Study of Preparation and Microstructure of Cu40Ni40Cr20 Alloys with Different Grain Size
CAO Zhong-qiu1,2, NIU Yan1, WANG Chong-lin1, WU Wei-tao1
1. State Key Laboratory for Corrosion and Protection, Institute of Metal Research, Shenyang,110016, China; 2. Department of Chemistry, Shenyang Normal University, Shenyang 110034, China
Abstract:The Cu40Ni40Cr20 bulk alloys with much different grain size have been prepared respectively by conventional arc-melting (CA) and mechanical alloying (MA) . Their micro-structural characteristics were investigated by X-ray diffraction (XDR), scanning electron microscopy(SEM) and energy-dispersive X-ray microanalysis (EDX). The results show that the microstructure of CA Cu40Ni40Cr20 is composed of double phases but extremely not uniform, while that of MA Cu40Ni40Cr20 is also composed of double phases but uniform with excellent density. With increase of ball milling time, the X-ray diffraction peaks have a deviation and become wide because of fine grain size and internal stress whereas the solid solubility of Cu in Cr and Cr in Cu increased evidently. When powders are milled for 60h, the alloyed powers have become single solid solution. Because the mechanically alloyed powders are in non-equilibrium state, the solute super-saturation decompose slowly with hot pressing and annealing in vacuum and finally the alloys transformed double-phases from single phase solid solution. The sizes of the two phases particles increased but still remained nano-size range. The lattices of copper, nickel and chromium do not produce distortion in the course of mechanical alloying, hot pressing mechanically alloyed powders and annealing. The effect of grain size on alloys microstructure was discussed in detail.
曹中秋, 牛焱, 王崇琳, 吴维(山文). 不同晶粒尺寸的三元Cu40Ni40Cr20合金的制备及其显微组织研究[J]. 材料工程, 2004, 0(11): 18-21,27.
CAO Zhong-qiu, NIU Yan, WANG Chong-lin, WU Wei-tao. Study of Preparation and Microstructure of Cu40Ni40Cr20 Alloys with Different Grain Size. Journal of Materials Engineering, 2004, 0(11): 18-21,27.
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