摘要
研究了稀土元素的加入对Al Mg2Si合金组织及性能的影响。结果表明:在常规铸造条件下,Al Mg2Si合金中初晶Mg2Si为粗大的多角形块状。经过稀土元素变质后,合金中初晶Mg2Si得到明显细化,并成为分布较均匀的块状或球团状,RE对Mg2Si相从液态合金中的形核和长大过程有重要的影响。当稀土元素(混合稀土RE、Ce)加入量为0 8%时,初晶Mg2Si最细小。RE的加入,降低了初晶Mg2Si相的形核温度或生成更多细小的形核质点,从而促进了形核。稀土元素的加入使Al 20%Mg2Si合金的拉伸性能得到了很大提高,抗拉强度由225MPa提高到260MPa,伸长率由2 56%提高到4 4%。
The influence of RE on microstructure and mechanical property of AI-Mg2Si alloy has been studied. The results showed that the primary Mg2Si phase of AI-Mg2Si alloy was solidified into large polygonal shape in traditional condition. After RE was added in the AI-Mg2Si alloy, the polyhedral primary Mg2Si became rod / granular-like and its distribution became more even. RE had important influence on the nucleation and growth of Mg2Si. When RE added is 0.8% of alloy weight, the finer primary Mg2Si is obtained. The reason is that RE reduced the nucleation temperature of primary Mg2Si crystals or formed many particles favorable nucleate. RE improved the tensile strength of Al-20%Mg2Si from 225 MPa to 260 MPa and the elongation from 2.56% to 4.4%.
出处
《铸造》
EI
CAS
CSCD
北大核心
2005年第3期238-240,245,共4页
Foundry
