Microstructural evolution during reactive spray forming of dispersion strengthened Cu alloy

Six kinds of Al-Zn-Mg-Cu alloys, modified with nickel and zirconium, have been produced by rapid solidification using spray deposition(the Osprey process). The effect of nickel on the structures, mechanical properties of ultrahigh strength aluminium alloy is studied, and the probable maximum of mechanical properties is predicted. There are three nickel-rich phases, Al3Ni2, Al7Cu4Ni and MgNi2, forming in 1%Ni alloy, its ultimate tensile strength(UTS) increased with increasing extrusion ratios significantly while maintaining high levels of ductility, Futhermore, the extruded bars show enhancing more clearly than extruded plates in UTS and ductility. The content of Ni should decreased with increasing of Zn and Zr, and the highest properties(UTS=832MPa, Elongation=7.5%)are attained in 0.20Zr＋0.30Ni (wt%)alloy. In addition, the size, the shape and the homogeneous distribution of zirconium-rich phase produced in solidification is the key to effecting the mechanical properties of materials when Zr content is 0.2~0.5％.

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The effect of Al2Cu precipitates on the microstructural evolution, tensile strength, ductility and work-hardening behaviour of a Al–4wt.% Cu alloy processed by equal-channel angular pressing

Acta Materialia ◽

10.1016/j.actamat.2012.09.038 ◽

2013 ◽

Vol 61 (1) ◽

pp. 115-125 ◽

Cited By ~ 30

Author(s):

Erika F. Prados ◽

Vitor L. Sordi ◽

Maurizio Ferrante

Keyword(s):

Tensile Strength ◽

Equal Channel Angular Pressing ◽

Microstructural Evolution ◽

Work Hardening ◽

Angular Pressing ◽

Cu Alloy

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In Situ Observation of Diffusion Behavior and Microstructural Evolution on Interfaces in Al/Cu Bimetal

Materials Science Forum ◽

10.4028/www.scientific.net/msf.898.1020 ◽

2017 ◽

Vol 898 ◽

pp. 1020-1025

Author(s):

Fei Cao ◽

Fen Fen Yang ◽

Xue Jian Wang ◽

Hui Jun Kang ◽

Ya Nan Fu ◽

...

Keyword(s):

Transition Zone ◽

Microstructural Evolution ◽

Equilibrium Phase ◽

Liquidus Line ◽

Eutectic Growth ◽

Equilibrium Phase Diagram ◽

Eutectic Structure ◽

Diffusion Behavior ◽

Cu Alloy

Synchrotron X-ray radiography was used to in situ study the diffusion behavior and microstructural evolution of Al/Cu bimetal. The interface diffusion, dendritic/eutectic growth and the formation of intermetallic compounds around the Al/Cu bimetal interface were analyzed. During the isothermal diffusion process, a liquefied transition zone at the interface with a concentration gradient was formed when the Cu concentration exceeded eutectic composition of Al-Cu alloy. During the solidification of transition zone, the growth sequence of α-Al dendrites and eutectic structure were mainly dominated by the variation of Cu concentration and thermal field according to the temperature of the liquidus line of the equilibrium phase diagram. Finally, the transition zone around the interface were identified to be I (α-Al), II (Al+Al2Cu), III (Al2Cu) and IV (Al2Cu, AlCu and Al4Cu9), respectively.

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Investigation of microstructural evolution and mechanical properties during two-step ageing treatment at 115 and 160 °C in an Al–Zn–Mg–Cu alloy pre-stretched thick plate

Materials Characterization ◽

10.1016/j.matchar.2007.01.006 ◽

2008 ◽

Vol 59 (3) ◽

pp. 278-282 ◽

Cited By ~ 40

Author(s):

Zhihui Li ◽

Baiqing Xiong ◽

Yongan Zhang ◽

Baohong Zhu ◽

Feng Wang ◽

...

Keyword(s):

Mechanical Properties ◽

Microstructural Evolution ◽

Thick Plate ◽

Ageing Treatment ◽

Cu Alloy

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Modelling and Experiments Concerning Dendrite Re-Melting and Its Role in Microstructural Evolution in Spray Formed Ni Superalloys

Materials Science Forum ◽

10.4028/www.scientific.net/msf.654-656.1363 ◽

2010 ◽

Vol 654-656 ◽

pp. 1363-1366 ◽

Cited By ~ 1

Author(s):

Yong Zhang ◽

Z. Guo ◽

Guo Qing Zhang ◽

Jia Wei Mi ◽

Patrick S. Grant

Keyword(s):

Thermal Shock ◽

Microstructural Evolution ◽

Large Diameter ◽

Liquid Mixtures ◽

Spray Forming ◽

Solid Particles ◽

Fragmentation Behavior ◽

Dendrite Fragmentation ◽

Modelling Studies ◽

Gleeble 3500

This paper presents a combined experimental and modelling approach to understand dendrite fragmentation of atomised metal alloy droplets during deposition in spray forming, and to study quantitatively the relationship between this dendrite fragmentation behavior and subsequent microstructural evolution. A Gleeble 3500 physical simulator was used to create controlled thermal shock conditions in solid-liquid mixtures of Ni superalloy IN718 atomised powders, which simulated the environment of droplet deposition during the twin-atomiser spray forming of large diameter IN718 alloy billets at BIAM. The experiments were complemented by phase field modelling studies at Oxford. Experiment and modelling supported the hypothesis that the characteristic equiaxed spray formed microstructure depends critically upon the rapid remelting and thermal shock of fine-scale dendrites in solid particles in the spray to provide a high density of embryonic grains.

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