复合变质对不同镁量原位Mg_2Si/Al复合材料组织的影响

Influence of Complex Modification on Microstructure in In-situ Mg_2Si/Al-Si Composite with Different Mg Contents

在不同镁含量铸造Mg2Si/A1-Si复合材料过程中,加入混合稀土氧化物与CaCO3作为变质剂,并采用光学显微镜研究了复合变质对组织的影响。结果表明,变质剂加入量与镁的加入量有关。0.2%的混合稀土氧化物与0.3%的CaCO3使Al-10%Mg-20%Si的初生Mg2Si尺寸由原来的75μm减小到25μm左右,变质效果显著,并初步探讨了其变质机理。

The effects of mixed rare-earth oxides and CaCO3 on microstructure in in-situ Mg2Si/Al-Si composite with different Mg contents were investigated by optical microscope. The results show that the modificator content depends on Mg content; the size of primary Mg2Si in Al-10% Mg-20%Si decreases from 75 pan to 25μm, after modified by 0.2% mixed rare-earth oxides and 0.3% CaCO3; the effect of modification is obvious. And then the principles of modification is discussed.