Al-Mg-Si合金线导电率演变规律与机制

通过不同温度退火处理模拟架空输电用Al-Mg-Si合金线的热服役环境,对不同退火温度下Al-Mg-Si合金线的导电率演变规律与机制进行了研究。结果表明,Al-Mg-Si合金线的导电率随着退火温度的升高呈现3阶段特征,第一阶段温度为90~150 ℃,Al-Mg-Si合金线导电率略微增大,缺陷的回复是本阶段Al-Mg-Si合金线导电率增大的原因;第二阶段温度为150~200 ℃,析出相的长大和固溶原子的析出导致Al-Mg-Si合金线导电率大幅增大;第三阶段温度为200~300 ℃,晶粒长大是Al-Mg-Si合金线导电率缓慢增大的主要原因。

Evolution law and mechanisms of electrical conductivity of Al-Mg-Si alloy wire

Thermal service environment of Al-Mg-Si alloy wire used for overhead transmission lines was simulated by annealing at different temperatures,the evolution law and mechanisms of electrical conductivity of the Al-Mg-Si alloy wire annealed at different temperatures were investigated.The results show that the electrical conductivity increasing of the annealed Al-Mg-Si alloy wire could be divided into three stages with the increase of annealing temperature.In the first stage(temperature ranges from 90℃to 150℃),the electrical conductivity increases slightly,which is caused by the defect recovery.In the second stage(temperature ranges from 150℃to 200℃),the growth of precipitates and the precipitation of solid solution atoms lead to the rapid increase of the electrical conductivity.In the third stage(temperature ranges from 200℃to 300℃),the grain growth is the main reason for the slow increase of the electrical conductivity.