray microanalysis. An increase of stresses was observed in milled powders after the refinement of crystallites beyond 100 nm. In the powder with zirconium addition, some part of the Zr atoms diffused in aluminium forming a solid solution containing up to 0.5 wt.% Zr. The remaining was found to form Zr-rich particles containing up to 88 wt.% Zr and were identified as face centred cubic (fcc) phase with lattice constant a= 0.48 nm. That fcc phase partially transformed into the L1(2) ordered phase. Eighty-hour milling brought an increase of microhardness (measured with Vickers method) from about 50 HV (168 MPa) for the initial 6061 powder to about 170 HV (552 MPa). The addition of zirconium had no influence on the microhardness.

  20. 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....

  1. Experimental and simulation studies on laser conduction welding of AA5083 aluminium alloys

    Science.gov (United States)

    Tobar, M. J.; Lamas, M. I.; Yáñez, A.; Sánchez-Amaya, J. M.; Boukha, Z.; Botana, F. J.

    In this paper, a three-dimensional numerical model was developed to study laser welding in an aluminium alloy (AA5083). The CFD model was used to solve the governing equations of conservation of mass, momentum and energy, so as to obtain the morphology, velocity field and temperature field of the melted zone in steady state. The predicted dimensions of the weld pool agreed well with experimental results obtained on laser conduction welding with a (CW) high power diode laser. The study allowed to determine the effect of different surface treatment (sandblasting, black painting) on the laser absorptivity of the alloy and analyze the heat transfer mechanism within the weld pool.

  2. THE EFFECT OF THE ALUMINIUM ALLOY SURFACE ROUGHNESS ON THE RESTITUTION COEFFICIENT

    Directory of Open Access Journals (Sweden)

    Stanisław Bławucki

    2015-08-01

    Full Text Available The paper presents the results of research on the effect of the surface roughness of aluminum alloy on its coefficient of restitution. It describes the current method of finishing the workpiece surface layer after cutting and innovative measuring device which was used in the research. The material used in the research was aluminium alloy EN AW 7075. The paper also presents a relationship between the coefficient of restitution and surface roughness of the milled samples as well as impressions left by bead in function of velocity and a sample surface roughness.

  3. Protection of 2024-T3 aluminium alloy by corrosion resistant phytic acid conversion coating

    Science.gov (United States)

    Shi, Hongwei; Han, En-Hou; Liu, Fuchun; Kallip, Silvar

    2013-09-01

    The corrosion protection properties of environmentally friendly phytic acid conversion coatings were studied on 2024-T3 aluminium alloy. The films were prepared under acidic conditions with various pH values and characterised by SEM, EDS, ATR-FTIR and electrochemical techniques. The results indicate that the conversion coatings obtained by immersing the alloy in phytic acid solutions at pH from 3 to 5.5 provide excellent corrosion resistance. ATR-FTIR confirms that the film is formed by deposition of reaction products between Al3+ and phosphate groups in phytic acid molecules. The conformation models of the deposition film are proposed.

  4. 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 ma...

  5. 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...

  6. Fatigue behaviour of high strength AA 7012 aluminium alloy

    Energy Technology Data Exchange (ETDEWEB)

    Di Russo, E.; Ragazzini, R.; Buratti, M.; Ferrarin, C. (Aluminia-ISML, Novara (Italy) Caproni Vizzola costruzioni aeronautiche, Somma Lombarda (Italy))

    1990-02-01

    The alloy 7012 (Al, 6.2% Zn, 2% Mg, 1% Cn, 0.13% Mn, 0.14% Zn, 0.04% Ti) belongs to the 7XXX family of high mechanical resistance alloys containing Zr as the principal additive. Produced in the form of extrusions, sheets and forgings, the alloy finds application in the defense, transportation and power industry fields. This paper presents the results of experimental fatigue tests (10/sup 7/ cycles) on 7020 in the T6 and T73 temper conditions and draws comparisons with corresponding test results on 7075 and 2024 type alloys. A comparative analysis of S-N curves obtained from plane bending and axial fatigue tests on smooth and notched specimens evidences the superior performance of 7020 in terms of higher strength and corrosion cracking resistance.

  7. The Assessment of Modification of High-Zinc Aluminium Alloy

    Directory of Open Access Journals (Sweden)

    Zyska A.

    2014-06-01

    Full Text Available The results of examinations of the influence of titanium-boron inoculant on the solidification, the microstructure, and the mechanical properties of AlZn20 alloy are presented. The examinations were carried out for specimens cast both of the non-modified and the inoculated alloy. There were assessed changes in the alloy overcooling during the first stage of solidification due to the nuclei-forming influence of the inoculant. The results of quantitative metallographic measurements concerning the refinement of the grain structure of casting produced in sand moulds are presented. The cooling rate sensitivity of the alloy was proved by revealing changes in morphology of the α-phase primary crystals. Differences in mechanical properties resulting from the applied casting method and optional inoculation were evaluated.

  8. A predictive fatigue life model for anodized 7050 aluminium alloy

    OpenAIRE

    Chaussumier, Michel; Mabru, Catherine; Shahzad, Majid; Chieragatti, Rémy; Rezaï-Aria, Farhad

    2013-01-01

    International audience; The objective of this study is to predict fatigue life of anodized 7050 aluminum alloy specimens. In the case of anodized 7050-T7451 alloy, fractographic observations of fatigue tested specimens showed that pickling pits were the predominant sites for crack nucleation and subsequent failure. It has been shown that fatigue failure was favored by the presence of multiple cracks. From these experimental results, a fatigue life predictive model has been developed including...

  9. Effect of Laser Feeding on Heat Treated Aluminium Alloy Surface Properties

    Directory of Open Access Journals (Sweden)

    Labisz K.

    2016-06-01

    Full Text Available In this paper are presented the investigation results concerning microstructure as well as mechanical properties of the surface layer of cast aluminium-silicon-copper alloy after heat treatment alloyed and/ or remelted with SiC ceramic powder using High Power Diode Laser (HPDL. For investigation of the achieved structure following methods were used: light and scanning electron microscopy with EDS microanalysis as well as mechanical properties using Rockwell hardness tester were measured. By mind of scanning electron microscopy, using secondary electron detection was it possible to determine the distribution of ceramic SiC powder phase occurred in the alloy after laser treatment. After the laser surface treatment carried out on the previously heat treated aluminium alloys, in the structure are observed changes concerning the distribution and morphology of the alloy phases as well as the added ceramic powder, these features influence the hardness of the obtained layers. In the structure, there were discovered three zones: the remelting zone (RZ the heat influence zone (HAZ and transition zone, with different structure and properties. In this paper also the laser treatment conditions: the laser power and ceramic powder feed rate were investigated. The surface laser structure changes in a manner, that there zones are revealed in the form of. This carried out investigations make it possible to develop, interesting technology, which could be very attractive for different branches of industry.

  10. The Effect of Laser Surface Treatment on Structure and Mechanical Properties Aluminium Alloy ENAC-AlMg9

    Directory of Open Access Journals (Sweden)

    Pakieła W.

    2016-09-01

    Full Text Available In this work, the influence of a high power diode laser surface treatment on the structure and properties of aluminium alloy has been determined. The aim of this study was to improve the mechanical and tribological properties of the surface layer of the aluminium alloy by simultaneously melting and feeding tungsten carbide particles into the molten pool. During the process was used high-power diode laser HPDL. In order to remelt the aluminium alloy surface the HPDL laser of 1.8, 2.0 and 2.2 kW laser beam power has been used. The linear laser scan rate of the beam was set 0.5 cm/s. In order to protect the liquid metal during laser treatment was used argon. As a base material was used aluminium alloy ENAC-AlMg9. To improve the surface mechanical and wear properties of the applied aluminium alloy was used biphasic tungsten carbide WC/W2C. The size of alloying powder was in the range 110-210 µm. The ceramic powder was introduced in the remelting zone by a gravity feeder at a constant rate of 8 g/m.

  11. Modelling of non-metallic particles motion process in foundry alloys

    Directory of Open Access Journals (Sweden)

    P. L. Żak

    2015-04-01

    Full Text Available The behaviour of non-metallic particles in the selected composites was analysed, in the current study. The calculations of particles floating in liquids differing in viscosity were performed. Simulations based on the Stokes equation were made for spherical SiC particles and additionally the particle size influence on Reynolds number was analysed.The movement of the particles in the liquid metal matrix is strictly connected with the agglomerate formation problem.Some of collisions between non-metallic particles lead to a permanent connection between them. Creation of the two spherical particles and a metallic phase system generates the adhesion force. It was found that the adhesion force mainly depends on the surface tension of the liquid alloy and radius of non-metallic particles.

  12. Microstructure and Properties of Composite Coatings Obtained on Aluminium Alloys

    Directory of Open Access Journals (Sweden)

    Bara M.

    2016-09-01

    Full Text Available This paper presents methods of modifying the anode surface layers of Al2O3 by introducing carbon to their microstructure. Composite coatings were prepared using two different methods. In the first, coatings were formed by means of oxidation under constant current conditions. Anodic oxidation of aluminium was conducted in a multicomponent electrolyte with the addition of organic acids and graphite. The second method was based on the formation of oxide coatings in an electrolyte without the addition of graphite or heat treatment of the layers of succinic acid. The obtained coatings were tested using SEM, TEM, and GDOES (glow discharge optical emission spectrometry and their tribological and stereometric properties were measured. The study demonstrated the beneficial effects of the methods when used to improve the tribological properties of sliding couples.

  13. Corrosion behaviour of aluminium-magnesium alloys in molten sodium

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    The corrosion behaviour of the Al-1% Mg, A1-3% Mg, A1-5% Mg and A1-3% Mg-0.15%Zr alloys in moltensodium was investigated. The morphology of the corrosion products and the alloying element distribution of the specimenswere analyzed by using OM, SEM and EDS. The results showed that the effects of the magnesium content and the im-mersion temperature on the corrosion of the specimens are related to β phase (Mg5Al8).

  14. Experimental investigation of hardness of FSW and TIG joints of Aluminium alloys of AA7075 and AA6061

    Directory of Open Access Journals (Sweden)

    Chetan Patil

    2016-07-01

    Full Text Available This paper reports hardness testing conducted on welded butt joints by FSW and TIG welding process on similar and dissimilar aluminium alloys. FSW joints were produced for similar alloys of AA7075T651 and dissimilar alloys of AA7075T651- AA6061T6. The Friction stir welds of AA7075 & AA6061 aluminium alloy were produced at different tool rotational speeds of 650,700, 800, 900, 1000 and transverse speed of 30, 35, 40 mm/min. TIG welding was conducted along the rolling direction of similar and dissimilar aluminium plates. The Brinell hardness testing techniques were employed to conduct the tests; these tests were conducted on the welds to ascertain the joint integrity before characterization to have an idea of the quality of the welds

  15. Laser alloying of aluminium to improve surface properties - MSSA 2010

    CSIR Research Space (South Africa)

    Mabhali, Luyolo AB

    2010-07-01

    Full Text Available and microstructure of the surface without affecting the bulk properties of the material. The process involves melting the substrate surface and injecting the powder of the alloying material into the melt pool. Process parameters such as laser power, beam spot size...

  16. A hybrid aluminium alloy and its zoo of interacting nano-precipitates

    Energy Technology Data Exchange (ETDEWEB)

    Wenner, Sigurd, E-mail: sigurd.wenner@ntnu.no [Department of Physics, NTNU, Høgskoleringen 5, NO-7491 Trondheim (Norway); Marioara, Calin Daniel; Andersen, Sigmund Jarle [Materials and Chemistry, SINTEF, Høgskoleringen 5, NO-7491 Trondheim (Norway); Ervik, Martin; Holmestad, Randi [Department of Physics, NTNU, Høgskoleringen 5, NO-7491 Trondheim (Norway)

    2015-08-15

    An alloy with aluminium as its base element is heat treated to form a multitude of precipitate phases known from different classes of industrial alloys: Al–Cu(–Mg), Al–Mg–Si–Cu, and Al–Zn–Mg. Nanometer-sized needle-shaped particles define the starting point of the phase nucleation, after which there is a split in the precipitation sequence into six phases of highly diverse compositions and morphologies. There are several unique effects of phases from different alloy systems being present in the same host lattice, of which we concentrate on two: the replacement of Ag by Zn on the Ω interface and the formation of combined plates of the θ′ and C phases. Using atomically resolved scanning transmission electron microscopy and energy-dispersive X-ray spectroscopy, we investigate the formation mechanisms, crystal structures and compositions of the precipitates. - Graphical abstract: Display Omitted - Highlights: • An aluminium alloy composition in-between the 2/6/7xxx systems was investigated. • Six different phases from the three systems coexist in an over-aged state. • All phases with 〈001〉{sub Al} coherencies can nucleate on 6xxx needle precipitates. • Modified theta′ and omega interfaces are observed.

  17. Study of surface interactions of ionic liquids with aluminium alloys in corrosion and erosion corrosion processes

    Science.gov (United States)

    Bermúdez, María-Dolores; Jiménez, Ana-Eva; Martínez-Nicolás, Ginés

    2007-06-01

    Surface interactions of alkylimidazolium ionic liquids (ILs) with aluminium alloy Al 2011 have been studied by immersion tests in seven neat ILs [1- n-alkyl-3-methylimidazolium X - (X = BF 4; n = 2 (IL1), 6 (IL2), 8 (IL3). X = CF 3SO 3; n = 2 (IL4). X = (4-CH 3C 6H 4SO 3); n = 2 (IL5). X = PF 6; n = 6 (IL6)] and 1-butyl-3-methylpyridinium bis(trifluoromethylsulfonyl)imide (IL7)]. Immersion tests for Al 2011 have also been carried out in 1 wt.% and 5 wt.% solutions of 1-ethyl,3-methylimidazolium tetrafluoroborate (IL1) in water. No corrosion of Al 2011 by neat ILs is observed. The highest corrosion rate for Al 2011 in water is observed in the presence of a 5 wt.% IL1 due to hydrolysis of the anion with hydrogen evolution and formation of aluminium fluoride. Erosion-corrosion processes have been studied for three aluminium alloys (Al 2011, Al 6061 and Al 7075) in a 90 wt.% IL1 solution in water in the presence of α-alumina particles. The erosion-corrosion rates are around 0.2 mm/year or lower, and increase with increasing copper content to give a corrosion resistance order of Al 6061 > Al 7075 > Al 2011. Results are discussed on the basis of scanning electron microscopy (SEM) observations, energy dispersive spectroscopy (EDS) analysis, X-ray diffraction (XRD) patterns and X-ray photoelectron spectroscopy (XPS) determinations.

  18. Analysis of wear properties of aluminium based journal bearing alloys with and without lubrication.

    Science.gov (United States)

    Mathavan, J. Joy; Patnaik, Amar

    2016-09-01

    Apart from classical bearing materials, Aluminium alloys are used as bearing materials these days because of their superior quality. In this analysis, new Aluminium based bearing materials, with filler metals Si, Ni, and Cr are prepared by metal mould casting in burnout furnace machine, and tribological properties of these alloys with and without lubrication were tested. The experiments for wear with lubrication are conducted on multiple specimen tester and experiments without lubrication is conducted on Pin on disk tribometer. The disc material used was SAE 1050 steel. Wear tests were conducted at a sliding speed of 0.785 m/s and at a normal load of 20 N. Coefficient of friction values, temperature changes and wear of the specimens were plotted on graph according to the above mentioned working conditions. Hardness and weight losses of the specimens were calculated. The obtained results demonstrate how the friction and wear properties of these samples have changed with the % addition of Silicon, Chromium and Nickel to the base metal aluminium.

  19. Gating System Design for Casting thin Aluminium Alloy (Al-Si Plates

    Directory of Open Access Journals (Sweden)

    Victor ANJO

    2013-11-01

    Full Text Available The main problems caused by improper gating are entrained aluminium oxide films, cuts and washes, low casting yield and entrapped gas. This study describes the design of a gating system to produce thin Aluminium cast alloy plates of different sizes and thicknesses of 4mm, 6mm, 8mm, and 10mm using the non-pressurized gating with ratio of 1:4:4 and green sand moulding technique. The gating design was based on the laws of fluid mechanics and empirical rules of gating for non ferrous metals. The equipments used for this experiment includes; a coal fired crucible furnace and an X-Ray machine. Materials used include; silica sand, clay, wood, glue and Aluminium alloy scraps. The experimental procedure involved: the gating design calculations, construction of wooden pattern and gating; using the wooden pattern and gating to produce the mould cavities and gating; melting, melt treatment and pouring of melt in the sand mould to produce the casting. The plate castings after removal from mould were visually examined for surface defects and after fettling and cleaning X-Ray radiography was used to find the internal soundness of the castings. From the results obtained in the experiment, it was found that there were no internal defects and quality castings were produced.

  20. Structural stability of the high-aluminium zinc alloys modified with Ti addition

    Directory of Open Access Journals (Sweden)

    W.K. Krajewski

    2012-01-01

    Full Text Available The subject of the paper is structural stability of the Zn-26 wt.% Al binary alloys doped with 2.2 wt.% Cu or 1.6 wt.% Ti addition. The structural stability of Zn-Al alloys with increased Al content is connected with stability of solid solution of zinc in aluminium α', which is the main component of these alloys microstructure. Such a solution undergoes phase transformations which are accompanied, among others, by changes in dimensions and strength properties.The structural stability of the ZnAL26Cu2.2 and ZnAl26Ti1.6 alloys was investigated using XRD examinations during long term natural ageing after casting, as well as during long term natural ageing after super-saturation and quenching. On the basis of the performed examinations it was stated that small Ti addition to the binary ZnAl25 alloy, apart from structure refinement, accelerates decomposition of the primary α' phase giving stable structure in a shorter period of time in comparison with the alloy without Ti addition. Addition of Ti in amount of 1.6 wt.%, totally replacing Cu, allows obtaining stable structure and dimensions and allows avoiding structural instability caused by the metastable ε−CuZn4phase present in the ZnAl26Cu2.2 alloy.

  1. Effect of pulsed current welding on fatigue behaviour of high strength aluminium alloy joints

    Energy Technology Data Exchange (ETDEWEB)

    Balasubramanian, V. [Department of Manufacturing Engineering, Annamalai University, Annamalai Nagar 608 002, Tamil Nadu (India)], E-mail: visvabalu@yahoo.com; Ravisankar, V. [Department of Manufacturing Engineering, Annamalai University, Annamalai Nagar 608 002, Tamil Nadu (India); Madhusudhan Reddy, G. [Metal Joining Section, Defence Metallurgical Research Laboratory (DMRL), Kanchanbag (P.O), Hyderabad 560 058 (India)

    2008-07-01

    High strength aluminium alloys (Al-Zn-Mg-Cu alloys) have gathered wide acceptance in the fabrication of light weight structures requiring high strength-to weight ratio, such as transportable bridge girders, military vehicles, road tankers and railway transport systems. The preferred welding processes of high strength aluminium alloy are frequently gas tungsten arc welding (GTAW) process and gas metal arc welding (GMAW) process due to their comparatively easier applicability and better economy. Weld fusion zones typically exhibit coarse columnar grains because of the prevailing thermal conditions during weld metal solidification. This often results inferior weld mechanical properties and poor resistance to hot cracking. In this investigation, an attempt has been made to refine the fusion zone grains by applying pulsed current welding technique. Rolled plates of 6 mm thickness have been used as the base material for preparing single pass welded joints. Single V butt joint configuration has been prepared for joining the plates. The filler metal used for joining the plates is AA 5356 (Al-5Mg (wt%)) grade aluminium alloy. Four different welding techniques have been used to fabricate the joints and they are: (i) continuous current GTAW (CCGTAW), (ii) pulsed current GTAW (PCGTAW), (iii) continuous current GMAW (CCGMAW) and (iv) pulsed current GMAW (PCGMAW) processes. Argon (99.99% pure) has been used as the shielding gas. Fatigue properties of the welded joints have been evaluated by conducting fatigue test using rotary bending fatigue testing machine. Current pulsing leads to relatively finer and more equi-axed grain structure in gas tungsten arc (GTA) and gas metal arc (GMA) welds. In contrast, conventional continuous current welding resulted in predominantly columnar grain structures. Grain refinement is accompanied by an increase in fatigue life and endurance limit.

  2. The fatigue response of the aluminium-lithium alloy, 8090

    Science.gov (United States)

    Birt, M. J.; Beevers, C. J.

    1989-01-01

    The fatigue response of an Al-Li-Cu-Mg-Zr (8090) alloy has been studied at room temperature. The initiation and growth of small and long cracks has been examined at R = 0.1 and at a frequency of 100 Hz. Initiation was observed to occur dominantly at sub-grain boundaries. The growth of the small cracks was crystallographic in character and exhibited little evidence of retardation or arrest at the grain boundaries. The long crack data showed the alloy to have a high resistance to fatigue crack growth with underaging providing the optimum heat treatment for fatigue crack growth resistance. In general, this can be attributed to high levels of crack closure which resulted from the presence of extensive microstructurally related asperities.

  3. The fatigue response of the aluminium-lithium alloy, 8090

    Science.gov (United States)

    Birt, M. J.; Beevers, C. J.

    1989-01-01

    The fatigue response of an Al-Li-Cu-Mg-Zr (8090) alloy has been studied at room temperature. The initiation and growth of small and long cracks has been examined at R = 0.1 and at a frequency of 100 Hz. Initiation was observed to occur dominantly at sub-grain boundaries. The growth of the small cracks was crystallographic in character and exhibited little evidence of retardation or arrest at the grain boundaries. The long crack data showed the alloy to have a high resistance to fatigue crack growth with underaging providing the optimum heat treatment for fatigue crack growth resistance. In general, this can be attributed to high levels of crack closure which resulted from the presence of extensive microstructurally related asperities.

  4. 3D study of intermetallics and their effect on the corrosion morphology of rheocast aluminium alloy

    Energy Technology Data Exchange (ETDEWEB)

    Mingo, B. [Departamento de Ciencia de Materiales, Facultad de Ciencias Químicas, Universidad Complutense, 28040, Madrid (Spain); Arrabal, R., E-mail: rarrabal@ucm.es [Departamento de Ciencia de Materiales, Facultad de Ciencias Químicas, Universidad Complutense, 28040, Madrid (Spain); Pardo, A.; Matykina, E. [Departamento de Ciencia de Materiales, Facultad de Ciencias Químicas, Universidad Complutense, 28040, Madrid (Spain); Skeldon, P. [Corrosion and Protection Group, School of Materials, The University of Manchester, Manchester M13 9PL (United Kingdom)

    2016-02-15

    In the present study, the effect of heat treatment T6.1 on the microstructure and corrosion behaviour of rheocast aluminium alloy A356 is investigated on the basis of 2D/3D characterization techniques and electrochemical and SKPFM measurements. Heat treatment strengthens the α-Al matrix, modifies the intermetallic particles and spheroidizes eutectic Si. These changes do not modify significantly the corrosion behaviour of the alloy. 3D SEM-Tomography clearly shows that the corrosion advances in the shape of narrow paths between closely spaced intermetallics without a major influence of eutectic Si. - Highlights: • T6.1 spheroidizes Si, strengthens the matrix and modifies the intermetallics. • Electrochemical behaviour of untreated and heat-treated alloys is similar. • 3D SEM-Tomography provides additional information on the corrosion morphology. • Corrosion advances as paths between intermetallics with little influence of Si.

  5. Fabrication of self-healing super-hydrophobic surfaces on aluminium alloy substrates

    Directory of Open Access Journals (Sweden)

    Yang Wang

    2015-04-01

    Full Text Available We present a method to fabricate a super-hydrophobic surface with a self-healing ability on an aluminium alloy substrate. The coatings are obtained by combining a two-step process (first, the substrate is immersed in a solution of HCl, HF and H2O, and then in boiling water and succeeding surface fluorination with a solution of poly(vinylidene-fluoride-co-hexafluoropropylene and a fluoroalkyl silane. The morphological features and chemical composition were studied by scanning electron micrometry and energy-dispersive X-ray spectroscopy. The prepared super-hydrophobic aluminium surfaces showed hierarchical structures forming pores, petals and particles with a contact angle of 161° and a sliding angle of 3°.

  6. Surface morphology, composition and thermal behavior of tungsten-containing anodic spark coatings on aluminium alloy

    Energy Technology Data Exchange (ETDEWEB)

    Lukiyanchuk, I.V.; Rudnev, V.S.; Kuryavyi, V.G.; Boguta, D.L.; Bulanova, S.B.; Gordienko, P.S

    2004-01-01

    Anodic spark coatings on aluminium alloy were prepared in aqueous electrolytes with sodium tungstate. The influence of boric acid addition in the electrolyte on the surface morphology, elemental and phase composition of the coatings was investigated. In both cases the coatings contained O, Al and W. The coatings obtained in electrolyte with boric acid and sodium tungstate contain also B at approximately 1 at.%. Scanning electron microscopy indicated that the coatings had three layers: the grey underlayer of anodic alumina, the second black layer of crystalline or amorphous aluminium tungstate agglomerated into fibers and the outer green layer of WO{sub 3}. It was proposed that isopoly- and heteropolyanions in the electrolyte used take part in the coating growth.

  7. Determination of lattice orientation in aluminium alloy grains by low energy gallium ion-channelling

    Science.gov (United States)

    Silk, Jonathan R.; Dashwood, Richard J.; Chater, Richard J.

    2010-06-01

    Polished sections of a fine-grained aluminium, silicon carbide metal matrix composite (MMC) alloy were prepared by sputtering using a low energy gallium ion source and column (FIB). The MMC had been processed by high temperature extrusion. Images of the polished surface were recorded using the ion-induced secondary electron emission. The metal matrix grains were distinguished by gallium ion-channelling contrast from the silicon carbide component. The variation of the contrast from the aluminium grains with tilt angle can be recorded and used to determine lattice orientation with the contrast from the silicon carbide (SiC) component as a reference. This method is rapid and suits site-specific investigations where classical methods of sample preparation fail.

  8. 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.

  9. 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.

  10. Electron irradiation of aluminium-zinc alloys. 3. Radiation-enhanced precipitation in an aluminium-4.5 at% zinc alloy

    Science.gov (United States)

    Zhang, Y. G.

    1989-06-01

    An aluminium-4.5 at% zinc alloy was irradiated at temperatures between 25 and 170°C to doses of 7 dpa to 14 dpa at a dose rate of ~3.88 × 10 -3dpa/s. Irradiation produced a very high density of coherent G.P. zones in the temperature range ~80-~130°C, coherent plate shaped precipitates in the temperature range ~130-~160°C and, under some irradiation conditions, large Zn precipitates on the foil surfaces. No precipitates occurred along the grain boundaries in the irradiated area. The matrix precipitation was interpreted in terms of the theory of Cauvin and Martin. The surface precipitation is ascribed to surface segregation of Zn and the non-appearance of precipitates along the grain boundaries in the irradiated area is thought to be due to the high metastability of the precipitates on the boundaries under irradiation.

  11. Experimental and theoretical investigation on corrosion inhibition of AA5052 aluminium alloy by L-cysteine in alkaline solution

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Dapeng; Gao, Lixin [School of Environmental and Chemical Engineering, Shanghai University of Electric Power, Shanghai 200090 (China); Zhang, Daquan, E-mail: zhangdaquan@shiep.edu.cn [School of Environmental and Chemical Engineering, Shanghai University of Electric Power, Shanghai 200090 (China); Yang, Dong [School of Environmental and Chemical Engineering, Shanghai University of Electric Power, Shanghai 200090 (China); Wang, Hongxia; Lin, Tong [Institute for Frontier Materials, Deakin University, Geelong, VIC 3216 (Australia)

    2016-02-01

    The corrosion inhibition of L-cysteine on AA5052 aluminium alloy in 4 mol/L NaOH solution was investigated by hydrogen gas evolution experiment, polarisation curve, galvanostatic discharge, electrochemical impedance spectroscopy measurements and quantum chemical calculations. The adsorption of L-cysteine on aluminium alloy surface obeyed the amended Langmuir's adsorption isotherm. The polarisation curves indicated that L-cysteine acted as a cathodic inhibitor to inhibit cathodic reaction. The inhibition mechanism was dominated by the geometric covering effect. The galvanostatic discharge shows that the additives restrain the hydrogen evolution and increase the anodic utilization rate. Quantum chemical calculations indicated that L-cysteine molecules mainly interacted with on the carboxyl groups on the aluminium alloy surface. A strong hybridization occurred between the s-orbital and p-orbital of reactive sites in the L-cysteine molecule and the sp-orbital of Aluminium. - Highlights: • L-cysteine was used as corrosion inhibitor for Al alloy in alkaline solution. • Adsorption of L-cysteine on Al alloy surface obeyed the amended Langmuir's isotherm. • L-cysteine molecules interacted with the carboxyl groups on the Al alloy surface. • A strong orbital hybridization occurred between the reactive sites in L-cysteine and Al.

  12. Further studies of the anodic dissolution in sodium chloride electrolyte of aluminium alloys containing tin and gallium

    Science.gov (United States)

    Nestoridi, Maria; Pletcher, Derek; Wharton, Julian A.; Wood, Robert J. K.

    As part of a programme to develop a high power density, Al/air battery with a NaCl brine electrolyte, the high rate dissolution of an aluminium alloy containing tin and gallium was investigated in a small volume cell. The objective was to define the factors that limit aluminium dissolution in condition that mimic a high power density battery. In a cell with a large ratio of aluminium alloy to electrolyte, over a range of current densities the extent of dissolution was limited to ∼1000 C cm -2 of anode surface by a thick layer of loosely bound, crystalline deposit on the Al alloy anode formed by precipitation from solution. This leads to a large increase in impedance and acts as a barrier to transport of ions.

  13. Further studies of the anodic dissolution in sodium chloride electrolyte of aluminium alloys containing tin and gallium

    Energy Technology Data Exchange (ETDEWEB)

    Nestoridi, Maria; Pletcher, Derek [The School of Chemistry, University of Southampton, Highfield, Southampton SO17 1BJ (United Kingdom); Wharton, Julian A.; Wood, Robert J.K. [School of Engineering Sciences, The University, Southampton SO17 1BJ (United Kingdom)

    2009-09-05

    As part of a programme to develop a high power density, Al/air battery with a NaCl brine electrolyte, the high rate dissolution of an aluminium alloy containing tin and gallium was investigated in a small volume cell. The objective was to define the factors that limit aluminium dissolution in condition that mimic a high power density battery. In a cell with a large ratio of aluminium alloy to electrolyte, over a range of current densities the extent of dissolution was limited to {proportional_to}1000 C cm{sup -2} of anode surface by a thick layer of loosely bound, crystalline deposit on the Al alloy anode formed by precipitation from solution. This leads to a large increase in impedance and acts as a barrier to transport of ions. (author)

  14. Modelling the processing of aluminium alloys in the semi-solid state

    Energy Technology Data Exchange (ETDEWEB)

    Wahlen, A. [ARC Leichtmetallkompetenzzentrum Ranshofen GmbH, Ranshofen (Austria)

    2002-07-01

    Thixoforming, an innovative technique in which metals are formed in their semi-solid state, permits the cost-efficient production of components with improved properties and performance compared to conventional pressure die casting. Since this process is still relatively new, great technical advances can be expected in the near future. These advances should allow production of near-net-shape components with good mechanical properties, combined with low manufacturing cost. Due to the distinct thixotropic flow pattern of the semi-solid slurry, high production speeds similar to those of conventional pressure die casting can be achieved, yet the disadvantages of the latter are eliminated: thixoformed components possess a good combination of strength and ductility, and they are heat-treatable and weldable. The requirement for thixotropic flow behaviour is a particular microstructure in the semi-solid state. At the onset of forming, the solid phase of the material must exhibit a globular morphology, a feature that can be produced with a novel casting technique called new rheocasting (NRC). Cast billets of several aluminium alloys and resulting microstructures show the feasibility of the chosen process variant. Constitutive models for the distinct flow behaviour of thixotropic aluminium alloys in the semi-solid state are derived with respect to temperature, strain rate and microstructure. Experimental techniques such as deformation tests, backward extrusion experiments, differential thermal analysis and quantitative metallurgy provide the necessary data to calibrate the materials models. For the implementation in a special-purpose FE software package, constitutive models for the thixotropic flow stress, the specific thixotropic flow stress, the specific heat capacity and the thermal conductivity of cast and wrought aluminium alloys in the semi-solid state are provided. For the optimization of the thixoforming manufacturing process these models were implemented in the FE

  15. Prediction of flow stress of 7017 aluminium alloy under high strain rate compression at elevated temperatures

    Institute of Scientific and Technical Information of China (English)

    Ravindranadh BOBBILI; B. RAMAKRISHNA; V. MADHU; A.K. GOGIA

    2015-01-01

    An artificial neural network (ANN) constitutive model and JohnsoneCook (JeC) model were developed for 7017 aluminium alloy based on high strain rate data generated from split Hopkinson pressure bar (SHPB) experiments at various temperatures. A neural network configuration consists of both training and validation, which is effectively employed to predict flow stress. Temperature, strain rate and strain are considered as inputs, whereas flow stress is taken as output of the neural network. A comparative study on JohnsoneCook (JeC) model and neural network model was performed. It was observed that the developed neural network model could predict flow stress under various strain rates and tem-peratures. The experimental stressestrain data obtained from high strain rate compression tests using SHPB over a range of temperatures (25?e300 ?C), strains (0.05e0.3) and strain rates (1500e4500 s?1) were employed to formulate JeC model to predict the flow stress behaviour of 7017 aluminium alloy under high strain rate loading. The JeC model and the back-propagation ANN model were developed to predict the flow stress of 7017 aluminium alloy under high strain rates, and their predictability was evaluated in terms of correlation coefficient (R) and average absolute relative error (AARE). R and AARE for the J-C model are found to be 0.8461 and 10.624%, respectively, while R and AARE for the ANN model are 0.9995 and 2.58%, respectively. The predictions of ANN model are observed to be in consistent with the experimental data for all strain rates and temperatures.

  16. Accelerated growth of oxide film on aluminium alloys under steam: Part II: Effects of alloy chemistry and steam vapour pressure on corrosion and adhesion performance

    DEFF Research Database (Denmark)

    Din, Rameez Ud; Bordo, Kirill; Jellesen, Morten Stendahl

    2015-01-01

    The steam treatment of aluminium alloys with varying vapour pressure of steamresulted in the growth of aluminium oxyhydroxide films of thickness range between 450 - 825nm. The surface composition, corrosion resistance, and adhesion of the produced films was characterised by XPS, potentiodynamic...... of the vapour pressure of the steam. The accelerated corrosion and adhesion tests on steam generated oxide films with commercial powder coating verified that the performance of the oxide coating is highly dependent on the vapour pressure of the steam....

  17. Accelerated growth of oxide film on aluminium alloys under steam: Part II: Effects of alloy chemistry and steam vapour pressure on corrosion and adhesion performance

    DEFF Research Database (Denmark)

    Din, Rameez Ud; Bordo, Kirill; Jellesen, Morten Stendahl;

    2015-01-01

    The steam treatment of aluminium alloys with varying vapour pressure of steamresulted in the growth of aluminium oxyhydroxide films of thickness range between 450 - 825nm. The surface composition, corrosion resistance, and adhesion of the produced films was characterised by XPS, potentiodynamic...... of the vapour pressure of the steam. The accelerated corrosion and adhesion tests on steam generated oxide films with commercial powder coating verified that the performance of the oxide coating is highly dependent on the vapour pressure of the steam....

  18. Investigation of photocatalytic activity of titanium dioxide coating deposited on aluminium alloy substrate by plasma technique

    DEFF Research Database (Denmark)

    Daviðsdóttir, Svava; Soyama, Juliano; Dirscherl, Kai

    2011-01-01

    . Literature consists of large number of publications on titanium dioxide coating for self-cleaning applications, with glass as the main substrate. Only little work is available on TiO2 coating of metallic alloys used for engineering applications. Engineering materials, such as light-weight aluminium and steel...... of the coating strongly influences the photocatalytic properties. In general, the photocatalytic activity increased with thickness. Quantification of images scanned with Atomic Force Microscope (AFM) revealed that there is a linear relationship between the thickness of the coating and the average cell size...

  19. Research of aluminium alloy aerospace structure aperture measurement based on 3D digital speckle correlation method

    Science.gov (United States)

    Bai, Lu; Wang, Hongbo; Zhou, Jiangfan; Yang, Rong; Zhang, Hui

    2014-11-01

    In this paper, the aperture change of the aluminium alloy aerospace structure under real load is researched. Static experiments are carried on which is simulated the load environment of flight course. Compared with the traditional methods, through experiments results, it's proved that 3D digital speckle correlation method has good adaptability and precision on testing aperture change, and it can satisfy measurement on non-contact,real-time 3D deformation or stress concentration. The test results of new method is compared with the traditional method.

  20. A vertical type twin roll caster for an aluminium alloy clad strip

    OpenAIRE

    T. Haga; Nakamura, R; Kuma, S; H. Watari

    2013-01-01

    Purpose: of this paper: Twin roll casters that can cast two layers and three layers clad strip of aluminium alloys were invented. One of the purposes of this paper is to report that the two layers and three layers clad strip could be cast by the twin roll caster of this study. The investigation of the characters of these casters and the clad strips was purpose of this paper, too. The connecting at the interface between the strips was most important in the casting of the clad strip. Therefore,...

  1. Grain refining of aluminium alloys and silicon by means of boron-nitride particles

    Energy Technology Data Exchange (ETDEWEB)

    Wulf, Eric; Seitz, Jan-Marten; Schaper, Mirko; Bach, Friedrich-Wilhelm [Leibniz Univ. of Hannover, Garbsen (Germany). Inst. of Materials Science; Alphei, Lukas David; Westphal, David; Becker, Joerg August; Feldhoff, Armin [Leibniz Univ. of Hannover, Garbsen (Germany). Inst. of Physical Chemistry and Electrochemistry

    2013-03-15

    Investigations were carried out to grain refine the aluminium alloys Al-6Si (all compositions given in wt.%) and Al-12Si as well as pure silicon by means of inoculation using boron nitride nano-particles. Comparative tests were performed using both conventional grain refiners based on titanium as well as without inoculants. Analyses were performed using scanning electron microscopy, tensile testing, thermographic and metallographic techniques. In doing this, a significant effect on grain refining is verified by inoculating using boron nitride which exceeds the effect of conventional grain refiners. (orig.)

  2. ANN & ANFIS Models for Prediction of Abrasive Wear of 3105 Aluminium Alloy with Polyurethane Coating

    Directory of Open Access Journals (Sweden)

    H. Alimam

    2016-06-01

    Full Text Available The quest for safety and reliability has increased significantly after Industrial revolution, so is the case for coating industries. In this paper 3105 Aluminium alloy sheet is coated with organic polyurethane coating. After the implementation of coating, various processes are undergone to check its reliability under elevated conditions. ANN & ANFIS model were developed and trained with an objective to find abrasive wear during the process. ANN & ANFIS model were compared with the experimental results. It is observed that the abrasive wear of a coated specimen can be predicted accurately and precisely using ANN and ANFIS models.

  3. SOLIDIFICATION CHARACTERISTIC OF TITANIUM CARBIDE PARTICULATE REINFORCED ALUMINIUM ALLOY MATRIX COMPOSITES

    Directory of Open Access Journals (Sweden)

    N. FATCHURROHMAN

    2012-04-01

    Full Text Available In this research solidification characteristic of metal matrix composites consisted of titanium carbide particulate reinforced aluminium-11.8% silicon alloy matrix is performed. Vortex mixing and permanent casting method are used as the manufacturing method to produce the specimens. Temperature measurements during the casting process are captured and solidification graphs are plotted to represent the solidification characteristic. The results show, as volume fraction of particulate reinforcement is increased, solidification time is faster. Particulate reinforcement promotes rapid solidification which will support finer grain size of the casting specimen. Hardness test is performed and confirmed that hardness number increased as more particulate are added to the system.

  4. Parametric study of friction stir spot welding of aluminium alloy 5754

    Directory of Open Access Journals (Sweden)

    D. Klobčar

    2014-01-01

    Full Text Available The paper presents a parametric analysis of friction stir spot welding (FSSW of aluminium alloy 5754 in a lap joint. Experimental plan was done according to the response surface methodology (RSM, where tool rotation speed varied between 988 and 3511 rpm, plunge rate between 24,4 and 150 mm/min and dwell time between 1 and 3,5s. The plunge depth was held constant at 0,4 mm. The welds were tensile-shear tested and the microstructure was analysed. Mathematical models describing the relationship between welding parameters and spot strength, axial force and rotational moment were developed and the optimal FSSW parameters were found.

  5. Rapid and selective chelatometric titration of aluminium in non-ferrous alloys.

    Science.gov (United States)

    Nan, Z; Yuan-Xiang, G; Zhi-Ren, L; Eei-Yong, C

    1985-12-01

    A rapid chelatometric method for the determination of Al (4-20%) in magnesium, copper and chromium-aluminium-iron alloys is proposed. HEDTA is used as titrant and Zn solution as back-titrant, with hydrazidazol as indicator. Mn(II), Cu(II), Cd, Zn, Pb, Co(II), Ni, Hg(II), Fe(III), Bi, Cr(III), Sb(III), Ce(III), La, Sn(IV), Ti(IV), Zr and Mo(VI) do not interfere. High selectivity is achieved by a combination of group separation, masking and interference correction. The coefficient of variation varies from 0.2 to 1%.

  6. Tribological Potential of Hybrid Composites Based on Zinc and Aluminium Alloys Reinforced with SiC and Graphite Particles

    Directory of Open Access Journals (Sweden)

    D. Džunić

    2012-12-01

    Full Text Available The paper reviews contemporary research in the area of hybrid composites based on zinc and aluminium alloys reinforced with SiC and graphite particles. Metal matrix composites (MMCs based on ZA matrix are being increasingly applied as light-weight and wear resistant materials. Aluminium matrix composites with multiple reinforcements (hybrid AMCsare finding increased applications because of improved mechanical and tribological properties and hence are better substitutes for single reinforced composites. The results of research show that the hybrid composites possess higher hardness, higher tensile strength, better wear resistance and lower coefficient of friction when compared to pure alloys.

  7. Effect of Lubrication on Sliding Wear of Red Mud Particulate Reinforced Aluminium Alloy 6061

    Directory of Open Access Journals (Sweden)

    N. Panwar

    2017-09-01

    Full Text Available In present study, Red mud, an industrial waste, has been utilized as a reinforcement material to fabricate Aluminium 6061 matrix based metal matrix composite. Taguchi L18 orthogonal array has been employed for fabrication of composite castings and for conducting the tribological experimentation. ANOVA analysis has been applied to examine the effect of individual parameters such as sliding condition: dry and wet, reinforcement weight fraction, load, speed, and sliding distance on specific wear rate obtained experimentally. It has been found that tensile strength and impact energy increases while elongation decreases, with increasing weight fraction and decrease in particle size of red mud. The percentage contribution of the effect of factors on SWR is Sliding condition (73.17, speed (7.84, percentage reinforcement (7.35, load (5.75, sliding distance (2.24, and particle size (1.25. It has also been observed that specific wear rate is very low in wet condition. However, it decreases with increase in weight fraction of reinforcement, decrease in load and sliding speed. Al6061/red mud metal matrix composites have shown reasonable strength and wear resistance. The use of red mud in Aluminium composite provides the solution for disposal of red mud and can possibly become an economic replacement of Aluminium and its alloys.

  8. Influence of Process Parameters on the Quality of Aluminium Alloy EN AW 7075 Using Selective Laser Melting (SLM)

    Science.gov (United States)

    Kaufmann, N.; Imran, M.; Wischeropp, T. M.; Emmelmann, C.; Siddique, S.; Walther, F.

    Selective laser melting (SLM) is an additive manufacturing process, forming the desired geometry by selective layer fusion of powder material. Unlike conventional manufacturing processes, highly complex parts can be manufactured with high accuracy and little post processing. Currently, different steel, aluminium, titanium and nickel-based alloys have been successfully processed; however, high strength aluminium alloy EN AW 7075 has not been processed with satisfying quality. The main focus of the investigation is to develop the SLM process for the wide used aluminium alloy EN AW 7075. Before process development, the gas-atomized powder material was characterized in terms of statistical distribution: size and shape. A wide range of process parameters were selected to optimize the process in terms of optimum volume density. The investigations resulted in a relative density of over 99%. However, all laser-melted parts exhibit hot cracks which typically appear in aluminium alloy EN AW 7075 during the welding process. Furthermore the influence of processing parameters on the chemical composition of the selected alloy was determined.

  9. Property Evaluation of Friction Stir Welded Dissimilar Metals : AA6101-T6 and AA1350 Aluminium Alloys

    Directory of Open Access Journals (Sweden)

    Rajendran ASHOK KUMAR

    2017-02-01

    Full Text Available Next to copper, aluminium alloys are widely used in electrical industries, because of their high electrical conductivity. AA6101-T6 and AA1350 aluminium alloys are widely used in electrical bus bars. As these alloys are joined by mechanical fasteners in electrical bus bars, the conductive area has been reduced. To avoid this problem, they should be joined without removal of metal as well as their properties. Friction stir welding technique is mainly invented for joining similar and dissimilar aluminium alloys. In this investigation, friction stir welding of AA6101-T6 and AA1350 aluminium alloys was done by varying tool traversing speed, rotational speed and tilt angle with hexagonal pin profiled tool. The analysis of variance was employed to study the effect of above parameters on mechanical properties of welded joints. From the experimental results, it is observed that welded joint with the combination of 1070 rpm rotating speed, 78 mm/min traversing speed and 2° tilt angle provides better mechanical properties. Analysis of variance shows that most significant impact on tensile strength is made by variation in tool rotating speed while tool tilt angle makes the most significant impact on elongation and bending strength.DOI: http://dx.doi.org/10.5755/j01.ms.23.1.14132

  10. Corrosion protection of Mg/Al alloys by thermal sprayed aluminium coatings

    Energy Technology Data Exchange (ETDEWEB)

    Pardo, A., E-mail: anpardo@quim.ucm.es [Departamento de Ciencia de Materiales, Facultad de Quimicas, Universidad Complutense, 28040 Madrid (Spain); Casajus, P.; Mohedano, M.; Coy, A.E.; Viejo, F. [Departamento de Ciencia de Materiales, Facultad de Quimicas, Universidad Complutense, 28040 Madrid (Spain); Torres, B. [Departamento de Ciencia e Ingenieria de Materiales, ESCET, Universidad Rey Juan Carlos, 28933 Mostoles, Madrid (Spain); Matykina, E. [Corrosion and Protection Centre, School of Materials, The University of Manchester, P.O. Box 88, Sackville Street, Manchester M60 1QD (United Kingdom)

    2009-05-15

    The protective features of thermal sprayed Al-coatings applied on AZ31, AZ80 and AZ91D magnesium/aluminium alloys were evaluated in 3.5 wt.% NaCl solution by electrochemical and gravimetric measurements. The changes in the morphology and corrosion behaviour of the Al-coatings induced by a cold-pressing post-treatment were also examined. The specimens were characterized by scanning electron microscopy, energy dispersive X-ray analysis and low-angle X-ray diffraction. The as-sprayed Al-coatings revealed a high degree of porosity and poor corrosion protection, which resulted in galvanic acceleration of the corrosion of the magnesium substrates. The application of a cold-pressing post-treatment produced more compact Al-coatings with better bonding at the substrate/coating interface and higher corrosion resistance regardless of the nature of the magnesium alloy.

  11. Modeling of microstructural evolution and flow stress of aluminium alloy during thermomechanical process

    Institute of Scientific and Technical Information of China (English)

    SHEN Jian(沈健); G.Gottstein

    2004-01-01

    The evolution of microstructural variables, including the densities of mobile dislocation, immobile dislocation at the cell interiors, immobile dislocation in the cell walls, as well as total dislocation density, of an Al-Mg-Si aluminium alloy during thermomechanical processing were simulated based on a three-internal-variables-model (3IVM) involving dislocation climb and interaction. Optimization was carried out to fit the calculated stress-strain curves to the experimental data of the Al-Mg-Si alloy with minimum mean deviation. Precipitations were taken into consideration of modeling. The stress-strain curves predicted by the kinetic equations of state in the 3IVM have a good agreement with the experimental data.

  12. Effect of heat treatment on the inhibition of the acidic corrosion aluminium alloy

    Energy Technology Data Exchange (ETDEWEB)

    Khamis, E. (Alexandria Univ. (Egypt). Dept. of Chemistry); El-Gamal, M. (Alexandria Univ. (Egypt). Dept. of Material Science); El-Toukhy, A. (Alexandria Univ. (Egypt). Dept. of Material Science); Atea, M. (Alexandria Univ. (Egypt). Dept. of Material Science)

    1994-12-01

    The effect of heat treatment on the inhibition of acid corrosion of duralumin has been studied using gasometry, mass loss measurements and potentiodynamic technique. All the data reveal that the duralumin generally developed good corrosion resistance after heat treatment and the corrosion rate ranked as follows: Non treated > Naturally aged > quenched. This improvement in the corrosion resistance was attributed to the structural homogeneity of the heat-treated alloys. The presence of some selected aryl and alkyl triazoline derivatives at the threshold concentration of 5 x 10[sup -3] M indicate that these compounds retard the corrosion rate of duralumin and the extent of inhibition depends on the molecular structure of the inhibitors. Polarization curves show that the triazoline compounds act as mixed-type inhibitors affecting both the cathodic and anodic processes. Moreover, there is no noticeable difference in the degree by which the triazoline derivatives inhibit the corrosion of pure aluminium and heat treated duralumin alloy. (orig.)

  13. Effects of different tempers on precipitation hardening of 6000 series aluminium alloys

    Institute of Scientific and Technical Information of China (English)

    LIU Hong; ZHAO Gang; LIU Chun-ming; ZUO Liang

    2007-01-01

    By means of Vickers hardness, mechanical property and formability tests, the effects of different tempers on precipitation hardening of 6000 series aluminium alloys for automotive body sheets were investigated. The results indicate that the short-time pre-aging at 170 ℃ makes for subsequent artificial aging precipitation hardening. With the increase of pre-aging time, the artificial aging hardenability increases. The aging hardening rate reaches the maximum when pre-aging time is up to 10 min, and then it decreases. The short-time pre-aging at 170 ℃ benefits sheets to obtain lower strength under delivery condition and consequently to improve stamping formability of automotive body sheets. The effects of different tempers on precipitation hardening are much more obvious than those of the alloying elements. It is a good treatment schedule to perform pre-aging for 5 min at 170 ℃ right after solution treatment.

  14. Effects of Moulding Sand Permeability and Pouring Temperatures on Properties of Cast 6061 Aluminium Alloy

    Directory of Open Access Journals (Sweden)

    Olawale Olarewaju Ajibola

    2015-01-01

    Full Text Available Effects of moulding sand permeabilities prepared from the combinations of four proportions of coarse and fine particle size mixtures and pouring temperatures varied from 700, 750, and 800 (±10°C were studied on the hardness, porosity, strength, and microstructure of cast aluminium pistons used in hydraulic brake master cylinder. Three sand moulds were prepared from each of the 80 : 20, 60 : 40, 40 : 60, and 20 : 80 ratios. The surfaces and microstructures of cast samples were examined using high resolution microscopic camera, metallurgical microscope with digital camera, and scanning electron microscope with EDX facilities. The best of the metallurgical properties were obtained from the combination of 80 : 20 coarse-fine sand ratio and 750 ± 10°C pouring temperature using as MgFeSi inoculant. An 8 : 25 ratio of coarse to fine grained eutectic aluminium alloy was obtained with enhanced metallographic properties. The cast alloy poured at 750 ± 1°C has a large number of fine grain formations assuming broom-resembling structures as shown in the 100 µm size SEM image.

  15. Optimisation of the rivet joints of the CFRP composite material and aluminium alloy

    Directory of Open Access Journals (Sweden)

    A. Czulak

    2007-01-01

    Full Text Available Purpose: The project included analysis of strain, cracking, and failure of riveted joints of plate elements madefrom the carbon-fibre-reinforced plastics (CFRP and from the 6061 aluminium alloy.Design/methodology/approach: The modelled static tensile strength test carried out for the plates from CFRPand from the 6061 aluminium alloy joined with the steel rivet. Computer simulation was carried out with IDEASsoftware package employing the FEM.Findings: Simulations using the mesh with a bigger number of FEM elements do not yield better accuracy ofcalculations and do not improve convergence with the results of laboratory experiments. Only the calculationtime gets longer. Computer simulation has also show that the type of contacts employed between elementsaffects the results significantly.Research limitations/implications: For the composite materials, joints between materials and computersimulation examinations are planed.Practical implications: Results obtained for the mesh with 4 and 5 FEM elements are the closest to the resultsof laboratory experiments, which is confirmed by the strain plot. Simulations using the mesh with a biggernumber of FEM elements do not yield better accuracy of calculations and do not improve convergence with theresults of laboratory experiments. Only the calculation time gets longer. Computer simulation has show that thetype of contacts employed between elements affects the results significantly.Originality/value: The paper presents influence of fibre mesh closeness on convergence of the results with laboratorytests. Simulation results were collected and compared with the laboratory static tensile strength tests results.

  16. On the origins of the anisotropic mechanical behaviour of extruded AA2017 aluminium alloy

    Indian Academy of Sciences (India)

    A MAY

    2017-04-01

    This paper presents some experimental investigations about the origins of the anisotropic behaviour in cyclic loadings of AA2017 aluminium alloy. In the first step, fatigue damage evolutions were quantified for controlled proportional cyclic loadings in axial and shear directions. In this stage, the aim was to confirm the anisotropic mechanical behaviour, which has recently been revealed. To this end, severalmodels of fatigue damage quantification were used. After a comparative study between the obtained results we confirmed the anisotropic nature of the used material. In the second step, microstructural investigations were performed in order to understand the origins of the anisotropic mechanical behaviour. We used scanning electron microscopy to analyse phases and precipitates inthe transversal and the longitudinal sections. It was deduced that the structure and the morphology of these entities are responsible for the anisotropic behaviour of the used aluminium alloy. Moreover, the results obtained usingKikushi diagrams, poles figure and inverse poles figures have also confirmed these conclusions. Indeed, these results have shown great differences in crystallographic texture of the material.

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

    Energy Technology Data Exchange (ETDEWEB)

    Zhuang, W., E-mail: wyman.zhuang@dsto.defence.gov.au [Aerospace Division, Defence Science and Technology Organisation, 506 Lorimer Street, Fishermans Bend, Victoria 3207 (Australia); Liu, Q.; Djugum, R.; Sharp, P.K. [Aerospace Division, Defence Science and Technology Organisation, 506 Lorimer Street, Fishermans Bend, Victoria 3207 (Australia); Paradowska, A. [Australian Nuclear Science and Technology Organisation, Lucas Heights, NSW 2232 (Australia)

    2014-11-30

    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.

  18. Investigating the Acid Failure of Aluminium Alloy in 2 M Hydrochloric Acid Using Vernonia amygdalina

    Directory of Open Access Journals (Sweden)

    Olugbenga A. Omotosho

    2012-04-01

    Full Text Available The acid failure of aluminium alloy in 2 M hydrochloric acid solution in the presence of Vernonia amygdalina extract was investigated using gasometric technique. Aluminium alloy coupons of dimension 4 cm by 1 cm were immersed in test solutions of free acid and also those containing extract volumes of 2, 3, 4 and 5 cm3 at ambient temperature for 30 minutes. The volumes of hydrogen gas evolved as a result of the rate of reaction were recorded and analyzed. Analysis revealed that maximum inhibitor efficiency which corresponds to the lowest corrosion rate was obtained at optimum inhibitor volumes of 5 cm3, with reduction in the corrosion rate observed to follow in order of increasing extract volumes. Adsorption study revealed that Temkin isotherm best described the metal surface interaction with the extract phytochemicals, with 12 minutes becoming the best exposure time for the phytochemicals to adsorb to the metal surface at all volumes. Statistical modelling of the corrosion rate yielded an important relationship suitable for estimating corrosion rate values once volumes of the extract is known. Microstructural studies, showed an indirect relationship between crack growth rates and extract volumes, while consistency of the irregular intermetallic phases increases with increasing extract volumes.

  19. International Foundry Forum 2006

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    @@ The International Foundry Forum is a "Summit"of the Foundry World. It is the convention of the CEO world wide, of important casting users, ferrous and non-ferrous foundries as well as foundry equipment and consumable suppliers. Their overall goal is to increase the market opportunities for metal castings in competition with other processes and products in a global business environment.

  20. Determination of aluminium in molybdenum and tungsten metals, iron, steel and ferrous and non-ferrous alloys with pyrocatechol violet.

    Science.gov (United States)

    Donaldson, E M

    1971-09-01

    A method for determining 0.001-0.10% of aluminium in molybdenum and tungsten metals is described. After sample dissolution, aluminium is separated from the matrix materials by chloroform extraction of its acetylacetone complex, at pH 6.5, from an ammonium acetate-hydrogen peroxide medium, then back-extracted into 12M hydrochloric add. Following separation of most co-extracted elements, except for beryllium and small amounts of chroinium(III) and copper(II), by a combined ammonium pyrrolidincdithiocarbamate-cupfen-on-chlorofonn extraction, aluminium is determined spectrophotometrically with Pyrocatechol Violet at 578 nm. Chromium interferes during colour development but beryllium, in amounts equivalent to the aluminium concentration, does not cause significant error in the results. Interference from copper(II) is eliminated by reduction with ascorbic acid. The proposed method is also applicable to iron, steel, ferrovanadium, and copper-base alloys after preliminary removal of the matrix elements by a mercury cathode separation.

  1. Implementation and Testing of Numerical Models for Evolution of Microchemistry and Microstructure During Back-Annealing of Aluminium Alloys

    OpenAIRE

    Iversen, Jørgen Tandberg

    2014-01-01

    Precipal and Alsoft are two separate models for simulating the effects of back-annealing on microchemistry and microstructure, respectively, in AA3xxx-type aluminium alloys (i.e Mn containing alloys). The precipitation model simulates the precipitation and growth of dispersoids, growth of constituents, and the resulting change in the solid solution concentration. Alsoft is a physical softening model which combines the effects of recovery and recrystallization.Precipal was originally implemen...

  2. Development of new alloys of commercial aluminium (2S) with zinc, indium, tin, and bismuth as anodes for alkaline batteries

    Science.gov (United States)

    Sheik Mideen, A.; Ganesan, M.; Anbukulandainathan, M.; Sarangapani, K. B.; Balaramachandran, V.; Kapali, V.; Venkatakrishna Iyer, S.

    Studies show that the addition of zinc to commercial aluminium increases both the corrosion rate and the open-circuit potential (OCP) in alkaline medium. The addition of indium gives rise to a ternary alloy that shows a slightly higher OCP and an appreciably reduced extent of self corrosion. Addition of bismuth results in a quaternary alloy whose corrosion rate is comparable with the ternary alloy, but the OCP is found to be higher. Anodic polarisation characteristics and anode efficiency are found to be in favour of quaternary alloys. Electrochemical studies with Al, Zn, Sn ternary alloys and Al, Zn, Sn, Bi quaternary alloy favours the choice of the latter as a galvanic anode. Among the two types of quaternary alloys, those containing indium, rather than tin, are found to be more suitable as alkaline battery anodes.

  3. Positron annihilation spectroscopy as a tool to develop self healing in aluminium alloys

    Energy Technology Data Exchange (ETDEWEB)

    Hautakangas, S.; Schut, H. [Faculty of Applied Physics, section NPM2, Delft University of Technology, Mekelweg 15, 2629 JB, Delft (Netherlands); Zwaag, S. van der; Rivera Diaz del Castillo, P.E.J. [Faculty of Aerospace Engineering, Section Fundamentals of Advanced Materials, Delft University of Technology, Kluyverweg 1, 2629 HS Delft (Netherlands); Dijk, N.H. van [Faculty of Applied Physics, Section FAME, Delft University of Technology, Mekelweg 15, 2629 JB, Delft (Netherlands)

    2007-07-01

    Positron lifetime and Doppler broadening spectroscopy have been applied to probe the free volume generation (vacancies, dislocations and nano-cracks) during plastic deformation of a commercial aluminium AA2024 (T3) alloy. Aim of the total program is to study how solute atoms can be driven to the areas where initial cracking may occur in order to prevent the failure of the specimen. The phenomenon of closing the nano-crack is called Self Healing, and can provide extra strength and ductility to the alloy under some loading conditions. Plastic deformation of over-aged aluminum alloy at room temperature increases the average positron lifetime from initial value of 190 ps to 203 ps. The low momentum parameter S increases in agreement with the increase of open volume defects. The elastic deformation of the sample does not have a recordable effect on the positron annihilation data. It is also shown that the induced damage does not recover after loading the sample, i.e. the AA2024 in the T3 state is non self healing material, as expected, providing important first state result in the research of self healing Al alloys. (copyright 2007 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim) (orig.)

  4. The effect of strain rate on the evolution of microstructure in aluminium alloys.

    Science.gov (United States)

    Leszczyńska-Madej, B; Richert, M

    2010-03-01

    Intensive deformations influence strongly microstructure. The very well-known phenomenon is the diminishing dimension of grain size by the severe plastic deformation (SPD) methods. The nanometric features of microstructure were discovered after the SPD deformation of various materials, such as aluminium alloys, iron and others. The observed changes depended on the kind of the deformed material, amount of deformation, strain rate, existence of different phases and stacking fault energy. The influence of the strain and strain rate on the microstructure is commonly investigated nowadays. It was found that the high strain rates activate deformation in shear bands, microbands and adiabatic shear bands. It was observed that bands were places of the nucleation of nanograins in the material deformed by SPD methods. In the work, the refinement of microstructure of the aluminium alloys influenced by the high strain rate was investigated. The samples were compressed by a specially designed hammer to the deformation of phi= 0/0.62 with the strain rate in the range of [Formula in text]. The highest reduction of microbands width with the increase of the strain was found in the AlCu4Zr alloy. The influence of the strain rate on the microstructure refinement indicated that the increase of the strain rate caused the reduction of the microbands width in the all investigated materials (Al99.5, AlCu4Zr, AlMg5, AlZn6Mg2.5CuZr). A characteristic feature of the microstructure of the compressed material was large density of the shear bands and microbands. It was found that the microbands show a large misorientation to the surrounds and, except Al99.5, the large density of dislocation.

  5. A silanol-based nanocomposite coating for protection of AA-2024 aluminium alloy

    Energy Technology Data Exchange (ETDEWEB)

    Gonzalez, E.; Pavez, J.; Azocar, I.; Zagal, J.H. [Departamento de Quimica de los Materiales, Facultad de Quimica y Biologia, Universidad de Santiago de Chile, Avenida Bernardo O' Higgins 3363, Casilla 40, Correo 33, Santiago (Chile); Zhou, X. [Corrosion and Protection Centre, School of Materials, University of Manchester, Manchester M13 9PL (United Kingdom); Melo, F. [Departamento de Fisica, Facultad de Ciencias, Universidad de Santiago de Santiago de Chile, Avenida Bernardo O' Higgins 3363, Santiago (Chile); Thompson, G.E. [Corrosion and Protection Centre, School of Materials, University of Manchester, Manchester M13 9PL (United Kingdom); Paez, M.A., E-mail: maritza.paez@usach.cl [Departamento de Quimica de los Materiales, Facultad de Quimica y Biologia, Universidad de Santiago de Chile, Avenida Bernardo O' Higgins 3363, Casilla 40, Correo 33, Santiago (Chile)

    2011-09-01

    Highlights: {center_dot} A new silanol-based hybrid coating has been synthesized. {center_dot} The incorporation of CeO{sub 2} and ZrO{sub 2} nanoparticles into the coating greatly improves the corrosion resistance of the coated aluminium alloy. {center_dot} The effectiveness of the coating is increasingly evident for long term exposure to the sodium chloride solution. {center_dot} The silanol-based nanocomposite coatings have self-healing ability. - Abstract: A new hybrid sol-gel type film, composed of tetraethylorthosilicate (TEOS) and tetraocthylorthosilicate (TEOCS), and modified with different nanoparticle systems, has been investigated as a coating for protection of AA-2024-T3 aluminium alloy. The nanoparticle systems considered were either ZrO{sub 2} or CeO{sub 2} or their combination{sub .} The zirconia nanoparticles were prepared from a Zr (IV) propoxide sol (TPOZ), using an organic stabilizer, and the CeO{sub 2} nanoparticles were developed spontaneously after adding cerium nitrate solution to the hybrid sol. The chemical composition and the structure of the hybrid sol-gel films were examined by X-ray photoelectron spectroscopy (XPS), scanning electron microscopy (SEM) and atomic force microscopy (AFM). The corrosion resistance of the coated AA-2024 alloy was examined by potentiodynamic polarization. The results revealed that, for short exposure times in the electrolyte, incorporation of ZrO{sub 2} or CeO{sub 2} nanoparticles in the hybrid film does not provide an increase in the corrosion resistance of the coated AA-2024 alloy. Further, the resistance was significantly reduced by increasing the nanoparticle content. Conversely, by incorporating both nanoparticles (ZrO{sub 2} and CeO{sub 2}), the corrosion resistance of the resulting hybrid films increased slightly. The behavior changed significantly when the coated alloy was exposed to the electrolyte for 5 days. The corrosion resistance of the coatings, unmodified and modified with CeO{sub 2} or Zr

  6. 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.

  7. Flux-free brazing of Mg-containing aluminium alloys by means of cold spraying

    Institute of Scientific and Technical Information of China (English)

    Kirsten BOBZIN; Lidong ZHAO; Felix ERNST; Katharina RICHARDT

    2008-01-01

    In the present study, AlSi12 and AlSi10Cu4 were deposited onto Mg-containing aluminium alloys 6063 and 5754 by cold spraying. The influences of the two brazing alloys and spray parameters on coating formation were investigated. The microstructure of the coatings was characterized. Some coated samples were heat-treated at 590℃ and 560℃ in air to investigate the effect of the rupture of oxide scales on the diffusion of elements during heat-treatment. Some coated samples were brazed under argon atmosphere without any fluxes. The results show that AlSi12 had much better deposition behaviour than AlSi10Cu4. Due to the rupture of oxide scales, Cu and Si diffused into the substrate and a metal-lurgical bond formed between the brazing alloys and the substrates during heat-treatment. The coated samples could be brazed without any fluxes. Because the oxide scales prevented the formation of a metallurgical bond locally, the brazed samples had relatively low shear strengths of up to 43 MPa.

  8. Influence of friction stir welding parameters on properties of 2024 T3 aluminium alloy joints

    Directory of Open Access Journals (Sweden)

    Eramah Abdsalam M.

    2014-01-01

    Full Text Available The aim of this work is to analyse the process of friction stir welding (FSW of 3mm thick aluminium plates made of high strength aluminium alloy - 2024 T3, as well as to assess the mechanical properties of the produced joints. FSW is a modern procedure which enables joining of similar and dissimilar materials in the solid state, by the combined action of heat and mechanical work. This paper presents an analysis of the experimental results obtained by testing the butt welded joints. Tensile strength of the produced joints is assessed, as well as the distribution of hardness, micro-and macrostructure through the joints (in the base material, nugget, heat affected zone and thermo-mechanically affected zone. Different combinations of the tool rotation speed and the welding speed are used, and the dependence of the properties of the joints on these parameters of welding technology is determined. [Projekat Ministarstva nauke Republike Srbije, br. TR 34018 i br. TR 35006

  9. Mechanical spectroscopy of thermal stress relaxation in aluminium alloys reinforced with short alumina fibres

    Energy Technology Data Exchange (ETDEWEB)

    Carreno-Morelli, E.; Schaller, R. [Ecole Polytechnique Federale, Lausanne (Switzerland). Inst. de Genie Atomique; Urreta, S.E.

    1998-05-01

    The mechanical behaviour under low temperature thermal cycling of aluminium-based composites reinforced with short Al{sub 2}O{sub 3} SAFFIL fibres has been investigated by mechanical spectroscopy (mechanical loss and elastic shear modulus measurements). A mechanical loss maximum has been observed during cooling which originates in the relaxation of thermal stresses at the interfaces due to the differential thermal expansion between matrix and reinforcement. The maximum height increases with the volumetric fibre content. In addition, if the matrix strength is increased by the appropriated choice of alloy and thermal treatment, the maximum diminishes and shifts to lower temperatures. No damage accumulation at the interfaces has been detected during long period thermal cycling in the range 100 to 500 K. A description of the damping behaviour is made in terms of the development of microplastic zones which surround the fibres. (orig.) 9 refs.

  10. QUANTIFICATION OF SHEAR DAMAGE EVOLUTION IN ALUMINIUM ALLOY 2024T3

    Institute of Scientific and Technical Information of China (English)

    Tang Chak-yin; Fan Jianping; Tsui Chi-pong; Lee Tai-chiu; Chan Luen-chow; Rao Bin

    2007-01-01

    Shear damage may occur in the process of metal machining such as blanking and cutting, where localized shear deformation is developed. Experimental findings indicate that microscopic shear damage evolution in aluminium alloy 2024T3 (Al 2024T3) is a multi-stage mechanism, including particle cracking, micro-shear banding, matrix microcracking and coalescence of microcracks. This study is an attempt to use a set of equations to describe the multi-stage shear damage evolution in Al 2024T3. The shear damage variables in terms of multi-couple parameters of a power-law hardening material have been defined. An evolution curve of shearing damage has been calculated from experimental data. The values of the shear damage variable at different stages of damage have also been calculated. By making use of the findings, the relation between the microscopic shear damage evolution and the macroscopic shear response of the material has been discussed.

  11. Plastic anisotropy of ultrafine grained aluminium alloys produced by accumulative roll bonding

    Energy Technology Data Exchange (ETDEWEB)

    Beausir, B., E-mail: benoit.beausir@univ-metz.fr [Institut fuer Strukturphysik, Technische Universitaet Dresden, D-01062 Dresden (Germany); Scharnweber, J. [Institut fuer Strukturphysik, Technische Universitaet Dresden, D-01062 Dresden (Germany); Jaschinski, J. [Institut fuer Leichtbau und Kunststofftechnik, Technische Universitaet Dresden, D-01062 Dresden (Germany); Brokmeier, H.-G. [GKSS Forschungszentrum, Max-Planck-Strasse, D-21494 Geesthacht (Germany); Oertel, C.-G.; Skrotzki, W. [Institut fuer Strukturphysik, Technische Universitaet Dresden, D-01062 Dresden (Germany)

    2010-05-25

    The plastic anisotropy of ultrafine grained aluminium alloys AA1050 and AA6016 produced by accumulative roll bonding (ARB) has been investigated by tensile deformation via the Lankford parameter. The average normal and planar anisotropies slightly increase (from 0.6 to 0.9) and decrease (from 0.6 to -0.7) as a function of ARB cycles, respectively. The global textures measured by neutron diffraction are used to simulate the Lankford and anisotropy parameters of the plates after 0, 2, 4, 6 and 8 ARB cycles with the help of the viscoplastic polycrystal self-consistent model. Simulation results are compared with those from experiment and discussed with regard to texture, strain rate sensitivity, grain shape and slip system activity.

  12. Optimization of process parameters in CNC turning of aluminium alloy using hybrid RSM cum TLBO approach

    Science.gov (United States)

    Rudrapati, R.; Sahoo, P.; Bandyopadhyay, A.

    2016-09-01

    The main aim of the present work is to analyse the significance of turning parameters on surface roughness in computer numerically controlled (CNC) turning operation while machining of aluminium alloy material. Spindle speed, feed rate and depth of cut have been considered as machining parameters. Experimental runs have been conducted as per Box-Behnken design method. After experimentation, surface roughness is measured by using stylus profile meter. Factor effects have been studied through analysis of variance. Mathematical modelling has been done by response surface methodology, to made relationships between the input parameters and output response. Finally, process optimization has been made by teaching learning based optimization (TLBO) algorithm. Predicted turning condition has been validated through confirmatory experiment.

  13. Hot-crack test for aluminium alloys welds using TIG process

    Directory of Open Access Journals (Sweden)

    Deschaux-beaume F.

    2010-06-01

    Full Text Available Hot cracking is a critical defect frequently observed during welding of aluminium alloys. In order to better understand the interaction between cracking phenomenon, process parameters, mechanical factors and microstructures resulting from solidification after welding, an original hot-cracking test during welding is developed. According to in-situ observations and post mortem analyses, hot cracking mechanisms are investigated, taking into account the interaction between microstructural parameters, depending on the thermal cycles, and mechanical parameters, depending on geometry and clamping conditions of the samples and on the thermal field on the sample. Finally, a process map indicating the limit between cracking and non-cracking zones according to welding parameters is presented.

  14. Multi response optimization of wire-EDM process parameters of ballistic grade aluminium alloy

    Directory of Open Access Journals (Sweden)

    Ravindranadh Bobbili

    2015-12-01

    Full Text Available In the current investigation, a multi response optimization technique based on Taguchi method coupled with Grey relational analysis is planned for wire-EDM operations on ballistic grade aluminium alloy for armour applications. Experiments have been performed with four machining variables: pulse-on time, pulse-off time, peak current and spark voltage. Experimentation has been planned as per Taguchi technique. Three performance characteristics namely material removal rate (MRR, surface roughness (SR and gap current (GC have been chosen for this study. Results showed that pulse-on time, peak current and spark voltage were significant variables to Grey relational grade. Variation of performance measures with process variables was modelled by using response surface method. The confirmation tests have also been performed to validate the results obtained by Grey relational analysis and found that great improvement with 6% error is achieved.

  15. Microstructure of friction stir welded joints of 2017A aluminium alloy sheets.

    Science.gov (United States)

    Mroczka, K; Dutkiewicz, J; Pietras, A

    2010-03-01

    The present study examines a friction stir welded 2017A aluminium alloy. Transmission electron microscope investigations of the weld nugget revealed the average grain size of 5 microm, moderate density of dislocations as well as the presence of nanometric precipitates located mostly in grains interiors. Scanning electron microscope observations of fractures showed the presence of ductile fracture in the region of the weld nugget with brittle precipitates in the lower part. The microhardness analysis performed on the cross-section of the joints showed fairly small changes; however, after the artificial ageing process an increase in hardness was observed. The change of the joint hardness subject to the ageing process indicates partial supersaturation in the material during friction stir welding and higher precipitation hardening of the joint.

  16. Flow and failure of an aluminium alloy from low to high temperature and strain rate

    Directory of Open Access Journals (Sweden)

    Sancho Rafael

    2015-01-01

    Full Text Available The mechanical behaviour of an aluminium alloy is presented in this paper. The study has been carried out to analyse the flow and failure of the aluminium alloy 7075-T73. An experimental study has been planned performing tests of un-notched and notched tensile specimens at low strain rates using a servo-hydraulic machine. High strain rate tests have been carried out using the same geometry in a Hopkinson Split Tensile Bar. The dynamic experiments at low temperature were performed using a cryogenic chamber, and the high temperature ones with a furnace, both incorporated to the Hopkinson bar. Testing temperatures ranged from − 50 ∘C to 100 ∘C and the strain rates from 10−4 s−1 to 600 s−1. The material behaviour was modelled using the Modified Johnson-Cook model and simulated using LS-DYNA. The results show that the Voce type of strain hardening is the most accurate for this material, while the traditional Johnson-Cook is not enough accurate to reproduce the necking of un-notched specimens. The failure criterion was obtained by means of the numerical simulations using the analysis of the stress triaxiality versus the strain to failure. The diameters at the failure time were measured using the images taken with an image camera, and the strain to failure was computed for un-notched and notched specimens. The numerical simulations show that the analysis of the evolution of the stress triaxiality is crucial to achieve accurate results. A material model using the Modified Johnson-Cook for flow and failure is proposed.

  17. Influences of post weld heat treatment on tensile properties of friction stir welded AA2519-T87 aluminium alloy joints

    Science.gov (United States)

    Sabari, S. Sree; Balasubramanian, V.; Malarvizhi, S.; Reddy, G. Madusudhan

    2015-12-01

    AA 2519-T87 is an aluminium alloy that principally contains Cu as an alloying element and is a new grade of Al-Cu alloy system. This material is a potential candidate for light combat military vehicles. Fusion welding of this alloy leads to hot cracking, porosity and alloy segregation in the weld metal region. Friction stir welding (FSW) is a solid state joining process which can overcome the above mentioned problems. However, the FSW of age hardenable aluminium alloys results in poor tensile properties in the as-welded condition (AW). Hence, post weld heat treatment (PWHT) is used to enhance deteriorated tensile properties of FSW joints. In this work, the effect of PWHT, namely artificial ageing (AA) and solution treatment (ST) followed by ageing (STA) on the microstructure, tensile properties and microhardness were systematically investigated. The microstructural features of the weld joints were characterised using an optical microscope (OM), scanning electron microscope (SEM) and transmission electron microscope (TEM). The tensile strength and microhardness of the joints were correlated with the grain size, precipitate size, shape and its distribution. From the investigation, it was found that STA treatment is beneficial in enhancing the tensile strength of the FSW joints of AA2519-T87 alloy and this is mainly due to the presence of fine and densely distributed precipitates in the stir zone.

  18. Analytical and Experimental Investigation for Tensile and Compressive Creep of the A3003P Aluminium Alloy Used for Plate-Fin Heat Exchanger

    National Research Council Canada - National Science Library

    EL-SHENNAWY, Mohamed; MORITA, Yoshiyasu; KOUSO, Masashi

    1999-01-01

    Analytical and experimental analysis for tensile and compressive creep properties of fine and coarse-grained aluminium alloy, A3003P, used for plate-fin heat exchanger are presented for temperatures from 400°C to 600...

  19. Microstructure and high temperature stability of age hardenable AA2219 aluminium alloy modified by Sc, Mg and Zr additions

    Energy Technology Data Exchange (ETDEWEB)

    Naga Raju, P. [Metallurgical and Materials Engineering Department, IIT-Madras, Chennai 600036 (India)], E-mail: puvvala_nagaraju@yahoo.com; Srinivasa Rao, K. [Metallurgical Engineering Department, Andhra University, Visakapatnam 530003 (India); Reddy, G.M. [Defence Metallurgical Research Laboratory, Hyderabad 500258 (India); Kamaraj, M.; Prasad Rao, K. [Metallurgical and Materials Engineering Department, IIT-Madras, Chennai 600036 (India)

    2007-08-25

    The present work pertains to the improvement of high temperature stability of age hardenable AA2219 aluminium-copper (6.3%) alloy. Addition of scandium, magnesium and zirconium to the base metal AA2219 was adopted to improve this high temperature stability. These additions were systematically varied by preparing alloys of different composition using gas tungsten arc melting. Long time ageing studies and impression creep technique were used to study the high temperature stability of the alloys. These modified compositions of the alloy resulted in fine equiaxed grains, refined eutectics, large number of high temperature stable and finer precipitates. Among all the compositions, 0.8% Sc + 0.45% Mg + 0.2% Zr addition was found to be significant in improving the high temperature stability of AA2219 alloy. This may be attributed to the possible microstructural changes, solute enrichment of the matrix and pinning of the grain boundaries by the finer precipitates.

  20. Material modelling and its application to creep-age forming of aluminium alloy 7B04

    Directory of Open Access Journals (Sweden)

    Lam Aaron C.L.

    2015-01-01

    Full Text Available Creep-ageing behaviour of aluminium alloy 7B04-T651 at 115 °C under a range of tensile stress levels has been experimentally investigated and numerically modelled for creep-age forming (CAF applications. Creep strain, yield strength evolution and precipitate growth of creep-aged specimens were investigated. The alloy was modelled using a set of unified constitutive equations, which captures its creep deformation and takes into account yield strength contributions from three creep-age hardening mechanisms. Applications of the present work are demonstrated by implementing the determined material model into a commercial finite element analysis solver to analyse CAF operations carried out in a novel flexible CAF tool. Stress relaxation, yield strength, precipitate size and springback were predicted for the creep-age formed plates. The predicted springback were further quantified and compared with experimental measurements and a good agreement of 2.5% deviation was achieved. This material model now enables further investigations of 7B04 under various CAF scenarios to be conducted inexpensively via computational modelling.

  1. Surface nanocrystallization of 7A04 aluminium alloy induced by circulation rolling plastic deformation

    Institute of Scientific and Technical Information of China (English)

    YE Hui-qiong; FAN Xin-min

    2006-01-01

    The surface nanocrystalline microstructures of 7A04 aluminium alloy was obtained by means of circulation rolling plastic deformation(CRPD),the grain refinement behavior and the hardness variation were examined. X-ray diffraction(XRD) and transmission electron microscopy(TEM) were applied to characterize the microstructure of the surface layer. The experimental evidences show that,after the CRPD treatment,the mean grain size in the surface layer is about 50 nm. The microhardness of the nanostructured surface layers is enhanced significantly after CRPD compared with that of the matrix,which can be attributed primarily to the grain refinement. The microhardness at the top surface can reach about HV0.05335,while the value of the matrix is HV0.05160 or so. The surface hardening effect is obtained obviously. Besides,the thermal stability of nanocrystalline layer was investigated. The results of the XRD analysis and the microhardness measurement show that the nanocrystalline layer has better thermal-stability than the matrix. And the DSC measurement shows that the synthesis of nanostructured surface layer has influence on the phase transformation of 7A04 aluminum alloy.

  2. Oxide growth on aluminium alloys in the presence of ammonium fluoborate

    Energy Technology Data Exchange (ETDEWEB)

    Oliver, J.; Paterson, P.; Flavell, T. [Royal Melbourne Inst. of Tech., VIC (Australia); Biddle, G. [Alcoa Rolled Products (Australia)

    1996-12-31

    The aim of this study as to determine the mechanisms involved in using ammonium fluoborate as a reducing atmosphere when preheating a high magnesium content aluminium alloy. Rutherford Backscattering (RBS) has been the major technique used in the analysis of samples, it revealed significant reduction in both the diffusion of magnesium to the surface and the calculated oxide thickness in the presence of NH{sub 4}BF{sub 4}. At temperatures above 500 deg C in air, SEM images revealed depressions and voids due to incipient melting at various stages, around the grain boundaries. Grain boundaries effectively acted as pipes aiding the diffusion of magnesium to the surface. These results have been verified through compositional analysis with both RBS and auger electron spectroscopy (AES). Results from NH{sub 4}BF{sub 4} atmosphere preheat conditions showed significant improvements. It was verified experimentally that above 500 deg C , AA5182 alloys undergo incipient melting at the grain boundaries with magnesium diffusing through to the surface. 5 refs., 1 fig.

  3. Effects of homogenisation treatment on microstructure and hot ductility of aluminium alloy 6063

    Energy Technology Data Exchange (ETDEWEB)

    Couto, K.B.S.; Claves, S.R.; Geetruyden, W.H. van; Misiolek, W.Z.; Goncalves, M.

    2005-02-15

    Several homogenisation treatments were applied to direct chill (DC) cast ingots of aluminium alloy 6063, in order to analyse the resulting microstructures developed from these diverse conditions and their effects on the hot ductility of this alloy. Imaging was performed using scanning electron microscopy (SEM) and a focused ion beam (FIB) instrument. These techniques identified variations in distribution and morphology of second phase particles (AlFeSi and Mg{sub 2}Si). FIB results for the various AlFeSi particles correctly identify their shapes in three dimensions (3D). The particles were identified by energy dispersive spectroscopy (EDS) in the SEM, and by X-ray diffraction (XRD) for bulk samples. Hot tensile testing (HTT) was conducted between 470 and 600 deg C to asses the hot ductility for each condition. The inferior ductility of as cast samples was due to the poor bond strength of the {beta} AlFeSi phase at the grain boundaries. Homogenised samples, which contain {alpha} AlFeSi, exhibited improved ductility. Samples that were water quenched following homogenisation were absent of Mg{sub 2}Si precipitates, when these elements remained in solid solution. These exhibited the highest ductility. (Author)

  4. Modified Layer-Removal Method for Measurement of Residual Stress in Pre-stretched Aluminium Alloy Plate

    Institute of Scientific and Technical Information of China (English)

    Liangbao Liu; Jianfei Sun; Wuyi Chen; Pengfei Sun

    2015-01-01

    Residual stress is one of the factors affecting the machining deformation of monolithic structure parts in the aviation industry. Thus, the studies on machining deformation rules induced by residual stresses largely depend on correctly and efficiently measuring the residual stresses of workpieces. A modified layer⁃removal method is proposed to measure residual stress by analysing the characteristics of a traditional layer⁃removal method. The coefficients of strain release are then deduced according to the simulation results using the finite element method ( FEM) . Moreover, the residual stress in a 7075T651 aluminium alloy plate is measured using the proposed method, and the results are then analyzed and compared with the data obtained by the traditional methods. The analysis indicates that the modified layer⁃removal method is effective and practical for measuring the residual stress distribution in pre⁃stretched aluminium alloy plates.

  5. Comparison of RSM with ANN in predicting tensile strength of friction stir welded AA7039 aluminium alloy joints

    Institute of Scientific and Technical Information of China (English)

    A. K. LAKSHMINARAYANAN; V. BALASUBRAMANIAN

    2009-01-01

    Friction stir welding(FSW) is an innovative solid state joining technique and has been employed in aerospace, rail, automotive and marine industries for joining aluminium, magnesium, zinc and copper alloys. The FSW process parameters such as tool rotational speed, welding speed, axial force, play a major role in deciding the weld quality. Two methods, response surface methodology and artificial neural network were used to predict the tensile strength of friction stir welded AA7039 aluminium alloy. The experiments were conducted based on three factors, three-level, and central composite face centered design with full replications technique, and mathematical model was developed. Sensitivity analysis was carried out to identify critical parameters. The results obtained through response surface methodology were compared with those through artificial neural networks.

  6. Insight of the interface of electroless Ni-P/SiC composite coating on aluminium alloy, LM24

    OpenAIRE

    2015-01-01

    Electroless nickel composite coatings with silicon carbide, SiC, as reinforcing particles deposited with Ni–P onto aluminium alloy, LM24, having zincating as under layer were subjected to heat treatment using air furnace. The changes at the interface were investigated using scanning electron microscope (SEM) and energy dispersive X-ray (EDX) to probe the chemistry changes upon heat treatment. Microhardness tester with various loads using both Knoop and Vickers indenters was used to study the ...

  7. Probabilistic thermal-mechanical fatigue criterion for lost foam casting aluminium alloys based on 2D/3D porosities distribution

    OpenAIRE

    Szmytka F.; Limodin N.; Wang L; Osmond P.; Adrien J.; Charkaluk E.; Buffiere J.Y.

    2014-01-01

    A thermal-mechanical fatigue criterion is proposed to assess the lifetime of aluminium alloys produced by a lost foam casting process. It is based on the observed size distribution of pores sizes which are considered as critical zones for cracks initiation and gives reliable results when both pores sizes are identified from X-ray tomography and mean stresses are taken into account. Lifetime probabilities are finally successfully compared with experimental results.

  8. Probabilistic thermal-mechanical fatigue criterion for lost foam casting aluminium alloys based on 2D/3D porosities distribution

    Directory of Open Access Journals (Sweden)

    Szmytka F.

    2014-06-01

    Full Text Available A thermal-mechanical fatigue criterion is proposed to assess the lifetime of aluminium alloys produced by a lost foam casting process. It is based on the observed size distribution of pores sizes which are considered as critical zones for cracks initiation and gives reliable results when both pores sizes are identified from X-ray tomography and mean stresses are taken into account. Lifetime probabilities are finally successfully compared with experimental results.

  9. Influence of welding speed on corrosion behaviour of friction stir welded AA5086 aluminium alloy

    Institute of Scientific and Technical Information of China (English)

    Kamran Amini; Farhad Gharavi

    2016-01-01

    The plates of AA5086 aluminium alloy were joined together by friction stir welding at a fixed rotation speed of 1000 r/min various welding speeds ranging from 63 to 100 mm/min. Corrosion behavior of the parent alloy (PA), the heat affected zone (HAZ), and the weld nugget zone (WNZ) of the joints were studied in 3.5% (mass fraction) aerated aqueous NaCl solution by potentiodynamic polarization and electrochemical impedance spectroscopy (EIS). The corrosion susceptibility of the weldments increases when the welding speed increases to 63 and 100 mm/min. However, the value of corrosion rate in the weldments is lower than that in the PA. Additionally, the corrosion current density increases with increasing the welding speed in the HAZ and the WNZ. On the contrary, the corrosion potential in the WNZ appears more positive than in the HAZ with decreasing the welding speed. The WNZ exhibits higher resistance compared to the HAZ and the PA as the welding speed decreases. The results obtained from the EIS measurements suggest that the weld regions have higher corrosion resistance than the parent alloy. With increasing the welding speed, the distribution and extent of the corroded areas in the WNZ region are lower than those of the HAZ region. In the HAZ region, in addition to the pits in the corroded area, some cracks can be seen around the corroded areas, which confirms that intergranular corrosion is formed in this area. The alkaline localized corrosion and the pitting corrosion are the main corrosion mechanisms in the corroded areas within the weld regions. Crystallographic pits are observed within the weld regions.

  10. Study of the Fatigue Life and Weight Optimization of an Automobile Aluminium Alloy Part under Random Road Excitation

    Directory of Open Access Journals (Sweden)

    A. Saoudi

    2010-01-01

    Full Text Available Weight optimization of aluminium alloy automobile parts reduces their weight while maintaining their natural frequency away from the frequency range of the power spectral density (PSD that describes the roadway profile. We present our algorithm developed to optimize the weight of an aluminium alloy sample relative to its fatigue life. This new method reduces calculation time; It takes into account the multipoint excitation signal shifted in time, giving a tangle of the constraint signals of the material mesh elements; It also reduces programming costs. We model an aluminium alloy lower vehicle suspension arm under real conditions. The natural frequencies of the part are inversely proportional to the mass and proportional to flexural stiffness, and assumed to be invariable during the process of optimization. The objective function developed in this study is linked directly to the notion of fatigue. The method identifies elements that have less than 10% of the fatigue life of the part's critical element. We achieved a weight loss of 5 to 11% by removing the identified elements following the first iteration.

  11. The effect of palm kernel shell ash on the mechanical properties of as-cast aluminium alloy matrix composites

    Directory of Open Access Journals (Sweden)

    Isiaka Oluwole OLADELE

    2016-06-01

    Full Text Available The present work describes the effect of palm kernel shell ash (PKSA as reinforcement on the mechanical properties of As-cast aluminium alloy. Recycled aluminium alloy from cylinder of an automotive engine block was degreased by using premium motor spirit (PMS also known as petrol, washed thoroughly with soap and water and sun dried for 5 days. The palm kernel shell was screened of dirt and other unwanted foreign materials before being roasted in furnace. The ash was further pulverized by laboratory ball mill machine followed by sieving to obtain particle sizes of 106 µm and divided into two parts. One portion was treated with NaOH solution while the other part was left as untreated before they are used to reinforced molten aluminium alloy in predetermined proportions. The newly developed composites were characterized with respect to their mechanical properties in response to the tests that were carried out on them. The results indicate that palm kernel shell ash can be used as potential reinforcing material for automobile applications.

  12. Optimizing pulsed current gas tungsten arc welding parameters of AA6061 aluminium alloy using Hooke and Jeeves algorithm

    Institute of Scientific and Technical Information of China (English)

    S. BABU; T. SENTHIL KUMAR; V. BALASUBRAMANIAN

    2008-01-01

    Though the preferred welding process to weld aluminium alloy is frequently constant current gas tungsten arc welding (CCGTAW), it resulted in grain coarsening at the fusion zone and heat affected zone(HAZ). Hence, pulsed current gas tungsten arc welding(PCGTAW) was performed, to yield finer fusion zone grains, which leads to higher strength of AA6061 (Al-Mg-Si) aluminium alloy joints. In order to determine the most influential control factors which will yield minimum fusion zone grain size and maximum tensile strength of the joints, the traditional Hooke and Jeeves pattern search method was used. The experiments were carried out based on central composite design with 31 runs and an algorithm was developed to optimize the fusion zone grain size and the tensile strength of pulsed current gas tungsten arc welded AA6061 aluminium aUoy joints. The results indicate that the peak current (Ip) and base current (IB) are the most significant parameters, to decide the fusion zone grain size and the tensile strength of the AA6061 aluminum alloy joints.

  13. Evaluation of the mechanical properties and corrosion behaviour of coconut shell ash reinforced aluminium (6063 alloy composites

    Directory of Open Access Journals (Sweden)

    Oluyemi O. DARAMOLA

    2015-12-01

    Full Text Available Aluminium 6063/Coconut shell ash (CSAp composites having 3-12 weight percent (wt% coconut shell ash were fabricated by double stir-casting method. The microstructure, ultimate tensile strength, hardness values, density and corrosion behaviour in 0.3M H2SO4 and 3.5wt% NaCl solution of the composites were evaluated. The density of the composites exhibit a linear and proportional decreased as the percentage of coconut shell ash increases in the aluminium alloy. It implies that composites with lower weight component can be produced by adding CSAp. The microstructural analysis showed uniform distribution of coconut shell ash particles in the aluminium alloy matrix. Significant improvement in hardness and ultimate tensile strength values was noticeable as the wt% of the coconut shell ash increased in the alloy, although this occur at the expense of ductility of the composites as the modulus of elasticity of the composites decreases as the percentage of CSAp increases. Hence, this work has established that incorporation of coconut shell particles in aluminum matrix can lead to the production of low cost aluminum composites with improved hardness and tensile strength values.

  14. Investigation of the T4 and T6 heat treatment cycles of semi-solid processed aluminium alloy A356

    CSIR Research Space (South Africa)

    Moller, H

    2008-01-01

    Full Text Available and T6 heat treatment cycles of semi- solid processed aluminium alloy A356 H. Möller*,1, G. Govender1 and W.E. Stumpf2 1Materials Science and Manufacturing, CSIR, Pretoria, 0001, South Africa 2Materials Science and Metallurgical Engineering... treatments. It is shown that a decrease of the solution treatment time at 540oC from 6 hours to 1 hour does not alter the T4 or T6 tensile properties of the SSM processed A356 alloy. Slightly better impact properties are obtained with the shorter solution...

  15. Sintering behaviour of Alumix 321 and 6061 aluminium alloys; Sinterizacion de las aleaciones Alumix 321 y 6061

    Energy Technology Data Exchange (ETDEWEB)

    Romano, P.; Fogagnolo, J. B.; Garcia, A.; Ruiz-Navas, E. M.

    2005-07-01

    The sintering behaviour of two aluminium alloys, Alumix 321 and 6061, was studied in this paper. Both have a similar Mg, Cu and Si contents, but have been obtained by different methods. the Alumix 321 alloy is produced by mixing the initial elements as powders and the 6061 is obtained by water atomization. The work carried out includes the study of the green properties, the determination of the compressibility and green strength curves as well as the microstructural characterization of the powders. Thermal analyses (DTAs and Dilatometries) were performed in order to study the behaviour of both alloys with temperature. furthermore, different sintering temperatures were studied by characterizing the mechanical properties of the sintered materials. It can be concluded that the 6061 alloys has better properties than the Alumix 321, when both were sintered at 600 degree centigree. (Author) 27 refs.

  16. Analysis of the solidification and microstructure of two aluminium alloys reinforced with TiB{sub 2} particles

    Energy Technology Data Exchange (ETDEWEB)

    Egizabal, Pedro; Garcia de Cortazar, Maider [Fundacion Inasmet E-20009 Donostia-San Sebastian (Spain); Torregaray, Amaia [University of Basque Country UPV/EHU E-48012, Bilbo-Bilbao (Spain); Veillere, Amelie; Silvain, Jean-Francois [CNRS, Universite de Bordeaux, ICMCB 87 Avenue du Docteur Albert Schweitzer, 33608 Pessac (France); Douin, Joel [CEMES-CNRS 29 Rue Jeanne Marvig, BP 94347, 31055 Toulouse Cedex 4 (France)

    2011-09-15

    Two aluminium alloys with 6 wt% TiB{sub 2} particles are studied for applications where increased wear resistance and mechanical strength at high temperature are required. The incorporation of hard ceramic particles has a strong influence on the microstructure and properties of the alloys. TiB{sub 2} particles play an important role in the nucleation of the different phases of the alloys during solidification, and in the reduction of grain size and porosity. The solidification patterns of Al-Si{sub 7}Mg{sub 0.3} + TiB{sub 2} (6 wt%) and Al-Cu{sub 5}MgTi+TiB{sub 2} (6 wt%) materials are compared to their corresponding non-reinforced alloys, and the microstructures are analyzed. (Copyright copyright 2011 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)

  17. Elastic and plastic properties of iron-aluminium alloys. Special problems raised by the brittleness of alloys of high aluminium content; Proprietes elastiques et plastiques des alliages fer-aluminium. Problemes particuliers poses par la fragilite des alliages a forte teneur en aluminium

    Energy Technology Data Exchange (ETDEWEB)

    Mouturat, P. [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires

    1966-06-01

    The present study embodies the results obtained with iron-aluminium alloys whose composition runs from 0 to nearly 50 atoms per cent aluminium. Conditions of elaboration and transformation have been studied successively, as well as the Young's modulus and the flow stress; the last chapter embodies, a study of the Portevin-le-Chatelier effect in alloys of 40 atoms per cent of aluminium. I) The principal difficulty to clear up consisted in the intergranular brittleness of ordered alloys; this brittleness has been considerably reduced with appropriate conditions of elaboration and transformation. II) The studies upon the Young's modulus are in connection with iron-aluminium alloys; transformation temperatures are well shown up. The formation of covalent bonds on and after 25 atoms per cent show the highest values of the modulus. III) The analysis of variations of the flow stress according to the temperature show some connection with ordered structures, the existence of antiphase domains and the existence of sur-structure dislocations. IV) In the ordered Fe Al domain the kinetics of the Portevin-le-Chatelier effect could be explained by a mechanism of diffusion of vacancies. The role they play has been specified by the influence they exert upon the dislocations; this has led us to the inhomogeneous Rudman order; this inhomogeneous order could explain the shape of the traction curves. (author) [French] Cette etude comporte les resultats obtenus avec des alliages fer-aluminium dont la composition s'etend de 0 a pres de 50 atomes pour cent d'aluminium. Nous avons etudie successivement les conditions d'elaboration et de transformation, le module elastique et la limite elastique; un dernier chapitre est consacre a l'etude du phenomene Portevin-le-Chatelier dans les alliages a 40 atomes pour cent d'aluminium. I) La principale difficulte a resoudre residait dans la fragilite intergranulaire des alliages ordonnes; celle-ci a ete

  18. The effect of natural pre-ageing on the mechanical properties of Rheo-High pressure die cast aluminium alloy 2139

    CSIR Research Space (South Africa)

    Chauke, L

    2015-07-01

    Full Text Available -high pressure die casting process (R-HPDC). Alloy 2139 is a Ag-containing aluminium alloy from the Al-Cu-Mg 2xxx series family. The addition of Ag enhances the age hardening response through the formation of co-clusters that act as precursors to the formation...

  19. Anodisation of Aluminium Alloys by Micro-Capillary Technique as a Tool for Reliable, Cost-Efficient, and Quick Process Parameter Determination

    Directory of Open Access Journals (Sweden)

    Daniela Nickel

    2016-01-01

    Full Text Available Anodisation is essential for improving surface properties of aluminium alloys and composites regarding wear and corrosion behaviour. Optimisation of the anodising process depends on microstructural constituents contained in aluminium alloys and represents a key task, consisting of the control of process parameters and electrolyte formulation. We applied the micro-capillary technique known from corrosion studies and modified it to form anodic aluminium oxide films on high-strength aluminium alloys in comparison to pure aluminium in sulphuric acid. A glass capillary with an opening of 800 μm in diameter was utilized. Corresponding electrochemical measurements during potentiodynamic and potentiostatic anodisation revealed anodic current responses similar to conventional anodisation. The measurement of film thickness was adapted to the thin anodised spots using ellipsometry and energy dispersive X-ray analysis. Cross sections prepared by focused ion beam milling confirm the thickness results and show the behaviour of intermetallic phases depending on the anodising potential. Consequently, micro-capillary anodising proved to be an effective tool for developing appropriate anodisation conditions for aluminium alloys and composites because it allows quick variation of electrolyte composition by applying low electrolyte volumes and rapid film formation due to short process durations at small areas and more flexible variation of process parameters due to the used set-up.

  20. EVALUATION OF PARAMETERS OF FRICTION STIR WELDING FOR ALUMINIUM AA6351 ALLOY

    Directory of Open Access Journals (Sweden)

    AHMED KHALID HUSSAIN

    2010-10-01

    Full Text Available Friction Stir Welding (FSW is a solid state welding process in which the relative motion between the tool and the work piece produces heat which makes the material of two edges being joined by plastic atomicdiffusion. This method relies on the direct conversion of mechanical energy to thermal energy to form the weld without the application of heat from conventional source. The rotational speed of the tools, the axial pressure and welding speed and the (weld time are the principal variables that are controlled in order to provide the necessary combination of heat and pressure to form the weld. These parameters are adjusted so that the interface is heated into the plastic temperature range (plastic state where welding can take place. During the last stage of welding process, atomic diffusion occurs while the interfaces are in contact, allowing metallurgical bond to form between the two materials. The functional behaviour of the weldments is substantially determined by the nature of the weld strength characterized by the tensile strength, metallurgical behavior, surface roughness, weld hardness and micro hardness. In this project an attempt is made to determine and evaluate the influence of the process parameters of FSW on the weldments. The Vickers hardness, tensile strength and radiography are considered for investigation by varying tool speed, tool feed and maintaining onstant depth of penetration of weld. Experiments were conducted on AA6351 Aluminium alloy in a CNC Vertical Machining Centre. Theoutput factors are measured in UTM, Vickers hardness tester and Radiography equipment. Results show strong relation and robust comparison between the weldment strength and process parameters. Hence FSW process variable data base is to be developed for wide variety of metals and alloys for selection of optimum process parameters for efficient weld.

  1. Material modelling for creep-age forming of aluminium alloy 7B04

    Directory of Open Access Journals (Sweden)

    Lam Aaron C.L.

    2015-01-01

    Full Text Available This paper presents a study on the creep-ageing behaviour of a peak-aged aluminium alloy 7B04 under different tensile loads at 115oC and subsequently modelling it for creep-age forming (CAF applications. Mechanical properties and microstructural evolutions of creep-aged specimens were investigated. The material was modelled using a set of unified constitutive equations, which not only captures the material's creep deformation but also takes into account yield strength contributions from solid solution hardening, age hardening and dislocation hardening during creep-ageing. A possible application of the present work is demonstrated by implementing the determined material model into a commercial finite element analysis solver via a user-defined subroutine for springback prediction of creep-age formed plates. A good agreement is observed between the simulated springback values and experimental results. This material model now enables further investigations of 7B04 under various CAF scenarios to be conducted inexpensively via computational modelling.

  2. Effects of heat treatments on the microstructure and mechanical properties of a 6061 aluminium alloy

    Energy Technology Data Exchange (ETDEWEB)

    Maisonnette, D. [Universite de Lyon, CNRS, INSA-Lyon, LaMCoS UMR5259, F-69621 (France); Suery, M. [Universite de Grenoble, SIMaP, UMR CNRS 5266, BP46, Domaine Universitaire, 38402 Saint Martin d' Heres Cedex (France); Nelias, D., E-mail: daniel.nelias@insa-lyon.fr [Universite de Lyon, CNRS, INSA-Lyon, LaMCoS UMR5259, F-69621 (France); Chaudet, P. [Universite de Lyon, CNRS, INSA-Lyon, LaMCoS UMR5259, F-69621 (France); Epicier, T. [Universite de Lyon, CNRS, INSA-Lyon, Mateis UMR5510, F-69621 (France)

    2011-03-15

    Research highlights: {yields} Description of the mechanical behavior of AA6061-T6 at RT after various thermal histories. {yields} A fast-heating device has been designed to reproduce those thermal histories on tensile specimens. {yields} The thermal loadings are representative of the temperature change observed in the HAZ during welding. {yields} The variation of mechanical properties is the result of metallurgical evolution observed by TEM. {yields} The yield stress at RT decreases with the maximum temperature reached during the thermal cycle. - Abstract: This paper describes the mechanical behavior of the 6061-T6 aluminium alloy at room temperature for various previous thermal histories representative of an electron beam welding. A fast-heating device has been designed to control and apply thermal loadings on tensile specimens. Tensile tests show that the yield stress at ambient temperature decreases if the maximum temperature reached increases or if the heating rate decreases. This variation of the mechanical properties is the result of microstructural changes which have been observed by Transmission Electron Microscopy (TEM).

  3. Effect of Negatively Charged Ions on the Formation of Microarc Oxidation Coating on 2024 Aluminium Alloy

    Institute of Scientific and Technical Information of China (English)

    Wei Yang; Bailing Jiang; Aiying Wang; Huiying Shi

    2012-01-01

    The present study deals with the effect of negatively charged ions on the ceramic coating formation on 2024 aluminium alloy during microarc oxidation (MAO) process. On the basis of the experimental results, two steps (the formation of an incipient film without arc presence and the growth of a ceramic coating with arc discharge) of MAO process have been observed. For comparison, four different negatively charged ions studied. It is proved that negatively charged ions strongly participated in the formation of an incipient film with high impedance value at the first step. The growth of ceramic coating depends on the combination between AI of the substrate and O from the electrolyte, and the negatively charged ions are little consumed. As an anodic oxide coating is prepared on the sample surface instead of the incipient film, the first step occurs easily and the growth of ceramic coating is accelerated. Furthermore, the mechanism of negatively charged ions in the formation of the MAO coating has been proposed.

  4. Microstructure and high temperature deformation of an ultra-fine grained ECAP AA7075 aluminium alloy

    Energy Technology Data Exchange (ETDEWEB)

    Malek, Premysl; Turba, Krystof; Cieslar, Miroslav; Harcuba, Petr [Charles Univ., Prague (Czech Republic). Dept. of Physics of Materials

    2013-01-15

    An AA 7075 aluminium alloy with an ultra-fine grained structure was prepared through equal channel angular pressing (ECAP) at pressing temperatures T ECAP of 120, 170, and 220 C. A decrease in T{sub ECAP} from 220 to 120 C was found to lead to a more pronounced refinement of the microstructure and to worse stability of the microstructure - the onset of grain coarsening was displaced to lower temperatures. The material pressed with the highest T{sub ECAP} exhibited superplastic behaviour at temperatures close to 400 C and grain boundary sliding was identified as the dominant operating deformation mechanism. The materials prepared with both of the lower T{sub ECAP} exhibited only enhanced ductility of about 200%, however this behaviour was observed at temperatures as low as 200 C. It was found that this 'low temperature superplasticity' resulted from a combined operation of grain boundary sliding at selected grain boundaries and glide of lattice dislocations. (orig.)

  5. Ductile damage in aluminium alloy thin sheets: Correlation between micro-tomography observations and mechanical modeling

    Energy Technology Data Exchange (ETDEWEB)

    Thuillier, S., E-mail: sandrine.thuillier@univ-ubs.fr [LIMATB, Universite de Bretagne-Sud-rue de Saint Maude BP 92116 56321 Lorient Cedex (France); Maire, E. [MATEIS CNRS UMR 5510, INSA Lyon-7 avenue Jean Capelle 69621 Villeurbanne Cedex (France); Brunet, M. [LaMCoS CNRS UMR 5259, INSA Lyon-7 avenue Jean Capelle 69621 Villeurbanne Cedex (France)

    2012-12-15

    This work deals with the characterization of ductile damage in an aluminium alloy AA6016-T4 by X-ray micro-tomography, as a function of anisotropy and triaxiality. Interrupted tensile tests on notched samples with three different geometries were performed and the void volume fraction was measured for different strain values, up to rupture. It was shown that void volume fraction evolution with the strain is rather similar at 0 Degree-Sign and 90 Degree-Sign to RD but at 45 Degree-Sign to RD it shows a more rapid evolution. Moreover, for the same strain level, a higher void volume fraction was recorded for a higher triaxiality ratio. Whatever the orientation and the stress triaxiality ratio, void volume fraction values range from 5 Multiplication-Sign 10{sup -4} up to 0.04. A numerical model based on Gurson-Tvergaard-Needleman constitutive equations was used to simulate the different tests. Hardening of the material was identified from macroscopic tensile test nucleation material parameters were identified by a direct method from void volume fraction evolution. It can be seen that the influence of triaxiality on void volume fraction is underestimated, though void growth is nicely predicted for the highest triaxiality ratio, for strains below 0.5. The load level was correctly predicted, except for high strain, where coalescence seems necessary to be taken into account.

  6. Thermal Analysis on Butt Welded Aluminium Alloy AA7075 Plate Using FEM

    Directory of Open Access Journals (Sweden)

    M. Pal Pandi

    2014-03-01

    Full Text Available Thermo-mechanical finite element analysis has been performed to assess the residual stress in the butt weld joints of aluminium Alloy AA7075 plates by utilizing the commercial software package ABAQUS. This paper presents an efficient FE technique using equivalent load to precisely predict welding deformations and residual stresses in butt joints. The radial heat flux distribution is considered on the top surface of the weldment. Convective and radiative heat losses are taken into account through boundary conditions for the outward heat flux. Linear FE transient thermal analysis is performed using surface heat source model with Gaussian distribution to compute highest temperature in AA7075 plates. The objective of this project is to simulate the welding process by using the finite element method. After the model is built and verified, the main objective of this project is to study the effects of varying the welding process parameters on the thermo-mechanical responses. In addition to that, the aim of this research is also to find a relationship between welding parameters and the responses of single pass butt welding are evaluated through the finite element analysis. The study of this paper covers the effects of varying heat input, welding speed on the thermo-mechanical responses of the weldment after cooling down to room temperature.

  7. Spectroscopic study of plasma during electrolytic oxidation of magnesium-aluminium alloys

    Science.gov (United States)

    Jovović, J.

    2014-12-01

    Plasma during Electrolytic Oxidation (PEO) of magnesium-aluminium alloys is studied in this work by means of Optical Emission Spectroscopy (OES). Spectral line shapes of the Hβ, Al II 704.21 nm and Mg II 448.11 nm line are analyzed to measure plasma electron number density Ne. From the Hβ line profile, two PEO processes characterized by relatively low electron number densities Ne ≈ 1015 cm-3 and Ne ≈ 2 × 1016 cm-3 were discovered while the shape and shift of Al II and Mg II lines revealed the third process characterized by large electron density Ne = (1-2) × 1017 cm-3. Low Ne processes, related with breakdown in gas bubbles and on oxide surface, are not influenced by anode material or electrolyte composition. The ejection of evaporated anode material through oxide layer is designated here as third PEO process. Using the Boltzmann plot technique, electron temperature of 4000 K and 33000 K is determined from relative intensities of Mg I and O II lines, respectively. Several difficulties in the analysis of spectral line shapes are met during this study and the ways to overcome some of the obstacles are demonstrated.

  8. Natural aging behaviour of friction stir welded 6005A-T6 aluminium alloy

    Energy Technology Data Exchange (ETDEWEB)

    Dong, Peng; Sun, Daqian; Li, Hongmei, E-mail: lihongmei@jlu.edu.cn

    2013-08-01

    By local thermal cycles and hardness measurements, supported by transmission electron microscopy, the post-weld natural aging behaviour of friction stir welded 6005A-T6 aluminium alloy was investigated. The results show that the softening in the nugget zone and thermo-mechanically affected zone immediately after welding is mainly caused by the high peak temperatures and rapid cooling rates, resulting in the original β″ precipitates dissolving and restraining re-precipitation. On the one hand, the hardness recovery in both microstructural zones during post-weld natural aging is attributed to the formation of clusters or GP zones depending on the natural aging time. On the other hand, the softening in the heat-affected zone after welding is due to the transformation of the β′′ to β′ precipitates and the precipitation of Q′. Natural aging has little effect on the microstructure and hardness of the heat-affected zone. The mechanism of natural aging behaviour was discussed.

  9. Inhibition of localized attack on the aluminium alloy AA 6351 in glycol/water solutions

    Energy Technology Data Exchange (ETDEWEB)

    Monticelli, C.; Brunoro, G.; Zucchi, F.; Fagioli, F.

    1989-06-01

    The objective of this work was to examine the feasibility of enhancing pitting resistance of AA 6351 (nominal composition: 1% Si, 0.6% Mg, 0.3% Mn, balance Al) by adding suitable inhibitors to the solutions. The compounds used were two inorganic salts: sodium molybdate and sodium tungstate and two derivatives of pyrimidine: 2-aminopyrimidine (2AP) and 2-hydroxypyrimidine (2HP). The inhibiting efficiencies of these substances were tested by both short-time electrochemical tests (galvanic coupling tests and polarization curves) and long-time immersions under experimental conditions causing the localized attack. Molybdate, tungstate and, to some extent, also 2AP efficiently inhibit AA 6351 localized corrosion in degraded solutions at 80/sup 0/C and in pure boiling solutions, for long exposure periods. The short-time electrochemical tests suggest that molybdate and tungstate are able to retard the electrochemical processes occurring on both the aluminium alloy and the small copper cathodic area produced by copper deposition. On the other hand, the 2AP efficiency is attributed to some complexing capability of this pyrimidine derivative towards dissolved copper ions, that are stabilized in solution. 2HP does not prevent AA 6351 localized attack. (orig./MM).

  10. Influence of aging conditions on the microstructure and tensile strength of aluminium alloy 6063

    Energy Technology Data Exchange (ETDEWEB)

    Gao, R.Q. [Chalmers Univ. of Technology, Goeteborg (Sweden); Sapa Technology, Finspang (Sweden); Stiller, K. [Chalmers Univ. of Technology, Goeteborg (Sweden); Hansen, V. [Hogskolen i Stavanger, Stavanger (Norway); Oskarsson, A. [Sapa Technology, Finspang (Sweden); Danoix, F. [Lab. de Microscopie Iouique, URACNRS Univ. de Rouen, Mount Saint Aignan (France)

    2002-07-01

    The influences of ageing conditions on the strength of a commercial aluminium alloy 6063 (AA 6063) were studied. Materials in three pre-ageing conditions: 288 h natural ageing (i.e. ageing at room temperature (RT)); 3 h natural ageing; and 3 h natural ageing plus 5 h ageing at 80 C, were subsequently aged at 165 C, 185 C and 205 C from 0.25 to 64 hours. Tensile tests were performed after ageing. Microstructural study was performed using transmission electron microscopy (TEM) and atom probe field ion microscopy (APFIM). The results show that for materials with the same pre-ageing condition, the higher the subsequent ageing temperature, the lower the peak strength and the shorter time it takes to reach peak strength. Specimens exposed to longer natural ageing exhibit higher strength during subsequent artificial ageing than those with shorter natural ageing. The contribution of 3-h natural ageing plus 5 h ageing at 80 C to strength is comparable to that of longer natural ageing. Possible causes for such impacts are discussed. (orig.)

  11. Comparison of self-healing ionomer to aluminium-alloy bumpers for protecting spacecraft equipment from space debris impacts

    Science.gov (United States)

    Francesconi, A.; Giacomuzzo, C.; Grande, A. M.; Mudric, T.; Zaccariotto, M.; Etemadi, E.; Di Landro, L.; Galvanetto, U.

    2013-03-01

    This paper discusses the impact behavior of a self-healing ionomeric polymer and compares its protection capability against space debris impacts to that of simple aluminium-alloy bumpers. To this end, 14 impact experiments on both ionomer and Al-7075-T6 thin plates with similar surface density were made with 1.5 mm aluminium spheres at velocity between 1 and 4 km/s.First, the perforation extent in both materials was evaluated vis-à-vis the prediction of well known hole-size equations; then, attention was given to the damage potential of the cloud of fragments ejected from the rear side of the target by analysing the craters pattern and the momentum transferred to witness plates mounted on a ballistic pendulum behind the bumpers.Self-healing was completely successful in all but one ionomer samples and the primary damage on ionomeric polymers was found to be significantly lower than that on aluminium. On the other hand, aluminium plates exhibited slightly better debris fragmentation abilities, even though the protecting performance of ionomers seemed to improve at increasing impact speed.

  12. Soudage homogène MIG de l'alliage d'aluminium 6061 MIG homogeneous welding of 6061 aluminium alloy

    Directory of Open Access Journals (Sweden)

    Benoit Alexandre

    2013-11-01

    Full Text Available Le soudage homogène (métal d'apport identique au métal de base de l'alliage d'aluminium 6061 avec un procédé dit semi-automatique (MIG n'a jamais été reporté jusqu'à maintenant dans la littérature. Nous montrons ici que l'utilisation d'un dérivé du procédé de soudage MIG, le MIG CMT (Cold Metal Transfer permet d'obtenir des cordons de soudures sains (sans fissuration à chaud. De plus des traitements thermiques ont permis de retrouver partiellement ou de restaurer totalement les propriétés de la soudure. Nos résultats sont comparés à des essais de soudage MIG CMT avec le métal d'apport préconisé pour le soudage de l'alliage 6061. The homogeneous welding (same filler metal as base metal of the 6061 aluminium alloy with MIG process has never been reported in the open access literature. This work shows that the CMT (Cold Metal Transfer MIG, a derivative of MIG, allows producing welds without hot-cracking. Moreover, further heat treatments partially increased or fully restore the mechanical properties of the weld. These results are compared with 6061 heterogeneous welds usually met in the industry.

  13. Experimental investigations of visco-plastic properties of the aluminium and tungsten alloys used in KE projectiles

    Directory of Open Access Journals (Sweden)

    Magier M.

    2012-08-01

    Full Text Available The main aim of studies on dynamic behaviour of construction materials at high strain rates is to determine the variation of mechanical properties (strength, plasticity in function of the strain rate and temperature. On the basis of results of dynamic tests on the properties of constructional materials the constitutive models are formulated to create numerical codes applied to solve constructional problems with computer simulation methods. In the case of military applications connected with the phenomena of gunshot and terminal ballistics it’s particularly important to develop a model of strength and armour penetration with KE projectile founded on reliable results of dynamic experiments and constituting the base for further analyses and optimization of projectile designs in order to achieve required penetration depth. Static and dynamic results of strength investigations of the EN AW-7012 aluminium alloy (sabot and tungsten alloy (penetrator are discussed in this paper. Static testing was carried out with the INSTRON testing machine. Dynamic tests have been conducted using the split Hopkinson pressure bars technique at strain rates up to 1,2 ⋅ 104s−1 (for aluminium alloy and 6 ⋅ 103s−1 (for tungsten alloy.

  14. Effect of Mg on microstructures and properties of Al-Mg-Si-Cu aluminium alloys for automotive body sheets

    Institute of Scientific and Technical Information of China (English)

    LIU Hong; SONG Wen-ju; ZHAO Gang; LIU Chun-ming; ZUO Liang

    2005-01-01

    The effects of variation of Mg content on microstructures,the tensile properties and the formability of Al-Mg-Si-Cu alloys for automotive body sheets were investigated by means of scan electron microscopy,optical metallographic analysis,tensile and Ericsson tests.The results show that for Al-Mg-Si-Cu aluminium alloys with excessive Si,with an increment of Mg content,the strength enhances,the specific elongation and Erisson values of alloys decrease,and the number of Mg2 Si constituent increases and that of Al(MnFe)Si type constituents reduces.Al-MgSi-Cu aluminium alloys with excessive Si for automotive body sheets can present obviously the paint bake hardenability during the paint bake cycle (I.e.artificial aging at 170 ℃ for 30 min immediately after the solution treatment and quenching).Suitable Mg content should be controlled in the range of 0.8% and 1.2 % (mass fraction).

  15. Modification of aluminium alloys with rare metals – the basis for advanced materials in construction and transport

    Directory of Open Access Journals (Sweden)

    Skachkov Vladimir Mikchaylovich

    2016-06-01

    Full Text Available The method of process powder injection into aluminum melt shows much promise. Scandium is injected by the high-temperature exchange reaction between the salt melt and aluminum. The best salt compositions were selected. The results of the process are considered to depend on the initial salts. A series of fusions was performed under production conditions at the Kamensk-Uralskii metallurgical plant. It was shown that the injection method for production of aluminoscandium master alloys is technologically feasible. To protect intellectual property of authors, employees of the Institute of Solid State Chemistry, Ural branch of RAS (Russia a patent «Method of alloying of aluminium or alloys on its basis» RU № 2534182 of 27.11.2014 was registered.

  16. Residual stresses in shape memory alloy fiber reinforced aluminium matrix composite

    Science.gov (United States)

    Tsz Loong, Tang; Jamian, Saifulnizan; Ismail, Al Emran; Nur, Nik Hisyammudin Muhd; Watanabe, Yoshimi

    2017-01-01

    Process-induced residual stress in shape memory alloy (SMA) fiber reinforced aluminum (Al) matrix composite was simulated by ANSYS APDL. The manufacturing process of the composite named as NiTi/Al is start with loading and unloading process of nickel titanium (NiTi) wire as SMA to generate a residual plastic strain. Then, this plastic deformed NiTi wire would be embedded into Al to become a composite. Lastly, the composite is heated form 289 K to 363 K and then cooled back to 300 K. Residual stress is generated in composite because of shape memory effect of NiTi and mismatch of thermal coefficient between NiTi wire and Al matrix of composite. ANSYS APDL has been used to simulate the distribution of residual stress and strain in this process. A sensitivity test has been done to determine the optimum number of nodes and elements used. Hence, the number of nodes and elements used are 15680 and 13680, respectively. Furthermore, the distribution of residual stress and strain of nickel fiber reinforced aluminium matrix composite (Ni/Al) and titanium fiber reinforced aluminium matrix composite (Ti/Al) under same simulation process also has been simulated by ANSYS APDL as comparison to NiTi/Al. The simulation results show that compressive residual stress is generated on Al matrix of Ni/Al, Ti/Al and NiTi/Al during heating and cooling process. Besides that, they also have similar trend of residual stress distribution but difference in term of value. For Ni/Al and Ti/Al, they are 0.4% difference on their maximum compressive residual stress at 363K. At same circumstance, NiTi/Al has higher residual stress value which is about 425% higher than Ni/Al and Ti/Al composite. This implies that shape memory effect of NiTi fiber reinforced in composite able to generated higher compressive residual stress in Al matrix, hence able to enhance tensile property of the composite.

  17. Effect of friction time on the properties of friction welded YSZ‐alumina composite and 6061 aluminium alloy

    Directory of Open Access Journals (Sweden)

    Uday M. Basheer

    2012-03-01

    Full Text Available The aim of this work was to study the effect of friction time on the microstructure and mechanical properties of alumina 0, 25, 50 wt% yttria stabilized zirconia (YSZ composite and 6061 aluminium alloy joints formed by friction welding. The alumina-YSZ composites were prepared through slip casting in plaster of Paris molds (POP and subsequently sintered at 1600°C, while the aluminium rods were machined down using a lathe machine to the dimension required. The welding process was carried out under different rotational speeds and friction times, while friction force (0.5 ton-force was kept constant. Scanning electron microscopy was used to characterize the interface of the joints structure. The experimental results showed that the friction time has a significant effect on joint structure and mechanical properties.

  18. Tribological Properties of Aluminium Alloy Composites Reinforced with Multi-Layer Graphene—The Influence of Spark Plasma Texturing Process

    Directory of Open Access Journals (Sweden)

    Marek Kostecki

    2017-08-01

    Full Text Available Self-lubricating composites are designed to obtain materials that reduce energy consumption, improve heat dissipation between moving bodies, and eliminate the need for external lubricants. The use of a solid lubricant in bulk composite material always involves a significant reduction in its mechanical properties, which is usually not an optimal solution. The growing interest in multilayer graphene (MLG, characterised by interesting properties as a component of composites, encouraged the authors to use it as an alternative solid lubricant in aluminium matrix composites instead of graphite. Aluminium alloy 6061 matrix composite reinforced with 2–15 vol % of MLG were synthesised by the spark plasma sintering process (SPS and its modification, spark plasma texturing (SPT, involving deformation of the pre-sintered body in a larger diameter matrix. It was found that the application of the SPT method improves the density and hardness of the composites, resulting in improved tribological properties, particularly in the higher load regime.

  19. The effect of cutting process on surface microstructure and hardness of pure and Al 6061 aluminium alloy

    Directory of Open Access Journals (Sweden)

    Adnan Akkurt

    2015-09-01

    Full Text Available In this study pure aluminium and Al 6061 aluminium alloy material had been cut with saw, milling, submerged plasma, plasma, laser, wire electric discharge machining, oxyfuel and Abrasive water jet. Microstructures and hardness variations of cut surfaces which obtained with different processes have been investigated. Results of the study show that the hardness and surface quality of the cut surface is affected from the kind of cutting process. Microstructure of cut surfaces is affected from the kind of cutting process. Microstructural changes during cutting of the materials are observed with all of the cutting process other than Abrasive water jet. Abrasive water jet method can be effectively used in industrial applications where no microstructural changes and hardness reduction is essential.

  20. Analysis of the tool plunge in friction stir welding - comparison of aluminium alloys 2024 T3 and 2024 T351

    Directory of Open Access Journals (Sweden)

    Veljić Darko

    2016-01-01

    Full Text Available Temperature, plastic strain and heat generation during the plunge stage of the friction stir welding (FSW of high-strength aluminium alloys 2024 T3 and 2024 T351 are considered in this work. The plunging of the tool into the material is done at different rotating speeds. A three-dimensional finite element (FE model for thermomechanical simulation is developed. It is based on arbitrary Lagrangian-Eulerian formulation, and Johnson-Cook material law is used for modelling of material behaviour. From comparison of the numerical results for alloys 2024 T3 and 2024 T351, it can be seen that the former has more intensive heat generation from the plastic deformation, due to its higher strength. Friction heat generation is only slightly different for the two alloys. Therefore, temperatures in the working plate are higher in the alloy 2024 T3 for the same parameters of the plunge stage. Equivalent plastic strain is higher for 2024 T351 alloy, and the highest values are determined under the tool shoulder and around the tool pin. For the alloy 2024 T3, equivalent plastic strain is the highest in the influence zone of the tool pin. [Projekat Ministarstva nauke Republike Srbije, br. TR 34016 i br. TR 35006

  1. Effect of pulsed current and post weld aging treatment on tensile properties of argon arc welded high strength aluminium alloy

    Energy Technology Data Exchange (ETDEWEB)

    Balasubramanian, V. [Department of Manufacturing Engineering, Annamalai University, Annamalai Nagar, Tamil Nadu 608002 (India)], E-mail: visvabalu@yahoo.com; Ravisankar, V. [Department of Manufacturing Engineering, Annamalai University, Annamalai Nagar, Tamil Nadu 608002 (India); Reddy, G. Madhusudhan [Metal Joining Section, Defence Metallurgical Research Laboratory, Kanchanbag (P.O.), Hyderabad 560058 (India)

    2007-06-25

    This paper reveals the effect of pulsed current and post weld aging treatment on tensile properties of argon arc welded AA7075 aluminium alloy. This alloy has gathered wide acceptance in the fabrication of light weight structures requiring high strength-to-weight ratio, such as transportable bridge girders, military vehicles, road tankers and railway transport systems. The preferred welding processes of high strength aluminium alloy are frequently gas tungsten arc welding (GTAW) process and gas metal arc welding (GMAW) process due to their comparatively easier applicability and better economy. Weld fusion zones typically exhibit coarse columnar grains because of the prevailing thermal conditions during weld metal solidification. This often results inferior weld mechanical properties and poor resistance to hot cracking. In this investigation, an attempt has been made to refine the fusion zone grains by applying pulsed current welding technique. Four different welding techniques have been used to fabricate the joints and they are: (i) continuous current GTAW (CCGTAW), (ii) pulsed current GTAW (PCGTAW), (iii) continuous current GMAW (CCGMAW) and (iv) pulsed current GMAW (PCGMAW) processes. As welded joint strength is much lower than the base metal strength and hence, a simple aging treatment has been given to improve the tensile strength of the joints. Current pulsing leads to relatively finer and more equi-axed grain structure in GTA and GMA welds. In contrast, conventional continuous current welding resulted in predominantly columnar grain structures. Post weld aging treatment is accompanied by an increase in tensile strength and tensile ductility.

  2. Effects of Hard Surface Grinding and Activation on Electroless-Nickel Plating on Cast Aluminium Alloy Substrates

    Directory of Open Access Journals (Sweden)

    Olawale Olarewaju Ajibola

    2014-01-01

    Full Text Available This work examined effects of hard surface polishing grits and activation on electroless-nickel (EN plating on cast aluminium alloy substrates in sodium hypophosphite baths. As-received aluminium alloy sample sourced from automobile hydraulic brake master cylinder piston was melted in electric furnace and sand cast into rod. The cast samples were polished using different grits (60 μm–1200 μm before plating. The effects on adhesion, appearance, and quantity of EN deposits on substrates were studied. Observation shows that the quantity of EN deposit is partly dependent on the alloy type and roughness of the surface of the substrates, whereas the adhesion and brightness are not solely controlled by the degree of surface polishing. The best yield in terms of adhesion and appearance was obtained from the activation in zincate and palladium chloride solutions. Higher plating rates (g/mm2/min of 3.01E-05, 2.41E-05, and 2.90E-05 were obtained from chromate, zincate, and chloride than 8.49E-06, 8.86E-06, and 1.69E-05 as obtained from HCl etched, NaOH, and H2O activated surfaces, respectively.

  3. Microstructural evolution of aluminium/Al–Ni–Sm glass forming alloy laminates obtained by Controlled Accumulative Roll Bonding

    Energy Technology Data Exchange (ETDEWEB)

    Anghelus, Adrian, E-mail: anghelus.adrian@yahoo.com; Avettand-Fènoël, Marie-Noëlle, E-mail: marie-noelle.avettand-fenoel@univ-lille1.fr; Cordier, Catherine, E-mail: catherine.cordier@univ-lille1.fr; Taillard, Roland, E-mail: roland.taillard@univ-lille1.fr

    2015-05-15

    Highlights: • Elaboration of a UFG material by controlled ARB of Al/glass forming alloy multilayers. • Effect of the crystalline or amorphous nature of the reinforcement on the formability. • Investigation of the thermo-mechanical stability of the metallic glass. - Abstract: The current work deals with the early steps of the unprecedented elaboration of aluminium/Al based glass forming alloy laminates by only accumulative rolling at room temperature. The Al{sub 1−(x+y)}Ni{sub x}Sm{sub y} metallic glass forming alloy was introduced either in its original amorphous state or after total crystallization. This change of atomic structure, and therefore of both thermal and thermo-mechanical stability and mechanical behaviour, is shown to govern at once the processing parameters, the uniformity of the laminates microstructure and the bond strength at the matrix-reinforcement interfaces. The potential of the process so as to synthesize composite materials with a stable ultrafine structure is finally outlined.

  4. Laser surface alloying (LSA) of aluminium (AA 1200) with TiB2 for hardness improvement

    CSIR Research Space (South Africa)

    Popoola, AP

    2010-10-01

    Full Text Available The present work deals with the development of Aluminium metal matrix composite (MMC) using TiB2 reinforcement. The aim is to improve the microhardness property of the substrate. The surface of the aluminium was sand blasted to improve its laser...

  5. 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.

  6. THREE DIMENSIONAL COMPLEX SHAPES ANALYSIS FROM 3D LOCAL CURVATURE MEASUREMENTS. APPLICATION TO INTERMETALLIC PARTICLES IN ALUMINIUM ALLOY 5XXX

    Directory of Open Access Journals (Sweden)

    Estelle Parra-Denis

    2011-05-01

    Full Text Available The studied material is a 5xxx aluminium alloys containing 2 types of intermetallic particles : Alx(Fe;Mn and Mg2Si. It is usually used in car industry as reinforcement pieces or in packaging industry, such as bottle liquid box lid. Scanning electronic microscope coupled with EDX analysis shows complex shapes of intermetallic particles. The particle shape is obtained during the solidification of alloys. Particles fill vacant spaces between aluminium grains. Therefore final sheet properties depend on intermetallic particles shapes and notably on the matrix-particle interface properties. The goal of the present study is to classify intermetallic particles versus their shapes using local curvature information. The aluminium alloys sample is observed by X ray micro tomography performed at the ESRF. Three dimensional images are segmented, and intermetallic particles are identified in a data base. Each particle is stored as a set of voxels. The surface of each particle is meshed by a marching cubes triangular meshing with the software Amira©. A simplification of the surface is performed by an algorithm contracting the edges. Finally, principal curvatures: kmin and kmax are estimated by Amira© on each facet centre of the mesh. From the full intermetallic population, the bivariate distribution of kmin and kmax is estimated. The obtained graph kmin ¡kmax shows geometrical properties of interface portions of the surface of particles. A factorial correspondence analysis is performed to summarize the information on all intermetallic particles. In the obtained subspace, particles are classified into five shape families, in relation with their interface geometrical properties.

  7. Fracture criteria for automobile crashworthiness simulation of wrought aluminium alloy components

    Energy Technology Data Exchange (ETDEWEB)

    El-Magd, E. [RWTH Aachen (Germany); Gese, H. [MATFEM, Munich (Germany); Tham, R. [Fraunhofer Inst. fuer Kurzzeitdynamik, Freiburg (Germany); Hooputra, H.; Werner, H. [BMW Group, Munich (Germany)

    2001-09-01

    In automobile crashworthiness simulation, the prediction of plastic deformation and fracture of each significant, single component is critical to correctly represent the transient energy absorption through the car structure. There is currently a need, in the commercial FEM community, for validated material fracture models which adequately represent this phenomenon. The aim of this paper is to compare and to validate existing numerical approaches to predict failure with test data. All studies presented in this paper were carried out on aluminium wrought alloys: AlMgSi1.F31 and AlMgSiCu-T6. A viscoplastic material law, whose parameters are derived from uniaxial tensile and compression tests at various strain rates, is developed and presented herein. Fundamental ductile fracture mechanisms such as void nucleation, void growth, and void coalescence as well as shear band fracture are present in the tested samples and taken into consideration in the development of the fracture model. Two approaches to the prediction of fracture initiation are compared. The first is based on failure curves expressed by instantaneous macroscopic stresses and strains (i.e. maximum equivalent plastic strain vs. stress triaxiality). The second approach is based on the modified Gurson model and uses state variables at the mesoscopic scale (i.e. critical void volume fraction). Notched tensile specimens with varying notch radii and axisymmetric shear specimens were used to produce ductile fractures and shear band fractures at different stress states. The critical macroscopic and mesoscopic damage values at the fracture initiation locations were evaluated using FEM simulations of the different specimens. The derived fracture criteria (macroscopic and mesoscopic) were applied to crashworthiness experiments with real components. The quality of the prediction on component level is discussed for both types of criteria. (orig.)

  8. Determination of aluminium in iron, steel and ferrous and non-ferrous alloys by atomic-absorption spectrophotometry after a mercury-cathode separation and extraction of the aluminium-acetylacetone complex.

    Science.gov (United States)

    Donaldson, E M

    1981-07-01

    A method for determining 0.0005% or more of total aluminium in high- and low-alloy steels, iron and ferrovanadium is described. Iron, chromium and other matrix elements are separated from aluminium by electrolysis with a mercury cathode and aluminium is separated from tungsten, titanium, vanadium and phosphate by chloroform extraction of its acetylacetone complex at pH 6.5 from an ammonium acetate-hydrogen peroxide medium. The extract is evaporated to dryness and organic material is destroyed with nitric and perchloric acids. Aluminium is determined by atomic-absorption spectrophotometry in a nitrous oxide-acetylene flame, at 309.3 nm, in a 5% v/v perchloric acid medium containing 1000 mug of sodium per ml. Acid-soluble and acid-insoluble aluminium can also be determined. The method is also applicable to copper- and nickel-base alloys. Results obtained by this method are compared with those obtained spectrophotometrically with Pyrocatechol Violet, after the separations described above followed by the separation of the residual co-extracted iron and copper by a combined ammonium pyrrolidinedithiocarbamate-cupferron-chloroform extraction from 10% v/v hydrochloric acid medium.

  9. Optimization of squeeze casting parameters for non symmetrical AC2A aluminium alloy castings through Taguchi method

    Energy Technology Data Exchange (ETDEWEB)

    Senthil, P. [Coimbatore Institute of Engineering and Technology, Coimbatore (India); Amirthagadeswaran, K. S. [Government College of Technology, Coimbatore (India)

    2012-04-15

    This paper reports a research in which an attempt was made to prepare AC2A aluminium alloy castings of a non symmetrical component through squeeze casting process. The primary objective was to investigate the influence of process parameters on mechanical properties of the castings. Experiments were conducted based on orthogonal array suggested in Taguchi's offline quality control concept. The experimental results showed that squeeze pressure, die preheating temperature and compression holding time were the parameters making significant improvement in mechanical properties. The optimal squeeze casting condition was found and mathematical models were also developed for the process.

  10. Nanocomposite TiC/a-C:H film prepared on titanium aluminium alloy substrates by PSII assistant MW-ECRCVD

    Institute of Scientific and Technical Information of China (English)

    Ma Guo-Jia; Liu Xi-Liang; Zhang Hua-Fang; Wu Hong-Chen; Peng Li-Ping

    2007-01-01

    Thin films of titanium carbide and amorphous hydrogenated carbon have been synthesized on titanium aluminium alloy substrates by PSII assisted MW-ECRCVD with a mirror field. The microstructure, chemical composition and nanometre grains (namely, the so-called nanocomposite structure). The size of TiC grains of nanocomposite TiC/DLC film is about 5 nm. The nanocomposite structure has obvious improvement in the mechanical properties of DLC film.the coherent strength is also obviously enhanced at the critical load of about 35N.

  11. Identification of mechanical properties of weld joints of AlMgSi07.F25 aluminium alloy

    Directory of Open Access Journals (Sweden)

    P. Kopas

    2017-01-01

    Full Text Available The aim of this paper is to present the analysis of selected mechanical properties of weld joints of AlMgSi07.F25 aluminium alloy. We will focus on the influence of the test bar neck shape on the tensile strength characteristics and the course of hardness in the weld joint cross-section. For the welding process using TIG (Tungsten Inert Gas technology we considered AlSi5 as the additive material. This paper also includes a short study of numerical modelling of the test bar welding.

  12. Research of weld joint fatigue life of the AlMgSi07.F25 aluminium alloy under bending-torsion cyclic loading

    Directory of Open Access Journals (Sweden)

    M. Vaško

    2017-01-01

    Full Text Available The contribution deals with a research into the fatigue life of weld joints of AlMgSi07.F25 aluminium alloy. The paper will present unique biaxial testing equipment, process of preparation of specimen rods for fatigue tests, and the results of fatigue life assessment for the aluminium alloy during cyclic bending-torsion loading. Fatigue tests under constant amplitude loading were performed on a special electromechanical machine with a suitable clamping system. The obtained fatigue curves were compared with the most widely-known fatigue criteria such as LIU, F-S and B-M.

  13. Experimental and numerical investigation of the residual yield strength of aluminium alloy EN AW-2024-T3 affected by artificially produced pitting corrosion

    Science.gov (United States)

    Pippig, R.; Schmidl, E.; Steinert, P.; Schubert, A.; Lampke, T.

    2017-03-01

    In this study, the behaviour of the residual yield strength of aluminium alloy EN AW-2024-T3 affected by the morphology and numbers of corrosion pits (defects) is presented. Since specific defect structures are not reproducible during experimental corrosion tests, metal sheets with different numbers of pits and pit shapes are produced using laser micro structuring. The defect structures are measured using laser scanning microscopy. To compare the stress states of the micro structured and real corroded metal sheets, FE-analysis is used. Afterwards, uniaxial tensile tests are carried out and critical defect parameters in terms of yield strength reduction of the investigated aluminium alloy are detected.

  14. Effect of post weld heat treatment on tensile properties and microstructure characteristics of friction stir welded armour grade AA7075-T651 aluminium alloy

    Institute of Scientific and Technical Information of China (English)

    P. SIVARAJ; D. KANAGARAJAN; V. BALASUBRAMANIAN

    2014-01-01

    This paper reports the effects of post weld heat treatments, namely artificial ageing and solution treatment followed by artificial ageing, on microstructure and mechanical properties of 12 mm thick friction stir welded joints of precipitation hardenable high strength armour grade AA7075-T651 aluminium alloy. The tensile properties, such as yield strength, tensile strength, elongation and notch tensile strength, are evaluated and correlated with the microhardness and microstructural features. The scanning electron microscope is used to characterie the fracture surfaces. The solution treatment followed by ageing heat treatment cycle is found to be marginally beneficial in improving the tensile properties of friction stir welds of AA7075-T651 aluminium alloy.

  15. Inhibitive effect of Ce(III) and La(III) cations for AA2219 aluminium alloy corrosion in sodium chloride medium

    Energy Technology Data Exchange (ETDEWEB)

    Venkatasubramanian, G., E-mail: venkatguru_1966@yahoo.co.in [Department of Chemistry, Sathyabama University, Jeppiaar Nagar, Chennai 600119 (India); Sheik Mideen, A. [Department of Chemistry, Sathyabama University, Jeppiaar Nagar, Chennai 600119 (India); Jha, Abhay K. [Materials Processing Division, Vikram Sarabhai Space Centre, Indian Space Research Organisation, Thiruvananthapuram 695022 (India); Kulandainathan, M. Anbu [Electro Organic Chemistry Division, Central Electrochemical Research Institute, Karaikudi 630006 (India)

    2014-11-14

    In this paper, the rare earth chlorides were used to mitigate the dealloying of Al{sub 2}Cu intermetallic particles in aluminium alloy 2219-T87 plate exposed to 0.6 M NaCl solution. The negative shift of cathodic branches of potentiodynamic polarisation curves revealed the cathodic inhibition towards intermetallic dealloying. The low and high frequency time constants obtained from electrochemical impedance spectra revealed an increase in the corrosion resistance due to precipitation of rare earth oxides/hydroxides on the porous surface of native oxide film of aluminium alloy. Scanning electron microscopy coupled with energy dispersive X-ray analysis and atomic force microscopy revealed that intermetallic inclusions are the sites for the formation of cerium and lanthanum deposits which suppress copper redeposition and minimise galvanic interactions between the matrix and Al{sub 2}Cu particles. - Graphical abstract: Scanning electron microscopy and atomic force microscopy reveal the intermetallic inclusions, the sites for the formation of cerium and lanthanum oxide/hydroxide precipitates which prevent intermetallic de-alloying, suppress copper redeposition and minimise galvanic interactions in aluminium alloy 2219-T87 plate. - Highlights: • Ce{sup 3+} and La{sup 3+} act as cathodic inhibitors for AA2219-T87 aluminium alloy in 0.6 M NaCl. • Al{sub 2}Cu intermetallic particles are the sites for the formation of Ce and La precipitates. • The decrease in surface potential by rare earth chlorides confirms their inhibition.

  16. Study of Residual Stress Tensors in High-Speed Milled Specimens of Aluminium Alloys Using a Method of Indent Pairs

    Directory of Open Access Journals (Sweden)

    Felipe Víctor Díaz

    2010-12-01

    Full Text Available From data obtained using a method of indent pairs it was possible to analyse different residual stress states generated in high-speed milled specimens of AA 6082-T6 and AA 7075-T6 aluminium alloys. The present method integrates a special device of indentation into a universal measuring machine, allowing the introduction of elongated indents to significantly reduce the absolute error of measurement. Diverse protocols for operations of high-speed face milling allow us to compare residual stress tensors inherent to climb and conventional cutting zones. Through an exhaustive analysis of the Mohr’s circles corresponding to those zones, a relationship was detected, which expresses the sensitivity of both alloys to develop surface residual stresses.

  17. The 12th China National Foundry Academic Congress held concurrently with China Foundry Week 2011 successfully in Guangzhou

    Institute of Scientific and Technical Information of China (English)

    2011-01-01

    The 12th China National Foundry Academic Congress and China Foundry Week 2011 (hereinafter as Congress),sponsored by the Chinese Mechanical Engineering Society and organized by the Foundry Institution of Chinese Mechanical Engineering Society,was successfully held in Guangzhou from November 14 to 17,2011.Over 530 representatives attended the event.The theme of this event was "Advanced Foundry Technology & Sustainable Development of Foundry Industry".There were 78 academic technical presentations in total,among which 12 were the specially invited speeches that presented in the plenary session.The presentations given in the technical session included 5 on cast steels,15 on non ferrous alloys,7 on cast irons,13 on sand casting process,16 on non sand casting processes,and 10 on moulding materials.A total of 130 technical papers were included in the proceedings of the Congress.

  18. Study of twin-roll cast Aluminium alloys subjected to severe plastic deformation by equal channel angular pressing

    Science.gov (United States)

    Poková, M.; Cieslar, M.

    2014-08-01

    Aluminium alloys prepared by twin-roll casting method become widely used in industry applications. Their high solid solution supersaturation and finer grains ensure better mechanical properties when compared with the direct-chill cast ones. One of the possibilities how to enhance their thermal stability is the addition of zirconium. After heat treatment Al3Zr precipitates form and these pin moving grain boundaries when the material is exposed to higher temperatures. In the present work twin-roll cast aluminium alloys based on AA3003 with and without Zr addition were annealed for 8 hours at 450 °C to enable precipitation of Al3Zr phase. Afterwards they were subjected to severe plastic deformation by equal channel angular pressing, which led to the reduction of average grain size under 1 μm. During subsequent isochronal annealing recovery and recrystallization took place. These processes were monitored by microhardness measurements, light optical microscopy and in-situ transmission electron microscopy. The addition of Zr stabilizes the grain size and increases the recrystallization temperature by 100 °C.

  19. Experimental and numerical investigation on under-water friction stir welding of armour grade AA2519-T87 aluminium alloy

    Directory of Open Access Journals (Sweden)

    S. Sree Sabari

    2016-08-01

    Full Text Available Friction stir welding (FSW is a promising welding process that can join age hardenable aluminium alloys with high joint efficiency. However, the thermal cycles experienced by the material to be joined during FSW resulted in the deterioration of mechanical properties due to the coarsening and dissolution of strengthening precipitates in the thermo-mechanical affected zone (TMAZ and heat affected zone (HAZ. Under water friction stir welding (UWFSW is a variant of FSW process which can maintain low heat input as well as constant heat input along the weld line. The heat conduction and dissipation during UWFSW controls the width of TMAZ and HAZ and also improves the joint properties. In this investigation, an attempt has been made to evaluate the mechanical properties and microstructural characteristics of AA2519-T87 aluminium alloy joints made by FSW and UWFSW processes. Finite element analysis has been used to estimate the temperature distribution and width of TMAZ region in both the joints and the results have been compared with experimental results and subsequently correlated with mechanical properties.

  20. Contribution on Taguchi's Method Application on the Surface Roughness Analysis in End Milling Process on 7136 Aluminium Alloy

    Science.gov (United States)

    ȚÎȚU, M. A.; POP, A. B.

    2016-11-01

    The resulting surface quality after the cutting process is one of the most important characteristics of product quality and also the most frequent customer requirement. Previous research was focused on the effect investigation of machining parameters: cutting speed [1] and feed per tooth [2] on surface roughness. This paper is in itself a continuation of a previous research [3], in which, with Taguchi's method it was determined the level of influence of the cutting parameters on surface roughness of 7136 aluminium alloy in end milling process. The purpose of this paper is to highlight the importance of Taguchi's method use to analyse the surface roughness of 7136 aluminium alloy in end milling process. To conduct the experiments, three cutting parameters were used: cutting speed, feed per tooth and cutting depth. To analyse the surface quality, the surface roughness Ra (the arithmetic average of the absolute values) was measured. It was determined the recommended configuration regarding the optimum values of each machining parameter and the interactions between them, in order to obtain the better cutting process performance and to reduce the surface roughness sensitivity to uncontrollable factors. Based on a full factorial experiment were confirmed the obtained results by applying the Taguchi's method. Final results are a starting point for further research.

  1. Study of surface interactions of ionic liquids with aluminium alloys in corrosion and erosion-corrosion processes

    Energy Technology Data Exchange (ETDEWEB)

    Bermudez, Maria-Dolores [Grupo de Ciencia de Materiales e Ingenieria Metalurgica, Departamento de Ingenieria de Materiales y Fabricacion, Universidad Politecnica de Cartagena, C/ Doctor Fleming s/n, Campus Muralla del Mar, 30202 Cartagena (Spain)]. E-mail: mdolores.bermudez@upct.es; Jimenez, Ana-Eva [Grupo de Ciencia de Materiales e Ingenieria Metalurgica, Departamento de Ingenieria de Materiales y Fabricacion, Universidad Politecnica de Cartagena, C/ Doctor Fleming s/n, Campus Muralla del Mar, 30202 Cartagena (Spain); Martinez-Nicolas, Gines [Grupo de Ciencia de Materiales e Ingenieria Metalurgica, Departamento de Ingenieria de Materiales y Fabricacion, Universidad Politecnica de Cartagena, C/ Doctor Fleming s/n, Campus Muralla del Mar, 30202 Cartagena (Spain)

    2007-06-30

    Surface interactions of alkylimidazolium ionic liquids (ILs) with aluminium alloy Al 2011 have been studied by immersion tests in seven neat ILs [1-n-alkyl-3-methylimidazolium X{sup -} (X = BF{sub 4}; n = 2 (IL1), 6 (IL2), 8 (IL3). X = CF{sub 3}SO{sub 3}; n = 2 (IL4). X = (4-CH{sub 3}C{sub 6}H{sub 4}SO{sub 3}); n = 2 (IL5). X PF{sub 6}; n = 6 (IL6)] and 1-butyl-3-methylpyridinium bis(trifluoromethylsulfonyl)imide (IL7)]. Immersion tests for Al 2011 have also been carried out in 1 wt.% and 5 wt.% solutions of 1-ethyl,3-methylimidazolium tetrafluoroborate (IL1) in water. No corrosion of Al 2011 by neat ILs is observed. The highest corrosion rate for Al 2011 in water is observed in the presence of a 5 wt.% IL1 due to hydrolysis of the anion with hydrogen evolution and formation of aluminium fluoride. Erosion-corrosion processes have been studied for three aluminium alloys (Al 2011, Al 6061 and Al 7075) in a 90 wt.% IL1 solution in water in the presence of {alpha}-alumina particles. The erosion-corrosion rates are around 0.2 mm/year or lower, and increase with increasing copper content to give a corrosion resistance order of Al 6061 > Al 7075 > Al 2011. Results are discussed on the basis of scanning electron microscopy (SEM) observations, energy dispersive spectroscopy (EDS) analysis, X-ray diffraction (XRD) patterns and X-ray photoelectron spectroscopy (XPS) determinations.

  2. Effect of alloying with zinc on SFE of aluminium by study of lattice imperfections in cold worked Al–Zn alloys

    Indian Academy of Sciences (India)

    G Karmakar; R Sen; S K Chattopadhyay; A K Meikap; S K Chatterjee

    2002-08-01

    A detailed X-ray Fourier line shape analysis has been performed on three compositions of Al–Zn alloys viz. Al–3 55 wt% Zn, Al–14 7 wt% Zn and Al–19 3 wt% Zn in fcc phase. It has been found that deformation stacking faults, both intrinsic ' and extrinsic '' are absent in the cold worked state and twin fault is found to be slightly present in the deformed lattice of the two initial compositions of the alloys. Similar to the effect of solute germanium and copper, respectively in Al–Ge and Al–Cu systems, hexagonal zinc also fails to impart faulting in fcc Al–Zn system. This corroborates the fact that aluminium has high stacking fault energy.

  3. Electrochemical Behavior and Microstructure of Recyclable Aluminium-magmesium Alloy Hot-dip Coating Deposited on Low Carbon Steel Substrates

    Institute of Scientific and Technical Information of China (English)

    Panomkorn KWAKHONG; Apichart ARTNASEAW; Chaiyaput KRUEHONG

    2015-01-01

    With the abundance and good corrosion resistance of aluminium, hot-dip technique was used to prepare the recycled Al with 8.2 mass% Mg alloy coating on low carbon steel substrates. Electrochemical behavior of this coating was investigated by an-odic polarization and open circuit potential measurement. Its microstructure and composition were observed by scanning electron microscope and energy-dispersive X-ray spectrometry, respectively. The long lasting corrosion performance of coated steels was in-vestigated under the salt fog spray test. From anodic polarization curves and open circuit potential, recycled Al with 8.2 mass% Mg coating performed adequate sacriifcial ability. At 0.40 V, current density of recycled Al with 8.2 mass% Mg alloy coating was about 200 000 times higher than that of pure recycled Al coating, and was about 0.5 times lower than that of Zn coating. The microstruc-ture of recycled Al with 8.2 mass% Mg alloy coating on the steel substrate consisted of Al3Mg2, Al-Fe intermetallic compound and Al matrix. The results from salt fog spray test showed that recycled Al with 8.2 mass% Mg alloy coated steel had similar corrosion resistance ability to Zn coated steel.

  4. Improvement of the surface properties of aluminium by the formation of intermetallic phases and metal matrix composites during laser surface alloying

    CSIR Research Space (South Africa)

    Mabhali, Luyolo AB

    2011-05-01

    Full Text Available Aluminium is widely used in industry due to its low cost, light weight and excellent workability, but is lacking in wear resistance and hardness. Laser alloying is used to improve the surface properties, such as hardness, by modifying...

  5. The Molecular Foundry (TMF)

    Data.gov (United States)

    Federal Laboratory Consortium — Founded in 2006 by the Department of Energy (DOE), the Molecular Foundry is a critical part of the DOE's National Nanotechnology Initiative, a multi-agency framework...

  6. Foundry energy conservation workbook

    Energy Technology Data Exchange (ETDEWEB)

    1990-01-01

    The foundry industry is a significant user of energy, and therefore, a natural candidate for efforts to save energy and improve efficiency by both governmental agencies and technical/trade associations. These efforts are designed to both improve the national energy position and improve the industry's efficiency and profitability. Increased energy cost and the reduced availability of fossil fuels at certain times have provided the incentive to curb waste and to utilize purchased energy wisely. Energy costs now approach and sometimes exceed 10% of the sales dollar of many foundries. Although energy use by foundries has gradually decreased on a per/ton basis in recent years, the foundry industry must continue to find ways to utilize energy more efficiently. This workbook provides ways to achieve this goal.

  7. Electron irradiation of aluminium-zinc alloys. 2. Radiation-enhanced diffusion in an aluminium-4.5 at% zinc alloy

    Science.gov (United States)

    Zhang, Y. G.; Jones, I. P.

    1989-06-01

    A detailed experimental study of electron radiation-enhanced diffusion in aluminium-4.5 at% zinc is presented. The enhancement factor ( D rad/D thermal) was found to be dependent on dose rate, temperature and electron energy, and varied from ~1 at 170°C to ~10 4 at 25°C. At low temperatures recombination dominates whereas at high temperatures linear annealing is the dominant mechanism for annihilation of point defects. The migration energy of vacancies is thus estimated to be 0.58 ±0.06 eV. The results are compared with a theoretical model. The model requires preferential transport of Zn atoms via the interstitial flux to reproduce the experimental results. The simple model D rad = f vD vC v + f iD iC i + … seems to underestimate D rad.

  8. Gas Quenching during Age Hardening of the Aluminium Casting Alloy AI-7Si-0.3Mg

    Institute of Scientific and Technical Information of China (English)

    A. Rose; O. Kessler; F. Hoffmann; H.W. Zoch

    2004-01-01

    For quenching of age hardenable aluminium alloys today predominantly aqueous quenching media are used.which can lead due to the Leidenfrost phenomenon to a non-uniform cooling of the parts and thus to thermal stresses.Particularly at thin-walled or complex shaped parts local plastic deformations can occur by the uneven thermal stresses. In relation to the conventional quenching procedures in aqueous media, gas quenching exhibits a number of technological.ecological and economical advantages. In comparison to liquid quenching media, gas does not change its phase during quenching. Moreover, the cleaning problem of the parts can be avoided. The quenching intensity can be adjusted by the variable parameters gas pressure and gas speed as well as the kind of gas and thus can be adapted to the requirements of the alloy. By the higher uniformity and the better reproducibility, gas quenching offers a high potential to reduce distortion. The goal of these investigations is to clarify, if the cooling rate during gas quenching is sufficient to obtain the specific required strength after age hardening of the alloy A1-7Si-0.3Mg. For this purpose different tests in high-pressure gas quenching facilities, gas nozzle fields and water quenching baths were performed.

  9. Small Crack Growth and Fatigue Life Predictions for High-Strength Aluminium Alloys. Part 1; Experimental and Fracture Mechanics Analysis

    Science.gov (United States)

    Wu, X. R.; Newman, J. C.; Zhao, W.; Swain, M. H.; Ding, C. F.; Phillips, E. P.

    1998-01-01

    The small crack effect was investigated in two high-strength aluminium alloys: 7075-T6 bare and LC9cs clad alloy. Both experimental and analytical investigations were conducted to study crack initiation and growth of small cracks. In the experimental program, fatigue tests, small crack and large crack tests A,ere conducted under constant amplitude and Mini-TWIST spectrum loading conditions. A pronounced small crack effect was observed in both materials, especially for the negative stress ratios. For all loading conditions, most of the fatigue life of the SENT specimens was shown to be crack propagation from initial material defects or from the cladding layer. In the analysis program, three-dimensional finite element and A weight function methods were used to determine stress intensity factors and to develop SIF equations for surface and corner cracks at the notch in the SENT specimens. A plastisity-induced crack-closure model was used to correlate small and large crack data, and to make fatigue life predictions, Predicted crack-growth rates and fatigue lives agreed well with experiments. A total fatigue life prediction method for the aluminum alloys was developed and demonstrated using the crack-closure model.

  10. Laser surface alloying of aluminium with WC+Co+NiCr for improved wear resistance

    CSIR Research Space (South Africa)

    Nath, S

    2012-03-01

    Full Text Available In the present study, laser surfac ealloying of aluminium with WC + Co + NiCr (in the ratio of 70:15:15) has been conducted using a 5 kW continuous wave (CW) Nd:YAG laser (at a beam diameter of 0.003 m), with the output power ranging from 3 to 3.5 k...

  11. EVALUATION & COMPARISION OF MECHANICAL PROPERTIES OF ALUMINIUM ALLOY 5052 REINFORCED WITH SILICONCARBIDE, GRAPHITE AND FLY ASH HYBRID METAL MATRIX COMPOSITES

    Directory of Open Access Journals (Sweden)

    ANKUSH SACHDEVA

    2013-10-01

    Full Text Available The engineering fraternity has always been looking forward to develop an outstanding and wonder-materials which would fit the ever-changing demands of the world. In order to fullfill the demands various newdiscoveries have been made by scientists, engineers and resrearchers. In todays competitive world many, materials have been tried for various unexplored conditions , but the never ending demand of the world encourages the researchers to develop the new material. Now the researchers are preparing the material by the combination of different materials called hybrid composite material.. Metal Matrix Composites (MMCs have emerged as a class of materials suitable for structural, aerospace, automotive, electronic, thermal and wearapplications owing to their advantages over the conventional materials. The present study was taken up to explore the possibility of using different reinforcements (silicon carbide, fly ash and graphite to enhance the properties of aluminium alloy (Al5052 composites. Different samples were prepared from the aluminium withvarying reinforcement composition. The mechanical properties studied after the experiment were strength, hardness and elongation.Further, these composites were characterized with the help of, mechanical testing and scanning electron microscopy.

  12. Modelling of plastic flow localization and damage development in friction stir welded 6005A aluminium alloy using physics based strain hardening law

    DEFF Research Database (Denmark)

    Nielsen, Kim Lau; Pardoen, Thomas; Tvergaard, Viggo

    2010-01-01

    Plastic flow localisation and ductile failure during tensile testing of friction stir welded aluminium spec- imens are investigated with a specific focus on modelling the local, finite strain, hardening response. In the experimental part, friction stir welds in a 6005A-T6 aluminium alloy were...... prepared and analysed using digital image correlation (DIC) during tensile testing as well as scanning electron microscopy (SEM) on polished samples and on fracture surfaces. The locations of the various regions of the weld were determined based on hardness measurements, while the flow behaviour...

  13. Characterization of AA7050 aluminium alloy processed by ECAP; Caracterizacao da liga de aluminio AA7050 processada por ECAP

    Energy Technology Data Exchange (ETDEWEB)

    Cardoso, K.R.; Guido, V. [Universidade do Vale do Paraiba (UNIVAP), Sao Jose dos Campos, SP (Brazil). Inst. de Pesquisa e Desenvolvimento; Travessa, D.N. [Empresa Brasileira de Aeronautica (EMBRAER), Sao Jose dos Campos, SP (Brazil); Jorge Junior, A.M. [Universidade Federal de Sao Carlos (DEMa/UFSCar), SP (Brazil). Dept. de Engenharia de Materiais

    2010-07-01

    The commercial AA7050 aluminium alloy in the solution heat treated condition (W) was processed by ECAP through route A. Two pressing temperatures (room and 150 deg C and velocities (5 and 30mm/min) were used, as well as different number of passes. The effect of such variables on the microstructure evolution was evaluated using optical and transmission electron microscopy with EDX microanalysis, and xray diffraction. It was found that the microstructure has been refined by ECAP, as a result of subgrains formed within deformation bands. ECAP at 150 deg C resulted in intense precipitation of plate like {eta} phase, which evolves to equiaxial morphology as the number of passes increases. (author)

  14. Multi-Objective Optimization of Friction Stir Welding of Aluminium Alloy Using Grey Relation Analysis with Entropy Measurement Method

    Directory of Open Access Journals (Sweden)

    SAURABH KUMAR GUPTA

    2015-01-01

    Full Text Available The present research focus on optimization of Friction Stir Welding (FSW process parameters for joining of AA6061 aluminium alloy using hybrid approach. The FSW process parameters considered are tool rotational speed, welding speed and axial force. The quality characteristics considered are tensile strength (TS and percentage of tensile elongation (TE. Taguchi based experimental design L9 orthogonal array is used for determining the experimental results. The value of weights corresponding to each quality characteristic is determined by using the entropy measurement method so that their importance can be properly explained. Analysis of Variance (ANOVA is used to determine the contribution of FSW process parameters. The confirmation tests also have been done for verifying the results.

  15. Effect of Process Parameters on Tensile Strength of Friction Stir Welded Cast LM6 Aluminium Alloy Joints

    Institute of Scientific and Technical Information of China (English)

    M. Jayaraman; R.Sivasubramanian; V. Balasubramanian

    2009-01-01

    This paper reports the effect of friction stir welding (FSW) process parameters on tensile strength of cast LM6 aluminium alloy. Joints were made by using different combinations of tool rotation speed, welding speed and axial force each at four levels. The quality of weld zone was investigated using macrostructure and microstructure analysis. Tensile strength of the joints were evaluated and correlated with the weld zone hardness and microstructure. The joint fabricated using a rotational speed of 900 r/min, a welding speed of 75 mm/min and an axial force of 3 kN showed superior tensile strength compared with other joints. The tensile strength and microhardness of the welded joints for the optimum conditions were 166 MPa and 64.8 Hv respectively.

  16. Determination of Optimal Parameters for Diffusion Bonding of Semi-Solid Casting Aluminium Alloy by Response Surface Methodology

    Directory of Open Access Journals (Sweden)

    Kaewploy Somsak

    2015-01-01

    Full Text Available Liquid state welding techniques available are prone to gas porosity problems. To avoid this solid state bonding is usually an alternative of preference. Among solid state bonding techniques, diffusion bonding is often employed in aluminium alloy automotive parts welding in order to enhance their mechanical properties. However, there has been no standard procedure nor has there been any definitive criterion for judicious welding parameters setting. It is thus a matter of importance to find the set of optimal parameters for effective diffusion bonding. This work proposes the use of response surface methodology in determining such a set of optimal parameters. Response surface methodology is more efficient in dealing with complex process compared with other techniques available. There are two variations of response surface methodology. The one adopted in this work is the central composite design approach. This is because when the initial upper and lower bounds of the desired parameters are exceeded the central composite design approach is still capable of yielding the optimal values of the parameters that appear to be out of the initially preset range. Results from the experiments show that the pressing pressure and the holding time affect the tensile strength of jointing. The data obtained from the experiment fits well to a quadratic equation with high coefficient of determination (R2 = 94.21%. It is found that the optimal parameters in the process of jointing semi-solid casting aluminium alloy by using diffusion bonding are the pressing pressure of 2.06 MPa and 214 minutes of the holding time in order to achieve the highest tensile strength of 142.65 MPa

  17. Recovery in aluminium

    DEFF Research Database (Denmark)

    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...... 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 rolling to a thickness...

  18. 铝合金方管开孔柱轴压性能研究%RESEARCH ON BEHAVIOR OF ALUMINIUM ALLOY SHS COLUMNS WITH HOLES UNDER AXIAL COMPRESSION

    Institute of Scientific and Technical Information of China (English)

    冯然; 马义红; 张长锐

    2016-01-01

    采用试验研究和有限元数值分析方法,对6061-T6系列的铝合金方管开孔柱的轴心受压性能进行研究,建立了同时考虑材料非线性和几何非线性的有限元数值模型,对短柱和中长柱的屈曲模式进行模拟,并通过数值模拟结果提出了开孔柱极限承载力的计算方法。利用该有限元模型针对孔洞的存在、大小、数目、位置对铝合金开孔柱的承载力和屈曲模式的影响进行了全面的分析,并通过对比铝合金未开孔轴心受压构件的计算方法与冷弯薄壁型钢开孔轴心受压构件的计算方法,结合数值模拟结果,提出了铝合金开孔轴心受压构件的计算公式。%The experimental study and FE numerical analysis were conducted on 6061-T6 aluminium alloy square hollow section ( SHS) columns with hole under axial compression. Both material and geometrical nonlinearities were considered in the finite element analysis. The accurate finite element models were developed for the buckling analysis of aluminium alloy stub and intermediate columns. Based on the numerical results, the design rules were proposed for the load carrying capacity of aluminium alloy SHS columns with holes. The effects of the existence, size, amount and location of the holes on the load carrying capacity and buckling modes of aluminium alloy SHS columns were evaluated. The design formulas were derived for the aluminium alloy axially compressed members with holes based on the design rules of aluminium alloy structural members and cold-formed steel thin-walled perforated members.

  19. Regarding to the Variance Analysis of Regression Equation of the Surface Roughness obtained by End Milling process of 7136 Aluminium Alloy

    Science.gov (United States)

    POP, A. B.; ȚÎȚU, M. A.

    2016-11-01

    In the metal cutting process, surface quality is intrinsically related to the cutting parameters and to the cutting tool geometry. At the same time, metal cutting processes are closely related to the machining costs. The purpose of this paper is to reduce manufacturing costs and processing time. A study was made, based on the mathematical modelling of the average of the absolute value deviation (Ra) resulting from the end milling process on 7136 aluminium alloy, depending on cutting process parameters. The novel element brought by this paper is the 7136 aluminium alloy type, chosen to conduct the experiments, which is a material developed and patented by Universal Alloy Corporation. This aluminium alloy is used in the aircraft industry to make parts from extruded profiles, and it has not been studied for the proposed research direction. Based on this research, a mathematical model of surface roughness Ra was established according to the cutting parameters studied in a set experimental field. A regression analysis was performed, which identified the quantitative relationships between cutting parameters and the surface roughness. Using the variance analysis ANOVA, the degree of confidence for the achieved results by the regression equation was determined, and the suitability of this equation at every point of the experimental field.

  20. Safety-relevant components made of low-iron, Al-base die-casting alloys; Sicherheitsbauteile aus eisenarmen Aluminium-Druckgusslegierungen

    Energy Technology Data Exchange (ETDEWEB)

    Hielscher, U. [Aluminium Rheinfelden GmbH, Rheinfelden (Germany)

    1999-07-01

    The modern automotive engineering requirements to be met by die-casting aluminium alloys with respect to the microstructure, casting process, compatibility with operating media, and weldability are such that they cannot be met by conventional alloys. Therefore, there was a quest for novel alloys, which at the Aluminium Rheinfelden company has led to the development of two low-iron alloys: Silafont-36 (AlSi9MgMnSr), and Magsimal-59 (AlMg5Si2Mn). The materials properties and some applications are explained. (orig./MM) [German] Von der Automobilindustrie werden an die Aluminiumguss-Legierungen folgende Anforderungen gestellt: 1. sehr duktiles Gefuege, 2. gute Giessbarkeit fuer das Druckgiessverfahren, 3. Vertraeglichkeit mit den Eisenwerkstoffen der Giesswerkzeuge sowie Trenn- und Schmierstoffen, 4. gute Schweissbarkeit und gute Boerdelbarkeit. Die herkoemmlichen Gusslegierungen erfuellen diese Anforderungen nicht; der Aluminium Rheinfelden gelang die Entwicklung von zwei eisenarmen Legierungen: Silafont-36 (AlSi9MgMnSr) und Magsimal-59 (AlMg5Si2Mn). (orig.)

  1. A study of the influence of precipitate-free zones on the strain localization and failure of the aluminium alloy AA7075-T651

    Science.gov (United States)

    Fourmeau, M.; Marioara, C. D.; Børvik, T.; Benallal, A.; Hopperstad, O. S.

    2015-10-01

    Age-hardened aluminium alloys have various degrees of precipitate-free zones (PFZs) along grain boundaries (GBs). The PFZs are weak zones and their existence promotes combined transgranular and intergranular fracture, thus reducing the ductility of the alloy. In this study, transmission electron microscopy (TEM) is used to display the geometrical properties and the chemical composition of the PFZs in the AA7075-T651 aluminium alloy. PFZs are found along grain and sub-GBs and their widths are about 40 and 20 nm, respectively. The PFZs are depleted of alloying elements compared with the nominal composition due to GB precipitation, but still they contain a certain amount of such elements in solid solution which will contribute to increase the yield strength and the work hardening compared to pure aluminium. Based on the results from the TEM study, a micromechanical finite element model of an idealized microstructure including grains and soft zones along the GBs is established. The Gurson model was used to represent the behaviour of the material in the grains and in the soft zones, using different initial void volume fractions to account for GB precipitation. Several loading conditions were applied to the micromechanical model in order to evaluate the localization of strains inside the soft zones and thus to get a better understanding of the role of the PFZs in ductile fracture of age-hardened aluminium alloys. It was found that the global failure strain varies non-monotonically with the global stress triaxiality due to the heterogeneity of the idealized microstructure.

  2. Hydrogen generation by the hydrolysis reaction of ball-milled aluminium-lithium alloys

    Science.gov (United States)

    Chen, Xingyu; Zhao, Zhongwei; Liu, Xuheng; Hao, Mingming; Chen, Ailiang; Tang, Zhongyang

    2014-05-01

    The addition of Li can prevent an inert alumina film from forming on the surface of Al alloy particles, allowing the rapid hydrogen generation of Al alloys to be achieved. However, because the Li content is less than 10%, the hydrogen generation rate and hydrogen yield of Al-Li alloys are significantly decreased. In this work, NaCl is introduced to prepare Al-Li alloys with low Li contents by ball milling. The research results show that by increasing the amount of NaCl added, the ball milling time and Li content can effectively improve the hydrogen generation of the alloys. Under optimal preparation conditions, the ultimate hydrogen yield of Al-Li alloys can reach 100%. The initial water temperature has almost no effect on the generation of hydrogen, even at 0 °C. Ca2+ and Mg2+ can combine with OH- to form the insoluble compounds Ca(OH)2 and Mg(OH)2, which can prevent hydrogen generation. NO3- reacts with Al to form ammonia and reduce the hydrogen yield of the alloys. Therefore, Al-Li alloys should be prevented from reacting with water containing Ca2+, Mg2+ and NO3-. Al-Li alloys must be stored in isolation from air to maintain good hydrogen-generation performances.

  3. Ultrasound Wave Attenuation of Grain Refined High – Zinc Aluminium Sand-cast Alloys

    Directory of Open Access Journals (Sweden)

    Krajewski W.K.

    2015-06-01

    Full Text Available The paper presents results of measuring attenuation coefficient of the Al-20 wt.% Zn alloy (AlZn20 inoculated with different grain refiners. During experiments the melted alloys were doped with Al-Ti3-C0.15 refining master alloy. Basing on measurements performed by Krautkramer USLT2000 device with 1MHz ultrasound wave frequency it was stated that grain refinement reduces the attenuation coefficient by about 20-25%. However, the examined alloys can be still classified as the high-damping ones of attenuation greater than 150 dB/m.

  4. Effect of Mg, Si and Cu content on the microstructure of dilute 6000 series aluminium alloys

    Energy Technology Data Exchange (ETDEWEB)

    Jaafar, Aiza, E-mail: cnaizza@gmail.com [School of Materials and Mineral Resources Engineering, Universiti Sains Malaysia, 14300 Nibong Tebal, Penang (Malaysia); Rahmat, Azmi [School of Materials Engineering, Universiti Malaysia Perlis, Taman Muhibah, 02600 Jejawi, Arau Perlis (Malaysia); Hussain, Zuhailawati [School of Materials and Mineral Resources Engineering, Universiti Sains Malaysia, 14300 Nibong Tebal, Penang (Malaysia); Zainol, Ismail [Chemistry Department, Faculty of Science and Mathematics, Universiti Pendidikan Sultan Idris, 35900 Tanjung Malim, Perak (Malaysia)

    2011-09-01

    Highlights: > The main precipitates formed in the artificially aged dilute alloys are needle-shaped. > The ageing temperature of 100 deg. C is found to be too low to form precipitates. > The number density of precipitates increases with increasing solute contents. > There is a correlation between Mg{sub 2}Si, Si and Cu content and alloys microstructure. > The precipitates kinetics is faster in the less dilute alloys. - Abstract: The effect of Mg, Si and Cu content on the microstructural development during ageing treatment of dilute 6000 series alloys have been investigated using transmission electron microscopy (TEM). Four dilute alloys were used in this study. These alloys were subjected to quenching and artificial ageing at 100 deg. C, 185 deg. C and 300 deg. C. The microstructural developments of the precipitates formed were monitored by TEM. The ageing temperature of 100 deg. C was found to be too low to form precipitates. It was found that needle or rod-shaped precipitates were formed in the alloys after ageing at 185 and 300 deg. C. Prolong ageing up to 1000 h at 300 deg. C resulted in the formation of Mg{sub 2}Si precipitate that coexists with the type of AlFeSi and Si precipitates. The results show a correlation between the Mg{sub 2}Si, Si and Cu content on the microstructure of the four dilute alloys after ageing treatment.

  5. Corrosion properties of plasma electrolytic oxidation coatings on an aluminium alloy – The effect of the PEO process stage

    Energy Technology Data Exchange (ETDEWEB)

    Dehnavi, Vahid, E-mail: vdehnavi@uwo.ca [Department of Chemical and Biochemical Engineering, University of Western Ontario, London, N6A 5B9 ON (Canada); Shoesmith, David W., E-mail: dwshoesm@uwo.ca [Surface Science Western, Department of Chemistry, University of Western Ontario, London, N6A 5B7 ON (Canada); Luan, Ben Li, E-mail: Ben.Luan@nrc-cnrc.gc.ca [National Research Council Canada, 800 Collip Circle, London, N6G4X8 ON (Canada); Department of Chemistry, University of Western Ontario, London, N6A 5B7 ON (Canada); Yari, Mehdi, E-mail: myari@uwo.ca [Department of Chemistry, University of Western Ontario, London, N6A 5B7 ON (Canada); Liu, Xing Yang, E-mail: XingYang.Liu@nrc-cnrc.gc.ca [National Research Council Canada, 800 Collip Circle, London, N6G4X8 ON (Canada); Rohani, Sohrab, E-mail: srohani@uwo.ca [Department of Chemical and Biochemical Engineering, University of Western Ontario, London, N6A 5B9 ON (Canada)

    2015-07-01

    Plasma electrolytic oxidation (PEO) coatings were grown on an aluminium alloy substrate using different processing parameters which enabled samples to be coated to different stages of the PEO process. Electrochemical impedance spectroscopy (EIS) and linear polarization resistance (LPR) techniques were employed to investigate the impedance properties of the resulting oxide coatings which will determine the corrosion performance of the coated alloy. Scanning electron microscopy was used to relate the morphology of the coatings with their corrosion performance. A direct relationship was found between the stage of the PEO process, which affects the microstructure of the coatings, and the corrosion performance. Coating thickness and phase composition did not have any measurable influence on coating corrosion performance. To some degree corrosion performance could be tailored by the processing parameters. - Highlights: • Corrosion performance of PEO coatings was found to be dependent on coating stage. • The PEO stage determined by the process parameters controlled coatings morphology. • Samples coated at the end of stage 3 demonstrated better corrosion properties. • Coating thickness and phase composition showed no influence on corrosion resistance.

  6. MICROSTRUCTURAL CHARACTERISATION AND CORROSION BEHAVIOUR OF TOP SURFACE OF TIG WELDED 2219−T87 ALUMINIUM ALLOY

    Directory of Open Access Journals (Sweden)

    G. Venkatasubramanian

    2013-03-01

    Full Text Available The microstructural characterisation and corrosion behaviour of top surface of tungsten inert gas (TIG welded 2219−T87 aluminium alloy (AA2219–T87 in 0.6 M NaCl solution was studied by optical microscopy, scanning electron microscopy (SEM, potentiodynamic polarisation, and electrochemical impedance spectroscopy (EIS. The optical microscopy and SEM analyses revealed that the welding of base metal (BM with ER2319 filler alloy caused the formation of micro pores and micro cracks on the surface of weld zone (WZ while the welding heat caused the dissolution and segregation of CuAl2 intermetallic particles along the grain boundaries in the heat affected zone (HAZ. The anodic and cathodic branches of polarisation curves showed that the HAZ has lower corrosion resistance than WZ and BM. The decrease of charge transfer resistance of HAZ when comparedto WZ and BM obtained by electrochemical impedance spectroscopy (EIS further confirmed its higher corrosion rate in 0.6 M NaCl solution.

  7. Foundry energy conservation workbook

    Energy Technology Data Exchange (ETDEWEB)

    1990-12-31

    This report discusses methods for promoting energy conservation in foundries. Use of electric power, natural gas, and coke are evaluated. Waste heat recovery systems are considered. Energy consumption in the specific processes of electric melting, natural gas melting, heat treatments, ladle melting, and coke fuel melting is described. An example energy analysis is included. (GHH)

  8. Investigating of the Effect of Rectangular and Trapezium Cross Section of Gating System by CFD Simulation in Cooling of Aluminium Alloy in a Permanent Mould Casting

    Directory of Open Access Journals (Sweden)

    N. A. Chowdhury

    2012-01-01

    Full Text Available This paper presents a systemic study of the effect of different cross section of gate in permanent mould casting of aluminium alloy. To ensure best quality of the product the mould cavity must be filled with clean metal in a controlled manner to ensure smooth, uniform and complete filling. A gating system controls smooth, uniform and complete filling of the cavity by the molten metal. In this paper, CFD models illustrating the effect of rectangular and trapezium cross sections of gating on cooling of Aluminium alloy in a permanent mould casting were investigated. Same hydraulic diameter was assigned for each of the cross section of gating systems. Bottom gating system is used for its low gas entrapment and less surface defect characteristics. By analyzing it has been observed that in rectangular cross section the cooling is more rapid than trapezium cross sections considered in the investigation.

  9. XPS Study of Chemical Changes on the La/Ce Treated Surface of A361 Aluminium Alloy Exposed to Air at Temperatures up to 500∘C

    Directory of Open Access Journals (Sweden)

    A. Pardo

    2009-01-01

    Full Text Available The chemical changes that take place on the rare earth treated surface of the A361 aluminium alloy exposed to air at temperatures between 100 and 500∘C have been examined using X-ray photoelectron spectroscopy (XPS. The most notable features discussed in this work are the disappearance of Mg and Si signals at the tested temperatures and disappearance of the Ce signal at temperatures of 400–500∘C. The biphasic microstructure of the A361 alloy, constituted by close to 12 wt% Si and the Al matrix, plays an important role in many of the results obtained. The notable growth of aluminium oxide across the conversion coating in the case of the Ce-treated surface is related to the structural transformation experienced by the cerium oxide coating at 400–500∘C.

  10. Effect of post weld heat treatment on tensile properties and microstructure characteristics of friction stir welded armour grade AA7075-T651 aluminium alloy

    Directory of Open Access Journals (Sweden)

    P. Sivaraj

    2014-03-01

    Full Text Available This paper reports the effects of post weld heat treatments, namely artificial ageing and solution treatment followed by artificial ageing, on microstructure and mechanical properties of 12 mm thick friction stir welded joints of precipitation hardenable high strength armour grade AA7075-T651 aluminium alloy. The tensile properties, such as yield strength, tensile strength, elongation and notch tensile strength, are evaluated and correlated with the microhardness and microstructural features. The scanning electron microscope is used to characterie the fracture surfaces. The solution treatment followed by ageing heat treatment cycle is found to be marginally beneficial in improving the tensile properties of friction stir welds of AA7075-T651 aluminium alloy.

  11. Impact of M2-Hss Tool Pin Profile in Fsw Welded Joints On Mechanical Properties Of Aa7075-T6 Aluminium Alloy

    Directory of Open Access Journals (Sweden)

    Venugopal S

    2014-05-01

    Full Text Available Friction stir, “welding is a solid state joining process and is widely being considered for aluminium alloys. The main advantage of FSW is the material that is being welded undergoes only localized changes. The welding parameter and tool pin profile play a major role in deciding the weld quality. In this work an effort has been made to analyze microstructure of aluminium AA 7075-T6 alloy. Three different tool profiles (Taper Threaded, cylindrical and square have been used to construct the joints in particular rotational speed. Tensile, Impact, micro hardness of mechanical properties of the joints have been evaluated and the formation of FSP zone has been analyzed microscopically. From the investigation it is found that the threaded cylindrical profile produces highly (defined Strength in welds.

  12. Al-Ti-C中间合金的制备及其在4032铝合金中的应用%Synthesis of Al-Ti-C master alloy and its application in 4032 aluminium alloy

    Institute of Scientific and Technical Information of China (English)

    张静; 赵婧婧; 杜勇

    2014-01-01

    采用元素直接合成法,以工业纯铝、钛屑及石墨颗粒为原料制备Al-Ti-C中间合金,研究和评价了Al-Ti-C中间合金的显微组织及其对4032铝合金铸态组织和活塞模锻件组织的影响。结果表明,制备的Al-Ti-C中间合金由Al基体、长条状Al3 Ti相和细小粒状TiC相,以及少量的游离 C组成。将其应用于4032铝合金中,起到了明显的铸态晶粒细化效果。用该合金制备的活塞模锻件,显微组织和性能优良。%Al-Ti-C master alloy were synthesized by commercial-purity Al billet , Ti powder and graphite particles .The microstructure of the Al-Ti-C master alloy was studied .The grain refinement effects of the master alloy on the as-cast microstructure of 4032 aluminium alloy and the microstructure of mould forging piston fabricated by 4032 aluminium alloy were evaluated .The results show that Al-Ti-C master alloy is composed of Al matrix, long lath Al3Ti phase, fine TiC particles, and small amount of free carbon.With the addition of the master alloy, the as-cast microstructure of 4032 aluminium alloy is observed to be dramatically refined .The modified alloy was used to fabricate mould forging piston.It is found the piston manifests excellent microstructure and properties .

  13. Ab initio and thermodynamic modelling of alloying effects on activity of sacrificial aluminium anodes

    Energy Technology Data Exchange (ETDEWEB)

    Sharma, Anshuman [Materials Science Program, University of Wisconsin-Madison, 1509, University Avenue, Madison, WI 53706 (United States); Zhang Chuan [CompuTherm LLC, 437 S. Yellowstone Dr., Suite 217, Madison, WI 53719 (United States); Chang, Y. Austin [Materials Science Program, University of Wisconsin-Madison, 1509, University Avenue, Madison, WI 53706 (United States); Department of Materials Science and Engineering, University of Wisconsin-Madison, 1509, University Avenue, Madison, WI 53706 (United States); Knoeppel, Ray [A.O. Smith Corporate Technology Centre, 12100, West Park Place, Milwaukee, WI 53224 (United States); Morgan, Dane, E-mail: ddmorgan@wisc.ed [Materials Science Program, University of Wisconsin-Madison, 1509, University Avenue, Madison, WI 53706 (United States); Department of Materials Science and Engineering, University of Wisconsin-Madison, 1509, University Avenue, Madison, WI 53706 (United States)

    2011-05-15

    Research highlights: {yields} Effect of alloying on the corrosion activity of sacrificial Al anodes. {yields} Sn in solid solution form is a key alloying element for activation of Al anodes. {yields} Ternary additions that increase Sn solubility decrease the potential of Al alloys. {yields} Elements bigger than Al expand the Al lattice and allow more Sn to dissolve in Al. {yields} Large ternary dopants can reduce Sn's solubility in Al if they form compounds with Sn. - Abstract: This work summarizes the experimental literature to date on Al-alloy sacrificial anodes and shows that the presence of Sn as an alloying element in solid solution form consistently debases the alloy corrosion potential. This study then assesses the lattice expander theory, which states that lattice-expanding dopants can be used to increase Sn solubility in Al and thereby reduce passivation. The thermodynamic effects on Sn solubility of lattice expanders (Ga, Mg, Zr, In and Bi) are predicted with ab-initio methods. Our results support lattice expander theory although we demonstrate that Sn solubility can decrease by alloying with even large dopants if they form compounds with Sn.

  14. JPL Innovation Foundry

    Science.gov (United States)

    Sherwood, Brent; McCleese, Daniel

    2012-01-01

    Space science missions are increasingly challenged today: in ambition, by increasingly sophisticated hypotheses tested; in development, by the increasing complexity of advanced technologies; in budgeting, by the decline of flagship-class mission opportunities; in management, by expectations for breakthrough science despite a risk-averse programmatic climate; and in planning, by increasing competition for scarce resources. How are the space-science missions of tomorrow being formulated? The paper describes the JPL Innovation Foundry, created in 2011, to respond to this evolving context. The Foundry integrates methods, tools, and experts that span the mission concept lifecycle. Grounded in JPL's heritage of missions, flight instruments, mission proposals, and concept innovation, the Foundry seeks to provide continuity of support and cost-effective, on-call access to the right domain experts at the right time, as science definition teams and Principal Investigators mature mission ideas from "cocktail napkin" to PDR. The Foundry blends JPL capabilities in proposal development and concurrent engineering, including Team X, with new approaches for open-ended concept exploration in earlier, cost-constrained phases, and with ongoing research and technology projects. It applies complexity and cost models, projectformulation lessons learned, and strategy analyses appropriate to each level of concept maturity. The Foundry is organizationally integrated with JPL formulation program offices; staffed by JPL's line organizations for engineering, science, and costing; and overseen by senior Laboratory leaders to assure experienced coordination and review. Incubation of each concept is tailored depending on its maturity and proposal history, and its highest leverage modeling and analysis needs.

  15. JPL Innovation Foundry

    Science.gov (United States)

    Sherwood, Brent; McCleese, Daniel

    2012-01-01

    Space science missions are increasingly challenged today: in ambition, by increasingly sophisticated hypotheses tested; in development, by the increasing complexity of advanced technologies; in budgeting, by the decline of flagship-class mission opportunities; in management, by expectations for breakthrough science despite a risk-averse programmatic climate; and in planning, by increasing competition for scarce resources. How are the space-science missions of tomorrow being formulated? The paper describes the JPL Innovation Foundry, created in 2011, to respond to this evolving context. The Foundry integrates methods, tools, and experts that span the mission concept lifecycle. Grounded in JPL's heritage of missions, flight instruments, mission proposals, and concept innovation, the Foundry seeks to provide continuity of support and cost-effective, on-call access to the right domain experts at the right time, as science definition teams and Principal Investigators mature mission ideas from "cocktail napkin" to PDR. The Foundry blends JPL capabilities in proposal development and concurrent engineering, including Team X, with new approaches for open-ended concept exploration in earlier, cost-constrained phases, and with ongoing research and technology projects. It applies complexity and cost models, projectformulation lessons learned, and strategy analyses appropriate to each level of concept maturity. The Foundry is organizationally integrated with JPL formulation program offices; staffed by JPL's line organizations for engineering, science, and costing; and overseen by senior Laboratory leaders to assure experienced coordination and review. Incubation of each concept is tailored depending on its maturity and proposal history, and its highest leverage modeling and analysis needs.

  16. JPL Innovation Foundry

    Science.gov (United States)

    Sherwood, Brent; McCleese, Daniel

    2013-08-01

    Space science missions are increasingly challenged today: in ambition, by increasingly sophisticated hypotheses tested; in development, by the increasing complexity of advanced technologies; in budgeting, by the decline of flagship-class mission opportunities; in management, by expectations for breakthrough science despite a risk-averse programmatic climate; and in planning, by increasing competition for scarce resources. How are the space-science missions of tomorrow being formulated? The paper describes the JPL Innovation Foundry, created in 2011, to respond to this evolving context. The Foundry integrates methods, tools, and experts that span the mission concept lifecycle. Grounded in JPL's heritage of missions, flight instruments, mission proposals, and concept innovation, the Foundry seeks to provide continuity of support and cost-effective, on-call access to the right domain experts at the right time, as science definition teams and Principal Investigators mature mission ideas from "cocktail napkin" to PDR. The Foundry blends JPL capabilities in proposal development and concurrent engineering, including Team X, with new approaches for open-ended concept exploration in earlier, cost-constrained phases, and with ongoing research and technology projects. It applies complexity and cost models, project-formulation lessons learned, and strategy analyses appropriate to each level of concept maturity. The Foundry is organizationally integrated with JPL formulation program offices; staffed by JPL's line organizations for engineering, science, and costing; and overseen by senior Laboratory leaders to assure experienced coordination and review. Incubation of each concept is tailored depending on its maturity and proposal history, and its highest-leverage modeling and analysis needs.

  17. Comparative Investigation on Modal analysis of LM25 Aluminium alloy with other Aluminim alloys using Finite element analysis software

    Science.gov (United States)

    Arunkumar, S.; Baskaralal, V. P. M.; Muthuraman, V.

    2017-03-01

    The rudimentary steps of the modal analysis and simulation are carried out. The modal analysis is carried out on the different Aluminum Alloys cantilever beam. The cantilever beam is designed in the graphical environment of the ANSYS. The cantilever beam was fine-tuned on one end with all degree of liberation on this end were taken, beam cannot move and rotate. Mode shapes and natural frequencies are premeditated in platforms ANSYS with arithmetical formulation of the direct solver including the block Lanczos method. Aluminum alloys are widely utilized in much application due to their estimable weight to vigor property. Many examination works have been distributed out to make developments the mechanical properties of aluminum alloys. The composition of alloying elements plays a consequential role in deciding the properties of an alloy. In this study a numerical analysis implement i.e., finite element analysis (FEA) is utilized. The work obtainable in this paper is aimed at the study of effect of modal analysis of different aluminum alloys. The modeling and analysis is carried out utilizing ANSYS FEA software. A modal analysis is carried out to understand the modes of frequency demeanor of the material considered. The modal analysis play a vital role in the design of components subjected to high vibration.

  18. Fatigue behavior of GMAW welded Aluminium alloy AA7020; Comportamiento a fatiga de uniones soldadas GMAW de la aleacion de aluminio AA 7020

    Energy Technology Data Exchange (ETDEWEB)

    Bloem, C. A.; Salvador, M. D.; Amigo, V.; Vicente, A.

    2007-07-01

    The aim of this investigation is to evaluate the influence on the fatigue behavior by the finishing of the bulge in a welded aluminium-zinc-magnesium alloy AA7020. It was determined that total or partial elimination of the bulge has very little influence on its behavior, giving a very similar result on both cases, where one is better than the other by only 3%. (Author) 20 refs.

  19. Influence of Various Process Parameters on the Density of Sintered Aluminium Alloys

    Directory of Open Access Journals (Sweden)

    Mateusz Laska

    2012-01-01

    Full Text Available This paper presents the results of density measurements carried out on Alumix sintered parts. ECKA Alumix aluminium powders were used because of their wide application in the powder metallurgy industry. The compacts were produced using a wide range of compaction pressures for three different chemical compositions. The compacts were then sintered under a pure dry nitrogen atmosphere at three different temperatures. The heating and cooling rates were the same throughout the entire test. The results showed that the green density increases with compaction pressure, but that sintered density is independent of green density (compaction pressure for each sintering temperature.

  20. Waste foundry sand: Environmental implication and characterization

    Directory of Open Access Journals (Sweden)

    Gabriela Penkaitis

    2012-12-01

    Full Text Available This paper presents the results of analyses using Scanning Electron Microscopy in field samples of waste foundry sand, as well as the results of granulometric, chemical and groundwater analyses. Field data allowed to characterize waste foundry sand and showed that there are elevated concentrations of metals in the groundwater (iron, manganese, boron and selenium, in addition to other potentially toxic elements (chromium, copper, cobalt, nickel, zinc, aluminum, iron, manganese, which are present in the waste and are considered not hazardous by current standards. Even if these elements are not considered hazardous, their concentrations above the permissible limit compromise the environmental quality of the site, posing risks to the local population, since they work in agriculture and use groundwater. Two different types of waste foundry sands were identified using granulometric analyses. Electron microscopy showed features related to morphological, chemical and mineralogical characteristics of grains that make up the waste. Quartz was the dominant mineral. Waste foundry sand is composed of two types of grains: a rounded grain with almost no incrustations formed during alloy production, and a second type of grain, which is not rounded, has incrustations, and always has several metals derived from alloys and associated with these incrustations. Chemical elements detected in groundwater with concentrations above the limits established by the regulatory bodies were found in wells located in the landfill area. Most of these elements show higher concentrations downstream, some of them with concentrations above the regulatory limit, and others show an increase in concentration upstream, indicating that the landfill may be impacting the local environment.

  1. Ballistic behavior of boron carbide reinforced AA7075 aluminium alloy using friction stir processing–An experimental study and analytical approach

    Institute of Scientific and Technical Information of China (English)

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

    2016-01-01

    High strength-to-weight ratio of non-ferrous alloys, such as aluminium, magnesium and titanium alloys, are considered to be possible replacement of widely accepted steels in transportation and automobile sectors. Among these alloys, magnesium is self explosive and titanium is costlier, and aluminium is most likely to replace steels. Application of aluminium or its alloys is also thought of as an appropriate replacement in defence field, especially to enhance the easiness in mobility of combat vehicles while maintaining the same standard as that of conventional armour grade steels. Hence most of the investigations have been confined to aluminium or its alloys as base material and open an era of developing the newer composite materials to address the major limitation, i.e. tribological properties. The surface composites can be fabricated by incorporating the ceramic carbides like silicon carbide, carbides of transition metals and oxides of aluminium using surface modification techniques, such as high energy laser melt treatment, high energy electron beam irradiation and thermal spray process which are based on fusion route. These techniques yield the fusion related problems, such as interfacial reaction, pin holes, shrinkage cavities or voids and other casting related defects, and pave the way to need of an efficient technique which must be based on solid state. Recently developed friction stir processing technique was used in the present investigation for surface modification of AA7075 aluminum alloy, which is an alternative to steels. In the present investigation, 160μm sized boron carbide powder was procured and was reduced to 60μm and 30μm using high energy ball mill. Subsequently these powders were used to fabricate the surface composites using friction stir processing. Ballistic performance testing as per the military standard (JIS.0108.01) was carried out. In the present work, an analytical method of predicting the ballistic behavior of surface composites

  2. Computer simulations of martensitic transformations in iron-nickel and nickel-aluminium alloys

    CERN Document Server

    Meyer, R J

    1998-01-01

    This thesis focuses on the martensitic transformations in iron-nickel and nickel-aluminum alloys. Molecular-dynamics simulations have been done, employing potentials based on the so-called embedded-atom method (EAM). These potentials were obtained by a fit of parameterized functions to experimental data of the elements iron, nickel, and aluminum as well as the intermetallic compound NiAl. Many aspects of the austenitic transformation in iron-nickel alloys and both, the martensitic and austenitic transformations, in nickel-aluminum alloys were reproduced well by the simulations. The results allow to draw conclusions on the reasons of differences and similarities in the behavior of both alloy systems.

  3. Effect of post annealing temperatures on microstructures and mechanical properties of cryorolled 5052 aluminium sheet alloy

    Science.gov (United States)

    Anas, N. M.; Umar, Z. A. A.; Zuhailawati, H.; Anasyida, A. S.

    2017-07-01

    The effect of post annealing temperature of cryorolled 5052 Al alloy after cryorolling process at 30% thickness reduction was investigated, focusing on the evolution of microstructures and mechanical properties. The evolution of microstructure was investigated using optical microscopy (OM). The mechanical behaviour of the samples have been evaluated through Vickers hardness and tensile test performed at room temperature. The results showed that the post annealing on cryorolled 5052 Al alloy have enhanced the ductility with sacrificing the hardness and strength. The lattice strain of post annealed 5052 Al alloy decreased with increasing of annealing temperatures. The evolution of microstructure of the post annealed 5052 Al alloy showed equiaxed grains at 200°C and grain coarsening as post annealing temperature increases to 350°C. The result of crystallite size confirmed the grain size increased as the post annealing temperature rises.

  4. Interfacial heat-transfer between A356-aluminium alloy and metal mould

    Institute of Scientific and Technical Information of China (English)

    Zhao Jianhua; Tian Jun; Qian Hancheng

    2009-01-01

    The interracial heat-transfer coefficient at casting/mould interface is a key factor that impacts the simulation accuracy of solidification progress. At present, the simulation result of using available data is comparatively different from the practice. In the current study, the methods of radial heating and electricity measurement under steady-state condition were employed to study the nature of interfacial heat-transfer between A356 Aluminum alloy and metal mould. The experimental results show that the interracial heat-transfer between A356 Aluminum alloy and the outer mould drops linearly with time while that of A356 aluminum alloy and the inner mould increases with time during cooling. The interracial heat-transfer coefficient between A356 aluminum alloy and mould is inversely proportional to the electrical resistance.

  5. Evaluation of pitting corrosion with electrochemical impedance spectroscopy (EIS) for alumina/aluminium alloys composites

    Energy Technology Data Exchange (ETDEWEB)

    Odegard, C.; Bronson, A. [Univ. of Texas, El Paso, TX (United States)

    1998-12-31

    The pitting susceptibility of monolithic aluminum 6061 alloy and alumina/aluminum alloy composites has been analyzed by using electrochemical impedance spectroscopy and subsequent comparison with their polarization scans. The composites consisting of 0.10 and 0.15 volume fraction of alumina particles (VFAP) and the monolith as cylindrical electrodes were rotated at 1500 rpm while immersed in NaCl solution. The passive currents of the composites were greater than that of the monolith as per the polarization scans. The impedance spectra were acquired at constant potential increments along the passive region up to the pitting potential. The impedance spectra represented by semicircles on a Nyquist plot acquired above the pitting potential collapsed underneath the spectra obtained in the passive region near the corrosion potential for the monolithic alloy and composites. The impedance spectra modeled with a simplified equivalent circuit indicate that the effective capacitance for the composites is greater than that of the monolithic alloy.

  6. Evolution of microstructure and mechanical properties of A356 aluminium alloy processed by hot spinning process

    Directory of Open Access Journals (Sweden)

    Xiao-yan Wu

    2017-03-01

    Full Text Available The evolution of microstructure and mechanical properties of A356 aluminum alloy subjected to hot spinning process has been investigated. The results indicated that the deformation process homogenized microstructure and improved mechanical properties of the A356 aluminum alloy. During the hot spinning process, eutectic Si particles and Fe-rich phases were fragmented, and porosities were eliminated. In addition, recrystallization of Al matrix and precipitation of AlSiTi phases occurred. The mechanical property testing results indicated that there was a significant increase of ductility and a decrease of average microhardness in deformed alloy over die-cast alloy. This is attributed to uniform distribution of finer spherical eutectic Si particles, the elimination of casting defects and to the recrystallized finer grain structure.

  7. The Effect of Chemical Composition and Structure on the Corrosion Resistance of Plated Aluminium Alloy Strips

    Science.gov (United States)

    Klyszewski, Andrzej; Zelechowski, Janusz; Opyrchal, Mieczyslaw; Nowak, Marek; Frontczak, Andrzej; Rutecki, Pawel

    Thin 3003 alloy strips plated with 4343 alloy were subjected to microstructure examinations, X-ray phase analysis, corrosion testing, and measurement of basic mechanical properties. In a similar manner, the properties of heat exchangers made from the plated strip were characterised, watching the long-term consequences of their use in vehicles. The results of investigations were applied in the manufacturing technology of thin plated strips for heat exchangers used by the automotive industry.

  8. The New Heat Treatment Technology of A356 Aluminium Alloy Prepared by Ptc

    Science.gov (United States)

    Zhang, Lianyong; Jiang, Yanhua; Ma, Zhuang; Wang, Wenkui

    Phase Transition Cooling (PTC), using the absorbed latent heat during the melting of phase transition cooling medium to cool and solidify alloys in the process of casting, is a new casting technology. Specimens of A356 casting aluminum alloy were prepared by this method in the paper. The new heat treatment process (cast and then aging directly without solid solution) of A356 alloy was performed. For comparison, the conventional T6 heat treatment (solution and then aging treatment) was performed too. The mechanical properties of A356 alloy with different heat treatments were measured by tensile strength testing methods and microstructures of the alloy with different heat treatment process were investigated by optical microscopy (OM), scanning electron microscopy (SEM), differential scanning calorimetry (DSC), X-rays diffraction (XRD) and transmission electron microscopy (TEM) too. The results show that ultimate tensile strength (UTS) of A356 alloy with the new heat treatment process is much higher than that with conventional heat treatment while the elongations with the two heat treatment processes are very close. This is due to the grain refinement obtained after PTC processing.

  9. APPLICATION OF CHEMICAL PRE-TREATMENT ON THE POLISHED SURFACE OF ALUMINIUM ALLOYS

    Directory of Open Access Journals (Sweden)

    Pavel Kraus

    2016-12-01

    Full Text Available This paper reports the preparation and characterization of thin transparent nanolayers with phase composition ZrF4 and different modification of SiO2 with special focus on affecting the surface roughness of the material and the way of exclusion of the thin nanolayer on the surface of the polished aluminium material. The thin nanolayer was prepared by the sol-gel method. The final treatment based on PTFE was applied on the surface of some samples. This treatment is suitable for increasing wear resistance. The films were characterized with help of SEM microscopy and EDS analysis. The surface roughness was measured with classical surface roughness tester. The results on this theme have already published but not on the polished surface of the aluminium material. The results from the experiment show the problems with application of these nanolayers because a cracks were found on the surface of the material and deformations of the layer after application of the PTFE final layer. The surface layer formation is discussed.

  10. Recent developments of the aluminium-lithium system alloys for aircraft uses; Recentes desenvolvimentos das ligas do sistema aluminio-litio para fins aeronauticos

    Energy Technology Data Exchange (ETDEWEB)

    Goncalves, Marcelo; Plaut, Ronald Lesley

    1992-12-31

    A brief review is made of the latest developments in the production of Aluminium-Lithium alloys. The necessity for new materials in the field of aeronautics has speeded up research on metallic and non-metallic materials. Lately, a good part of the research in the field of metallic components has been directed at Al-Li alloys. More recently, with the development of quaternary alloys Al-Li-X-X, the old problem of low toughness was overcome. The finality of this study is to cover the developments of the mentioned alloys, including the fundamentals of physical metallurgy of the complex system recently developed Al-Li-Cu-Mg. (author) 27 refs., 2 figs., 4 tabs.

  11. Synergism between cerium nitrate and sodium dodecylbenzenesulfonate on corrosion of AA5052 aluminium alloy in 3 wt.% NaCl solution

    Science.gov (United States)

    Liu, Jie; Wang, Dapeng; Gao, Lixin; Zhang, Daquan

    2016-12-01

    The synergistic inhibition effect of rare earth cerium nitrate and sodium dodecylbenzenesulfonate (DBS) on corrosion of AA5052 aluminium alloy in 3 wt.% NaCl solution was investigated by electrochemical impedance spectroscopy (EIS), potentiodynamic polarization curve, scanning electron microscope (SEM) and Fourier transform infrared spectroscopy (FT-IR). The results show that the single cerium nitrate or DBS has a limited inhibition effect against corrosion of AA5052 alloy. The combination cerium ions with DBS produced strong synergistic effect on corrosion inhibition for AA5052 alloy and rendered a negaitve shift of the corrosion potential. The formation of the complex of Al(DBS)3 and Ce(DBS)3 stabilized the passive film of Al2O3 and CeO2, retarding both the cathodic and anodic processes of AA5052 alloy corrosion reaction significantly.

  12. Effect of thermal exposure on mechanical properties hypo eutectic aerospace grade aluminium-silicon alloy

    Science.gov (United States)

    Nagesh Kumar, R.; Ram Prabhu, T.; Siddaraju, C.

    2016-09-01

    The effect of thermal exposure on the mechanical properties of a C355.0 aerospace grade aluminum-silicon alloy (5% Si - 1.2% Cu - 0.5% Mg) was investigated in the present study. The alloy specimens were subjected to T6 (solution treatment and artificial ageing treatment) temper treatment to enhance the strength properties through precipitation hardening. The T6 temper treatment involved solution heat treatment at 520oC for 6h, followed by water quenching and ageing at 150oC. After the heat treatment, the specimens were exposed to various temperatures (50oC, 100oC, 150oC, 200oC and 250oC) for 5 and 10 h to study the structural applications of this alloy to the various Mach number military aircrafts. After the thermal exposure, specimens were tested for tensile, hardness and impact properties (Charpy). The microstructure of the thermal exposed specimens was examined in the optical microscopes and correlated with the mechanical properties results. In summary, an increase of exposure time has a different effect on the tensile and hardness properties of the alloy. For the exposure time 5h, the tensile and hardness properties increase upto 100oC and later decrease with an increase of temperature. In contrast, the tensile and hardness properties linearly decrease with an increase of temperature. Several factors such as matrix grain growth, diffusion rate, Si particles size and distribution, precipitate stability play a key role on deciding the tensile properties of the alloy. Comparing the relative effects of temperature and time, the temperature effects dominate more in deteriorating tensile properties of the alloy. There are no effects of exposure temperature and/or time on the impact properties of the alloy.

  13. NUMERICAL SIMULATION OF INDUCTION SKULL MELTING PROCESS FOR TITANIUM-ALUMINIUM BASE ALLOY

    Institute of Scientific and Technical Information of China (English)

    Z.Y. Chen; L.J. Xu; F.T. Kong; Q. Shu; Y.Y. Chen

    2004-01-01

    The mathematics model for temperature field of water-cooling copper crucible induction skull melting process was established. The program for simulating temperature field of melting process was developed with finite element method. The temperature field of the melting process for Ti-47Al-2Cr-2Nb alloy was calculated. During melting period, the temperature is raised gradually along radius augmentation direction. The elements of the charge near the crucible wall are molten first. The center elements of the charge are molten last. The melting time of the center element is just that of all the charge melting. The melting time of Ti-47Al-2Cr-2Nb alloy is 15min. In which, the charge was heated by low power 80kW for 9min and by high power 300kW for 6min. When melting Ti-47Al-2Cr-2Nb alloy,the loading power is nearly direct proportion to melt temperature. Increasing loading power may raise melt temperature. The best melting power of Ti-47Al-2Cr-2Nb alloy is 305-310kW. This is identical with the melting test and has guidance sense to the melting process of actual titanium alloy.

  14. Comparison of modification with strontium and the refining with antimony in A 356 aluminium alloys; Comparacao entre a modificacao com estroncio e o refino com antimonio em ligas de aluminio a 356

    Energy Technology Data Exchange (ETDEWEB)

    Fuoco, Ricardo; Correa, Edison Roberto; Correa, Alzira V.O.; Bocalini Junior, Mario

    1992-12-31

    Strontium and Antimony treated A356 aluminium alloy samples were metallographically characterized in the as cast and solution and aged conditions. Antimony treated alloy has shown slower spheroidizing kinetics of the Silicon particles during solution treatment, lower porosity level and higher tensile strength and elongation than Strontium treated one. (author) 26 refs., 13 figs., 2 tabs.

  15. Structure and properties of sintered titanium alloyed with aluminium, molybdenum and oxygen

    Energy Technology Data Exchange (ETDEWEB)

    Anokhin, V.M.; Petrunko, A.N. [State Research and Design Titanium Institute, Zaporozhye (Ukraine); Ivasishin, O.M. [Institute for Metal Physics, National Academy of Sciences of Ukraine, 36 Vernadsky St, 142 Kiev (Ukraine)

    1998-03-15

    Titanium alloys of Ti-Al-Mo-O system were manufactured by blended elemental powder method using Ti, Al, Mo and TiO{sub 2} powders as starting materials. It was found that cold compaction pressure of 800 MPa followed by sintering at 1150-1200 C, for 4 h provided sufficient densification of titanium materials. Complete dissolution of alloying elements in the titanium matrix resulted in a good combination of mechanical properties. Examples of alloys chosen for possible application were Ti-(1.5-2.0)%Mo-0.7%TiO{sub 2} and Ti-2%Al-2%Mo. The latter has already been tried for manufacturing parts in automotive industry. (orig.) 3 refs.

  16. Fracture performance of high strength steels, aluminium and magnesium alloys during plastic deformation

    Directory of Open Access Journals (Sweden)

    Yu Haiyan

    2015-01-01

    Full Text Available A series of uniaxial tension tests were performed for 5052 and 6061 aluminum alloys, AZ31B magnesium alloy, TRIP600 and DP600 steels, to obtain a better understanding of their fracture performance. Scanning electron microscope (SEM observation of the microstructure evolution was conducted. The dimple structure, orientation relationship between the fracture surface and tensile direction, necking behavior were analyzed. The fracture mechanism and fracture mode of each material was discussed in detail. The results show that TRIP600 steel is subject to a typical inter-granular ductile fracture combined by shear fracture. DP600 steel belongs to mainly ductility mixed with normal fracture. Both 5052 and 6061 aluminum alloys are subject to a mixed ductility fracture and brittle fracture. AA5052 and AA6061 belong to a typical shear fracture and a normal fracture, respectively. Magnesium AZ31B is typical of a brittle fracture combined with normal fracture.

  17. Study of Pitting Corrosion Behavior of FSW weldments of AA6101- T6 Aluminium Alloy

    Directory of Open Access Journals (Sweden)

    L.V. Kamble

    2015-09-01

    Full Text Available Friction Stir Welding (FSW is a promising solid state joining process widely used generally for Al alloys, especially in aerospace, marine and automobile applications. In present work, the microstructure and corrosion behavior of friction stir welded AA6101 T6 Al alloy is studied. The friction stir welding was carried using vertical milling machine with different tool rotational speeds and welding speeds. The microstructure at weld nugget or stir zone (SN, thermo-mechanically affected zone (TMAZ, heat affected zone (HAZ and base metal were observed using optical microscopy. The corrosion tests of base alloy and welded joints were carried out in 3.5% NaCl solution at temperature of 30º C. Corrosion rate and emf were determined using cyclic polarization measurement.

  18. Computation material science of structural-phase transformation in casting aluminium alloys

    Science.gov (United States)

    Golod, V. M.; Dobosh, L. Yu

    2017-04-01

    Successive stages of computer simulation the formation of the casting microstructure under non-equilibrium conditions of crystallization of multicomponent aluminum alloys are presented. On the basis of computer thermodynamics and heat transfer during solidification of macroscale shaped castings are specified the boundary conditions of local heat exchange at mesoscale modeling of non-equilibrium formation the solid phase and of the component redistribution between phases during coalescence of secondary dendrite branches. Computer analysis of structural - phase transitions based on the principle of additive physico-chemical effect of the alloy components in the process of diffusional - capillary morphological evolution of the dendrite structure and the o of local dendrite heterogeneity which stochastic nature and extent are revealed under metallographic study and modeling by the Monte Carlo method. The integrated computational materials science tools at researches of alloys are focused and implemented on analysis the multiple-factor system of casting processes and prediction of casting microstructure.

  19. Determination of Aluminium in lead-calcium-aluminium ternary alloy by chrome azurol Sphotometry%铬天青S光度法测定铅钙铝三元合金中铝

    Institute of Scientific and Technical Information of China (English)

    丁林立

    2001-01-01

    In the medium of hexamethylenetetramine buffer solution(pH 5-6) aluminium reacts with chrome azurol S to produce a water dissoluble purple complex.The absorption maximeum is at 545nm. This method has higher senitivity and better repeatability than that aluminon method. The proposed method is suitable for the determination of aluminium in the range of 0.01%-5% in Lead-Calcium-aluminium ternary alloy.%在六次甲基四胺缓冲溶液(pH5~6)介质中,铝与铬天青S生成 水溶性的紫红色络合物,其λmax=545nm。本法较铝试剂法具有较高 的灵敏度,并重复性好,适用于铅钙铝三元合金中0.01%~5%铝的 测定。

  20. ZL101泡沫铝合金制备技术研究%Study on Preparation Technology of ZL101 Foamed Aluminium Alloy

    Institute of Scientific and Technical Information of China (English)

    李敬民; 周丹晨; 刘建辉; 黄姝珂

    2011-01-01

    以ZL101为基体材料,利用熔体发泡法制备泡沫铝合金,通过控制增粘温度、增粘物质和发泡物质的加入方式、发泡温度等关键参数获得稳定的制备工艺参数.实验结果表明,在660℃增粘效果要好于在700℃以上增粘;TiH2采用铝箔包裹方式加入可以有效减少加入过程的烧损量;加入发泡剂过程中使用带有下旋压力的双层折叶搅拌浆有利于将TiH2快速分散均匀和减小泡沫铝底部实心层;发泡温度为645℃时可以获得孔径较均匀的泡沫铝合金.%ZL101 foamed aluminium alloy was prepared by melt foaming method. The stabilized technological parameters was got by controlling the key factors such as the temperature of adding viscosity increaser, the way of adding viscosity increaser and blister, the temperature of foaming and so on. The results show that adding viscosity increaser at 660 ℃ is better than above 700 ℃. Packed TiH2 with aluminium foil is effective to reduce TiH2 burning loss. It is useful to break up powder of TiH2 quickly and decrease the solid thickness of foamed aluminium alloy using double-deck stirring paddle with downward stress. When the foaming temperature is 645 ℃, it could get uniform aperture aluminium alloy.

  1. Investigation of photocatalytic activity of titanium dioxide coating deposited on aluminium alloy substrate by plasma technique

    DEFF Research Database (Denmark)

    Daviðsdóttir, Svava; Soyama, Juliano; Dirscherl, Kai

    2011-01-01

    Nowadays, there is an increased need for functionalized surfaces with self-cleaning and antibacterial properties. Titanium dioxide (TiO2) in the anatase crystalline structure is one of the most powerful photocatalytic materials available today, which can provide above functionalities. The photoca......Nowadays, there is an increased need for functionalized surfaces with self-cleaning and antibacterial properties. Titanium dioxide (TiO2) in the anatase crystalline structure is one of the most powerful photocatalytic materials available today, which can provide above functionalities...... have wide spread technological applications, where a combination of self-cleaning properties has a huge business potential. The results presented in this paper demonstrate superior photocatalytic properties of TiO2 coated aluminium compared to nano-scale TiO2 coating on glass substrate. The thickness...

  2. Investigations on temperature distribution in welding of Aluminium alloys to steel using FEM

    Directory of Open Access Journals (Sweden)

    K. S. Ashraff Ali

    2015-01-01

    Full Text Available This research study focuses on the objective to establish an analytical model for determining the thermal distribution during friction stir welding (FSW, based on different assumptions of the contact condition between the rotating tool surface and the weld piece. The material flow and heat generation are characterized by the contact conditions at the interface, and are described as sliding, sticking or partial sliding/sticking. The analytical expression for the heat generation is a modification of previous analytical models known from the literature and accounts for both conical surfaces and different contact conditions. Aluminium metal matrix composites and steel 304 (dissimilar material joining is being used for this study. Three dimensional Finite Element Models have been developed to visualize the temperature distribution across the butt ends of the plates. The results are validated with the experimental results reported in the literature. The result reveals that there exists a good coherence between experimental and simulated results.

  3. Mechanisms of the porosity formation during the fiber laser lap welding of aluminium alloy

    Directory of Open Access Journals (Sweden)

    J. Wang

    2015-10-01

    Full Text Available When joining the aluminum alloys, one of the biggest challenges is the formation of porosity, which deteriorates mechanical properties of welds. In this study, the lap welding was conducted on an aluminum alloy 5754 metal sheets with a thickness of 2 mm. The effects of various laser welding parameters on the weld quality were investigated. The porosity content was measured by X-ray inspections. The key is to control the solidification duration of molten pool. When the solidification duration of molten pool is large enough, more bubbles can escape from the molten pool and less remain as porosity.

  4. Galvanostatic response of AA2024 aluminium alloy in 3.5% NaCl solution

    Indian Academy of Sciences (India)

    U DONATUS; G E THOMPSON

    2016-10-01

    Galvanostatic responses of AA2024T3 alloy in de-aerated and naturally aerated 3.5% NaCl solution have been investigated. In the de-aerated condition, two distinct stages of polarization were revealed. From the first stage, the relationships between the pitting incubation time, pitting potential and applied current density for AA2024T3 alloy in the de-aerated condition were established. The curves in the aerated condition showed no particular incubation time-applied current density relationship.

  5. T5 heat treatment of semi-solid metal processed aluminium alloy F357

    CSIR Research Space (South Africa)

    Moller, H

    2009-04-01

    Full Text Available out in many applications due to the carcinogenic effects of beryllium, particularly at higher concentrations used during make-up of the alloy. In Al-Si-Mg alloys containing an excess of silicon, the decomposition of the supersaturated solid solution.... However, spheroidisation of the silicon particles [2] is not achieved in A356-T5 with deleterious effects on ductility and lower strength obtained in A356-T5 if compared to A356-T6 due to less supersaturation of strengthening solutes before artificial...

  6. Behaviour and modelling of aluminium alloy AA6060 subjected to a wide range of strain rates and temperatures

    Directory of Open Access Journals (Sweden)

    Vilamosa Vincent

    2015-01-01

    Full Text Available The thermo-mechanical behaviour in tension of an as-cast and homogenized AA6060 alloy was investigated at a wide range of strains (the entire deformation process up to fracture, strain rates (0.01–750 s−1 and temperatures (20–350 ∘C. The tests at strain rates up to 1 s−1 were performed in a universal testing machine, while a split-Hopkinson tension bar (SHTB system was used for strain rates from 350 to 750 s−1. The samples were heated with an induction-based heating system. A typical feature of aluminium alloys at high temperatures is that necking occurs at a rather early stage of the deformation process. In order to determine the true stress-strain curve also after the onset of necking, all tests were instrumented with a digital camera. The experimental tests reveal that the AA6060 material has negligible strain-rate sensitivity (SRS for temperatures lower than 200 ∘C, while both yielding and work hardening exhibit a strong positive SRS at higher temperatures. The coupled strain-rate and temperature sensitivity is challenging to capture with most existing constitutive models. The paper presents an outline of a new semi-physical model that expresses the flow stress in terms of plastic strain, plastic strain rate and temperature. The parameters of the model were determined from the tests, and the stress-strain curves from the tests were compared with the predictions of the model. Good agreement was obtained over the entire strain rate and temperature range.

  7. Application of Kaplan-Meier analysis in reliability evaluation of products cast from aluminium alloys

    Directory of Open Access Journals (Sweden)

    J. Szymszal

    2010-04-01

    Full Text Available The article evaluates the reliability of AlSi17CuNiMg alloys using Kaplan-Meier-based technique, very popular as a survival estimation tool in medical science. The main object of survival analysis is a group (or groups of units for which the time of occurrence of an event (failure taking place after some time of waiting is estimated. For example, in medicine, the failure can be patient’s death. In this study, the failure was the specimen fracture during a periodical fatigue test, while the survival time was either the test duration to specimen failure (complete observations, or the test end time (censored observations. The parameters of theoretical survival function were estimated with procedures based on the method of least squares, while typical survival time distribution followed either an exponential or two-parameter Weibull distribution. The goodness of fit of a model survival function was estimated with an incremental chi-square test, based on the values of the log likelihood ratio. The effect of alloy processing history on the run of a survival function was examined. The factors shaping the alloy processing history included: mould type (sand or metal mould, alloy modification process, and heat treatment type (solution heat treatment and ageing.

  8. Structure and tensile/wear properties of microarc oxidation ceramic coatings on aluminium alloy

    Institute of Scientific and Technical Information of China (English)

    魏同波; 阎逢元; 刘维民; 田军

    2004-01-01

    Thick and hard ceramic coatings were prepared on the Al-Cu-Mg alloy by microarc oxidation in alkali-silicate electrolytic solution. The thickness and microhardness of the oxide coatings were measured. The influence of current density on the growth rate of the coating was examined. The microstructure and phase composition of the coatings were investigated by means of scanning electron microscopy, energy dispersive spectroscopy, and X-ray diffraction. Moreover, the tensile strength of the Al alloy before and after microarc oxidation treatment were tested,and the fractography and morphology of the oxide coatings were observed using scanning electron microscope. It is found that the current density considerably influences the growth rate of the microarc oxidation coatings. The oxide coating is mainly composed of α-Al2 O3 and γ-Al2 O3, while high content of Si is observed in the superficial layer of the coating. The cross-section microhardness of 120 μm thick coating reaches the maximum at distance of 35 μm from the substrate/coating interface. The tensile strength and elongation of the coated Al alloy significantly decrease with increasing coating thickness. The microarc oxidation coatings greatly improve the wear resistance of Al alloy,but have high friction coefficient which changes in the range of 0.7 - 0.8. Under grease lubricating, friction coefficient is only 0.15 and wear loss is less than 1/10 of the loss under dry friction.

  9. Appearance of anodised aluminium: Effect of alloy composition and prior surface finish

    DEFF Research Database (Denmark)

    Aggerbeck, Martin; Canulescu, Stela; Dirscherl, Kai

    2014-01-01

    prior to anodising were analysed using scanning electron microscopy and atomic force microscopy. The optical appearance of the anodised surface with and without sealing was investigated using a photography setup, photospectrometry and bidirectional reflectance distribution function. It was found...... appearance was kept for alloys of high purity. Sealing made the specular reflection of the mechanically polished specimens more distinct....

  10. Evaluation of surface chemical segregation of semi-solid cast aluminium alloy A356

    CSIR Research Space (South Africa)

    Govender, G

    2008-01-01

    Full Text Available be minimized. The surface liquid segregation phenomenon was investigated on high pressure die cast (HPDC) A356 alloy. SSM slurries were prepared using the CSIR Rheocasting System and plates of 4mm × 80mm × 100mm were HPDC. The chemical composition depth profile...

  11. Effect of united refining and modification on mechanical properties of A356 aluminium alloys

    Institute of Scientific and Technical Information of China (English)

    ZUO Xiu-rong; ZHONG Zhi-guo

    2006-01-01

    The refining and modification effect of Ti (from GRAI), B, Sr and RE (cerium-riched mixtures of rare earth) on the mechanical properties of A356 aluminum alloys under T5 and T6 treatment condition were studied by OM, SEM, EDAX, etc. It is found that the addition of RE to A356 alloys containing Ti and/or B and Sr makes strength and elongation increase in T6 treatment,but make elongation decrease in T5 treatment, at the same time, the long axis of α(Al) grain structure decreases and the mean diameters of silicon particles increase with RE additions increasing. Grain refining with 0.01%Ti plus 0.03% B makes the dendrite α(Al) grain structure transform into equiaxed structure, resulting in obvious increase of elongation percentage. The mean diameters of silicon particles in T5 treatment are smaller than that in T6 treatrnent. Roundness of silicon particles in T5 treatment is higher than that in T6 treatment. A356 alloys modified and refined with Ti, B and Sr obtain the best mechanical properties in T5 treatment,however, the alloys with Ti, B, RE and Sr additions obtain the best mechanical properties in T6 treatment.

  12. Study of Simulated Temperature of Butt Joint during Friction Stir Welding Of Aluminium Alloy by Using Hyperworks

    Directory of Open Access Journals (Sweden)

    Mohd Anees Siddiqui

    2015-01-01

    Full Text Available Friction stir welding (FSW is one of the latest welding technology that utilizes a special tool for generation of frictional heat in the work piece by its rotation due to which joining occurs without melting of metal. For this reason friction stir welding lies under the category of solid state joining. A part from experimental work, there is large space to work on simulation of FSW by using simulation tools. In the present paper, simulation of friction stir welding of aluminium alloy AA-6061 is done by using HyperWeld module of Altair HyperWorks. The virtual experiment of friction stir welding is conducted for variable tool rotational speeds with constant travelling speed and study of simulation results of variation in temperature distribution along the weld line of butt joint is done. The results of simulation shows that the temperature is symmetrically distributed along the weld line. It is observed that the maximum temperature along the weld line increases with the increase in rotational speed. It is also observed that the temperature at advancing side is greater that retreating side.

  13. Influence of process parameters on physical dimensions of AA6063 aluminium alloy coating on mild steel in friction surfacing

    Directory of Open Access Journals (Sweden)

    B. Vijaya Kumar

    2015-09-01

    Full Text Available An attempt is made in the present study to obtain the relationships among process parameters and physical dimensions of AA6063 aluminium alloy coating on IS2062 mild steel obtained through friction surfacing and their impact on strength and ductility of the coating. Factorial experimental design technique was used to investigate and select the parameter combination to achieve a coating with adequate strength and ductility. Spindle speed, axial force and table traverse speed were observed to be the most significant factors on physical dimensions. It was observed that the thickness of the coating decreased as the coating width increased. In addition, the width and thickness of the coatings are higher at low and high torques. At intermediate torque values, when the force is high, the width of the coating is high, and its thickness is thin; and when the force is low, the width and thickness are low. The interaction effect between axial force (F – table traverse speed (Vx and spindle speed (N – table traverse speed (Vx produced an increasing effect on coating width and thickness, but other interactions exhibited decreasing influence. It has also been observed that sound coatings could be obtained in a narrow set of parameter range as the substrate-coating materials are metallurgically incompatible and have a propensity to form brittle intermetallics.

  14. Experimental investigation on the effects of cooling system on surface quality in high speed milling of an aluminium alloy

    Science.gov (United States)

    Chirita, B.; Tampu, N. C.; Brabie, G.; Radu, M. C.

    2016-08-01

    Surface quality is often an important feature of industrial products, not only from the impact it has on the aesthetic aspect but also for the functional role of the parts. High quality surface increases corrosion resistance, assures a longer life cycle for the product and lowers the wear. For a machined part, surface quality is influenced by a series of factors such as the material of the part, the process type, tool geometry, cutting parameters or the cooling system. The choice of the cooling system is especially important, taking into account that the proper conditions will not only assure a superior surface quality, but will also lower the costs and reduce the environmental impact and health risks. The present study aims to investigate the performance of the cooling system and the effect of the cutting parameters on the characteristics of the surfaces resulted from high speed face milling of some parts made of Al 7050-T7451 aluminium alloy. Dry cutting conditions and minimum quantity lubrication (MQL) where used. The results were analysed using analysis of variance (ANOVA).

  15. Effect of Processing Parameters on the Protective Quality of Electroless Nickel-Phosphorus on Cast Aluminium Alloy

    Directory of Open Access Journals (Sweden)

    Olawale Olarewaju Ajibola

    2015-01-01

    Full Text Available The effects of temperature, pH, and time variations on the protective amount and quality of electroless nickel (EN deposition on cast aluminium alloy (CAA substrates were studied. The temperature, pH, and plating time were varied while the surface condition of the substrate was kept constant in acid or alkaline bath. Within solution pH of 5.0–5.5 range, the best quality is obtained in acid solution pH of 5.2. At lower pH (5.0–5.1, good adhesion characterised the EN deposition. Within the range of plating solution pH of 7.0 to 11.5, the highest quantity and quality of EN deposition are obtained on CAA substrate in solution pH of 10.5. It is characterised with few pores and discontinuous metallic EN film. The quantity of EN deposition is time dependent, whereas the adhesion and brightness are not time controlled. The best fit models were developed from the trends of result data obtained from the experiments. The surface morphologies and the chemical composition of the coating were studied using the Jeol JSM-7600F field emission scanning electron microscope.

  16. Effect of the homogenisation conditions on the extrudability and high temperature fracture resistance of AA6063 aluminium alloy

    Energy Technology Data Exchange (ETDEWEB)

    Lassance, D.; Pardoen, T.; Ryelandt, L.; Delannay, F. [Univ. catholique de Louvain, Dept. des Sciences des Materiaux et des Procedes, PCIM, Louvain-La-Neuve (Belgium); Dille, J.; Delplancke, J.L. [Univ. Libre de Bruxelles, Service Science des Materiaux et Electrochimie, Bruxelles (Belgium); Ryckeboer, M. [Remi Claeys International Services, Lichtervelde (Belgium)

    2003-07-01

    Homogenisation is an essential step in the preparation of aluminium billets for extrusion. It is designed to produce an homogeneous solid solution and to transform the {beta}-Al{sub 5}FeSi particles to the more equiaxed and thus more acceptable cubic {alpha}-Al{sub 12}(Fe{sub x},Mn{sub 1-x}){sub 3}Si variety. The effect of the homogenisation conditions on high temperature surface damage and fracture is investigated through full scale industrial extrusion experiments on AlMgSi alloy. The transformation of AlFeSi intermetallic particles from the {beta}-Al{sub 5}FeSi thin plate like shape to the more rounded {alpha}-Al{sub 12}(Fe,Mn){sub 3}Si form, quantified by EDS measurements, is shown to postpone the formation of surface defects. Transmission electron microscopy (TEM) analysis of extruded samples close to the location of extrusion defects, reveals that damage initiates by microcracks within the brittle {beta}-Al{sub 5}FeSi particles or due to incipient melting caused by the eutectic transformation Al+{beta}-Al{sub 5}FeSi+Si{yields}Liquid at 578 C. These microcracks open by plastic deformation around the cracked brittle phase and, after sufficient growth, coalesce into a large crack. (orig.)

  17. Effect of temperature and frequency of dynamic loading in the viscoelastic properties of aluminium alloy 7075-T6

    Energy Technology Data Exchange (ETDEWEB)

    Rojas, Jose I.; Aguiar, Albert; Crespo, Daniel [Escola d' Enginyeria de Telecomunicacio i Aeroespacial de Castelldefels (EPSC), Universitat Politecnica de Catalunya (UPC Barcelona Tech), Castelldefels, Barcelona (Spain)

    2011-11-15

    The viscoelastic response of a material offers an alternative method for analyzing its microstructure, phase transformations and fatigue behaviour. In this work, the viscoelastic properties of commercial aluminium alloy (AA) 7075-T6 are studied with a Dynamic-Mechanical Analyzer (DMA), and results are combined with Transmission Electron Microscopy (TEM) and Differential Scanning Calorimetry (DSC) data. In accordance with this analysis, we propose an analytical model for the storage modulus E' as a function of temperature, frequency of the dynamic loading and the concentration of Guinier-Preston Zones (GPZ). The latter parameter is obtained as a function of temperature after integration and fitting of the model. It is shown that the proposed model fits the experimental data for the storage modulus reasonably well in the prescribed region, and that this fact supports the hypothesis that the change in the storage modulus slope at about 130-160 C is due to GPZ decomposition. (copyright 2011 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim) (orig.)

  18. Estimating multivariate response surface model with data outliers, case study in enhancing surface layer properties of an aircraft aluminium alloy

    Science.gov (United States)

    Widodo, Edy; Kariyam

    2017-03-01

    To determine the input variable settings that create the optimal compromise in response variable used Response Surface Methodology (RSM). There are three primary steps in the RSM problem, namely data collection, modelling, and optimization. In this study focused on the establishment of response surface models, using the assumption that the data produced is correct. Usually the response surface model parameters are estimated by OLS. However, this method is highly sensitive to outliers. Outliers can generate substantial residual and often affect the estimator models. Estimator models produced can be biased and could lead to errors in the determination of the optimal point of fact, that the main purpose of RSM is not reached. Meanwhile, in real life, the collected data often contain some response variable and a set of independent variables. Treat each response separately and apply a single response procedures can result in the wrong interpretation. So we need a development model for the multi-response case. Therefore, it takes a multivariate model of the response surface that is resistant to outliers. As an alternative, in this study discussed on M-estimation as a parameter estimator in multivariate response surface models containing outliers. As an illustration presented a case study on the experimental results to the enhancement of the surface layer of aluminium alloy air by shot peening.

  19. Effects of cathodic voltages on structure and wear resistance of plasma electrolytic oxidation coatings formed on aluminium alloy

    Energy Technology Data Exchange (ETDEWEB)

    Li, Qingbiao [State Key Laboratory of Solid Lubrication, Lanzhou Institute of Chemical Physics, Chinese Academy of Sciences, Lanzhou 730000 (China); School of Science, Lanzhou University of Technology, Lanzhou 730050 (China); Liang, Jun, E-mail: jliang@licp.cas.cn [State Key Laboratory of Solid Lubrication, Lanzhou Institute of Chemical Physics, Chinese Academy of Sciences, Lanzhou 730000 (China); Liu, Baixing; Peng, Zhenjun [State Key Laboratory of Solid Lubrication, Lanzhou Institute of Chemical Physics, Chinese Academy of Sciences, Lanzhou 730000 (China); Wang, Qing [School of Science, Lanzhou University of Technology, Lanzhou 730050 (China)

    2014-04-01

    Highlights: • The PEO coating growth rate increased with the cathodic voltage increasing. • Higher cathodic voltage resulted in more compact coating structure. • The compact structure led to low surface roughness and high wear resistance. - Abstract: Plasma electrolytic oxidation (PEO) coatings were prepared on aluminium alloy using pulsed bipolar power supply at constant anodic voltage and different cathodic voltages. The samples were prepared to attain the same coating thickness by adjusting the processing time. The scanning electron microscope (SEM), energy dispersive spectrometer (EDS), X-ray diffraction (XRD) and tribometer were employed to investigate the microstructure, element content, phase composition and wear resistance of the coatings respectively. It was found that the coating growth rate enhanced obviously and the coatings exhibited a more compact structure with thicker inner layer and lower surface roughness when the cathodic voltage increased. The coatings were mainly composed of crystalline γ-Al{sub 2}O{sub 3} and amorphous silicate oxides and their relative content changed with the cathodic voltage. The wear resistance of the coatings improved significantly with the increase of cathodic voltage.

  20. Impact resistance and hardness modelling of Aluminium alloy welds using square-headed friction-stir welding tool

    Science.gov (United States)

    Sudhakar, U.; Srinivas, J., Dr.

    2016-02-01

    This paper proposes modelling and optimization issues relating to friction-stir welding process of aluminium alloys. A specially prepared SS tool of square headed pin profile with cylindrical shoulder is used with a vertical milling machine. Effects of process variables including tool rotation and tool velocity on the weld performance are studied in terms of impact strength and hardness. Three different rotational motions and three welding speeds (feeds) of tool are considered at constant axial load (depth of cut) condition and altogether nine experiments are conducted on a vertical milling machine with specially prepared fixture. Each weld sample is then tested for its impact strength (IS) and hardness independently. A model is developed to correlate the relations between the hardness/impact strength with tool rotation and weld speed using neural networks. The optimized process conditions are predicted to improvise the impact strength and hardness of the weld. Further, the morphology of the weld is studied using SEM to know the material flow characteristics.

  1. Microstructure and mechanical properties of similar and dissimilar joints of aluminium alloy and pure copper by friction stir welding

    Directory of Open Access Journals (Sweden)

    V.C. Sinha

    2016-09-01

    Full Text Available In the present study, the microstructure and mechanical properties of similar and dissimilar friction stir welded joints of aluminium alloy (AlA and pure copper (Cu were evaluated at variable tool rotational speeds from 150 to 900 rpm in steps of 150 rpm at 60 mm/min travel speed and constant tilt angle 2°. The interfacial microstructures of the joints were characterised by optical and scanning electron microscopy. The Al4Cu9, AlCu, Al2Cu and Al2Cu3 intermetallic compounds have been observed at the interface and stir zone region of dissimilar Al/Cu FSWed joints. Variation in the grain size was observed in the stir zone depending upon the heat input value. Axial force, traverse force and torque value were analysed with variation in tool rotational speed. Residual stresses were measured at the stir zone by X-ray diffraction technique. Maximum ultimate tensile strength of ∼75% of AlA strength for AlA–AlA joints has been obtained at 750 rpm and for Cu–Cu joint tensile strength of ∼100% of tensile strength of Cu was obtained at 300 rpm. However, for Cu–AlA joint when processed at 600 rpm tool rotational speed achieved maximum ultimate tensile strength of ∼77% of AlA.

  2. Isoelectronic Substitutions and Aluminium Alloying in the Ta-Nb-Hf-Zr-Ti High-Entropy Alloy Superconductor

    OpenAIRE

    von Rohr, Fabian O.; Cava, Robert J.

    2017-01-01

    High-entropy alloys (HEAs) are a new class of materials constructed from multiple principal elements statistically arranged on simple crystallographic lattices. Due to the large amount of disorder present, they are excellent model systems for investigating the properties of materials intermediate between crystalline and amorphous states. Here we report the effects of systematic isoelectronic replacements, using Mo-Y, Mo-Sc, and Cr-Sc mixtures, for the valence electron count 4 and 5 elements i...

  3. People in Foundry Field of China

    Institute of Scientific and Technical Information of China (English)

    2009-01-01

    @@ Mr. Song Caifei was born in 1929 in Liuyang of Hunan Province, and started to work in 1949. Later he was sent to former Dalian Industry Russian Academy to learn Russian, in order to go to the former Soviet Union studying professional technology for nonferrous alloys. However, according to the agreement of Sino-Germany technical cooperation, he was instead admitted to ZIG-Leipzig Foundry College in Germany majoring in special casting to onslaught die casting, and completed his study at the end of 1956.

  4. The Effect of Dynamic Compression on the Evolution of Microstructure in Aluminium and its Alloys

    Directory of Open Access Journals (Sweden)

    Leszczyńska-Madet B.

    2013-12-01

    Full Text Available W pracy przedstawiono wyniki badań mikrostruktury i wybranych właściwości polikrystalicznego aluminium i jego stopów: AlMg5, AlCu4Zr0.5, AlZn6Mg2.5CuZr ściskanych dynamicznie za pomocą młota spadowego. Próbki odkształcano w zakresie odkształceń rzeczywistych = 0-0.62 z prędkością odkształcenia z zakresu 1.77-6.06x102 s-1. Na tak odkształconych materiałach przeprowadzono pomiar mikrotwardości oraz badania mikrostruktury przy zastosowaniu transmisyjnego mikrosko- pu elektronowego (TEM i mikroskopu świetlnego (LM, dodatkowo przeprowadzono pomiar dezorientacji w mikroobszarach metodą linii Kikuchiego przy zastosowaniu oprogramowania KILIN. Cechą charakterystyczną mikrostruktury badanych materiałów były licznie obserwowane pasma i pasma ścinania. Wyniki uzyskane przy zastosowaniu transmisyjnego mikroskopu elektronowego dowiodły występowania licznych mikropasm i mikro- pasm ścinania, które w zależności od materiału przebiegały na tle różnych układów dyslokacyjnych. Obserwowane mikropasma wykazywały dużą dezorientację względem osnowy. Stwierdzono wzajemnie przecinanie się mikropasm. W zakresie wyższych wartości odkształcenia, mikropasma wypełniały niemal całą objętość próbek. Zaobserwowano zależność zmniejszania się średniej szerokości i mikropasm wraz ze wzrostem wielkości odkształcenia i prędkości odkształcenia. Praca miała na celu określenie wpływu prędkości odkształcenia (1.77x10' - 6.06xl02s_1 na możliwość rozdrobnienia mikrostruktury polikrystalicznego aluminium A199.5 i jego stopów (AlMg5, AlCu4Zr0.5, AlZn6Mg2.5CuZr odkształcanych w procesie dynamicznego ściskania za pomocą młota spadowego.

  5. Study of corrosion of aluminium alloys of nuclear purity in ordinary water, пart one

    Directory of Open Access Journals (Sweden)

    Pešić Milan P.

    2004-01-01

    Full Text Available Effects of corrosion of aluminum alloys of nuclear purity in ordinary water of the spent fuel storage pool of the RA research reactor at VINČA Institute of Nuclear Sciences has been examined in the frame work of the International Atomic Energy Agency Coordinated Research Project "Corrosion of Research Reactor Aluminum-Clad Spent Fuel in Water" since 2002. The study presented in this paper comprises activities on determination and monitoring of chemical parameters and radio activity of water and sludge in the RA spent fuel storage pool and results of the initial study of corrosion effects obtained by visual examinations of surfaces of various coupons made of aluminum alloys of nuclear purity of the test racks exposed to the pool water for a period from six months to six years.

  6. EVOLUTION OF AS-CAST MICROSTRUCTURES OF 356 ALUMINIUM ALLOY CAST BY LIQUIDUS CASTING

    Institute of Scientific and Technical Information of China (English)

    J. Dong; G.M. Lu; J.Z. Cui; Z.H. Zhao

    2003-01-01

    A new method (liquidus casting) was used for 356 Al alloy semi-solid slurry mak-ing. The structures of 356 Al alloy cast by a Fe mould and semi-continuous castingmachine at different temperatures were investigated. How the globular grains formwas also discussed. The results show that either being cast by single Fe mould orsemi-continuous machine, the microstructures are not conventional dendrites but fineand net-globular grains. The average grain size is smaller than 30μm and suitableenough for thixoforming, meanwhile it can improve the mechanical properties of fol-lowing products. Under the suitable casting velocity and cooling intensity, most ofglobal grains prolong their global growth and collide with each other before dendriticgrowth because of the large amount of the nucleation sites.

  7. EVOLUTION OF AS—CAST MICROSTRUCTURES OF 356 ALUMINIUM ALLOY CAST BY LIQUIDUS CASTING

    Institute of Scientific and Technical Information of China (English)

    J.Dong; G.M.Lu; 等

    2003-01-01

    A new method (liquidus casting)was used for 356 Al alloy semi-solid slurry mak-ing.The structures of 356 Al alloy cast by a fe mould and semi-continuous casting machine at different temperatures were inves tigated.How the globular grains form was qlso discussed.The results show that either being cast by single Fe mould or semi-continuous machine,the microstructures are not conventional dendrites but fine and net-globular grains.The average grain size is smaller than 30μm and suitable enough for thixoforming,meanwhile it can improve the mechanical properties of fol-lowing products.Under the suitable casting velocity and cooling intensity,most of global grains prolong their global browth and collide with each other before dendritic growth because of the large amount of the nucleation sites.

  8. Continuous sodium modification of nearly-eutectic aluminium alloys. Part II. Experimental studiem

    Directory of Open Access Journals (Sweden)

    Białobrzeski A.

    2007-01-01

    Full Text Available One of the possible means of continuous sodium modification of nearly-eutectic alloys may be continuous electrolysis of sodium compounds (salts, taking place directly in metal bath (in the crucible. For this process it is necessary to use a solid electrolyte conducting sodium ions. Under the effect of the applied direct current voltage, sodium salt placed in a retort made from the solid electrolyte undergoes dissociation, and next - electrolysis. The retort is immersed in liquid metal. The anode is sodium salt, at that temperature occurring in liquid state, connected to the direct current source through, e.g. a graphite electrode, while cathode is the liquid metal. Sodium ions formed during the sodium salt dissociation and electrolysis are transported through the wall of the solid electrolyte (the material of the retort and in contact with liquid alloy acting as a cathode, they are passing into atomic state, modifying the metal bath.

  9. Corrosion behaviour of ion implanted aluminium alloy in 0.1 M NaCl electrolyte

    Energy Technology Data Exchange (ETDEWEB)

    Chu, J.W.; Evans, P.J. [Australian Nuclear Science and Technology Organisation, Lucas Heights, NSW (Australia); Sood, D.K. [Royal Melbourne Inst. of Tech., VIC (Australia)

    1993-12-31

    Aluminum and its alloys are widely used in industry because of their light weight, high strength and good corrosion resistance which is due to the formation of a protective oxide layer. However, under saline conditions such as those encountered in marine environments, this group of metals are vulnerable to localised degradation in the form of pitting corrosion. This type of corrosion involves the adsorption of an anion, such as chlorine, at the oxide solution interface. Ion implantation of metal ions has been shown to improve the corrosion resistance of a variety of materials. This effect occurs : when the implanted species reduces anion adsorption thereby decreasing the corrosion rate. In this paper we report on the pitting behavior of Ti implanted 2011 Al alloy in dilute sodium chloride solution. The Ti implanted surfaces exhibited an increased pitting potential and a reduced oxygen uptake. 5 refs., 3 figs.

  10. Researches and studies regarding brazed aluminium alloys microstructure used in aeronautic industry

    Directory of Open Access Journals (Sweden)

    A. Dimitrescu

    2015-04-01

    Full Text Available Brazing is applied to the merge of the pieces which are most required, tensile strength of the solder can reach high values. By brazing there can be assembled pieces of most metals and ferrous and nonferrous alloys, with high melting temperature. This paper presents an analysis of the microstructure of materials from a brazed merge of aluminum alloy L103 which is often used to produce pieces of aeronautical industry. Brazing material was performed using several technologies, and after examination of the microstructure of materials from the merge area it was established as optimal technology the technology which consist of pickling in Aloclene 100 solution with the deposition of filler material on both sides of the base material and the use of spectral acetylene and neutral flame.

  11. Effect of selected microadditives on the mechanical properties of aluminium alloys

    Directory of Open Access Journals (Sweden)

    Rzadkosz S.

    2007-01-01

    Full Text Available The effect of iron impurities on microstructure and mechanical properties of cast Al-Cu and Al-Zn-Mg alloys was discussed. The role of iron in the process of solutioning and ageing of these alloys was described. Basing on the results of investigations, a comparative analysis was made to disclose the effect of low content (microadditives of the elements, like Mn, Ti, Zr, B, Cr, Ni, Zn, Sn, Cd, In, Mg, Sb, and Ag on the primary structure of castings, mainly on the morphology of iron-bonding intermetallic phases. The studies also allowed for an effect of these elements on dispersion hardening of the examined alloys, reflected in an improvement of the principal mechanical properties (Rm, A5, HV, and on the kinetics of ageing. Tin, cadmium and indium, added in an amount of 0,1 – 0,15 %, were reported to have the strong-est effect on the process of dispersion hardening. Beneficial effect on the morphology of iron phases have manganese, chromium and nickel.

  12. Emission of nanoparticles during friction stir welding (FSW) of aluminium alloys.

    Science.gov (United States)

    Gomes, J F; Miranda, R M; Santos, T J; Carvalho, P A

    2014-01-01

    Friction stir welding (FSW) is now well established as a welding process capable of joining some different types of metallic materials, as it was (1) found to be a reliable and economical way of producing high quality welds, and (2) considered a "clean" welding process that does not involve fusion of metal, as is the case with other traditional welding processes. The aim of this study was to determine whether the emission of particles during FSW in the nanorange of the most commonly used aluminum (Al) alloys, AA 5083 and AA 6082, originated from the Al alloy itself due to friction of the welding tool against the item that was being welded. Another goal was to measure Al alloys in the alveolar deposited surface area during FSW. Nanoparticles dimensions were predominantly in the 40- and 70-nm range. This study demonstrated that microparticles were also emitted during FSW but due to tool wear. However, the biological relevance and toxic manifestations of these microparticles remain to be determined.

  13. Investigation on mechanical behaviour of ECAPed 2A12 aluminium alloy

    Directory of Open Access Journals (Sweden)

    Wang Cun-xian

    2015-01-01

    Full Text Available In the present work, the uniaxial compressive behavior of aluminum alloy processed by equal channel angular pressing (ECAP for 1–8 passes are investigated experimentally under both quasi-static and dynamic loading conditions via an electronic universal testing machine with a maximum load capacity of 10KN and the split Hopkinson pressure bar (SHPB. The strain hardening rate as well as strain rate sensitivity the ECAPed with different passes have been determined and compared with annealed coarse grained counterpart. The experimental results show a continuously increase of both flow stress and strain rate sensitivity for the aluminum alloy subjected to ECAP process as the pressing pass number increasing. It is proposed that the reduction in grain size plays an important role in the enhancement of flow stress and strain rate sensitivity. However, the strain hardening rate of the ECAPed materials decreases remarkably. Meanwhile, compressive experiments at elevated temperatures indicate the temperature sensitivity of the material increases as the grain size is refined into fine grain regime. Based on thermal activation theory, it is proposed that the enhanced temperature and strain rate sensitivity of ECAPed aluminum alloy can be related to the reduction in activation volume due to grain refinement.

  14. Investigation of the controlled atmosphere of semisolid metal processing of A356 aluminium alloy

    Energy Technology Data Exchange (ETDEWEB)

    Kolahdooz, A.; Nourouzi, S.; Bakhshi, M.; Hosseinipour, S. J. [Babol University of Technology, Babol (Iran, Islamic Republic of)

    2014-10-15

    The cooling slope (CS) method is one of the semi-solid methods in which the molten alloy with a suitable amount of superheat is poured on a cooling slope to achieve a fine and non-dendritic structure. After pouring, the melt, which becomes semisolid at the end of the plate, is subsequently poured into a cylindrical steel mold with different mold temperatures. Also, the process has been done in different cooling slopes and different cooling lengths. This work, at first discusses the effect of these parameters on the final microstructure of A356 aluminum alloy and then the effect of the controlled atmosphere is discussed. Also, in this research, the advantages of using the controlled atmosphere system are discussed by tests such as XRD, SEM and ultrasonic test. Results indicate that the pouring temperature, mold temperature, cooling slope and cooling length have significant effects on the size and morphology of α-Al phase. Also, the controlled atmosphere could optimize the process as well and increase the mechanical properties of alloy.

  15. Computational prediction of the refinement of oxide agglomerates in a physical conditioning process for molten aluminium alloy

    Science.gov (United States)

    Tong, M.; Jagarlapudi, S. C.; Patel, J. B.; Stone, I. C.; Fan, Z.; Browne, D. J.

    2015-06-01

    Physically conditioning molten scrap aluminium alloys using high shear processing (HSP) was recently found to be a promising technology for purification of contaminated alloys. HSP refines the solid oxide agglomerates in molten alloys, so that they can act as sites for the nucleation of Fe-rich intermetallic phases which can subsequently be removed by the downstream de-drossing process. In this paper, a computational modelling for predicting the evolution of size of oxide clusters during HSP is presented. We used CFD to predict the macroscopic flow features of the melt, and the resultant field predictions of temperature and melt shear rate were transferred to a population balance model (PBM) as its key inputs. The PBM is a macroscopic model that formulates the microscopic agglomeration and breakage of a population of a dispersed phase. Although it has been widely used to study conventional deoxidation of liquid metal, this is the first time that PBM has been used to simulate the melt conditioning process within a rotor/stator HSP device. We employed a method which discretizes the continuous profile of size of the dispersed phase into a collection of discrete bins of size, to solve the governing population balance equation for the size of agglomerates. A finite volume method was used to solve the continuity equation, the energy equation and the momentum equation. The overall computation was implemented mainly using the FLUENT module of ANSYS. The simulations showed that there is a relatively high melt shear rate between the stator and sweeping tips of the rotor blades. This high shear rate leads directly to significant fragmentation of the initially large oxide aggregates. Because the process of agglomeration is significantly slower than the breakage processes at the beginning of HSP, the mean size of oxide clusters decreases very rapidly. As the process of agglomeration gradually balances the process of breakage, the mean size of oxide clusters converges to a

  16. Manganese exposure in foundry furnacemen and scrap recycling workers

    DEFF Research Database (Denmark)

    Lander, F; Kristiansen, J; Lauritsen, Jens

    1999-01-01

    Cast iron products are alloyed with small quantities of manganese, and foundry furnacemen are potentially exposed to manganese during tapping and handling of smelts. Manganese is a neurotoxic substance that accumulates in the central nervous system, where it may cause a neurological disorder...... that bears many similarities to Parkinson's disease. The aim of the study was to investigate the sources and levels of manganese exposure in foundry furnacemen by a combined measuring of blood-manganese (B-Mn) and manganese in ambient air (air-Mn)....

  17. Microstructural and mechanical investigation of aluminium alloy (Al 1050) melted by microwave hybrid heating

    Science.gov (United States)

    Shashank Lingappa, M.; Srinath, M. S.; Amarendra, H. J.

    2017-07-01

    Microwave processing of metals is an emerging area. Melting of bulk metallic materials through microwave irradiation is still immature. In view of this, the present paper discusses the melting of bulk Al 1050 metallic material through microwave irradiation. The melting process is carried out successfully in a domestic microwave oven with 900 W power at 2450 MHz frequency. Metallurgical and mechanical characterization of the processed and as-received material is carried out. Aluminium phase is found to be dominant in processed material when tested through x-ray diffraction (XRD). Microstructure study of as-cast metal through scanning electron microscopy (SEM) reveals the formation of uniform hexagonal grain structure free from pores and cavities. The average tensile strength of the cast material is found to be around 21% higher, when compared to as-received material. Vickers’ microhardness of the as-cast metal is measured and is 10% higher than that of the as-received metal. Radiography on as-cast metal shows no significant defects. Al 1050 material melted through microwave irradiation has exhibited superior properties than the as-received Al 1050.

  18. The effect of pre-straining and pre-ageing on a novel thermomechanical treatment for improving the mechanical properties of AA2139 aerospace aluminium alloys

    Science.gov (United States)

    Bakare, F.; Alsubhi, Y.; Ragkousis, A.; Ebomwonyi, O.; Damisa, J.; Okunzuwa, S.

    2017-07-01

    The novel thermomechanical treatment employed by Wang Z et al (2014 Mater. Sci. Eng. A 607 313-7) in enhancing the mechanical and microstructure properties of 6000 series aluminium alloys has been replicated for AA2139 aerospace aluminium alloys. The novel route which involves under-ageing, cold-rolling reductions and re-ageing at a fixed temperature has been carried out focusing on the effect of pre-straining and pre-ageing on the alloy properties. The influence of varying cold-rolling reductions and pre-ageing has been examined by tensile testing, hardness testing, differential scanning calorimetry, thermoelectric power measurements and scanning electron microscope (SEM). Further analyses were conducted with DSC and TEP measurements to check for precipitation sequence and solute retention respectively. On comparing the hardness and strength of the non pre-aged to the pre-aged samples, there is a remarkable increase in the hardness and strength of the aerospace alloy showing the huge influence of both pre-ageing and pre-straining stage of the novel thermomechanical treatment as observed in the 6000 series alloy, albeit at a higher rate. The treatments that exhibited the most promising mechanical properties (hardness, yield and ultimate tensile strength, elongation to failure) were found to be at a pre-ageing temperature of 175 °C for 1.5 h, 40% cold-rolling and re-ageing at 150 °C. The material was found to have yield strength of 590 MPa and 8.1% uniform elongation, which is well above the 5% acceptable value for structural applications and with strength levels adaptable for aerospace industries. The presence of higher volume fraction of well dispersed precipitates observed in the SEM further shows that intermediate cold-rolling reductions combines well with pre-ageing to give the best mechanical properties in this alloy.

  19. Hong Kong's Foundry Industry Survey

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    @@ Hong Kong, as one of the global economy centers, its manufacturing industry is well-known to the world. Foundry industry is named as "The Father of Manufacturing Industry",and in Hong Kong there currently are 1 500 enterprises, staffed with 500 000 employees. The following are some special features of the Hong Kong foundry industry.

  20. Foundry Coating Technology: A Review

    DEFF Research Database (Denmark)

    Nwaogu, Ugochukwu Chibuzoh; Tiedje, Niels Skat

    2011-01-01

    is important. In this review, a detailed description of these topics and examples are provided where necessary. A potential area of research in foundry coating development, using sol-gel process is suggested. The application of sol-gel technology in the development of foundry coatings is a novel approach....

  1. Perbedaan Kapasitas Vital Paksa Paru Tenaga Kerja pada Lokasi Pengecoran/ Pencetakan dan Lokasi Pengikiran/Pembubutan di Industri Kerajinan Cor Aluminium “ED” Giwangan Yogyakarta.

    OpenAIRE

    Ekawati Ekawati; Ari Suwondo

    2015-01-01

    ABSTRACT Background: Dust pollution can be exist at production process on industry, include on “ED” aluminium cast indust, Yogyakarta which is on the production process included foundry and fitting-shop process. Aluminium dust can influence lung function of the worker. The aim of this research was to study the difference of forced vital capacity (FVC) on workers between foundry and fitting-shop in “ED” aluminium cast industry, Giwangan Yogyakarta. Method: This was an observat...

  2. Microstructure and composition of rare earth-transition metal-aluminium-magnesium alloys

    Directory of Open Access Journals (Sweden)

    Lia Maria Carlotti Zarpelon

    2008-03-01

    Full Text Available The determination of the microstructure and chemical composition of La0.7-xPr xMg0.3Al 0.3Mn0.4Co0.5 Ni3.8 (0 < x < 0.7 metal hydride alloys has been carried out using scanning electron microscopy (SEM, energy dispersive X ray analysis (EDX and X ray diffraction analysis (XRD. The substitution of La with Pr changed the grain structure from equiaxial to columnar. The relative atomic ratio of rare earth to (Al, Mn, Co, Ni in the matrix phase was 1:5 (LaNi5-type structure. Magnesium was detected only in two other phases present. A grey phase revealed 11 at.% Mg and the concentration ratios of other elements indicated the composition to be close to PrMgNi4. A dark phase was very heterogeneous in composition, attributed to the as-cast state of these alloys. The phases identified by XRD analysis in the La0.7Mg0.3Al0.3Mn0.4Co 0.5Ni3.8 alloy were: La(Ni,Co5, LaAl(Ni,Co4, La2(Ni,Co7 and AlMn(Ni,Co2. Praseodymium favors the formation of a phase with a PuNi3-type structure. Cobalt substituted Ni in the structures and yielded phases of the type: Pr(Ni,Co5 and Pr(Ni,Co3.

  3. Observations on infiltration of silicon carbide compacts with an aluminium alloy

    Science.gov (United States)

    Asthana, R.; Rohatgi, P. K.

    1992-01-01

    The melt infiltration of ceramic particulates permits an opportunity to observe such fundamental materials phenomena as nucleation, dynamic wetting and growth in constrained environments. Experimental observations are presented on the infiltration behavior and matrix microstructures that form when porous compacts of platelet-shaped single crystals of alpha- (hexagonal) silicon carbide are infiltrated with a liquid 2014 Al alloy. The infiltration process involved counter gravity infiltration of suitably tamped and preheated compacts of silicon carbide platelets under an external pressure in a special pressure chamber for a set period, then by solidification of the infiltrant metal in the interstices of the bed at atmospheric pressure.

  4. [Comporison Sduty of Microstructure by Metallographicalk on the Polarized Light and Texture by XRD of CC 5083 and CC 5182 Aluminium Alloy after Cold Rolling and Recrystallization].

    Science.gov (United States)

    Chen, Ming-biao; Li, Yong-wei; Tan, Yuan-biao; Ma, Min; Wang, Xue-min; Liu, Wen-chang

    2015-03-01

    At present the study of relation between microstructure, texture and performance of CC 5083 aluminium alloy after cold tolling and recrystallization processes is still finitude. So that the use of the CC 5083 aluminium alloy be influenced. Be cased into electrical furnace, hot up with unlimited speed followed the furnace hot up to different temperature and annealed 2h respectively, and be cased into salt-beth furnace, hot up quickly to different temperature and annealed 30 min respectively for CC 5083 and CC 5182 aluminum alloy after cold roling with 91.5% reduction. The microstructure be watched use metallographic microscope, the texture be inspected by XRD. The start temperature of recrystallization and grain grow up temperature within annealing in the electric furnace of CC 5083 aluminum alloy board is 343 degrees C, and the shap of grain after grow up with long strip (the innovation point ); The start temperature of recrystallization within annealling in the salt bath furnace of CC 5083 is 343 degrees C. The start temperature and end temperature of recrystallization within annealling of CC 5083 and CC 5182 aluminum alloy is 371 degrees C. The grain grow up outstanding of cold rooled CC 5152 aluminum alloy after annealed with 454 degrees C in the electric furnace and salt bath furnace. The start temperature of grain grow up of CC 5083 alluminurn alloy annealed in the electric furnace and salt bath furnace respectively is higher than the start temperature of grain grow up of CC 5182 alluminum alloy annealed in the electric furnace and salt bath furnace respectively. The strat temperature of recrystallization grain grow up is higher than which annealled with other three manner annealing process. The recrystallization temperature of CC 5182 annealed in the salt bath furnace is higher than which annealed in the electric furnace. The recrystallization temperature of the surface layer of CC 5083 and CC 5182 aluminum alloy is higher than the inner layer (the innovation

  5. Effect of tool pin profile on microstructure and tensile properties of friction stir welded dissimilar AA 6061–AA 5086 aluminium alloy joints

    Directory of Open Access Journals (Sweden)

    M. Ilangovan

    2015-06-01

    Full Text Available Joints between two different grades of aluminium alloys are need of the hour in many light weight military structures. In this investigation, an attempt has been made to join the heat treatable (AA 6061 and non-heat treatable (AA 5086 aluminium alloys by friction stir welding (FSW process using three different tool pin profiles like straight cylindrical, taper cylindrical and threaded cylindrical. The microstructures of various regions were observed and analyzed by means of optical and scanning electron microscope. The tensile properties and microhardness were evaluated for the welded joint. From this investigation it is founded that the use of threaded pin profile of tool contributes to better flow of materials between two alloys and the generation of defect free stir zone. It also resulted in higher hardness values of 83 HV in the stir zone and higher tensile strength of 169 MPa compared to other two profiles. The increase in hardness is attributed to the formation of fine grains and intermetallics in the stir zone, and in addition, the reduced size of weaker regions, such as TMAZ and HAZ regions, results in higher tensile properties.

  6. Corrosion of aluminium, stainless steels and AISI 680 nickel alloy in nitrogen-based fuels

    Energy Technology Data Exchange (ETDEWEB)

    Kap, I.; Starostin, M.; Shter, G.E.; Grader, G.S. [Department of Chemical Engineering, Technion-Israel Institute of Technology, Haifa (Israel)

    2012-07-15

    Nitrogen-based compounds can potentially be used as alternative non-carbon or low-carbon fuels. Nevertheless, the corrosion of construction materials at high temperatures and pressures in the presence of such fuel has not been reported yet. This work is focused on the corrosion of AISI Al 6061, 1005 carbon steel (CS), 304, 316L, 310 austenitic stainless steels (SS) and 680 nickel alloy in highly concentrated water solution of ammonium nitrate and urea (ANU). The corrosion at 50 C and ambient pressure and at 350 C and 20 bar was investigated to simulate storage and working conditions. Sodium chloride was added to the fuel (0-5 wt%) to simulate industrial fertilizers and accelerated corrosion environment. Heavy corrosion of CS was observed in ANU solution at 50 C, while Al 6061, 304 and 316L SS showed high resistance both to uniform and pitting corrosion in ANU containing 1% of sodium chloride. Addition of 5% sodium chloride caused pitting of Al 6061 but had no influence on the corrosion of SS. Tests in ANU at 350 C and 20 bar showed pitting on SS 304 and 316L and 680 nickel alloy. The highest corrosion resistance was found for SS 310 due to formation of stable oxide film on its surface. (Copyright copyright 2012 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)

  7. Corrosion behavior of Cu-Ni-Ag-Al alloy anodes in aluminium electrolysis

    Institute of Scientific and Technical Information of China (English)

    徐君莉; 石忠宁; 邱竹贤

    2004-01-01

    The behavior of Cu-Ni-Ag-Al alloy used as anode for aluminum electrolysis was directly visualized in a two-compartment see-through cell during electrolysis, and its performances were tested at 850℃ in acidic electrolyte molten salts consisting of 39.3 % NaF-43.7 % AlF3-8 % NaCl-5 % CAF2-4 % Al2 O3 for 40 h in a laboratory cell. The results show that nascent oxygen oxidizes the anodic surface to form oxide film at the beginning of electrolysis. X-ray diffraction analysis of alloy surface show that the oxide film on the anodic surface consists of CuO, NiO, Al2O3,CuAl2 O4 and NiAl2 O4. However, SEM image shows the oxide film is porous, loose and easy to fall into electrolyte and to contaminate aluminum. The corrosion mechanism of metal anodes was analyzed.

  8. Phase composition, microstructure and microhardness of electroless nickel composite coating co-deposited with SiC on cast aluminium LM24 alloy substrate

    OpenAIRE

    2013-01-01

    Electroless Ni–P (EN) and composite Ni–P–SiC (ENC) coatings were developed on cast aluminium alloy substrate, LM24. The coating phase composition, microstructure and microhardness were investigated using X-ray diffraction (XRD), scanning electron microscopy (SEM) and microhardness tester, respectively, on as-plated and heat-treated specimens. The original microstructure of the Ni–P matrix is not affected by the inclusion of the hard particles SiC. No formation of Ni–Si phase was observed up t...

  9. Characterisation of phase composition, microstructure and microhardness of electroless nickel composite coating co-deposited with SiC on casting aluminium LM24 alloy substrate

    OpenAIRE

    2013-01-01

    Electroless Ni-P (EN) and composite Ni-P-SiC (ENC) coatings were developed on cast aluminium alloy, LM24. The coating phase composition, microstructure and microhardness were investigated using X-ray diffraction (XRD), scanning electron microscopy (SEM) and microhardness tester, respectively, on as-plated and heat-treated specimens. The original microstructure of the Ni-P matrix is not affected by the inclusion of the hard particles SiC. No formation of Ni-Si phase was observed upto 500°C of ...

  10. Effect of welding techniques on microstructure and mechanical properties of aluminium-lithium alloy welds

    Energy Technology Data Exchange (ETDEWEB)

    Madhusudhan Reddy, G.; Gokhale, A.A.; Saxena, V.K. [Defence Metallurgical Research Lab., Hyderabad (India); Prasad Rao, K.

    2000-07-01

    The tensile properties and fatigue crack growth behaviour of sheets of an Al-1.9Li-1.8Cu-1.0 Mg-0.1Zr alloy welded under different conditions were evaluated. The basic welding technique was constant current (CC) gas tungsten arc (GTA) welding. Two modifications viz. pulsed current (PC) and magnetic arc oscillation (AO) were introduced to study effects on microstructure and properties. Both PC and AO resulted in microstructural refinement in the fusion zone. The tensile residual stresses present in CC welds reduced when either PC or AO welding was used. The tensile strength and ductility increased, and fatigue crack growth rates lowered when PC or AO conditions replaced CC welding. (orig.)

  11. Effect of hydrogen charging on the mechanical properties of medium strength aluminium alloys 2091 and 2014

    DEFF Research Database (Denmark)

    Bandopadhyay, A.; Ambat, Rajan; Dwarakadasa, E.S.

    1992-01-01

    Cathodic hydrogen charging in 3.5% NaCl solution altered the mechanical properties of 2091-T351 (Al-Cu-Li-Mg-Zr) determined by a slow (10(-3)/s) strain rate tensile testing technique. UTS and YS decreased in the caw of 2091-T351 and 2014-T6(Al-Cu-Mn-Si-Mg) with increase in charging current density....... Elongation showed a decrease with increase in charging current density for both the alloys. However, elongation occurring throughout the gauge length in uncharged specimens changed over to localized deformation, thus increasing the reduction in area in charged specimens. A transition in fracture mode from...... surface (brittle) to the core (ductile) was observed. The presence of hydrogen increased the hardness, mostly indicative of solution strengthening and it decreased with depth confirming the existence of hydrogen concentration gradient. The effects were similar in 2014-T6, but to a slightly smaller extent....

  12. On the melt infiltration of copper coated silicon carbide with an aluminium alloy

    Science.gov (United States)

    Asthana, R.; Rohatgi, P. K.

    1992-01-01

    Pressure-assisted infiltration of porous compacts of Cu coated and uncoated single crystals of platelet shaped alpha (hexagonal) SiC was used to study infiltration dynamics and particulate wettability with a 2014 Al alloy. The infiltration lengths were measured for a range of experimental variables which included infiltration pressure, infiltration time, and SiC size. A threshold pressure (P(th)) for flow initiation through compacts was identified from an analysis of infiltration data; P(th) decreased while penetration lengths increased with increasing SiC size (more fundamentally, due to changes in interparticle pore size) and with increasing infiltration times. Cu coated SiC led to lower P(th) and 60-80 percent larger penetration lengths compared to uncoated SiC under identical processing conditions.

  13. Effect of partition coefficient on microsegregation during solidification of aluminium alloys

    Institute of Scientific and Technical Information of China (English)

    MH Avazkonandeh-Gharavol; M Haddad-Sabzevar; H Fredriksson

    2014-01-01

    In the modeling of microsegregation, the partition coefficient is usually calculated using data from the equilibrium phase diagrams. The aim of this study was to experimentally and theoretically analyze the partition coefficient in binary aluminum-copper alloys. The sam-ples were analyzed by differential thermal analysis (DTA), which were melted and quenched from different temperatures during solidifica-tion. The mass fraction and composition of phases were measured by image processing and scanning electron microscopy (SEM) equipped with an energy-dispersive X-ray spectroscopy (EDS) unit. These data were used to calculate as the experimental partition coefficients with four different methods. The experimental and equilibrium partition coefficients were used to model the concentration profile in the primary phase. The modeling results show that the profiles calculated by the experimental partition coefficients are more consistent with the experi-mental profiles, compared to those calculated using the equilibrium partition coefficients.

  14. Porosity evolution in additively manufactured aluminium alloy during high temperature exposure

    Science.gov (United States)

    Bai, J.; Ding, H. L.; Gu, J. L.; Wang, X. S.; Qiu, H.

    2017-01-01

    A 2319 aluminum alloy is deposited by the Wire+Arc Additive Manufacturing technology with Cold Metal Transfer process. Porosity that are both existing in the as-deposited and as-heat treated state metal are revealed by optical microscopy and quantitatively analyzed. It explains the reason why the newly initiated pores are easily tend to gather between each layer around the fusion line zone for the WAAM metal after heat treatment. The inner morphology of the pores are demonstrated by Scanning Electron Microscopy. Porosity evolution and distribution during high temperature exposure are demonstrated. Thus two porosity growth and number increase mechanisms are proposed eventually, providing theoretical basis for related material design and process optimization.

  15. Effects of welding parameters on the mechanical properties of inert gas welded 6063 Aluminium alloys

    Energy Technology Data Exchange (ETDEWEB)

    Ertan, Taner [MAKO Corporation (Turkey); Uguz, Agah [Uludag Univ. (Turkey). Mechnical Engineering Dept.; Ertan, Rukiye

    2012-07-01

    The influence of welding parameters, namely welding current and gas flow rate, on the mechanical properties of Gas Tungsten Arc Welding (GTAW) and Shielded Metal Arc Welding (SMAW) welded 6063 Aluminum alloy (AA 6063) has been investigated. In order to study the effect of the welding current and gas flow rate, microstructural examination, hardness measurements and room temperature tensile tests have been carried out. The experimental results show that the mechanical properties of GTAW welded joints have better mechanical properties than those of SMAW welded joints. Increasing the welding current appeared to have a beneficial effect on the mechanical properties. However, either increasing or decreasing the gas flow rate resulted in a decrease of hardness and tensile strength. It was also found that, the highest strength was obtained in GTAW welded samples at 220 A and 15 l/min gas flow rate.

  16. Spectroscopic study of plasma during electrolytic oxidation of magnesium- and aluminium-alloy

    Science.gov (United States)

    Jovović, J.; Stojadinović, S.; Šišović, N. M.; Konjević, N.

    2012-10-01

    We present the results of an optical emission spectroscopy study of Plasma during Electrolytic Oxidation (PEO) of magnesium- and aluminum-alloy. Plasma electron number density Ne diagnostics is performed either from the Hβ line shape or from the width or shift of non-hydrogenic ion lines of aluminum and magnesium. The line profile analysis of the Hβ suggests presence of two PEO processes characterized by relatively low electron number densities Ne≈1.2×1015 cm-3 and Ne≈2.3×1016 cm-3. Apart from these two low Ne processes, there is the third one related to the ejection of evaporated anode material through micro-discharge channels. This process is characterized by larger electron density Ne=(1.2-1.6)1017 cm-3, which is detected from the shape and shift of aluminum and magnesium singly charged ion lines. Two low Ne values detected from the Hβ and large Ne measured from the widths and shift of ion lines suggest presence of three types of discharges during PEO with aluminum- and magnesium-alloy anode. On the basis of present and earlier results one can conclude that low Ne processes do not depend upon anode material or electrolyte composition.The electron temperature of 4000 K and 33,000 K are determined from relative intensities of Mg I and O II lines, respectively. The attention is drawn to the possibility of Ne application for Te evaluation using Saha equation what is of importance for PEO metal plasma characterization. During the course of this study, difficulties in the analysis of spectral line shapes are encountered and the ways to overcome some of the obstacles are demonstrated.

  17. The effects of nickel-pigmented aluminium oxide selective coating over aluminium alloy on the optical properties and thermal efficiency of the selective absorber prepared by alternate and reverse periodic plating technique

    Energy Technology Data Exchange (ETDEWEB)

    Wazwaz, A. [Chemical Engineering Department, College of Engineering, Dhofar University, P.O. Box 2509, Postal Code 211, Salalah (Oman); Salmi, J. [Marion Technologies Nanomaterials, Nanostructured Materials and Ceramic Powders, Cap Delta - Parc Technologique, Delta Sud, F-09340 Verniolle (France); Bes, R. [CIRIMAT/LCMIE, Universite Paul Sabatier, 31062 Toulouse Cedex 4 (France)

    2010-08-15

    Diffused reflectance measurements and Kubelka-Munk values were studied. The effects of the alumina layer and the nickel content on the optical properties of the selective absorber were discussed. In general and with respect to aluminium alloy substrate, the diffused reflectance decreased by 85.25-91.42% ({+-}0.01%). The emissivity increased by a factor of 252.50-624.50 ({+-}0.01). The average absorptivity increased by a factor of 4.99-5.35 ({+-}0.01). The average thermal efficiency is increased by a factor of 4.51-4.80 ({+-}0.01). The sample of nickel content 60 {mu}g/cm{sup 2} was found to have the optimum optical properties as a good selective absorber. It has the highest solar selectivity by the two measurements. The range of hemispherical solar selectivity is 4.22-8.36 ({+-}0.01); while for average solar selectivity is 7.410-17.456 ({+-}0.001). We found that the thermal efficiency is increased by increasing the nickel content to a certain limit (60 {mu}g/cm{sup 2}) then it decreased after this limit due to the increase in the emissivity. Also, the total hemispherical optical properties are accordance with the averaged optical properties obtained from diffused reflectance measurements over the solar range. The nickel-pigmented aluminium oxide is one of the best selective absorbers for the photo thermal conversion and it is of high durability. (author)

  18. Behaviour and fatigue damage study of cast aluminium alloys; Etude du comportement et de l'endommagement en fatigue d'alliages d'aluminium de fonderie

    Energy Technology Data Exchange (ETDEWEB)

    Barlas, B.

    2004-02-15

    This study is aimed at determining the influence of chemical composition and heat treatment of cast aluminium alloys Al-Si-Cu-Mg on mechanical behaviour and fatigue life of structures. The industrial frame of this study concerns cylinder-heads of high efficiency diesel engines, for Renault and Montupet companies. The experimental means involved in this work are as well microscopic (TEM, microhardness, image analysis), mechanical (LCF and aniso-thermal tests, macro-hardness) and numerical (simulation of the stability of the hardening phases, behaviour and damage model identification, cylinder-head life time calculation). The link between micro and macro approaches is provided by the means of an internal microscopic variable representing thermal aging through coarsening of the precipitates and implemented into the macroscopic model. (author)

  19. The effect of welding parameters on surface quality of AA6351 aluminium alloy

    Science.gov (United States)

    Yacob, S.; MAli, M. A.; Ahsan, Q.; Ariffin, N.; Ali, R.; Arshad, A.; Wahab, M. I. A.; Ismail, S. A.; Roji, NS M.; Din, W. B. W.; Zakaria, M. H.; Abdullah, A.; Yusof, M. I.; Kamarulzaman, K. Z.; Mahyuddin, A.; Hamzah, M. N.; Roslan, R.

    2015-12-01

    In the present work, the effects of gas metal arc welding-cold metal transfer (GMAW-CMT) parameters on surface roughness are experimentally assessed. The purpose of this study is to develop a better understanding of the effects of welding speed, material thickness and contact tip to work distance on the surface roughness. Experiments are conducted using single pass gas metal arc welding-cold metal transfer (GMAW-CMT) welding technique to join the material. The material used in this experiment was AA6351 aluminum alloy with the thickness of 5mm and 6mm. A Mahr Marsuft XR 20 machine was used to measure the average roughness (Ra) of AA6351 joints. The main and interaction effect analysis was carried out to identify process parameters that affect the surface roughness. The results show that all the input process parameters affect the surface roughness of AA6351 joints. Additionally, the average roughness (Ra) results also show a decreasing trend with increased of welding speed. It is proven that gas metal arc welding-cold metal transfer (GMAW-CMT)welding process has been successful in term of providing weld joint of good surface quality for AA6351 based on the low value surface roughness condition obtained in this setup. The outcome of this experimental shall be valuable for future fabrication process in order to obtained high good quality weld.

  20. Investigation of Corrosion Behaviour of Aluminium Alloy Subjected to Laser Shock Peening without a Protective Coating

    Directory of Open Access Journals (Sweden)

    U. Trdan

    2015-01-01

    Full Text Available The effect of shock waves and strain hardening of laser shock peening without protective coating (LSPwC on alloy AA 6082-T651 was investigated. Analysis of residual stresses confirmed high compression in the near surface layer due to the ultrahigh plastic strains and strain rates induced by multiple laser shock waves. Corrosion tests in a chloride environment were carried out to determine resistance to localised attack, which was also verified on SEM/EDS. OCP transients confirmed an improved condition, that is, a more positive and stable potential after LSPwC treatment. Moreover, polarisation resistance of the LSPwC treated specimen was by a factor of 25 higher compared to the untreated specimen. Analysis of voltammograms confirmed an improved enhanced region of passivity and significantly smaller anodic current density of the LSPwC specimen compared to the untreated one. Through SEM, reduction of pitting attack at the LSPwC specimen surface was confirmed, despite its increased roughness.

  1. Market Opportunity of Some Aluminium Silicon Alloys Materials through Changing the Casting Process

    Directory of Open Access Journals (Sweden)

    Delfim SOARES

    2012-08-01

    Full Text Available Fatigue is considered to be the most common mechanism by which engineering components fail, and it accounts for at least 90% of all service failures attributed to mechanical causes. Mechanical properties (tensile strength, tensile strain, Young modulus, etc as well as fatigue properties (fatigue life are very dependent on casting method. The most direct effects of casting techniques are on the metallurgical microstructure that bounds the mechanical properties. One of the important variables affected by the casting technique is the cooling rate which is well known to strongly restrict the microstructure. In the present research has been done a comparison of fatigue properties of two aluminum silicon alloys obtained by two casting techniques. It was observed that the fatigue life is increasing with 24% for Al12Si and 31% for AL18Si by using centrifugal casting process instead of gravity casting. This increasing in fatigue life means that a component tailored from materials obtained by centrifugal casting will stay longer in service. It was made an estimation of the time required to recover the costs of technology in order to use the centrifuge process that will allow to obtain materials with improved properties. The amortization can be achieved by using two different marketing techniques: through the release of the product at the old price and with much longer life of the component which means "same price - longer life", or increasing price, by highlighting new product performance which means "higher price - higher properties".

  2. Study of process parameters on aluminium foam formation in the Al-6Si-3Mg alloy

    Directory of Open Access Journals (Sweden)

    J. Juarez-Hernandez

    2014-04-01

    Full Text Available The aim of this research was to study the process parameters that promote foam formation by injecting N2 into Al-6Si-3Mg wt % molten alloy with silicon carbide particles additions (SiC. An experimental design was proposed, in which the contents of SiC particles were 0, 10, 30 and 50 wt %, and the overheating was defined as ΔT= TF - TL , where TL is the liquidus temperature and was determined by the cooling curve method and the foaming temperatures were selected as TF at 630, 610, 580 and 570 °C. Flow and pressure of air blow were constant, 2,0 lt/min and 4,0 atm, respectively. The foam formation was possible only under two experimental conditions, 10 wt % SiC at ΔT > 12 °C and 30 wt % SiC at ΔT > 10 °C. The foams obtained under these conditions were stable, while with other conditions of experiments, bubble coallesence occurred. Finally, it was concluded that the foam formation occurred by SiC contents lower than 30 wt % SiC and temperatures slightly above the liquidus.

  3. Propagation mode of Portevin-Le Chatelier plastic instabilities in an aluminium-magnesium alloy

    Energy Technology Data Exchange (ETDEWEB)

    Zeghloul, A.; Mliha-Touati, M.; Bakir, S. [Univ. de Metz (France). Lab. de Physique et Mecanique des Materiaux

    1996-11-01

    The Portevin-Le Chatelier (PLC) effect is characterized by the appearance of serrations in load (hard tensile machine for constant strain rate tests) or by steps (soft tensile machine for constant stress rate tests) or by steps (soft tensile machine for constant stress rate tests) on the stress-strain curves. It is now widely accepted that the PLC propagative instability stems from the dynamic interaction between diffusing solute atoms and mobile dislocations in the temperature and strain rate ranges where dynamic strain ageing (DSA) takes place. This competition results in a negative strain-rate sensitivity. However, in some alloys, like concentrated solid solutions, shearing of precipitates accompanied by their dissolution and subsequent reprecipitation during tensile test may also lead to a negative strain rate sensitivity. In view of the renewed theoretical interest in propagative instabilities, it is important that the experimental features of band propagation be well characterized. In this work the authors present experimental results that are obtained from the investigation of the PLC bands associated with discontinuous yielding. These results show that the band strain, the band velocity and the propagation mode of the bands depend on the stress rate when the test is carried out on a soft tensile machine.

  4. Investigation of surface finishing of carbon based coated tools for dry deep drawing of aluminium alloys

    Science.gov (United States)

    Steiner, J.; Andreas, K.; Merklein, M.

    2016-11-01

    Global trends like growing environmental awareness and demand for resource efficiency motivate an abandonment of lubricants in metal forming. However, dry forming evokes increased friction and wear. Especially, dry deep drawing of aluminum alloys leads to intensive interaction between tool and workpiece due to its high adhesion tendency. One approach to improve the tribological behavior is the application of carbon based coatings. These coatings are characterized by high wear resistance. In order to investigate the potential of carbon based coatings for dry deep drawing, friction and wear behavior of different coating compositions are evaluated in strip drawing tests. This setup is used to model the tribological conditions in the flange area of deep drawing operations. The tribological behavior of tetrahedral amorphous (ta-C) and hydrogenated amorphous carbon coatings with and without tungsten modification (a-C:H:W, a-C:H) is investigated. The influence of tool topography is analyzed by applying different surface finishing. The results show reduced friction with decreased roughness for coated tools. Besides tool topography the coating type determines the tribological conditions. Smooth tools with ta-C and a-C:H coatings reveal low friction and prevent adhesive wear. In contrast, smooth a-C:H:W coated tools only lead to slight improvement compared to rough, uncoated specimen.

  5. Friction Stir Welds (FSW of aluminium alloy AW6082-T6

    Directory of Open Access Journals (Sweden)

    J. Adamowski

    2007-01-01

    Full Text Available Purpose: Purpose of this paper is the investigation on the properties and microstructural changes in Friction StirWelds in the aluminum alloy 6082-T6 in function of varying process parameters.Design/methodology/approach: Tensile strength of the produced joints was tested and the correlation withprocess parameter was assessed. Microstructures of various zones of FSW welds are presented and analyzed bymeans of optical microscopy and microhardness measurements.Findings: Mechanical resistance of test welds increased with the increase of travel (welding speed withconstant rotational speed. Softening of the material in weld nugget and heat affected zone was observed, ofentity inferior that that of fusion welds. Origin of tunnel (worm hole defects were found and analyzed.Research limitations/implications: The test welds were produced with various combinations of processparameters without the possibility of controlling the downward force. Further extension of applicable parameterscombinations could be examined.Practical implications: The increase of mechanical resistance with increasing welding speed offers animmediate economic return, as the process efficiency is increased.Originality/value: Information contained herein can be useful to further investigate on the possibility ofimproving the properties of FSW welds, as well as the efficiency of the process.

  6. Pengaruh Variasi Komposisi Serbuk Kayu Dengan Pengikat Semen Pada Pasir Cetak Terhadap Cacat Porositas Dan Kekasaran Permukaan Hasil Pengecoran Aluminium Alloy 6061

    Directory of Open Access Journals (Sweden)

    Fatkhur M Rohman

    2014-09-01

    Full Text Available Proses pengecoran dilakukan dengan cara mencairkan logam dalam dapur pelebur, kemudian dituangkan ke dalam cetakan dan dibiarkan membeku hingga dapat dikeluarkan dari dalam cetakan. Faktor yang berpengaruh terhadap kualitas hasil pengecoran cetakan pasir, diantaranya adalah komposisi cetakan pasir dan perancangan sistem saluran (gatting system. Pada penelitian ini bertujuan untuk menganalisa pengaruh variasi komposisi serbuk kayu dengan pengikat semen pada pasir cetak terhadap cacat porositas dan kekasaran permukaan hasil pengecoran aluminium alloy 6061. Bahan yang digunakan pada penelitian ini adalah aluminium Alloy 6061 dan komposisi semen dan air sebesar 6%, komposisi serbuk kayu sebesar 1%, 2%, 3%, 4%, 5% dan 6%  komposisi pasir silika sebesar 87%, 86%, 85%, 84%, 83% dan 82%. Dari hasil penelitian ini didapatkan nilai uji permeabilitas pasir cetak cenderung bertambah seiring dengan bertambahnya serbuk kayu. Nilai uji kompresi pasir cetak cenderung berkurang seiring dengan bertambahnya serbuk kayu.. Nilai pengujian porositas benda hasil coran didapatkan nilai terkecil terletak pada komposisi serbuk kayu 6% dan nilainya sebesar 0,25%, sedangkan nilai pengujian porositas benda hasil coran terbesar terletak pada komposisi serbuk kayu 1% dengan nilai sebesar 4,96%. Nilai pengujian kekasaran permukaan benda hasil coran didapatkan nilai terkecil terletak pada komposisi serbuk kayu 6% dan nilainya sebesar 0,06µm, sedangkan nilai pengujian kekasaran permukaan benda hasil coran terbesar terletak pada komposisi serbuk kayu 1% dengan nilai sebesar 2,00µm.

  7. Effect of Welding Speed and Tool Pin Geometry on Impact Strength in Friction Stir Welding of Aluminium 6101 T6 Alloy

    Directory of Open Access Journals (Sweden)

    Singh Rajbir

    2016-01-01

    Full Text Available Friction stir welding (FSW process is a solid state joining method in which the material that is being welded does not melt and recast. This process uses a non-consumable tool to generate frictional heat in the abutting surfaces. The welding parameters play a major role in deciding the joint characteristics. In this investigation the effect of welding speed and tool pin geometry in friction stir welds of Aluminium alloy was studied. The welded joints were made of Aluminium alloy AA 6101 T6 strips of 6mm thickness with different tool pin profile (Cylindrical, Taper cylindrical, Square and Taper Square. All the welding operations were done at the room temperature. Charpy tests were carried out to find the impact strength. From this investigation it is found that strength is superior with taper square tool pin profile than cylindrical, taper cylindrical and square tool pin profile. The pieces weld at rotational speed of 1200 r.p.m and welding speed of 70mm/min using taper square tool have higher strength.

  8. Dilatometric Characterization of Foundry Sands

    Directory of Open Access Journals (Sweden)

    M. Břuska

    2012-04-01

    Full Text Available The goal of this contribution is summary of physical – chemistry properties of usually used foundry silica and no – silica sands in Czech foundries. With the help of dilatometry analysis theoretical assumptions of influence of grain shape and size on dilatation value of sands were confirmed. Determined was the possibility of dilatometry analysis employment for preparing special (hybrid sands with lower and/or more linear character of dilatation.

  9. The Influence of Ni and V Trace Elements on High-Temperature Tensile Properties and Aging of A356 Aluminum Foundry Alloy

    Science.gov (United States)

    di Giovanni, Maria Teresa; Cerri, Emanuela; Casari, Daniele; Merlin, Mattia; Arnberg, Lars; Garagnani, Gian Luca

    2016-05-01

    High-temperature tensile properties of unmodified A356 alloy with and without the addition of Ni or V in traces (600 and 1000 ppm of Ni and V, respectively) were investigated by analyzing samples obtained from sand and permanent mold castings in the as-cast and T6 heat-treated conditions. Tensile tests were performed at 508 K (235 °C) at a crosshead speed of 1 mm/min. In addition, samples were subjected to artificial aging at 508 K (235 °C) for different times, and corresponding hardness curves were plotted. Microstructures and fracture surfaces, analyzed by FEG-SEM equipped with energy dispersive X-ray spectroscopy, showed that neither Ni nor V addition had a detrimental effect on high-temperature tensile properties. Aging curves showed a strong loss of hardness affecting the T6 class between 30-min and 1-h exposure time. After 6-h aging, no evidence of aging treatment persisted on hardness of the tested material. Hardness values did not reveal any significant difference between the reference alloy and the Ni- and V-containing alloys in both casting conditions, in complete analogy with the tensile properties. Unmodified eutectic silicon particles provided inhomogeneity in the α-Al matrix and acted as the principal source of stress concentration leading to fracture.

  10. Semiconductor foundry, lithography, and partners

    Science.gov (United States)

    Lin, Burn J.

    2002-07-01

    The semiconductor foundry took off in 1990 with an annual capacity of less than 0.1M 8-inch-equivalent wafers at the 2-mm node. In 2000, the annual capacity rose to more than 10M. Initially, the technology practiced at foundries was 1 to 2 generations behind that at integrated device manufacturers (IDMs). Presently, the progress in 0.13-mm manufacturing goes hand-in-hand with any of the IDMs. There is a two-order of magnitude rise in output and the progress of technology development outpaces IDMs. What are the reasons of the success? Is it possible to sustain the pace? This paper shows the quick rise of foundries in capacity, sales, and market share. It discusses the their uniqueness which gives rise to advantages in conjunction with challenges. It also shows the role foundries take with their customer partners and supplier partners, their mutual dependencies, as well as expectations. What role then does lithography play in the foundries? What are the lithographic challenges to sustain the pace of technology? The experience of technology development and transfer, at one of the major foundries, is used to illustrate the difficulties and progresses made. Looking into the future, as semiconductor manufacturing will become even more expensive and capital investment more prohibitive, we will make an attempt to suggest possible solutions.

  11. Crack avoidance during powder metallurgy of a SiC particle reinforced aluminium alloy A 6063; Rissvermeidung bei der schmelzmetallurgischen Herstellung einer SiC-partikelverstaerkten Aluminiumlegierung A6063

    Energy Technology Data Exchange (ETDEWEB)

    Karaaslan, A. [Technische Univ. Yildiz (Turkey). Sektion Werkstofftechnik; Lus, M. [Technische Univ. Yildiz (Turkey). Sektion Werkstoff- und Gusstechnik

    2007-07-01

    Light alloys compounds are gaining increasing importance as compared to non-reinforced matrix materials. The present contribution highlights the powder metallurgical fabrication of a aluminium alloy reinforced with silicon carbide. Quite good results were achieved by addition of 12 volume percent silicon carbide. In the scope of the investigations also the cast and forming temperatures were optimized to achieve an optimum distribution of the silicon carbide during production of the compounds. (orig.)

  12. 铝热法制备高钒铝合金的研究%Study on high grade vanadium-aluminium alloy prepared by aluminothermic reaction

    Institute of Scientific and Technical Information of China (English)

    喇培清; 卢学峰; 申达; 魏玉鹏; 王鸿鼎; 郭鑫

    2012-01-01

    用V2O5粉和Al粉为原料,通过铝热还原法制备了高钒铝合金,研究了反应物配比中Al含量对制备的高钒铝合金纯度和钒回收率的影响.结果表明:当反应物配比中Al欠量5%时,高钒铝合金的纯度最高为98.45%;随着反应物配比中Al含量的增加,高钒铝合金的纯度降低,钒的回收率增加,在Al过量15%时回收率最高为92.4%(质量分数).高钒铝合金的布氏硬度在Al欠量5%时最低,为213.6 HB;在Al过量15%时布氏硬度最大,为250 HB.可以通过调节原料中Al含量来制备不同纯度的高钒铝合金.%High grade vanadium - aluminium alloy was prepared by aluminothermic reaction using V2O5 and Al powders as raw materials. The effects of Al content in raw materials on purity of alloy and recovery of vanadium were investigated in this study. The results show that the purity of vanadium decreases with the addition of aluminum element in raw materials and there exists a maximum value of 98. 45% when aluminum element is 5% shortfall in raw materials. The recovery rate of vanadium increases with increasing aluminum element in raw materials and there exists a maximum value of 92. 4% when aluminum element is 15% excess in raw materials. Brinell hardness of alloy comes to the minimum value of 213. 6 HB when aluminum element is 5% shortfall, and comes to the maximum value of 250 HB when aluminum element is 15% excess. The high grade vanadium - aluminium alloy with different purities can be prepared by varying the content of aluminium in raw materials.

  13. Design and operation of an aluminium alloy tank using doped Na3AlH6 in kg scale for hydrogen storage

    Science.gov (United States)

    Urbanczyk, R.; Peinecke, K.; Meggouh, M.; Minne, P.; Peil, S.; Bathen, D.; Felderhoff, M.

    2016-08-01

    In this publication the authors present an aluminium alloy tank for hydrogen storage using 1921 g of Na3AlH6 doped with 4 mol% of TiCl3 and 8 mol% of activated carbon. The tank and the heat exchangers are manufactured by extrusion moulding of Al-Mg-Si based alloys. EN AW 6082 T6 alloy is used for the tank and a specifically developed alloy with a composition similar to EN AW 6060 T6 is used for the heat exchangers. The three heat exchangers have a corrugated profile to enhance the surface area for heat transfer. The doped complex hydride Na3AlH6 is densified to a powder density of 0.62 g cm-3. The hydrogenation experiments are carried out at 2.5 MPa. During one of the dehydrogenation experiments approximately 38 g of hydrogen is released, accounting for gravimetric hydrogen density of 2.0 mass-%. With this tank 15 hydrogenation and 16 dehydrogenation tests are carried out.

  14. Mn对6061合金组织和硬度的影响%The effects of Mn addition on microstructure and hardness in 6061 aluminium alloy

    Institute of Scientific and Technical Information of China (English)

    文忠; 建塬; 王彬; 曾建民

    2013-01-01

    The effects of Mn addition on the microstructure and hardness of 6061 aluminum alloy were studied by means of scanning electron microscope (SEM) , energy dispersive X-Ray analysis (EDX), X-ray diffraction (XRD) and hardness tester in this work. The results show that rod and fishbone AlSiFeMn phase will be formed in the alloy with Mn addition in 6061 aluminium alloy, by the mean of XRD, the Mn12Si7Al5 phase is found in the 6061 aluminium alloy with 0.7%Mn. The hardness increases with the increasing of Mn contents both for as-cast and for T6 heat treatment. However, the hardness growth rate for as-cast is much more than that for T6 heat treatment at the same Mn addition in the 6061 alloy. Mn has a little effect on the hardness for T6 heat treatment in 6061 alloy.%通过扫描电镜/能谱仪、X射线衍射仪以及硬度计,研究了在6061合金中添加少量的 Mn,对6061合金的微观组织和硬度的影响。研究表明:在6061合金中添加微量的Mn,合金的微观组织中出现白色的鱼骨状和条块状的AlSiFeMn结晶相。在对含Mn量为0.7%的6061合金进行XRD分析时发现有Mn12Si7Al5相的衍射峰。对比6061合金的铸态硬度和时效硬度随Mn含量的变化趋势,发现添加微量的Mn对合金的铸态硬度的提高较明显,而对合金的时效硬度的提高所起的所用较小。

  15. In situ monitoring of corrosion mechanisms and phosphate inhibitor surface deposition during corrosion of zinc-magnesium-aluminium (ZMA) alloys using novel time-lapse microscopy.

    Science.gov (United States)

    Sullivan, James; Cooze, Nathan; Gallagher, Callum; Lewis, Tom; Prosek, Tomas; Thierry, Dominique

    2015-01-01

    In situ time-lapse optical microscopy was used to examine the microstructural corrosion mechanisms in three zinc-magnesium-aluminium (ZMA) alloy coated steels immersed in 1% NaCl pH 7. Preferential corrosion of MgZn(2) lamellae within the eutectic phases was observed in all the ZMA alloys followed by subsequent dissolution of Zn rich phases. The total extent and rate of corrosion, measured using time-lapse image analysis and scanning vibrating electrode technique (SVET) estimated mass loss, decreased as Mg and Al alloying additions were increased up to a level of 3 wt% Mg and 3.7 wt% Al. This was probably due to the increased presence of MgO and Al(2)O(3) at the alloy surface retarding the kinetics of cathodic oxygen reduction. The addition of 1 × 10(-2) mol dm(-3) Na(3)PO(4) to 1% NaCl pH 7 had a dramatic influence on the corrosion mechanism for a ZMA with passivation of anodic sites through phosphate precipitation observed using time-lapse image analysis. Intriguing rapid precipitation of filamentous phosphate was also observed and it is postulated that these filaments nucleate and grow due to super saturation effects. Polarisation experiments showed that the addition of 1 × 10(-2) mol dm(-3) Na(3)PO(4) to the 1% NaCl electrolyte promoted an anodic shift of 50 mV in open circuit potential for the ZMA alloy with a reduction in anodic current of 2.5 orders of magnitude suggesting that it was acting primarily as an anodic inhibitor supporting the inferences from the time-lapse investigations. These phosphate additions resulted in a 98% reduction in estimated mass loss as measured by SVET demonstrating the effectiveness of phosphate inhibitors for this alloy system.

  16. The effect of surface pre-conditioning treatments on the local composition of Zr-based conversion coatings formed on aluminium alloys

    Energy Technology Data Exchange (ETDEWEB)

    Cerezo, J. [Materials innovations institute (M2i), Mekelweg 2, Delft, 2628 CD (Netherlands); Delft University of Technology, Department of Materials Science and Engineering, Mekelweg 2, Delft, 2628 CD (Netherlands); Vandendael, I. [Vrije Universiteit Brussel, Research Group of Electrochemical and Surface Engineering, Pleinlaan 2 Brussels, B-1050 (Belgium); Posner, R. [Henkel AG & Co. KGaA, Henkelstr. 67, 40589 Dusseldorf (Germany); Wit, J.H.W. de [Delft University of Technology, Department of Materials Science and Engineering, Mekelweg 2, Delft, 2628 CD (Netherlands); Mol, J.M.C., E-mail: J.M.C.Mol@tudelft.nl [Delft University of Technology, Department of Materials Science and Engineering, Mekelweg 2, Delft, 2628 CD (Netherlands); Terryn, H. [Materials innovations institute (M2i), Mekelweg 2, Delft, 2628 CD (Netherlands); Delft University of Technology, Department of Materials Science and Engineering, Mekelweg 2, Delft, 2628 CD (Netherlands); Vrije Universiteit Brussel, Research Group of Electrochemical and Surface Engineering, Pleinlaan 2 Brussels, B-1050 (Belgium)

    2016-03-15

    Graphical abstract: - Highlights: • Field Emission Auger Electron Spectroscopy was used for local elemental analysis. • Acid and alkaline pre-conditioning treatments induces Cu-enrichment on AA6014. • A Cu-containing Zr-based conversion treatment for aluminium alloys was evaluated. • Cu-rich areas enhance the local formation of Zr-based conversion films on AA6014. • Thermal pre-conditioning treatments inhibits the formation of Zr-based coatings. - Abstract: This study investigates the effect of different alkaline, acidic and thermal pre-conditioning treatments applied to different Al alloy surfaces. The obtained results are compared to the characteristics of Zr-based conversion coatings that were subsequently generated on top of these substrates. Focus is laid on typical elemental distributions on the sample surfaces, in particular on the amount of precipitated functional additives such as Cu species that are present in the substrate matrix as well as in the conversion bath solutions. To this aim, Field Emission Auger Electron spectra, depth profiles and surface maps with superior local resolution were acquired and compared to scanning electron microscopy images of the sample. The results show how de-alloying processes, which occur at and around intermetallic particles in the Al matrix during typical industrial alkaline or acidic cleaning procedures, provide a significant source of crystallization cores for any following coating processes. This is in particular due for Cu-species, as the resulting local Cu structures on the surface strongly affect the film formation and compositions of state-of-the-art Zr-based films. The findings are highly relevant for industrial treatments of aluminium surfaces, especially for those that undergo corrosion protection and painting process steps prior to usage.

  17. MEMS/MOEMS foundry services at INO

    Science.gov (United States)

    García-Blanco, Sonia; Ilias, Samir; Williamson, Fraser; Généreux, Francis; Le Noc, Loïc; Poirier, Michel; Proulx, Christian; Tremblay, Bruno; Provençal, Francis; Desroches, Yan; Caron, Jean-Sol; Larouche, Carl; Beaupré, Patrick; Fortin, Benoit; Topart, Patrice; Picard, Francis; Alain, Christine; Pope, Timothy; Jerominek, Hubert

    2010-06-01

    In the MEMS manufacturing world, the "fabless" model is getting increasing importance in recent years as a way for MEMS manufactures and startups to minimize equipment costs and initial capital investment. In order for this model to be successful, the fabless company needs to work closely with a MEMS foundry service provider. Due to the lack of standardization in MEMS processes, as opposed to CMOS microfabrication, the experience in MEMS development processes and the flexibility of the MEMS foundry are of vital importance. A multidisciplinary team together with a complete microfabrication toolset allows INO to offer unique MEMS foundry services to fabless companies looking for low to mid-volume production. Companies that benefit from their own microfabrication facilities can also be interested in INO's assistance in conducting their research and development work during periods where production runs keep their whole staff busy. Services include design, prototyping, fabrication, packaging, and testing of various MEMS and MOEMS devices on wafers fully compatible with CMOS integration. Wafer diameters ranging typically from 1 inch to 6 inches can be accepted while 8-inch wafers can be processed in some instances. Standard microfabrication techniques such as metal, dielectric, and semiconductor film deposition and etching as well as photolithographic pattern transfer are available. A stepper permits reduction of the critical dimension to around 0.4 μm. Metals deposited by vacuum deposition methods include Au, Ag, Al, Al alloys, Ti, Cr, Cu, Mo, MoCr, Ni, Pt, and V with thickness varying from 5 nm to 2 μm. Electroplating of several materials including Ni, Au and In is also available. In addition, INO has developed and built a gold black deposition facility to answer customer's needs for broadband microbolometric detectors. The gold black deposited presents specular reflectance of less than 10% in the wavelength range from 0.2 μm to 100 μm with thickness ranging from

  18. Microchemistry in aluminium sheet production

    NARCIS (Netherlands)

    Lok, Z.J.

    2005-01-01

    The production of aluminium sheet alloys from as-cast ingots is a complex process, involving several rolling operations in combination with various thermal heat treatments. Through their influence on the alloy microchemistry and microstructure, these thermomechanical treatments are all aimed at cont

  19. Rolling process and bonding mechanism of micro-arc oxidation 6061 aluminium alloy clad plate%微弧氧化6061铝合金复合板轧制工艺及结合机理

    Institute of Scientific and Technical Information of China (English)

    郑艺; 吴国瑞; 张胜超; 张学术; 杨猛

    2014-01-01

    Micro-arc oxidation 6061 aluminium alloy clad plate was prepared by rolling which confirm the rolling composite feasibility of aluminum alloy plate .Bonding strength of the plate was tested by tear method and stripped surface was analyzed by SEM and EDS .The results show that aluminum alloy plate and micro-arc oxidation 6061 aluminium alloy plate can be bonded by rolling at the condition of rolling tempreture above 400 ℃and rolling reduction above 40%.During rolling, hardened layer on the aluminium alloy plate surface and ceramic layer on the micro-arc oxidation aluminium alloy plate surface ruptures , and ceramic particles involving in the interface bonding position , thus let the fresh aluminum alloy of the two plates extrude and the metallurgical bonding is obtained .%用轧制法制备了内含微弧氧化陶瓷颗粒的6061铝合金复合板,证实了微弧氧化铝合金板轧制复合可行性。用撕裂法测试了复合板的结合强度,对复合板剥离面进行了SEM和EDS分析。结果表明,在热轧温度不低于400℃,同时压下率不低于40%的轧制条件下,铝合金板/微弧氧化铝合金板通过轧制可以实现结合。在轧制时铝合金表面硬化层、微弧氧化铝合金表面陶瓷层破裂,陶瓷颗粒卷入界面结合处,复合板两侧铝合金新鲜金属挤出实现冶金结合。

  20. Hot-press Sintering and Properties of Al-Zn-Mg-Cu-Zr Aluminium Alloy%铝锌镁铜锆系铝合金的热压烧结及其性能

    Institute of Scientific and Technical Information of China (English)

    方攀; 李成章; 吴传栋; 罗国强; 沈强; 张联盟

    2013-01-01

    Using metal powder as raw material,Al-Zn-Mg-Cu-Zr aluminium alloys were prepared by hotpress sintering technology at different sintering temperatures.The density,phase,microstructure and mechanical properties of Al-Zn-Mg-Cu-Zr aluminium alloy specimens were measured.The results show that with the increase of sintering temperature,the porosity of the aluminium alloy decreased,but density increased,and the alloy had more homogeneous microstructure and better properties.When the sintering temperature was 600 ℃,the porosity was 0.01%,the aluminium alloy was close to completely dense and had a good degree of alloying.The maximum value of the average micro-hardness and tensile strength of the A1-Zn-Mg-Cu-Zr aluminium alloy specimen hit 174 HV and 502 MPa,respectively.The aluminium alloy with a high density,uniform structure and good mechanical property can be prepared by the hot-press sintering technology.%以金属粉体为原料,采用热压烧结技术在不同温度下烧结制备了铝锌镁铜锆系铝合金,并测试和分析了其密度、物相、显微组织以及力学性能.结果表明:随着烧结温度的升高,铝合金的气孔率降低,致密度上升,组织更均匀,性能更优异;当烧结温度为600℃时,气孔率低至0.01%,接近全致密,铝合金的合金化良好,显微硬度达到174 HV,抗拉强度达到502 MPa;采用热压烧结技术可以获得高致密度、组织均匀、力学性能良好的铝合金.

  1. Focus on Foundry Industry in China

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    @@ Till the latest issue is published, the CHINA FOUNDRY journal has started publication for two years. So far, nine issues of the CHINA FOUNDRY journal have been edited and published, and distributed to more than 50countries and regions.

  2. 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. Copyright © 2014 Elsevier Ltd and ISBI. All rights reserved.

  3. Some preliminary evaluations of black coating on aluminium AA2219 alloy produced by plasma electrolytic oxidation (PEO) process for space applications

    Science.gov (United States)

    Shrestha, S.; Merstallinger, A.; Sickert, D.; Dunn, B. D.

    2003-09-01

    This paper describes the results of a study of a black coating produced on aluminium AA2219 alloy using a process that involves creation of a hard ceramic oxide layer on the surface of the alloy by plasma electrolytic oxidation (PEO) known as the 'KERONITE®' process. Coating microstructure has been examined and the coating characteristics such as porosity, hardness, adhesion and phase composition were measured. The thermo-optical properties such as solar absorptance 'as' and normal infrared emittance 'en-IR' of the coating were measured in the 'as-prepared' condition and after environmental exposures to humidity, thermal cycling and UV-radiation in vacuum and to thermal shock. Comparison was made with alternative coatings produced using standard black anodising processes. The study also looked at the cold welding and friction behaviours of the coated alloy in vacuum and in an ambient laboratory environment. Standard spacecraft materials tests were conducted on the coated disc against an AISI 52100 steel ball and also against a coated pin using a pin-on-disc apparatus. Parameters such as friction coefficient and wear depth were measured and the cold welding behaviours were investigated. Test results were compared with the data generated for NiCr plated and anodised coatings. Corrosion performance was assessed using a salt spray exposure test and using an accelerated electrochemical test method. In addition, the study looked at the effect of post coating sealing with a sol-gel solution.

  4. Effect of Al–5Ti–1B grain refiner on the microstructure, mechanical properties and acoustic emission characteristics of Al5052 aluminium alloy

    Directory of Open Access Journals (Sweden)

    Amulya Bihari Pattnaik

    2015-04-01

    Full Text Available In the present investigation, the effect of Al–5Ti–1B grain refiner on the microstructure, mechanical properties and acoustic emission characteristics of Al 5052 aluminium alloy have been studied. Microstructural analysis showed the presence of primary α solid solution. No Al–Mg phase was found to be formed due to the presence of magnesium in the solid solution. The results indicated that the addition of Al–5Ti–1B grain refiner into the alloy caused a significant improvement in ultimate tensile strength (UTS and elongation values from 114 MPa and 7.8% to 185 MPa and 18% respectively. The main mechanisms behind this improvement were found to be due to the grain refinement during solidification and segregation of Ti at primary α grain boundaries. Acoustic emission (AE results indicated that intensity of AE signals increased with increase in Al–5Ti–1B master alloy content, which had been attributed to the combined effect of dislocation motion and grain refinement. The field emission scanning electron microscopy (FESEM and energy dispersive X-ray (EDX analysis were used to study the microstructure and fracture surfaces of the samples.

  5. 77 FR 32998 - Foundry Coke From China

    Science.gov (United States)

    2012-06-04

    ... COMMISSION Foundry Coke From China Determination On the basis of the record \\1\\ developed in the subject five... order on foundry coke from China would be likely to lead to continuation or recurrence of material... Commission are contained in USITC Publication 4326 (May 2012), entitled Foundry Coke from...

  6. Finite element modelling of shot peening and peen forming processes and characterisation of peened AA2024-T351 aluminium alloy

    Science.gov (United States)

    Gariepy, Alexandre

    The main purpose of this thesis was to develop and validate finite element (FE) simulation tools for shot peening and peen forming. The specific aim was to achieve quantitatively accurate predictions for both processes and demonstrate the potential of reliable FE modelling for scientific investigation and industrial applications. First, an improved dynamic impact model that takes into account the stochastic nature of shot peening was proposed by carefully studying its dimensions, introducing a dispersion of shot sizes and significantly reducing its computational cost. In addition, cyclic mechanical testing was conducted to define a suitable material constitutive theory for aluminium alloy (AA) 2024-T3/T351 subjected to shot peening. By combining a realistic shot peening model with an appropriate material law, fairly good residual stress predictions were achieved for three different sets of shot peening parameters. Second, an experimental and numerical characterization of AA2024-T351 shot peened with parameters representative of fatigue life improvement applications was conducted. Multiple techniques, such as micro-indentation, residual stress determination and electron backscatter diffraction, were combined to gain a better understanding of the influence of shot peening on the material. The potential uses of finite element simulation to complement experimental data were also studied. The material heterogeneity arising from the random impact sequence was investigated and it was found that the impact modelling methodology could provide useful information on such heterogeneities. Third, a novel peen forming simulation methodology was introduced. The impact model provided the necessary input data as part of a multiscale approach. Numerically calculated unbalanced induced stress profiles were input into shell elements and the deformed shape after peen forming was computed as a springback analysis. In addition, a simple interpolation method was proposed to model the

  7. 6061铝合金的电火花加工%Electrical discharge machining of 6061 aluminium alloy

    Institute of Scientific and Technical Information of China (English)

    A. PRAMANIK; A. K. BASAK; M. N. ISLAM; G. LITTLEFAIR

    2015-01-01

    在不同脉冲时间和导线张力下,研究6061铝合金电火花线切割加工过程中材料的去除率、切口/狭缝宽度、表面光洁度和线电极磨损,通过改变脉冲时间和导线张力,在电火花线切割加工机床上进行了8次实验.结果表明,随着脉冲时间的延长,材料的去除率增加,但导线张力不影响材料的去除率.较高的导线张力有利于促进加工工艺的稳定性,产生较低的线电极磨损和更好的表面光洁度.随着脉冲时间的变化,表面粗糙度没有明显变化.在所有加工条件下,表面外观非常相似.加工后表面包含凝固熔融材料、飞溅材料和气泡.由于热量输入的增加,脉冲时间的延长增大了线电极的磨损.线电极的磨损产生了斜槽,该斜槽正面的切口宽度比底部的宽.较高的电极损耗会产生较高的锥度.%The wire electrical discharge machining (EDM) of 6061 aluminium alloy in terms of material removal rate, kerf/slit width, surface finish and wear of electrode wire for different pulse on time and wire tension was studied. Eight experiments were carried out in a wire EDM machine by varying pulse on time and wire tension. It is found that the material removal rate increases with the increase of pulse on time though the wire tension does not affect the material removal rate. It seems that the higher wire tension facilitates steady machining process, which generates low wear in wire electrode and better surface finish. The surface roughness does not change notably with the variation of pulse on time. The appearance of the machined surfaces is very similar under all the machining conditions. The machined surface contains solidified molten material, splash of materials and blisters. The increase of the pulse on time increases the wear of wire electrode due to the increase of heat input. The wear of wire electrode generates tapered slot which has higher kerf width at top side than that at bottom side. The higher

  8. Registration of Crystallization Process of Ultra-Lightweight Mg-Li Alloys with Use of ATND Method

    Directory of Open Access Journals (Sweden)

    A. Białobrzeski

    2007-07-01

    Full Text Available Magnesium alloys are characterized by advantageous ratio of strength and/or elastic modulus to density, that is, can sustain static and dynamic loads similar to iron and aluminium, and additionally feature good vibration damping. Castings from magnesium alloys are lighter with about 20 – 30% than aluminium alloys and with 50 – 75% than iron alloys, that is why they are used in aviation and rocket industry and everywhere the weight of a product is of important significance for conditions of its operation. Also automotive industry introduces to vehicle’s structure an elements (castings manufactured from such alloys. On metallic matrix of magnesium alloys with lithium are also manufactured a composites reinforced with e.g. ceramic fiber, which are used as lightweight and resistant structure materials. The paper presents an attempt of implementation of ATND method (Thermal-Voltage-Derivative Analysis to monitoring of crystallization process of ultra-lightweight Mg-Li alloys. Investigated magnesium alloys with contents of about 2,3% Li, 10% Li and 11 % Li were produced in the Foundry Research Institute. Registration of melting and crystallization processes was made with use of the ATND method. Results of preliminary tests are shown in graphical form.

  9. EDTA容量法测定锌合金中的铝量%Determination of Aluminium in Zinc Alloy by EDTA Titrimelry

    Institute of Scientific and Technical Information of China (English)

    涂小红

    2009-01-01

    the abundant sample and nitric acid sample dissolving were adopted in the paper,then excess EDTA was added and titrated by zinc acetate acid in pH≈5.8, Aluminum EDTA complex was released after adding of ammonium fluoride.,then released EDTA was titrated by zinc acetic acid. The method was simple,rapid and accurate,it can be used to determine the aluminium in zinc alloy.%本文采用称大样和用硝酸溶样,然后加入过量的EDTA,在PH≈5.8时用乙酸锌滴定过量的EDTA,加入氟化铵,释放出与铝络合的EDTA,再用乙酸锌滴定被释放出的EDTA.该方法简单、快速、准确,适用于锌合金中铝量的测定.

  10. Observation of Built-up Edge Formation on a Carbide Cutting Tool with Machining Aluminium Alloy under Dry and Wet Conditions

    Directory of Open Access Journals (Sweden)

    Azlan U.A.A.

    2017-01-01

    Full Text Available This paper presents the morphology of built-up edge (BUE formation under wet and dry conditions with low and high cutting speeds. The workpiece materials and cutting tools selected for this work were aluminium alloy and canela carbide inserts graded PM25. The cutting tools underwent turning operation machining tests and their performance was evaluated by the flank wear and observation of the tool wear area. The machining tests were conducted at different spindle speeds and feed rates while the cut depth was kept constant. The analysis showed that formation of the BUE was dominant at low cutting speeds in dry conditions, but in wet conditions at high cutting speeds, a better performance was exhibited in terms of wear analysis.

  11. Simulation calculations for the positron annihilation in aluminium alloys for the study of the segregate formation; Simulationsrechnungen zur Positronenannihilation in Aluminiumlegierungen zur Untersuchung der Ausscheidungsbildung

    Energy Technology Data Exchange (ETDEWEB)

    Korff, Bjoern

    2010-11-29

    Highly solid aluminium alloys owe their properties to small, finely distributed segregations of alloy atoms. For the better understanding of the temperature treatment, which is required in order to control the segregate formation, it is important, to determine informations on the first early stages from few atoms. In the positron-annihilation spectroscopy (PAS) positrons are trapped in the vacancies of a solid and yield at their annihilation with surrounding electrons informations from their direct environment. because the formation of segregates requires a diffusion of the extraneous atoms by means of the vacancies, the PAS represents one of the few examination methods, by which already the formation of smallest segregations can be observed. By the comparison of measurement quantities of the PAS with simulations for different possible arrangements of extraneous atoms around the vacancy the atomic environment of the vacancy can be identified. In order to make this possible also in aluminium alloys, in which the number of the possible defect types is relatively large, a good description of the measurement values by the simulation is especially important. In the framework of this thesis the program AB2D was developed, by which the Doppler shift of the annihilation radiation can be determined. Contrarily to already existing approaches here valence-electron wave functions are used, which were calculated with the program ABINIT. By this way the main uncertainty by the description of the valence electrons in atomic superposition is cancelled. Because ABINIT is based on pseudopotentials, the projector augmented-wave method is used in order to describe the higher momenta of the electrons near the nuclei more realistically. With AB2D simulations for vacancy-extraneous-atom complexes and segregation phases in the alloy systems Al-Cu, Al-Mg-Cu, and Al-Mg-Si were performed. A comparison with measurements on samples, which were only few minutes stored at room temperature

  12. Influence of aluminium content on the physical, mechanical and sliding wear properties of zinc-based alloys

    Energy Technology Data Exchange (ETDEWEB)

    Prasad, B.K. [CSIR, Bhopal (India). Regional Res. Lab.; Patwardhan, A.K. [Roorkee Univ. (India). Dept. of Metallurgical Engineering; Yegneswaran, A.H. [CSIR, Bhopal (India). Regional Res. Lab.

    1997-04-01

    Attention has been focussed on the influence of Al content on the physical, mechanical and sliding wear properties of Zn-based alloys. Aspects studied include microstructure, density, electrical conductivity, hardness, tensile strength and elongation as well as sliding wear response of the alloys. Microstructural features of the alloys showed the presence of primary {alpha}, eutectic/eutectoid {alpha} + {eta} (depending on whether the alloy was hypereutectic/hypereutectoid with regard to the concentration of Al) along with the meta stable {epsilon} phase. The study suggests that it is possible to design and develop Zn-based alloys with a wide range of concentration of Al. The alloys in turn attain different combinations of physical, mechanical and wear properties which could suit a variety of engineering applications. Increasing the Al content in the alloy system proves beneficial within limits. In other words, there exists an optimum quantity of Al which could reap its advantage to the maximum extent. This of course varies with reference to a specific property of the alloy(s). The changing response of the alloys has been explained in terms of their microstructural features and the effects produced as a result of the test conditions maintained while characterizing the specimens. (orig.)

  13. 化学镀Ni-P合金在铝合金表面强化上的应用%Application of Electroless Plating Ni-P Alloy on Aluminium Alloy

    Institute of Scientific and Technical Information of China (English)

    朱晓云; 郭忠诚; 翟大成

    2001-01-01

    研究了化学镀镍-磷合金的性能,结果表明,热处理温度对镍-磷合金镀层硬度和耐磨性有较大的影响,二者经400℃×1 h热处理后达到峰值;镍-磷合金在酸、碱、盐介质中的耐蚀性优于1Cr18Ni9Ti不锈钢。应用结果证明,化学镀Ni-P合金在铝合金零部件上具有广泛的应用前景。%Properties of electroless plating Ni-Palloy have been studied, the results show that heattreatment temperature has a considerable effect onthe hardness and wear resistance of Ni-P alloy, andthey reach peak value after heat treatment at 400 ℃X 1h. Corrosion resistance of Ni-P alloy in acid,alkaline and salt media is superior to that of1Cr18Ni9Ti stainless steel. The electroless platingNi-P alloy has a wide application for the componentof aluminium alloy.

  14. The Progress and Prospect of Research on Aluminium Alloys for Auto Body Sheets%汽车铝合金车身板材的研究现状及发展趋势

    Institute of Scientific and Technical Information of China (English)

    关绍康; 姚波; 王迎新

    2001-01-01

    In recent years, with the development of society and advancement of technology, aluminium and aluminium alloys are used more and more widely. It becomes a trend that traditional steel sheets are replaced by aluminium sheets for auto body. The research progress, application status and development prospect of aluminium alloys for auto body sheets are summarized in this paper. Among the 2000, 5000 and 6000 series aluminium alloys now studied, the new style 6000 series Al-Mg-Si based alloy is specially introduced as a emphasis in future research.There are many advantages about it: proper strength and plasticity, good corrosion-resistance performance, easycoloring and effect of painting strengthening. Besides, some problems such as high cost and poor formation performance, which hold up the application of aluminium alloys for auto body sheets, are listed. At last, several advices are presented to develop characteristic alurninium alloys of high properties for auto body sheets in China. For instance, the stamping property should be improved by designing the compostition and technology and the relationship of stamping property, mechanical properties, composition and technology should be made clear, the material composition and technology can be designed by using computer techniques such as artificial neural network and genetic algo rithrn.%综述了国内外汽车铝合金2000、5000和6000系车身板的研究进程、应用现状及发展前景,指出了新型Al-Mg-Si基合金是今后汽车车身板研究应用的一个重点,它具有强度和塑性的良好组合,耐蚀性优良,易着色等优点;此外,还列出了汽车铝合金车身板研究应用中存在的成本高和成型性差等问题,提出了我国开发高性能且具有特色的汽车铝合金车身板材的研究方向。

  15. Influence of the composition and heat treatments in the mechanical properties of aluminium bronze alloys; Influencia de la composicion y el tratamiento termico en las propiedades mecanicas de aleaciones de bronce al aluminio

    Energy Technology Data Exchange (ETDEWEB)

    Cenoz-Echeverria, I.; Fernandez-Carrasquilla, J.

    2007-07-01

    Aluminium bronzes are copper-base alloys containing aluminium within the limits between 5-12%. Additions of Fe, Ni and Mn are used as alloying elements forming a family of complex alloys noted for their exceptional strength and corrosion resistance. In present paper sd the Ni:Fe ratio and heat treatments have been analyzed by determining the mechanical properties for three different aluminium bronze alloys containing Cu-Al10-Fe3, Cu-Al10-Fe5-Ni5 and Cu-Al10-Fe4-Ni8. The effect of as cast, quenched and quenched and tempered structures has been investigated regarding hardness, proof and ultimate tensile strength, elongation, modules of elasticity, Poisson ratio, fracture toughness, fatigue strength, crack propagation and Charpy impact properties. The influence of temperature has been studied by testing the elastic modules, Poisson ratio, the proof stress, tensile strength and the Charpy impact properties at -20 degree centigree, 24 degree centigree and 100 degree centigree. (Author)

  16. Molecular Foundry, Berkeley, California (Revised)

    Energy Technology Data Exchange (ETDEWEB)

    Carlisle, N.

    2008-03-01

    This case study provides information on the Molecular Foundry, which incorporates Labs21 principles in its design and construction. The design includes many of the strategies researched at Lawrence Berkeley Laboratory for energy efficient cleanroom and data centers. The result is an energy efficient high-performing sustainable laboratory.

  17. Dust exposure in Finnish foundries.

    Science.gov (United States)

    Siltanen, E; Koponen, M; Kokko, A; Engström, B; Reponen, J

    1976-01-01

    Dust measurements were made in 51 iron, 9 steel, and 8 nonferrous foundries, at which 4,316 foundrymen were working. The sampling lasted at least two entire shifts or work days continuously during various operations in each foundry. The dust samples were collected at fixed sites or in the breathing zones of the workers. The mass concentration was determined by weighing and the respirable dust fraction was separated by liquid sedimentation. The free silica content was determined by X-ray diffraction. In the study a total of 3,188 samples were collected in the foundries and 6,505 determinations were made in the laboratory. The results indicated a definite difference in the dust exposure during various operations. The highest dust exposures were found during furnace, cupola, and pouring ladle repair. During cleaning work, sand mixing, and shake-out operations excessive silica dust concentrations were also measured. The lowest dust concentrations were measured during melting and pouring operations. Moderate dust concentrations were measured during coremaking and molding operations. The results obtained during the same operations of iron and steel foundries were similar. The distribution of the workers into various exposure categories, the content of respirable dust and quartz, the correlation between respirable dust and total dust, and the correlation between respirable silica and total dust concentrations are discussed. Observations concerning dust suppression and control methods are briefly considered.

  18. The role of solidification rate in the corrosion resistance of a directionally solidified novel aluminium-lanthanum alloy

    Energy Technology Data Exchange (ETDEWEB)

    Dzib-Perez, L. [Programa de Corrosion del Golfo de Mexico, Universidad Autonoma de Campeche, Av. Agustin Melgar s/n, Col. Buenavista, CP 24030 Campeche, Campeche (Mexico); Gonzalez-Sanchez, J. [Programa de Corrosion del Golfo de Mexico, Universidad Autonoma de Campeche, Av. Agustin Melgar s/n, Col. Buenavista, CP 24030 Campeche, Campeche (Mexico)]. E-mail: jagonzal@uacam.mx; Perez, T. [Programa de Corrosion del Golfo de Mexico, Universidad Autonoma de Campeche, Av. Agustin Melgar s/n, Col. Buenavista, CP 24030 Campeche, Campeche (Mexico); Bartolo-Perez, P. [Programa de Corrosion del Golfo de Mexico, Universidad Autonoma de Campeche, Av. Agustin Melgar s/n, Col. Buenavista, CP 24030 Campeche, Campeche (Mexico); CINVESTAV-Merida, Applied Physics Department, Carr. antigua a Progreso, km 6, CP 97310 Merida, Yucatan (Mexico); Juarez, A. [CIATEQ. Calzada del Retablo 150, CP 76150 Queretaro, Queretaro (Mexico)

    2006-08-15

    The corrosion resistance of a novel Al-12.6 wt.%La alloy manufactured using unidirectional solidification was studied by sensitive electrochemical techniques. It was found that the electrochemical behaviour of the alloy depends upon the formation of non-passive corrosion product layers. Different solidification rates produced dissimilar microstructures which promoted selective dissolution when the alloy was anodically polarized in distilled water. A model for the electrochemical behaviour of this alloy was proposed based on an equivalent circuit that simulated the impedance results.

  19. Review on Plating Technology of Aluminium and Aluminium Alloy%铝及铝合金电镀研究进展

    Institute of Scientific and Technical Information of China (English)

    蔡婷婷; 王兆文

    2013-01-01

    铝及铝合金电镀层具有优良的防腐性能及装饰性能,广泛应用金属防护和表面装饰等领域。本文针对铝和铝合金电镀研究及发展状况,在电镀基体、电镀层成分、电镀体系、电镀添加剂等几个方面进行文献综述,其中主要对熔盐电镀金属铝及合金的发展作重点论述,并对近年来发展的一些新的电镀技术进行了介绍。本文在文献综述的基础上,结合我们在熔盐电镀领域的研究经验,对熔盐电镀铝的方法及研究成果进行分析总结,旨在推动铝与铝合金电镀技术的发展。%The aluminum and its alloy are widely used in the field of metal surface protection and surface decoration for their excellent corrosion resistance ability and fine appearance . The current research and development are reviewed in this paper , meanwhile the related literature are summarized into the following parts:the electrodeposition substrate , the content of electrodeposites , the reaction systems and the addictives . New techniques introduced into this area are mentioned and the molten salt system was emphasized especially . With the notion and experience aquired from years of study on molten salts , we proposed the analysis on the research techniques and achievements , in aim to impulse the progress in the aluminum electrodeposition area .

  20. An improved billet on billet extrusion process of continuous aluminium alloy shapes for cryogenic applications in the Compact Muon Solenoid experiment

    CERN Document Server

    Tavares, S S

    2003-01-01

    The Compact Muon Solenoid (CMS) is one of the experiments being designed in the framework of the Large Hadron Collider accelerator at CERN. CMS will contain the largest and the most powerful superconducting solenoid magnet ever built in terms of stored energy. It will work at 4.2 K, will have a magnetic length of 12.5 m, with a free bore of 6m and will be manufactured as a layered and modular structure of NbTi cables embedded in a high purity (99.998%) Al- stabiliser. Each layer consists of a wound continuous length of 2.55 km. In order to withstand the high electromagnetic forces, two external aluminium alloy reinforcing sections are foreseen. These reinforcements, of 24 mm multiplied by 18 mm cross-section, will be continuously electron beam (EB) welded to the pure Al-stabiliser. The alloy EN AW-6082 has been selected for the reinforcements due to its excellent extrudability, high strength in the precipitation hardened state, high toughness and strength at cryogenic temperatures and ready EB weldability. Ea...

  1. The effect of surface pre-conditioning treatments on the local composition of Zr-based conversion coatings formed on aluminium alloys

    Science.gov (United States)

    Cerezo, J.; Vandendael, I.; Posner, R.; de Wit, J. H. W.; Mol, J. M. C.; Terryn, H.

    2016-03-01

    This study investigates the effect of different alkaline, acidic and thermal pre-conditioning treatments applied to different Al alloy surfaces. The obtained results are compared to the characteristics of Zr-based conversion coatings that were subsequently generated on top of these substrates. Focus is laid on typical elemental distributions on the sample surfaces, in particular on the amount of precipitated functional additives such as Cu species that are present in the substrate matrix as well as in the conversion bath solutions. To this aim, Field Emission Auger Electron spectra, depth profiles and surface maps with superior local resolution were acquired and compared to scanning electron microscopy images of the sample. The results show how de-alloying processes, which occur at and around intermetallic particles in the Al matrix during typical industrial alkaline or acidic cleaning procedures, provide a significant source of crystallization cores for any following coating processes. This is in particular due for Cu-species, as the resulting local Cu structures on the surface strongly affect the film formation and compositions of state-of-the-art Zr-based films. The findings are highly relevant for industrial treatments of aluminium surfaces, especially for those that undergo corrosion protection and painting process steps prior to usage.

  2. Corrosion protection of AA 2024-T3 aluminium alloys using 3, 4-diaminobenzoic acid chelated zirconium-silane hybrid sol-gels

    Energy Technology Data Exchange (ETDEWEB)

    Varma, P.C. Rajath; Colreavy, John [Centre for Research on Engineering Surface Technology (CREST), FOCAS Institute, Dublin Institute of Technology, 13 Camden Row, Dublin 8 (Ireland); Cassidy, John [School of Chemical and Pharmaceutical Sciences, Dublin Institute of Technology, Kevin St., Dublin 8 (Ireland); Oubaha, Mohamed; McDonagh, Colette [National Centre for Sensor Research (NCSR), Dublin City University, Dublin 9 (Ireland); Duffy, Brendan, E-mail: bduffy@dit.i [Centre for Research on Engineering Surface Technology (CREST), FOCAS Institute, Dublin Institute of Technology, 13 Camden Row, Dublin 8 (Ireland)

    2010-08-02

    Organic-inorganic polymers formed by hydrolysis/condensation reactions of alkoxide precursors, such as organically modified silanes (Ormosils) are used for several industrial applications such as electronic, optical and protective anticorrosion coatings. Such materials possess superior chemical stability, physical strength and scratch resistance characteristics when compared to organic polymers. Further performance improvement can be achieved through the incorporation of zirconium and titanium based nanoparticles, also formed through from precursors via the sol-gel process. However due to the inherent reactivity differences of the above precursors, they must be hydrolysed separately before being combined for final condensation. Zirconium precursors are commonly chelated using acetic acid or acetyl acetonate prior to hydrolysis, to lower the hydrolysis rate. In this body of work, 3,4-diaminobenzoic acid (DABA) and acetyl acetonate (acac) were compared as chelating ligands for controlling the hydrolysis reactions of zirconium n-propoxide to form nanoparticles within a silane sol matrix. The sols were applied as coatings on aerospace grade aluminium alloy AA 2024-T3 and characterised by physical, spectroscopical, microscopical, electrochemical and calorimetric techniques. The electrochemical properties of the coatings, as characterised by EIS and PDS, correlated with neutral salt spray evaluations confirming that the use of DABA as a chelating ligand significantly improved the coating performance when compared to the traditional diketone ligand. The data indicates the anticorrosion properties of the nitrogen rich chelate have a key role in protecting the alloy through the formation of smaller zirconium nanoparticles, thus improving the polymer network stability.

  3. Effect of Tool Geometry and Welding Speed on Mechanical Properties and Microstructure of Friction Stir Welded Joints of Aluminium Alloys AA6082-T6

    Directory of Open Access Journals (Sweden)

    Patil Hiralal Subhash

    2014-12-01

    Full Text Available Friction stir welding is a solid state innovative joining technique, widely being used for joining aluminium alloys in aerospace, marine automotive and many other applications of commercial importance. The welding parameters and tool pin profile play a major role in deciding the weld quality. In this paper, an attempt has been made to understand the influences of welding speed and pin profile of the tool on friction stir welded joints of AA6082-T6 alloy. Three different tool pin profiles (tapered cylindrical four flutes, triangular and hexagonal have been used to fabricate the joints at different welding speeds in the range of 30 to 74 mm/min. Microhardness (HV and tensile tests performed at room temperature were used to evaluate the mechanical properties of the joints. In order to analyse the microstructural evolution of the material, the weld’s cross-sections were observed optically and SEM observations were made of the fracture surfaces. From this investigation it is found that the hexagonal tool pin profile produces mechanically sound and metallurgically defect free welds compared to other tool pin profiles.

  4. Increasing strength, ductility and impact toughness of ultrafine-grained 6063 aluminium alloy by combining ECAP and a high-temperature short-time aging

    Science.gov (United States)

    Meyer, L. W.; Schönherr, R.; Hockauf, M.

    2010-07-01

    Since fully-dense ultrafine or nanocrystalline bulk materials can be processed, there has been an increasing scientific interest in several plastic deformation (SPD) procedures, particularly in the last decade. Especially the equal-channel angular pressing (ECAP) has widely been investigated due to its ability of producing billets sufficiently large for industrial applications in functional or structural components. The significant strength increase based on grain refinement is typically accompanied by a significant decrease in ductility and toughness. Within this work, a new methodology was applied for combining ECAP with a subsequent high-temperature short-time aging for the 6063 aluminium alloy. An increase in strength, ductility as well as impact toughness regarding its coarse grained counterparts was reached. More precisely, ultimate tensile strength, elongation to failure and impact toughness were increased by 46%, 21% and 40% respectively. This was observed after only one run of ECAP at room temperature in a solid-solution treated condition and an aging at 170° C for 18 minutes. The regular aging time for maximum strength at 170° C is around 6 hours. Longer exposure times lead to recrystallisation and, as for regular aging, it leads to overaging, both causing a decrease of properties. The work demonstrates a strategy for an efficient processing of commercial Al-Mg-Si alloys with outstanding mechanical properties.

  5. Increasing strength, ductility and impact toughness of ultrafine-grained 6063 aluminium alloy by combining ECAP and a high-temperature short-time aging

    Energy Technology Data Exchange (ETDEWEB)

    Meyer, L W; Schoenherr, R; Hockauf, M, E-mail: robert.schoenherr@mb.tu-chemnitz.d [Chemnitz University of Technology, Materials and Impact Engineering, D-09107 Chemnitz (Germany)

    2010-07-01

    Since fully-dense ultrafine or nanocrystalline bulk materials can be processed, there has been an increasing scientific interest in several plastic deformation (SPD) procedures, particularly in the last decade. Especially the equal-channel angular pressing (ECAP) has widely been investigated due to its ability of producing billets sufficiently large for industrial applications in functional or structural components. The significant strength increase based on grain refinement is typically accompanied by a significant decrease in ductility and toughness. Within this work, a new methodology was applied for combining ECAP with a subsequent high-temperature short-time aging for the 6063 aluminium alloy. An increase in strength, ductility as well as impact toughness regarding its coarse grained counterparts was reached. More precisely, ultimate tensile strength, elongation to failure and impact toughness were increased by 46%, 21% and 40% respectively. This was observed after only one run of ECAP at room temperature in a solid-solution treated condition and an aging at 170{sup 0} C for 18 minutes. The regular aging time for maximum strength at 170{sup 0} C is around 6 hours. Longer exposure times lead to recrystallisation and, as for regular aging, it leads to overaging, both causing a decrease of properties. The work demonstrates a strategy for an efficient processing of commercial Al-Mg-Si alloys with outstanding mechanical properties.

  6. Quality Index of the AlSi7Mg0.3 Aluminium Casting Alloy Depending on the Heat Treatment Parameters

    Directory of Open Access Journals (Sweden)

    Czekaj E.

    2016-09-01

    Full Text Available Issues connected with high quality casting alloys are important for responsible construction elements working in hard conditions. Traditionally, the quality of aluminium casting alloy refers to such microstructure properties as the presence of inclusions and intermetallic phases or porosity. At present, in most cases, Quality index refers to the level of mechanical properties – especially strength parameters, e.g.: UTS, YS, HB, E (Young’s Modulus, K1c (stress intensity factor. Quality indexes are often presented as a function of density. However, generally it is known, that operating durability of construction elements depends both on the strength and plastic of the material. Therefore, for several years now, in specialist literature, the concept of quality index (QI was present, combines these two important qualities of construction material. The work presents the results of QI research for casting hypoeutectic silumin type EN AC-42100 (EN AC-AlSi7Mg0.3, depending on different variants of heat treatment, including jet cooling during solution treatment.

  7. Rapidly solidified aluminium for optical applications

    NARCIS (Netherlands)

    Gubbels, G.P.H.; Venrooy, B.W.H. van; 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

  8. Electron Conditioning of Technical Aluminium Surfaces

    Energy Technology Data Exchange (ETDEWEB)

    Le Pimpec, F

    2004-09-02

    The effect of electron conditioning on commercially aluminium alloys 1100 and 6063 were investigated. Contrary to the assumption that electron conditioning, if performed long enough, can reduce and stabilize the SEY to low values (= 1.3, value of many pure elements [1]), the SEY of aluminium did not go lower than 1.8. In fact, it reincreases with continued electron exposure dose.

  9. 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.

  10. Inhibition Behaviour of 2-butine1, 4diol and Tartrate Salt, and Their Synergistic Effects on Corrosion of AA3003 Aluminium Alloy in 0.5% NaCl Solution

    Institute of Scientific and Technical Information of China (English)

    Taghi Shahrabi; Alireza Yazdzad; Mirghasem Hosseini

    2008-01-01

    This work intends to investigate the inhibition behaviour of 2-butine 1, 4diol and potassium sodium tartrate and their synergistic effects on 3003 aluminium alloy corrosion in 0.5% NaCl solution. Experiments were carried out by electrochemical impedance spectroscopy (EIS) and Tafel polarization method in a three-electrode cell. It was concluded that the inhibition efficiencies increased with an increase in the concentrations of inhibitors. For 2-butinel, 4diol and tartrate salt, the optimum in the inhibition efficiency, at room temperature and neutral pH, was observed for concentrations close to 10-3 mol/L and 1.5×10-3mol/L, respectively. The electrochemical results illustrated that 2-butine1, 4diol and tartrate salt, have significant synergistic inhibition effects on corrosion of 3003 aluminium alloy in 0.5% NaCl solution. The optimum ratio of concentrations for tartrate to alcohol was 2:1.

  11. Study of the uniform corrosion of an aluminium alloy used for the fuel cladding of the Jules Horowitz experimental reactor; Etude de la corrosion uniforme d'un alliage d'aluminium utilise comme gainage du combustible nucleaire du reacteur experimental Jules Horowitz

    Energy Technology Data Exchange (ETDEWEB)

    Wintergerst, M. [CEA Saclay, Dept. des Materiaux pour le Nucleaire (DEN/DANS/DMN/SEMI), 91 - Gif-sur-Yvette (France)

    2008-07-01

    For the Jules Horowitz new material testing reactor, an aluminium base alloy, AlFeNi, will be used for the cladding of the fuel plates. Taking into account the thermal properties of the alloy and of its oxide, the corrosion of the fuel cans presents many problems. The aim of this thesis is to provide a growing kinetic of the oxide layer at the surface of the AlFeNi fuel can in order to predict the life time of fuel element. Thus the mechanism of degradation of the cladding will be describe in order to integrate the different parameters of the operating reactor. (A.L.B.)

  12. Evaluation of the load-carrying capacity of hard coatings deposited onto a 7075-T6 aluminium alloy; Evaluacion de la capacidad de soporte de carga de recubrimientos duros depositados sobre la aleacion de aluminio 7075-T6

    Energy Technology Data Exchange (ETDEWEB)

    Moreno, E. T.; Santana, Y. Y.; Castro, A. C.; Puchi-Cabrera, E. S.; Staia, M. H.

    2007-07-01

    In the present work, the effect of the thickness of an electroless NiP load-support interlayer coating, on the initiation and development of plastic deformation in a 7075-T6 aluminium alloy substrate coated with a duplex coatings has been investigated. The duplex system has been obtained by means of the deposition of an electroless Ni-11 wt.% P (EN) onto the aluminium alloy substrate, followed by the deposition of a ZrN film (PVD) on top of the EN coating. The duplex systems that were investigated involved two different EN deposits, with thicknesses of 30 and 60 mm, respectively. The coatings were characterized regarding their morphology, thickness and absolute hardness. Indentation tests with spherical ind enters were performed employing 6 mm diameter WC-6Co balls and normal loads of 10,15, 25,50 and 75 N. All the indentations were modeled by means of the Elastic 2.1. code, in order to determine the through-thickness von Misses effective stress profile of the samples and the critical load for the initiation of the plastic deformation of the aluminium alloy substrate. the experimental results have been validate by means of such a theoretical analysis. it has been determined that the duplex system with an EN interlayer of 30 mm does not constitute a satisfactory load-support interlayer, for the load values employed in the tests. However, for the coated system with an EN interlayer of 60 mm, the critical load for the initiation of plastic deformation in the aluminium alloy substrate was found to be{approx}16N, which indicates that such a load-support interlayer avoids the plastic deformation of the substrate at normal loads less than {approx} 15 N. (Author) 21 refs.

  13. Circular economy: To be or not to be in a closed product loop? A Life Cycle Assessment of aluminium cans with inclusion of alloying elements

    DEFF Research Database (Denmark)

    Niero, Monia; Olsen, Stig Irving

    2016-01-01

    Packaging, representing the second largest source of aluminium scrap at global level, deserves a key role in the transition towards the circular economy. Life Cycle Assessment (LCA) of aluminium products has been typically based on one life cycle considering pure aluminium flows and neglecting...

  14. Aluminium bridges, aluminium bridge decks

    NARCIS (Netherlands)

    Soetens, F.; Straalen, IJ.J. van

    2003-01-01

    Applications of aluminium have grown considerably in building and civil engineering the last decade. In building and civil engineering the increase of aluminium applications is due to various aspects like light weight, durability and maintenance, use of extrusions, and esthetics. The paper starts

  15. Aluminium bridges, aluminium bridge decks

    NARCIS (Netherlands)

    Soetens, F.; Straalen, IJ.J. van

    2003-01-01

    Applications of aluminium have grown considerably in building and civil engineering the last decade. In building and civil engineering the increase of aluminium applications is due to various aspects like light weight, durability and maintenance, use of extrusions, and esthetics. The paper starts wi

  16. Web based foundry knowledge base

    Directory of Open Access Journals (Sweden)

    A. Stawowy

    2009-01-01

    Full Text Available The main assumptions and functions of proposed Foundry Knowledge Base (FKB are presented in this paper. FKB is a framework forinformation exchange of casting products and manufacturing methods. We use CMS (Content Management System to develope andmaintain our web-based system. The CastML – XML dialect developed by authors for description of casting products and processes – isused as a tool for information interchange between ours and outside systems, while SQL is used to store and edit knowledge rules and alsoto solve the basic selection problems in the rule-based module. Besides the standard functions (companies data, news, events, forums and media kit, our website contains a number of nonstandard functions; the intelligent search module based on expert system is the main advantage of our solution. FKB is to be a social portal which content will be developed by foundry community.

  17. From famous foundry to 'supersurgery'.

    Science.gov (United States)

    Mann, Steve

    2014-02-01

    Dr Steve Mann, a partner at the Worcester Street Medical Practice in Stourbridge, describes how he and a number of his GP colleagues have worked with architects, Abacus Architects, and main contractor, Amphion Construction, as well as with a number of local NHS and local authority bodies, to co-ordinate construction of a new GP 'supersurgery' - the realisation of a dream - on the former site of what is believed to be one of England's oldest foundries in the West Midlands town. The architects' view on the scheme, one of the key goals of which is to retain both much of the character, and the unusual original metal sub-structure, of the former foundry, is also given.

  18. A quantitative evaluation of the deformation texture predictions for aluminium alloys from crystal plasticity finite element method

    Science.gov (United States)

    Li, Saiyi; Van Houtte, Paul; Kalidindi, Surya R.

    2004-09-01

    Crystal plasticity finite element (CPFE) models are useful tools in modelling the anisotropic stress-strain responses in large deformation of polycrystalline metals. In this study, a CPFE model is applied to simulate the evolution of crystallographic textures during cold rolling of hot-rolled aluminium plates and during uniaxial tensile, uniaxial compression and simple shear tests of annealed aluminium sheets. The performance of the model is critically evaluated through quantitative comparisons of the simulated textures with those predicted by the full constraints (FC) Taylor model and the experimentally measured textures. It is shown that the CPFE model performs better than the FC Taylor model in all the cases. However, the quality of the texture predictions deteriorates with increasing strain values. The CPFE model gives better texture predictions in the moderately deformed tensile and compression samples (~20% strain), compared to the more heavily deformed simple shear (0.85-0.95 shear strain) and cold-rolled (40-98% thickness reduction) samples. It is also shown that the CPFE predictions for cold rolling can be improved with finer discretization, i.e. by assigning multiple elements per grain instead of one element per grain in the finite element model. The improvement is mainly reflected in an improved prediction of the copper component and, in some cases, an improved prediction of the brass component. Inspection of the local deformation gradients reveals that these texture changes can be attributed to the increase of shear relaxations in the RD-ND and RD-TD planes.

  19. Status and Development of China Foundry Mould Industry

    Institute of Scientific and Technical Information of China (English)

    2005-01-01

    @@ With the development of automotive industry and mechanical manufacturing industry of China, the foundry industry in the country has been continuously growing.Foundry moulds, which are called "the mother of foundry"have been paid more and more attention.

  20. Environmental Bioassay Evaluation of Foundry Waste Residuals

    OpenAIRE

    Bastian, Kenneth Chad; Alleman, James E.

    1996-01-01

    Although the constructive reuse of foundry residuals represents a decidedly beneficial goal with distinct economic and environmental benefits, potential end-users are nonetheless reluctant to use these residuals, given an inherent concern about potential unforeseen environmental liabilities. Results of foundry residual leachate characterization to date strongly suggest that many ferrous foundries are discarding sands whose quality is fully amenable to their future use with embankment constru...

  1. Environmental Protection Versus Foundry Engineering Practice

    OpenAIRE

    Maj M.; Werrtz J.; Piekło J.

    2017-01-01

    • Theory and practice of environmental protection in the case of foundries in Europe and Asia • Experience resulting from the cooperation with the foundries in a few European countries, China and India • Phenomena and factors affecting the pollution of the natural environment and the implementation of measures aiming at the environmental protection. Every specialist dealing with foundry processes and their impact on environmental pollution must have encountered in their professional careers n...

  2. Kocel Steel Foundry Grand Opening Ceremony

    Institute of Scientific and Technical Information of China (English)

    TIAN Shi-jiang

    2006-01-01

    @@ On May 9, 2006 the Grand Opening ceremony of Kocel Steel Foundry Co., Ltd. was held in the National Economic and Technological Development Zone in Yinchuan City, Ningxia, China. Kocel Steel Foundry Co.,Ltd. is a large scale enterprise producing steel castings and it is jointly established by Ningxia Kocel Group,Changcheng Suzaki Machine & Foundry Co., Ltd. and Voestalpine Giesserei Linz GmbH, Austria.

  3. The Eleventh National Foundry Congress of FICMES with China Foundry Week 2006

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    @@ The Eleventh National Foundry Congress, an event given every four years by Foundry Institution of Chinese Mechanical Engineering Society (FICMES) and the once a year's China Foundry Week were held on September 18-24, 2006 in Xi'an, Shaanxi province.

  4. Possibilities of utilizing 3DP technology for foundry mould making

    Directory of Open Access Journals (Sweden)

    G. Budzik

    2007-04-01

    Full Text Available Possibilities of application of three-dimensional printing (3DP technology for making casting prototypes are discussed. Three-dimensional printing enables making of foundry moulds for elements of complex shapes. The mould presented in the paper was printed with the use of Z510 Spectrum unit in the Car Technology Sp. z o.o. (Ltd. Co. in Kraków. The basic material for printing foundry moulds is the ZCast 501 powder. This powder is a mixture of traditional molding sand, gypsum and supplementary ingredients. The mould is made in ZCast technology, and it enables casting of zinc, magnesium and aluminum alloys at max. pouring temperature of 1100°C. The paper describes research on the possibility to utilize a standard ZP14 powder for building a rotor blade casting moulds. The research has showed that the ZP14 powder may serve for printing foundry moulds, which should then be subjected to thermo-chemical treatment. Application of the basic ZPrint system powder permits a reduction in mould manufacturing costs.

  5. Effects of quench rate and natural ageing on the age hardening behaviour of aluminium alloy AA6060

    Energy Technology Data Exchange (ETDEWEB)

    Strobel, Katharina, E-mail: katharina.strobel@aol.com [CAST Co-operative Research Centre, Department of Materials Engineering, Monash University, Clayton, Victoria 3800 (Australia); Lay, Matthew D.H., E-mail: mlay@fbrice.com [CSIRO Manufacturing Flagship, Clayton, Victoria 3169 (Australia); Easton, Mark A., E-mail: mark.easton@rmit.edu.au [CAST Co-operative Research Centre, Department of Materials Engineering, Monash University, Clayton, Victoria 3800 (Australia); Sweet, Lisa, E-mail: lisa.sweet@monash.edu [CAST Co-operative Research Centre, Department of Materials Engineering, Monash University, Clayton, Victoria 3800 (Australia); Zhu, Suming, E-mail: suming.zhu@rmit.edu.au [CAST Co-operative Research Centre, Department of Materials Engineering, Monash University, Clayton, Victoria 3800 (Australia); Parson, Nick C., E-mail: nick.parson@riotinto.com [Rio Tinto Alcan, Arvida Research and Development Centre, 1955, Mellon Blvd, Jonquière, Québec G7S 4K8 (Canada); Hill, Anita J., E-mail: anita.hill@csiro.au [CSIRO Manufacturing Flagship, Clayton, Victoria 3169 (Australia)

    2016-01-15

    Quench sensitivity in Al–Mg–Si alloys has been largely attributed to the solute loss at the heterogeneous nucleation sites, primarily dispersoids, during slow cooling after extrusion. As such, the number density of dispersoids, the solute type and concentration are considered to be the key variables for the quench sensitivity. In this study, quench sensitivity and the influence of natural ageing in a lean Al–Mg–Si alloy, AA6060, which contains few dispersoids, have been investigated by hardness measurement, thermal analysis, transmission electron microscopy (TEM) and positron annihilation lifetime spectroscopy (PALS). It is shown that the quench sensitivity in this alloy is associated with the degree of supersaturation of vacancies after cooling. Due to vacancy annihilation and clustering during natural ageing, the quench sensitivity is more pronounced after a short natural ageing time (30 min) compared to a longer natural ageing time (24 h). Therefore, prolonged natural ageing not only leads to an increase in hardness, but can also have a positive effect on the quench sensitivity of lean Al–Mg–Si alloys. - Highlights: • Significant quench sensitivity observed in AA6060 alloy after 30 min natural ageing • Prolonged natural ageing increased hardness and reduced QS. • Low dispersoid density leads to insignificant QS from non-hardening precipitates. • Vacancy supersaturation identified as a contributor to QS.

  6. Light-weight aluminium bridges and bridge decks. An overview of recent applications

    NARCIS (Netherlands)

    Maljaars, J.; Soetens, F.; Kluyver, D. de

    2008-01-01

    The last decades have shown a large increase in the application of aluminium alloys for light-weight bridges. For bridge construction, aluminium alloys have some specific advantages, but also some points of attention. This paper deals with some recent projects of aluminium bridges, and for these pro

  7. Light-weight aluminium bridges and bridge decks. An overview of recent applications

    NARCIS (Netherlands)

    Maljaars, J.; Soetens, F.; Kluyver, D. de

    2008-01-01

    The last decades have shown a large increase in the application of aluminium alloys for light-weight bridges. For bridge construction, aluminium alloys have some specific advantages, but also some points of attention. This paper deals with some recent projects of aluminium bridges, and for these

  8. Investigation of the Wear and Hardness Behaviour of Aluminium Alloy Coated Using the Powder Flame Spraying Method

    Directory of Open Access Journals (Sweden)

    Nurullah KIRATLI

    2009-03-01

    Full Text Available In this study, the wear behavior of aluminum alloy AL 5754 ( Etial 53 coated with powders of 10Al-Cu alloy (RotoTec® 19850 and 15Cr7Fe-Ni alloy (RotoTec® 19985 using powder flame spraying method has been investigated. To avoid thermal expansions between substrate and coating materials, Ni-Al RotoTec® 51000 was used as binding material. The wear test was performed on a pin-on-disc test apparatus. As an abrasive material, a SiC, 800 sandpaper was used. The wear tests of coated materials were carried out at room temperature and at 1.0m/s sliding speed with 0.35 and 0.70MPa pressures. To characterize coated specimens, they have been examined with optical microscope. As a result, it is found that the both coating materials have improved wear resistance.

  9. Effect of stress ratio and frequency on fatigue crack growth rate of 2618 aluminium alloy silicon carbide metal matrix composite

    Indian Academy of Sciences (India)

    Nirbhay Singh; Ram Khelawan; G N Mathur

    2001-04-01

    Effect of stress ratio and frequency on the fatigue crack propagation of 2618 aluminium alloy–silicon carbide composite were investigated at ambient temperature. With the first set of specimens, the fatigue crack growth rates were studied at three frequencies of 1 Hz, 5 Hz and 10 Hz at a stress ratio of 0.1 whereas the effects of stress ratios of 0.1, 0.25 and 0.50 were studied with the second set of specimens. The study showed that the fatigue crack propagation behaviour of this metal matrix composite was influenced to an appreciable extent by the stress ratio, but not by the fatigue frequencies used in this investigation.

  10. Welding Stress and Welding Distortion of 6061 Aluminium Alloy Thin Plate%6061铝合金薄板焊接应力与焊接变形

    Institute of Scientific and Technical Information of China (English)

    陈丽华; 封艳

    2013-01-01

    the relationship between the plate size, welding current, welding voltage and welding stress, the welding distortion for 6061 aluminum alloy sheet TIG welding is studied. With the increase of welding current, welding voltage,aluminium alloy of the longitudinal and lateral contraction deformation increase; With the increase of the length of the plate, due to the much more constraint, the plate of the longitudinal residual deformation decrease,for the bending stress in thickness direction increases,the transverse deformation increases. Residual stress of welding is tensile, and the parent metal close to weld is compressive stress, and the rest of the parent metal is tensile stress, the more the welding energy is, the greater the residual stress.%研究了6061铝合金薄板TIG焊焊接应力、焊接变形与焊接电流、焊接电压和板材尺寸的关系.随着焊接线能量的增加,铝合金的纵向和横向收缩变形增加;随着板的长度的增加,由于约束增加,板的纵向残余变形减少,厚度方向的抗弯增大,横向变形增大.板焊后,焊缝处受拉应力,而紧靠焊缝的母材处却受压应力,其余部分受拉应力且焊接线能量越大,残余应力越大.

  11. Characterization of surface liquid segregation in SSM-HPDC aluminium alloys 7075, 2024, 6082 and A201

    CSIR Research Space (South Africa)

    Moller, H

    2010-09-01

    Full Text Available analysis. Chemical profiles of the main alloying elements were plotted for the cross-section of the plates in the as-cast and T6 (after solution treatment) temper conditions. Vickers hardness profiles from the surface to the centre of the plates were...

  12. Influence of surface liquid segregation on corrosion behavior of semi-solid metal high pressure die cast aluminium alloys

    CSIR Research Space (South Africa)

    Masuku, EP

    2010-09-01

    Full Text Available alloys 7075-T6 and 2024-T6. Potentiodynamic testing was performed in deaerated 3.5%NaCl solution. In separate tests, the open-circuit potential was monitored in aerated 3.5% NaCl for 30 minutes after immersion. The electrochemical tests show...

  13. 6061铝合金板材锯齿形屈服行为的研究%Study of Serrated Yielding in 6063 Aluminium Alloy Board

    Institute of Scientific and Technical Information of China (English)

    孙萍; 刘程; 王辉

    2012-01-01

    The stress drop amplitude and the duration of the serration, etc. of serrated yielding effect in 6063 aluminium alloy are analyzed systematically, and the influence of serrated yielding effect on mechanical properties is discussed. The results show that the stress drop amplitude number, drop duration and its number, reloading time and its number decrease when the strain rate increases. The serrated yielding effect is weakest and the mechanical properties are best when the strain rate is 1.4×10^-3s^-1%对6061铝合金板材锯齿形屈服行为中应力跌幅、跌落时间等多个特征物理量随应变率的变化规律进行了系统的研究,探讨了锯齿形行为对材料力学性能的影响。结果表明,应力跌幅个数,跌落时间及其个数,再加载时间及其个数均随着应变率的增大而逐渐减少;当应变率为1.4×10^-3s^-1时,6061铝合金板材的锯齿形屈服行为最弱,板材的力学性能最好。

  14. Comparison of fatigue crack growth of riveted and bonded aircraft lap joints made of Aluminium alloy 2024-T3 substrates - A numerical study

    Science.gov (United States)

    Pitta, S.; Rojas, J. I.; Crespo, D.

    2017-05-01

    Aircraft lap joints play an important role in minimizing the operational cost of airlines. Hence, airlines pay more attention to these technologies to improve efficiency. Namely, a major time consuming and costly process is maintenance of aircraft between the flights, for instance, to detect early formation of cracks, monitoring crack growth, and fixing the corresponding parts with joints, if necessary. This work is focused on the study of repairs of cracked aluminium alloy (AA) 2024-T3 plates to regain their original strength; particularly, cracked AA 2024-T3 substrate plates repaired with doublers of AA 2024-T3 with two configurations (riveted and with adhesive bonding) are analysed. The fatigue life of the substrate plates with cracks of 1, 2, 5, 10 and 12.7mm is computed using Fracture Analysis 3D (FRANC3D) tool. The stress intensity factors for the repaired AA 2024-T3 plates are computed for different crack lengths and compared using commercial FEA tool ABAQUS. The results for the bonded repairs showed significantly lower stress intensity factors compared with the riveted repairs. This improves the overall fatigue life of the bonded joint.

  15. Evaluation of interfacial bonding in dissimilar materials of YSZ-alumina composites to 6061 aluminium alloy using friction welding

    Energy Technology Data Exchange (ETDEWEB)

    Uday, M.B., E-mail: ummb2008@gmail.com [School of Materials and Mineral Resources Engineering, Engineering Campus, Universiti Sains Malaysia, 14300 Nibong Tebal, Penang (Malaysia); Ahmad Fauzi, M.N., E-mail: afauzi@eng.usm.my [School of Materials and Mineral Resources Engineering, Engineering Campus, Universiti Sains Malaysia, 14300 Nibong Tebal, Penang (Malaysia); Zuhailawati, H.; Ismail, A.B. [School of Materials and Mineral Resources Engineering, Engineering Campus, Universiti Sains Malaysia, 14300 Nibong Tebal, Penang (Malaysia)

    2011-01-25

    Research highlights: {yields} Friction-welding process. {yields} Joining between ceramic composite and metal alloy. {yields} Slip casting of the yttria stabilized zirconia/alumina composite samples. - Abstract: The interfacial microstructures characteristics of alumina ceramic body reinforced with yttria stabilized zirconia (YSZ) was evaluated after friction welding to 6061 aluminum alloy using optical and electron microscopy. Alumina rods containing 25 and 50 wt% yttria stabilized zirconia were fabricated by slip casting in plaster of Paris (POP) molds and subsequently sintered at 1600 deg. C. On the other hand, aluminum rods were machine down to the required dimension using a lathe machine. The diameter of the ceramic and the metal rods was 16 mm. Rotational speeds for the friction welding were varied between 900 and 1800 rpm. The friction pressure was maintained at 7 MPa for a friction time of 30 s. Optical and scanning electron microscopy was used to analyze the microstructure of the resultant joints, particularly at the interface. The joints were also examined with EDX line (energy dispersive X-ray) in order to determine the phases formed during the welding. The mechanical properties of the friction welded YSZ-Al{sub 2}O{sub 3} composite to 6061 alloy were determined with a four-point bend test and Vickers microhardness. The experimental results showed the degree of deformation varied significantly for the 6061 Al alloy than the ceramic composite part. The mechanical strength of friction-welded ceramic composite/6061 Al alloy components were obviously affected by joining rotational speed selected which decreases in strength with increasing rotational speed.

  16. CONTROLLING ODOROUS EMISSIONS FROM IRON FOUNDRIES

    Science.gov (United States)

    The report discusses the control of odorous emissions from iron foundries. he main process sources of odors in iron foundries are mold and core making, casting, and sand shakeout. he odors are usually caused by chemicals, which may be present as binders and other additives to the...

  17. Health risk assessment of workers exposed to metals from an aluminium production plant.

    Science.gov (United States)

    Buranatrevedh, Surasak

    2010-12-01

    Foundry is an industry involved various kinds of metals and chemicals. Workers who work in foundry industry are at risk of exposure to these metals and chemicals. Objective of this study was to conduct quantitative health risk assessment for workers who exposed to metals from an aluminium production industry. The U.S. National Academy of Sciences' four steps of health risk assessment were used to conduct quantitative health risk assessment in this study. This study showed that there were 6 types of metals involved in the aluminium foundry in this study. These metals could cause various health effects but not cancers. Workers were mostly exposed to these metals by inhalation. Calculated reference dose (RfD) for inhalation of aluminium used in this assessment was 0.000015 mg/kg/day. Calculated RID for inhalation of manganese used in this assessment was 0.000002 mg/kg/day. Calculated RfD for inhalation of copper used in this assessment was 0.000028 mg/kg/day. Calculated RID for inhalation of zinc used in this assessment was 0.000083 mg/ kg/day. Calculated RID for inhalation of magnesium used in this assessment was 0.949833 mg/kg/day. Calculated RID for inhalation of iron used in this assessment was 10.6219 mg/kg/day. Maximum daily doses (MDDs) for workers who exposed to metals measured in this foundry were 0, 0, 0.000463, 0.0000927, 0.000162 and 0 mg/kg/day for manganese, zinc, aluminium, iron, magnesium and copper, respectively. Finally, risk characterization for workers exposed to metals in this aluminium foundry showed that workers in this foundry had 31 times higher risk of developing diseases from aluminium than persons who were not exposed to aluminium. These workers had the same risk of developing diseases from other metals and chemicals as persons who were not exposed to those metals and chemicals. Workers who exposed to aluminium in this aluminium production plant had 31 times risk of developing non-carcinogenic effects from aluminium compared with normal

  18. Plasma on a foundry cupola

    Science.gov (United States)

    Pineau, Didier

    An experiment of a plasma torch on a production foundry cupola is reported. The test runs were conducted on a hot blast cupola, the blast temperature in the absence of plasma being 400 C. With the torch, the temperature of the blast was increased to 1000 C. The experiment was conducted for the manufacture of car engines with a 2.5 MW transportable plasma system. The cupola was boosted with a 4 MW torch and results included an increase in production of 45 percent, a decrease in coke rate and no more new iron in the loads. The plasma torch and hot air cupola furnace are described.

  19. Synergy of the Plastic Treatment HPT and Shot Peening in Aluminium Alloy Al-Mg-Mn-Sc-Zr

    Directory of Open Access Journals (Sweden)

    Stegliński M.

    2016-06-01

    Full Text Available An improvement in fatigue strength is one of the main factors enabling the use of high-durability Al-Mg-Mn-Sc-Zr alloys in functional components of mobile robots. As part of this study, a computer simulation was carried out using ANSYS LS-DYNA software that involved the hybridization of high pressure torsion (HPT and shot peening (SP forming processes. The numerical analysis was aimed at determining residual stresses and strains that affect the durability and stress characteristics of the analyzed Al alloy. Results of the study indicate that tensile stresses of σ = 300 MPa generated as a result of HPT are transformed into a beneficial stress of σ = 25 MPa resulting from plastic strains caused by SP surface treatment.

  20. Impact properties of the aircraft cast aluminium alloy Al-7Si0.6Mg (A357

    Directory of Open Access Journals (Sweden)

    Alexopoulos N.D.

    2010-06-01

    Full Text Available The impact mechanical properties of the widely used in the aeronautics A357 cast aluminum alloy were investigated by exploiting experiments on an instrumented Charpy impact testing machine. The evaluated impact properties for 25 different artificial aging heat treatment conditions were analyzed and discussed in conjunction with the respective tensile properties. Correlations are proposed to establish useful relationships between impact resistance and tensile strain energy density properties. The established correlations, which are well supported by the performed experiments, can be used to estimate the tensile ductility and toughness of the A357 cast aluminum alloy from the Charpy impact test. Performed fractographic analyses were supporting the physically arbitrary correlation between tensile strain energy density and impact resistance.

  1. Impact properties of the aircraft cast aluminium alloy Al-7Si0.6Mg (A357)

    Science.gov (United States)

    Alexopoulos, N. D.

    2010-06-01

    The impact mechanical properties of the widely used in the aeronautics A357 cast aluminum alloy were investigated by exploiting experiments on an instrumented Charpy impact testing machine. The evaluated impact properties for 25 different artificial aging heat treatment conditions were analyzed and discussed in conjunction with the respective tensile properties. Correlations are proposed to establish useful relationships between impact resistance and tensile strain energy density properties. The established correlations, which are well supported by the performed experiments, can be used to estimate the tensile ductility and toughness of the A357 cast aluminum alloy from the Charpy impact test. Performed fractographic analyses were supporting the physically arbitrary correlation between tensile strain energy density and impact resistance.

  2. Fatigue FEM analysis in the case of brazed aluminium alloy 3L59 used in aeronautical industry

    Science.gov (United States)

    Dimitrescu, A.; Amza, Gh; Niţoi, D. F.; Amza, C. Gh; Apostolescu, Z.

    2016-08-01

    The use, on a larger scale, of brazed aluminum alloys in the aerospace industry led to the need for a detailed study of the assemblies behavior. These are built from 6061 aluminum aloy (3L59) brazed with aluminum aloy A103. Therefore, a finit element simulation (FEM) of durability is necessary, that consists in the observation of gradual deterioration until failure. These studies are required and are previous to the stage of the producing the assembly and test it by traditional methods.

  3. Investigation impact of stressed state conditions and thermomechanical parameters on the texture and structure evolution in 1565ph aluminium alloy

    Science.gov (United States)

    Yashin, V. V.; Aryshensky, E. V.; Kawalla, R. F.; Serebryany, V. N.; Rushchits, S. V.

    2016-11-01

    The paper is devoted to study of the impact stress condition and thermomechanical treatment parameters on the structure and texture evolution of new 1565 ph aluminum alloy. For that purposes, we use test on Gleeble equipment, FM calculation, optical microscopy and x ray diffraction texture analysis. The dependency between the deformation texture components development and strain rate value was established. Differences in the texture evolution at uniaxial compression stress and plain strain mode were revealed.

  4. Biochemical analysis of the Hormoconis resinae fungal mycelium in the corrosion of aeronautical aluminium alloys

    Directory of Open Access Journals (Sweden)

    Araya, R.

    2007-06-01

    Full Text Available Biochemical analyses of the Hormoconis resinae fungal mycelium would explain behaviour differences of corrosive and non-corrosive strains on Al and its aeronautical alloys. In previous works its aggressiveness had been studied through SEM-EDX surface analysis, electrochemical techniques and immersion testing. In this paper separation of the proteins of the mycelium produced by a non-corrosive strain and its culture along three generations was performed. Cultures were prepared in batch in the presence and absence of pure Al and AA 2024, AA 7005 and AA 7075 alloys. The mycelia grown throughout the three generations increasingly
    recovered usual characteristics at the third replication, included their corrosiveness on Al and its alloys previously shown by all our strains. Amongst the bio-molecule fractions isolated and analysed during this preliminary study only the proteins revealed changes with the generation grown. When this fungal strain was cultured in the presence of alloy metal sheets electrophoresis of the protean fraction was correlative with the distinct mycelia behaviour observed, including corrosiveness on Al and its alloys.

    Las diferencias entre el comportamiento corrosivo y no corrosivo de una cepa del hongo Hormoconis resinae sobre aluminio y sus aleaciones aeronáuticas se explicarían a través de análisis bioquímicos del micelio. En trabajos previos, el comportamiento corrosivo se estudió mediante análisis de superficie SEM-EDX, técnicas electroquímicas y ensayos de inmersión. En este trabajo, se llevó a cabo la separación de proteínas del micelio producido por una cepa que perdió su corrosividad y su cultivo a través de tres generaciones. Cultivos en batch, en presencia y ausencia de aluminio y sus aleaciones AA 2024, AA 7005 y AA 7075, a través de tres generaciones del micelio crecido, fueron recuperando sus características, incluida su habitual corrosividad, en la tercera replicaci

  5. Application of glass ellipsoid aluminium alloy structure in building engineering%玻璃椭球体铝合金结构在建筑工程中的应用

    Institute of Scientific and Technical Information of China (English)

    吴志平; 朱伟信; 赵华; 蒋乃杰; 魏国华

    2001-01-01

    The aluminium and titanium are used as mesh shell construction of ellipsoid glass building with major axis length of 66.8 m, minor axis length of 57.0 m, above ground 34.3 m, under ground 7.25 m. The weight of glass as building covering outside is 400 t. The aluminium alloy H beam, aluminium round gusset and stainless steel lock bolts are used for construction to form single layer aluminium mesh shell system. This engineering structure stressing is complicated. The requirements for component fabrication are very strict with bigger difficulty during construction and installation. This is a first large aluminium structure ellipsoid engineering in China. The plan selection, structure design, material selection and ellipsoid engineering construction and installation for this building were presented in the paper.%以铝钛合金为网壳结构的玻璃椭球体建筑,长轴为 66.8 m,短轴为 57.0 m,地面以上 34.3 m,地下 7.25 m高。该建筑外覆玻璃盖层重达 400 t,结构采用铝合金工字梁、铝质圆形节点板与不锈钢锁紧螺栓,构成单层铝网壳体系。工程结构受力复杂,构件制作要求严格,施工安装难度较大,是我国首例铝结构大型椭球形工程。文中对该建筑工程从方案选定、结构设计、材料选用及球体工程施工安装等作了较详细介绍。

  6. Health and safety at work in foundry companies

    Directory of Open Access Journals (Sweden)

    L. Wojtynek

    2011-07-01

    Full Text Available The article presents the identification and analysis of threats in the environment of the foundry at individual stages of the casts manufacturing process. A generalized model of the foundry was created in the system presentation including harmful and dangerous factors in the foundry technical workplace. This model can refer to an iron foundry and cast steel and small non-ferrous foundries, to modern foundries, with automatic moulding lines and to chill and pressure foundries where machines execute the majority of essential operations.

  7. A Study Into Effects of Different Parameters on Mechanical Properties in Friction Stir Welding of AA 2024 Aluminium Alloy

    Directory of Open Access Journals (Sweden)

    Aydın ŞIK

    2010-02-01

    Full Text Available In this study AA2024 alloy, which is used especially in aircraft body, wings and automotive industry due to its lightness, workable aspect, high corrosion resistance and durability, was welded with stir friction method, and fatigue, hardness, bending and tension experiments of the joints obtained were conducted. Welding progress speed of the 4 mm thick sheets and stir tool rotation were determined to be the variable parameters. These parameters were taken as 20 mm shoulder width, 1000 rpm traverse speed, 1500 rpm, 2500 rpm and the progress speed was taken as 120 mm/min and 200 mm/min.

  8. Evolution of the microstructure, texture and creep properties of the 7075 aluminium alloy during hot accumulative roll bonding

    OpenAIRE

    Hidalgo-Manrique, P.; Cepeda-Jiménez, C.M.; Orozco-Caballero, Alberto; Ruano, Oscar Antonio; Carreño, Fernando

    2014-01-01

    The 7075 Al alloy was severely deformed at 350 °C by a 3:1 thickness reduction per pass accumulative roll bonding (ARB) process up to six passes. It was found that discontinuous recrystallisation occurs during the inter-pass annealing stages from the third pass on, attributable to the increment of the mean particle size during processing. As a consequence, the mean crystallite size did not decrease, but remained approximately constant at 440 nm along the present ARB process and the mean bound...

  9. Experimental Study of the Micro-Arc Oxide Coating Effect on Thermal Properties of an Aluminium Alloy Piston Head

    Directory of Open Access Journals (Sweden)

    N.Yu. Dudareva

    2015-09-01

    Full Text Available The purpose of the present study is to investigate the influence of differently sized microarc oxidation coatings, applied to the bottom of pistons made with an Al-12Si-Mg-Cu-Ni alloy, on its thermal properties by simulating the operation of a real engine. This study is based on the premise that the alumina coating thickness affects the heat transfer and temperature distribution in the piston. The analysis of thermal properties of pistons and suggestions for the optimal thermal barrier coating thickness are presented.

  10. Circular economy: To be or not to be in a closed product loop? A Life Cycle Assessment of aluminium cans with inclusion of alloying elements

    DEFF Research Database (Denmark)

    Niero, Monia; Olsen, Stig Irving

    2016-01-01

    to a temporal interval of five years. Different aluminium packaging scrap sources were considered: mixed packaging aluminium scrap and used beverage can scrap. The outcomes of the mass balance were used to quantify the amount of Mn and primary Al that needs to be reintegrated in each scenario according...

  11. 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.

  12. Residual stresses, defects and fatigue cycling in friction stir butt welds in 5383-H321 and 5083-H321 aluminium alloys

    Energy Technology Data Exchange (ETDEWEB)

    James, M.N.; Bradley, G.R. [Mechanical and Marine Engineering, Univ. of Plymouth, Plymouth (United Kingdom); Hattingh, D.G. [Mechanical Engineering, PE Technikon, Port Elizabeth (South Africa); Hughes, D.J.; Webster, P.J. [FaME38, ILL-ESRF, Grenoble (France)

    2003-07-01

    This paper presents results from a substantial investigation of residual stresses and defects associated with single pass and double pass friction stir welds in 5083-H321 and 5383-H321 aluminium alloys. The residual stress part of the paper summarises data on their as-welded magnitude and plate-to-plate variation, together with their modification during applied bending fatigue loading corresponding to cyclic lives of 10{sup 5} and 10{sup 7} cycles. Results indicate fairly low initial peak tensile stresses both parallel with, and perpendicular to, the weld run. Peak tensile stresses occur just outside the tool shoulder with values typically in the range 0-30 MPa. Peak compressive stresses have much higher magnitudes (typically in the range -50 MPa to -140 MPa) and occur at distances of up to 40 mm from the weld centreline. Significant plate-to-plate variability in residual stress magnitudes exists, and fatigue cycling can raise peak tensile stresses by as much as a factor of four (to around 80 MPa). This has significant potential influence on fatigue life prediction. The paper also presents data on the occurrence of partial-fusion defects (PFD's or so-called 'kissing bonds' or 'onion-skin' defects) as a function of tool travel speed (in the range 80-200 mm/min), and their influence on fatigue life. Results indicate that PFD's can sometimes be associated with crack initiation, but that their major effect is more likely to appear when levels of plastic deformation are high, i.e. during relatively fast fatigue crack growth or during fast fracture. (orig.)

  13. The ‘full sleeve’ application in the horizontal cold-chamber machine for pressure die casting of aluminium alloys

    Directory of Open Access Journals (Sweden)

    Z. Konopka

    2008-04-01

    Full Text Available The ‘full sleeve’ construction has been designed and accomplished in the horizontal cold-chamber pressure die casting machine. Main part of this solution is a counter plunger placed in a movable die half which allows for full filling of the shot sleeve and precisely fixes the metal quantity needed for casting. The purpose of this new construction solution is mainly the reduction of the casting porosity caused by air entrapment and the improvement of both castability and accuracy of the die cavity reproduction. For such a redesigned machine there have been performed examinations consisting in pressure casting of AlSi9Cu alloy (EN AC-46000 at varying plunger velocity in the second stage of injection and varying intensification pressure. The alloy castability (the die filling ability has been measured for each parameter setting. For the purpose of comparison, similar measurements have been performed also for the conventional system without a counter plunger. The castability examination has been done by means of a specially designed die with an impression of a trial casting of variable wall thickness. The experiments have been held according to the assumed factor design 22, what allowed for determining the mathematical models describing the influence of die filling parameters on the castability and the die cavity reproduction level. Both alternatives of the experiment confirmed the positive influence of plunger velocity and intensification pressure increase on the improvement of castability, the measure of the latter being the filled length of the impression. Applying of the new ‘full sleeve’ solution has improved castability for each experiment by about 20% as compared with conventional alternative. Castability in the ‘full sleeve’ system has been increased even for low values of plunger velocity and intensification pressure. For both alternative systems the influence of plunger velocity has been found, as an average, by four times

  14. Fatigue Property of Friction Stir Welded Extruded Aluminium Alloy 6005A%6005A铝合金型材搅拌摩擦焊接头疲劳性能研究

    Institute of Scientific and Technical Information of China (English)

    陈荣康; 孙春方; 戴瑛

    2012-01-01

    A friction stir welded(FSW) butted aluminium alloy 6005A plate, which is used for train wall sides, was tested under static tensile and fatigue tensile loads. Due to effect of FSW, its static and fatigue strength are lower as compare that with parent material. Full-scale static tensile, fatigue tensile and 3-points bending fatigue test were completed on friction stir welded extruded aluminium alloy 6005A. The fatigue behaviors of tensile and bending characterised by S-N curve with a stress ratio of 0.1 were obtained by least square method. The fatigue limits of friction stir welded extruded aluminium alloy 6005A subjected to tensile and bending loading were experimentally established. Furthermore, failure location of such structure under fatigue loading proofs the strength of FSW butt joint. The presented test data provides solid base for design and practical application of the friction stir welded extruded aluminium alloy 6005A.%对车身用6005A铝合金FSW对接板材进行了拉伸性能、拉伸疲劳性能试验研究,并与母材进行了对比;对6005A铝合金FSW对接型材进行了拉伸性能、拉伸疲劳性能和三点弯曲疲劳性能试验研究;根据疲劳试验结果,拟合出6005A铝合金FSW对接板材、型材的拉伸、三点弯曲的S-N曲线(R=0.1),并由此得出该结构的疲劳强度;由6005A铝合金FSW对接型材的静拉伸、疲劳拉伸和三点弯曲疲劳载荷作用下的失效位置,证实了FSW接头的可靠性,为结构的设计和使用提供了可靠的试验数据支持.

  15. Modeling and Simulation of Laser Welding for Aluminium Alloy%激光焊接铝合金材料过程的建模与仿真

    Institute of Scientific and Technical Information of China (English)

    卢艳; 张静; 胡敬佩; 项俊锋

    2012-01-01

    The distribution of the temperature field during laser welding based on aluminium alloy 3A21 was dynamically simulated by FEA software-ANSYS. In view of the highly non-linear characters of laser welding, a travel heat source combining with the body loads was built by analyzing the thermal physical parameters of material, such as latent heat of fusion, thermal conduction,convection and radiation. The results show that the temperature gradient of laser welding is larger, and HAZ is smaller than others. The temperature curves in the temperature fields rise and decline exponential], and the temperature in weld and near weld changes rapidly. The simulation results of width in the weld is in line with the experimental results, which verify the applicability of the model established by moving heat source during the laser welding based on aluminum alloy sheet applying to the temperature field simulation, and to a certain extent, the forming mechanism of the laser welding is revealed.%在试验基础上,利用有限元软件ANSYS对3A21铝合金材料激光焊接温度场进行了动态模拟.通过对激光焊接非线性瞬态过程的分析,分析与温度场有关的潜热、热传导、对流、辐射等材料热物理属性,建立了激光焊接的移动热源模型.仿真结果表明:激光焊接薄板铝合金的温度场梯度大,热影响区小;温度场中各点温度呈指数式升高和衰减;焊缝和近焊缝区温度升降急剧,焊缝宽度的仿真结果与试验结果相一致,从而验证了所建立的移动热源模型在激光焊接铝合金薄板温度场模拟中的适用性,在一定程度上揭示了激光焊接的成型机理.

  16. Microstructure and Properties of Welded Joint of Extruded 6005A Aluminium Alloy%6005A铝合金型材焊接接头组织与性能

    Institute of Scientific and Technical Information of China (English)

    尹志民; 张爱琼; 王炎金

    2001-01-01

    采用国产6005A铝合金进行焊接试验,并对焊接接头进行了力学性能检测及金相显微组织观察。结果表明,6005A铝合金的焊接接头焊缝两侧离焊缝中心约10~15mm的地方存在一对对称分布的软化区,其原因是由于焊接热的影响使该部位发生了过时效.对进口的6005A大型多孔铝型材焊接接头进行分析,发现焊接接头上软化区硬度降低的程度明显较小,这是由于实际的多孔型材在该部位设置有加强筋,加强筋有显著的散热作用,降低了焊接过程中该部位的温升.另一方面,加强筋增大了软化区的承载面积,有机械补强作用。%Welding test of extruded 6005A Aluminium alloy was performed and mechanical properties and optical microstructures were studied. The results show that there is a pair of symmetric soft zone which was located on both sides of the weld about 10~15 mm apart from the weld center. The occurrence of soft zone is due to overaging caused by heat input during welding. In the condition of big practical extruded 6005A alloy welded joint, the softing degree of mentioned above soft zone obviously decreases, attributed to that there is a reinforce rib which have obvious heat scatting action, and then decreases the temperature increasing during welding. On another hand, this reinforce rib increase the loading area and have a strength compensating.

  17. Comparison between diffraction contrast tomography and high-energy diffraction microscopy on a slightly deformed aluminium alloy.

    Science.gov (United States)

    Renversade, Loïc; Quey, Romain; Ludwig, Wolfgang; Menasche, David; Maddali, Siddharth; Suter, Robert M; Borbély, András

    2016-01-01

    The grain structure of an Al-0.3 wt%Mn alloy deformed to 1% strain was reconstructed using diffraction contrast tomography (DCT) and high-energy diffraction microscopy (HEDM). 14 equally spaced HEDM layers were acquired and their exact location within the DCT volume was determined using a generic algorithm minimizing a function of the local disorientations between the two data sets. The microstructures were then compared in terms of the mean crystal orientations and shapes of the grains. The comparison shows that DCT can detect subgrain boundaries with disorientations as low as 1° and that HEDM and DCT grain boundaries are on average 4 µm apart from each other. The results are important for studies targeting the determination of grain volume. For the case of a polycrystal with an average grain size of about 100 µm, a relative deviation of about ≤10% was found between the two techniques.

  18. Effect of tool shape and welding parameters on mechanical properties and microstructure of dissimilar friction stir welded aluminium alloys

    Directory of Open Access Journals (Sweden)

    Chetan Aneja

    2016-07-01

    Full Text Available In the present experimental study, dissimilar aluminum alloy AA5083 and AA6082 were friction stir welded by varying tool shape, welding speed and rotary speed of the tool in order to investigate the effect of varying tool shape and welding parameters on the mechanical properties as well as microstructure. The friction stir welding (FSW process parameters have great influence on heat input per unit length of weld. The outcomes of experimental study prove that mechanical properties increases with decreasing welding speed. Furthermore mechanical properties were also found to improve as the rotary speed increases and the same phenomenon was found to happen while using straight cylindrical threaded pin profile tool. The microstructure of the dissimilar joints revealed that at low welding speeds, the improved material mixing was observed. The similar phenomenon was found to happen at higher rotational speeds using straight cylindrical threaded tool.

  19. Comparison between diffraction contrast tomography and high-energy diffraction microscopy on a slightly deformed aluminium alloy

    Directory of Open Access Journals (Sweden)

    Loïc Renversade

    2016-01-01

    Full Text Available The grain structure of an Al–0.3 wt%Mn alloy deformed to 1% strain was reconstructed using diffraction contrast tomography (DCT and high-energy diffraction microscopy (HEDM. 14 equally spaced HEDM layers were acquired and their exact location within the DCT volume was determined using a generic algorithm minimizing a function of the local disorientations between the two data sets. The microstructures were then compared in terms of the mean crystal orientations and shapes of the grains. The comparison shows that DCT can detect subgrain boundaries with disorientations as low as 1° and that HEDM and DCT grain boundaries are on average 4 µm apart from each other. The results are important for studies targeting the determination of grain volume. For the case of a polycrystal with an average grain size of about 100 µm, a relative deviation of about ≤10% was found between the two techniques.

  20. Studies on the Executionof Models Used in Iron Foundry From Epoxidic Resins

    Directory of Open Access Journals (Sweden)

    Cinca - Ionel Lupinca

    2006-10-01

    Full Text Available The epoxidic resins are materials frequently used in the execution of the models used in iron foundry. This materials can replace casily wood or aluminium in the execution of the models needed in series productions, having better resistance properties and the high dimensional precision. The properties of these resins are obtained from the completion of the epoxibifunctional molecules with supplements. This paper establishes the result of mixing the two components, as well as the supplements used to improve the mechanic and the technological properties.