(1. 西安理工大学 材料科学与工程学院,西安 710048;
2. 上海理工大学 电功能材料研究所,上海 200093;
3. 河南科技大学 材料科学与工程学院,洛阳 471003)
摘 要: 研究不同温度时大变形Cu-15Cr-0.1Zr原位复合材料中Cr纤维的热稳定性,采用扫描电镜和透射电镜观察Cr纤维形态变化,测定Cr纤维的断开直径,并进行数值模拟。并根据模界面分裂模型计算了550~900 ℃时Cr在Cu/Cr界面的界面扩散系数。结果表明:高温条件下纤维的形态由片状到球体化断裂,其过程为,Cr纤维逐步形成空洞、纵向开裂、断开和球化;高温条件下纤维断裂受界面扩散控制。
关键字: Cu-Cr材料;原位复合材料;纤维;界面扩散;热稳定性
(1. School of Materials Science and Engineering, Xi’an University of Technology, Xi’an 710048, China;
2. Institute of Electric Functional Materials, University of Shanghai for Science and Technology,
Shanghai 200093, China;
3. School of Materials Science and Engineering, Henan University of Science and Technology,
Luoyang 471003, China)
Abstract: The thermal stability of Cr filaments in heavily drawn Cu-15Cr-0.1Zr in-situ composite wires was investigated at different temperatures. The shape changes of Cr filaments during annealing were observed by SEM and TEM, the break-up diameters of Cr filaments were determined and simulated. The interface diffusion coefficient of Cr on the Cu/Cr interface at 550−900 ℃ was calculated in terms of the boundary splitting models. The results of SEM and TEM show that the transition of Cr filaments from a platelike to a spherical microstructure of Cr filaments at elevated-temperature is as follows: cavitation, longitudinal splitting plus, cylinderization plus, breakup to complete spheroidization failure. The simulating result shows that the fracture behavior of the Cr filaments are controlled by a type of interfacial diffusion at elevated-temperature.
Key words: Cu-Cr materials; in-situ composite; filament; interfacial diffusion; thermal stability