摘要
通过对Al-Pb混合粉进行不同时间的机械球磨,采用扫描电镜、电子探针对混合粉颗粒的形貌和组织结构进行了观察,并测试了球磨粉末的显微硬度和致密性能,结果表明:在机械球磨过程中,Al、Pb混合粉的颗粒尺寸初期增大,随后逐渐减小,最后趋于稳定;Al、Pb混合粉形成了层片状的复合粉,随球磨时间延长,层片变薄,最后层片组织断裂为细小弥散的颗粒;随球磨时间延长,Al-Pb复合粉的硬度增大,压制密度降低。最后将球磨6小时的Al-20Pb复合粉用挤压比为4的模具进行包套挤压,得到了高致密度的Al-20Pb合金材料,其孔隙度只有3%左右。该合金中Pb相的尺寸平均只有几个微米,且分布比较均匀。
After being mechanical milled for different time of Al-Pb mixed powders, scanning electron microscopy and electronic probe have been used to analyse the shape and microstructure of mixed powder grains, the micro-hardness and the densification property of the milled powders have also been measured. The results show that, in the course of mechanical milling, the size of Al and Pb mixed powder grains increases at initial stage, then decreases gradually, and trendes to be stable at last. The Al and Pb mixed powders form composite powders with laminar structure, the lamins thin with milling time increasing, the laminar structure cracke in to fine dispersing grains at last. The hardness of Al-Pb composite powders increases and its compact density decreases with milling time increasing. At last, the composite powder of Al-20Pb obtained by milling for 6h is extruded with extruding-ratio of 4, and the Al-20Pb alloy with very low porosity, very fine grain and very homogenous distribution of Pb phase is obtained.
出处
《粉末冶金技术》
EI
CAS
CSCD
北大核心
2005年第5期347-351,共5页
Powder Metallurgy Technology
基金
山东省自然科学基金(Y2002F22)
哈尔滨工业大学交叉学科基金(HIT.MD.2000.36)资助项目
