40Sn-（60-x）Bi-xMg合金的组织、硬度和熔点研究

Microstructure, Hardness and Melting Point of 40Sn-（60-x）Bi-xMg Alloys

通过机械合金法制备了40Sn-（60-x）Bi-x Mg（x=0.2-1.4,为重量百分含量）合金。使用SEM、XRD、DSC和显微硬度计分析了合金的组织结构、熔点和显微硬度。结果表明,40Sn-（60-x）Bi-x Mg合金由α和β相组成;含镁合金的硬度比不含的高。当镁的浓度低于1%时,硬度随镁的浓度增加逐渐增加;当镁浓度再增加,硬度又下降;当镁浓度为1%时,硬度达到最大值,为52.3 HV。添加少量的镁,合金熔点下降。镁浓度为0.2%时,熔点达到最低值,为136.66℃。当添加镁量超过1%,合金的熔点比40Sn-60Bi合金的高。

40Sn-（60-x）Bi-x Mg（x=0.2-1.4, weight percentage）alloy powders were fabricated by mechanical alloying method. The microstructure, melting point temperature and microhardness of the alloys were analyzed by SEM, XRD, DSC and microhardness tester. The results shows that 40Sn-（60-x）Bi-x Mg alloys are composed of α and β phases. The alloys with magnesium have higher hardness. The hardness increases with magnesium addition when the magnesium concentration is less than 1%. After that, the hardness decreases. The maximum is 52.3 HV at the concentration of 1%. A little magnesium addition lowers the melting point temperature of the alloys. The melting point reaches the minimum about 136.66℃ at 0.2% of magnesium. When magnesium concentration is more than 1%, the melting point is higher than that of 40Sn-60 Bi.