Al-high Si alloys were designed by the addition of Cu or Mg alloying elements to improve the mechanical properties. It is found that the addition of 1 wt.% Cu or 1 wt.% Mg as strengthening elements significantly impro...Al-high Si alloys were designed by the addition of Cu or Mg alloying elements to improve the mechanical properties. It is found that the addition of 1 wt.% Cu or 1 wt.% Mg as strengthening elements significantly improves the tensile strength by 27.2% and 24.5%, respectively. This phenomenon is attributed to the formation of uniformly dispersed fine particles(Al2Cu and Mg2Si secondary phases) in the Al matrix during hot press sintering of the rapidly solidified(gas atomization) powder. The thermal conductivity of the Al-50 Si alloys is reduced with the addition of Cu or Mg, by only 7.3% and 6.8%, respectively. Therefore, the strength of the Al-50 Si alloys is enhanced while maintaining their excellent thermo-physical properties by adding 1% Cu(Mg).展开更多
采用高频感应炉熔炼制备Al-50Si合金,通过金相、热物理性能、SEM和能谱分析仪对不同参数下得到的Al-50Si合金缺陷和热物理性能进行测试分析。结果表明,当熔炼频率为930 Hz,用4 g C_2Cl_6精炼剂精炼一次时铸态宏观样貌较好。随着温度的升...采用高频感应炉熔炼制备Al-50Si合金,通过金相、热物理性能、SEM和能谱分析仪对不同参数下得到的Al-50Si合金缺陷和热物理性能进行测试分析。结果表明,当熔炼频率为930 Hz,用4 g C_2Cl_6精炼剂精炼一次时铸态宏观样貌较好。随着温度的升高,气体的溶解度变小,气体更容易从金属液中逸出所以930 Hz熔炼时效果较好;随着精炼次数和精炼剂单次用量的增加,气孔有逐渐变大的趋势。这是因为精炼时金属液剧烈翻腾不但会卷入新的气体,还可能会使金属液中的气孔逐渐聚集所以气孔会逐渐变大。铸造气孔的存在降低了材料的热导率,同时气孔的增加也使得材料的线膨胀系数变大。展开更多
文摘Al-high Si alloys were designed by the addition of Cu or Mg alloying elements to improve the mechanical properties. It is found that the addition of 1 wt.% Cu or 1 wt.% Mg as strengthening elements significantly improves the tensile strength by 27.2% and 24.5%, respectively. This phenomenon is attributed to the formation of uniformly dispersed fine particles(Al2Cu and Mg2Si secondary phases) in the Al matrix during hot press sintering of the rapidly solidified(gas atomization) powder. The thermal conductivity of the Al-50 Si alloys is reduced with the addition of Cu or Mg, by only 7.3% and 6.8%, respectively. Therefore, the strength of the Al-50 Si alloys is enhanced while maintaining their excellent thermo-physical properties by adding 1% Cu(Mg).
文摘采用高频感应炉熔炼制备Al-50Si合金,通过金相、热物理性能、SEM和能谱分析仪对不同参数下得到的Al-50Si合金缺陷和热物理性能进行测试分析。结果表明,当熔炼频率为930 Hz,用4 g C_2Cl_6精炼剂精炼一次时铸态宏观样貌较好。随着温度的升高,气体的溶解度变小,气体更容易从金属液中逸出所以930 Hz熔炼时效果较好;随着精炼次数和精炼剂单次用量的增加,气孔有逐渐变大的趋势。这是因为精炼时金属液剧烈翻腾不但会卷入新的气体,还可能会使金属液中的气孔逐渐聚集所以气孔会逐渐变大。铸造气孔的存在降低了材料的热导率,同时气孔的增加也使得材料的线膨胀系数变大。
