AlCoNi十次准晶与金属铜间扩散机制分析

摘要

Diffusion behavior between Al72 Co20 Ni8 quasicrystalline particles and Cu was investigated by powder metallurgy. Experimental results showed that Cu atoms diffuse along two directions within quasi-crystal particles. After different heat treatment, Al72Co20Ni8 decagonal quasicrystal transformed into lamellae of the Al(Co,Ni)x transitional crystal phase, and then decomposed into Al-Co phase.%本文利用扫描电镜和透射电镜分析了粉末冶金法制备的Al72Co20 Ni8十次准晶颗粒与Cu基体之间的扩散行为与反应机制.研究发现700℃下,Cu原子沿两个方向扩散进入准晶颗粒,一是沿着准晶晶粒的晶界,二是垂直于准晶周期轴方向扩散进入其晶粒内部.Al72 Co20 Ni8准晶由于Al原子向外扩散先转变为片层状Al(Co,Ni)x过渡晶体相,最终生成为Al-Co相.Al72 Co20 Ni8准晶颗粒中的Al原子过饱和固溶到基体Cu之中,冷却后析出Cu-Al相.