高能球磨制备Al-Pb-Si-Sn-Cu纳米晶粉末的特性

通过机械合金化制备了Al-15％Pb-4％Si-1％Sn-1．5％Cu(质量分数)纳米晶粉末。采用X射线衍射(XRD)，扫描电镜(SEM)和透射电镜(TEM)对不同球磨时间的混合粉末的组织结构、晶粒大小、微观形貌以及颗粒中化学成分分布情况进行了研究。结果表明混合粉末经过球磨后形成了纳米晶，其组织非常均匀。球磨对Pb的作用效果明显大于对Al的作用效果，经过40h球磨后Pb粒子达到40nm，而Al在球磨60h后晶粒为65nm；经球磨后，Cu和Si固溶于Al的晶格中，而Sn则固溶于Pb晶格中，并且Al和Pb发生了互溶，形成了Pb(Al）超饱和固溶体；在球磨过程中硬度高的脆性粒子Si难于完全实现合金化。

Synthesized by Ball Milling Al-Pb-Si-Sn-Cu Nanocrystalline Powder

The nanocrystalline powder of Al-15%Pb-4%Si-1%Sn-1.5%Cu (mass%) were prepared by mechanical alloying. Systematical investigations were carried out on the structural change, grain size, lattice constant, morphology of the powder and the chemical composition of the Al-15%Pb-4%Si-1%Sn-1.5%Cu high energy ball milled powder using X-ray diffraction (XRD), transmission electron microscopy (TEM) and scanning electron microscopy(SEM). The experimental results showed that the nanocrystalline powders were synthesized and the homogenous nanophases was achieved by mechanical alloying. The effect of ball milling was more evident to lead than to aluminum. The grain size of Pb was 40 nm after milling for 40 h, and the grain size of aluminum was 65 nm after milling for 60 h. The solid solutions of Al(Cu, Si) and Pb(Sn), and supersaturated solid solution of Pb(Al) were observed by MA. Otherwise, brittle element powder of silicon was more difficulty alloying in the mechanical alloying process.