论文部分内容阅读
采用喷射共沉积工艺制备了6066Al基体铝合金以及含不同体积分数增强颗粒的6066Al/SiCp铝基复合材料,与常规熔铸+挤压的基体铝合金比较,喷射共沉积基体铝合金和复合材料的力学性能峰值时效时间明显缩短,即喷射共沉积6066Al和6066Al/SiCp颗粒增强铝基复合材料发生加速时效现象。对材料的微观组织进行常规金相和透射电镜观察,分析了SiCp增强陶瓷颗粒以及喷射共沉积工艺对材料时效析出行为的影响。研究表明:喷射共沉积工艺所形成的非平衡组织中溶质原子浓度高,时效析出驱动力大,有利于时效过程溶质原子扩散和第二相的形核。喷射共沉积材料细化的晶粒组织及复合材料中的高密度位错有利于非均匀形核,是加速材料时效析出动力学过程的主要原因。
6066Al matrix aluminum alloy and 6066Al / SiCp aluminum matrix composites with different volume fraction enhancement particles were prepared by spray co-deposition process. Compared with the conventional aluminum alloy with melt-casting and extrusion, the mechanical properties of spray-deposited matrix aluminum alloy and composite Performance peak aging time was significantly shortened, that is spray co-deposition 6066Al and 6066Al / SiCp particle reinforced aluminum matrix composites accelerated aging phenomenon. The microstructure of the material was observed by conventional metallurgical and transmission electron microscopy. The effects of SiCp reinforced ceramic particles and spray co-deposition on the aging behavior of the material were analyzed. The results show that the concentration of solute atoms in the non-equilibrium structure formed by jet co-deposition process is high, and the driving force for precipitation is large, which is in favor of the diffusion of solute atoms and the nucleation of the second phase during the aging process. Jet co-deposition material refinement of the grain structure and high density of dislocations in the composite material is conducive to heterogeneous nucleation, accelerating the material aging precipitation kinetics of the main reasons.