纳米Al_2O_(3p)Cu复合材料的再结晶微观结构分析

Microstructure Analysis of Nano-Al_2O_(3p)/Cu Composite in Process of Recrystallization Annealing

针对传统高导电材料的抗软化温度较低的不足,研究开发了高软化温度的纳米Al2O3颗粒增强Cu基复合材料。测试了Al2O3pCu复合材料的退火温度硬度关系曲线,采用扫描电子显微镜、透射电子显微镜和能谱仪分析了其再结晶过程的微观组织结构变化规律。结果表明,Al2O3pCu复合材料具有很高的再结晶软化抗力,退火温度超过900℃再结晶过程才明显进行;其晶粒直径在0.5～5μm之间,αAl2O3质点直径在10～20nm之间,且主要分布在亚晶界上;探讨了Al2O3pCu复合材料再结晶形核机制和纳米氧化铝质点对再结晶核心长大的影响。

To replace the conventional materials with poor soften resistance, a novel Al2O3p/Cu composite with high softening resistance by means of internal oxidation method were fabricated. The softening temperature of the Al2O3p/Cu composite was determined by annealing tests at the temperature varying from room temperature to 1050°C. The evolution of microstructure of the composite in the process of recrystallization annealing were investigated by means of SEM, TEM and EDS. The results show that the Cu-0.6% Al2O3 composite presents excellent recrystallization resistance. The recrystallization process doesn't occur until the annealing temperature exceeds 900°C. The grain size of the composite is 0.5-5 μm in diameter, while the size of alumina particulates produced by the internal oxidation process are about 10-20 nm in diameter. The nano-Al2O3 is mainly distributed on the sub-grain boundary. The nucleation mechanism of the recrystallization of the Al2O3p/Cu composite is that the subgrain dislocation boundaries disappear to form the boundaries of the new small grain without lattice disorder. The effect of the nano-Al2O3 on the growth of recrystallization nuclei is also discussed.