时效对铝镁硅合金线材力学性能和导电率的影响

Effect of aging condition on mechanical properties and electrical conductivity of Al-Mg-Si alloy wire

通过拉伸试验、电阻测试试验、疲劳试验和透射电子显微镜观察,对比研究了不同时效状态下铝镁硅合金线材强度、导电率和疲劳性能的演化规律及机制。结果表明:与欠时效态和过时效态相比,峰时效态的铝镁硅合金线材具有最高的抗拉强度、最大的伸长率和最优的疲劳性能。均匀弥散分布的球状析出相导致的析出强化和位错绕过析出相的方式是峰时效态铝镁硅合金线材兼具强度、塑性和疲劳性能优异的根本原因。随着时效时间的延长,铝镁硅合金线材导电率不断增大的主要原因是固溶原子的析出和析出相的长大。

The mechanisms behind the evolutions of the strength,electrical conductivity and fatigue properties of the Al-Mg-Si alloy wires under different aging conditions were investigated by the tensile test,resistance test,fatigue test and transmission electron microscope observations.The results show that the peak-aged Al-Mg-Si alloy wires have the highest tensile strength,elongation and fatigue properties compared with the under-aged and over-aged Al-Mg-Si alloy wires.The precipitation strengthening and the improvement of slip uniformity caused by uniformly dispersed spherical precipitates are the key reasons for the peak-aged Al-Mg-Si alloy wires with high-strength,high-elongation and excellent fatigue properties.Besides,the electrical conductivity of the Al-Mg-Si alloy wire increases with the aging time,which is mainly due to the precipitation of solid solution atoms and the growth of precipitated phases.