铝硅系铸造铝合金的晶粒细化处理

Grain-refined treatment of Al-Si series casting alloys

研究了往Al-Si合金液中加入钛、硼的铸造铝合金的晶粒细化效果。结果表明,合金显微组织中Si相由粗针状或片状变为细纤维状,α-Al晶粒数量明显增多,且显著细化;合金力学性能获得显著提高,抗拉强度σb平均提高30-40 MPa,伸长率平均提高3%-5%。

By use of adding Ti and B elements into liquid Al-Si aluminum alloy,its grain-refined effect and the major cause are investigated.The results show that coarse needle-shape Si phase in the alloy microstructure changes into fine fibre-like shape and the amount of α-Al phase increases obviously,the grain size fines markedly.This results in enhancement of mechanical properties,such as the tensile strength increased by 30-40 MPa and the elongation increased by 3%-5%.