变质对过共晶铝-硅合金金相组织、电阻率及机械性能的影响

The Effect of Modification on the Microstructure, Resistivity and Mechanical Properties of Hypereutectic Alminium—Silicon Alloy

试验研究了Al—23％Si、Al—25％Si、Al—28％Si合金的P变质,RE变质,P与RE联合变质和P—Cu与Na联合变质。对变质效果进行了综合比较。得出了电阻率受初晶哇变质效果及共晶硅变质效果双重影响。抗拉强度主要受初晶硅粒度及形状的影响,延伸率主要受共晶组织形态影响的结论。

The modification of Al—23％Si, Al—25Si and Al—28％Si alloys with P or RE, and P combined with RE and P—Cu alloy combined with Na are investigated. The results of modification are evaluated synthetically. It is concluded that the resistivity is affected by the twofold result of modification of primary silicon and eutectic silicon. The tensil strength is affected mainly by the size and shape of primary silicon and the percentage elongation is affected mainly by the morphology of eutectie structure.