Jiang Xiangdong, Chen Tijun, Ma Ying, et al. Effects of SiC on the Grain Refinement in AZ91D Magnesium Alloy[J]. Special Casting & Nonferrous Alloys, 2009,29(8):763-766.
Jiang Xiangdong, Chen Tijun, Ma Ying, et al. Effects of SiC on the Grain Refinement in AZ91D Magnesium Alloy[J]. Special Casting & Nonferrous Alloys, 2009,29(8):763-766.DOI:
SiC对AZ91D镁合金晶粒细化效果的影响
摘要
研究了SiC对AZ91D镁合金组织的影响。通过在不同温度添加不同含量的Mg-SiC混合粉末
在760~780℃、SiC含量为0.20%时
AZ91D镁合金晶粒达到75μm。利用光学显微镜和扫描电子显微镜及其电子探针观察发现
Mg-SiC混合粉末的加入使得AZ91D镁合金的晶粒尺寸显著减小
这是因为Mg-SiC混合粉末加入后反应生成了少量的Al4C3
Al4C3颗粒可以作为α-Mg的结晶核心
同时SiC颗粒本身也可以作为α-Mg的异质结晶核心。对于AZ91D合金而言
Mg-SiC混合粉末是一种良好的晶粒细化剂。
Abstract
Effects of SiC content on microstructure of AZ91D magnesium alloy were observed with adding varied Mg-SiC powder at different temperature by OM (optical microscope) and SEM (scanning electron microscope)as well as EPMA. The grain with size of 75 μm in the AZ91D magnesium alloy can be presented with 0.20% SiC addition at 760
7
80 ℃. The results reveal that the grain size in the AZ91D magnesium alloy is remarkably reduced with Mg-SiC mixed powder
which is attributed to the creation of a little Al4C3 phase as the nuclei of α-Mg phase due to the reaction of Mg-SiC mixed powder and SiC as heterogeneous nuclei of α-Mg phase. Mg-SiC mixed powder is a desirable grain refiner for the AZ91D magnesium alloy.