深冷处理对Cu40Zr44Ag8Al8非晶复合材料组织和力学性能的影响

研究了深冷处理对Cu40Zr44Ag8Al8非晶复合材料组织演变和力学性能的影响.运用光学金相、X射线衍射分析（XRD）、差示扫描量热分析（DSC）和显微硬度等实验手段,对Cu40Zr44Ag8Al8非晶复合材料深冷处理前后的非晶结构和晶化相进行测试分析.结果表明：深冷处理2h,Cu40Zr44Ag8Al8非晶复合材料的第二相体积份数增多.随着深冷处理时间增加到24h,第二相的体积份数和尺寸进一步增多,同时非晶复合材料的显微硬度也有一定的提高.XRD分析表明Cu40Zr44Ag8Al8非晶复合材料中形成了Cu10Zr7相和AgZr相.非晶复合材料非晶基体的玻璃转变温度Tg随着深冷处理时间的增加而提高,晶化潜热则随着深冷时间的增加而降低.Cu40Zr44Ag8Al8非晶复合材料组织结构的演变与深冷处理过程产生的内应力有关.

Effect of cryogenic treatment on microstructure and mechanical properties of Cu40Zr44Ag8Al8 bulk metallic glass composite

The effect of cryogenic treatment on microstructure and mechanical properties of Cu40Zr44Ag8Al8 bulk metallic glass composite（BMGC） has been investigated.The microstructure and mechanical properties of BMGC before and after cryogenic treatment were characterized through optical micrograph（OM）,X-ray diffraction（XRD）,differential scanning calorimetry（DSC） and Vickers micro hardness（Hv）.The results show that the formation of crystalline phase of Cu40Zr44Ag8Al8 BMGC can be obtained through the cryogenic treatment with 2 h.The dimension and volume fraction of crystalline phase increases with increasing of the cryogenic treatment duration from 2h to 24 h,which result in the improvement of micro hardness of BMGC.The Cu10Zr7 and AgZr phases were formed in Cu40Zr44Ag8Al8 BMGC after cryogenic treatment.The glass transition temperature of amorphous matrix of BMGC increases with the increase of cryogenic treatment duration.However,the crystallization exothermal heat of BMG decreases with the increasing of the cryogenic treatment duration.The internal stress induced by cryogenic treatment was associated with the microstructure evolution of Cu40Zr44Ag8Al8 BMGC.