中国有色金属学报(英文版)
Transactions of Nonferrous Metals Society of China
| Vol. 14 No. 1 February 2004 |
（1.State Key Laboratory of Solidification Processing,
Northwestern Polytechnical University, Xi an 710072, China;
2. Department of Mechanical and Electrical Engineering, Zhengzhou Institute of Technology,
Zhengzhou 450052, China）
Abstract:Cu-Cr composites were prepared by self-made directional solidification equipment with the high temperature gradient and double-zone heating. The microstructural evolution was investigated during the directional solidification with the different solidification rate for Cu-1.0%Cr, Cu-1.7%Cr and Cu-5.6%Cr alloys, respectively. It is shown that for the hypoeutectic Cu-1.0%Cr alloy, the general microstructures consist of primaryα(Cu) phase and the rod-like or needle-like (α+β) eutectics, and for the hypereutectic Cu-1.7%Cr and Cu-5.6%Cr alloys,α(Cu) phase, primaryβ(Cr) phase and (α+β) eutectics coexist. With the increase of the solidification rate, the morphology evolution of every phase is that, 1st cellular(dendrite) ofα(Cu) phase thins and cellular(dendrite) spacing shortens gradually, (α+β) eutectics set inα(Cu) cellular or dendrite, and primaryβ(Cr) phase distributes unevenly onα(Cu) matrix, whose morphology undergoes the change from dendrite to particle
Key words: directional solidification; Cu-Cr alloy; composite
