铝合金导线过电流熔痕微观形貌特征

Microstructure characteristics of overcurrent melt trace of aluminum alloy wire

为判断线路发生过电流时电弧故障点位置,模拟不同过电流条件下AA8030型铝合金导线的过电流故障,通过场发射电子扫描显微镜分析导线过电流不同区域熔痕微观形貌特征。结果表明:电弧熔断点处熔痕标志性微观形貌特征为蜂窝状和雪花状痕迹;非电弧作用区域熔痕标志性微观形貌特征为针叶状痕迹;电弧熔断点外侧熔渣区标志性微观形貌特征为球状痕迹。该结论可为调查人员判断过电流电弧故障点提供参考。

In order to determine the location of the arc fault point when the line overcurrent occurs,the overcurrent faults of AA8030 aluminum alloy wire under different overcurrent conditions are simulated,and the microstructure characteristics of the melt marks in different areas of overcurrent of the wire are analyzed by field emission scanning electron microscope.The results show that the micromorphological characteristics of the melting marks at the arc fusion point are honeycomb and snowflake.The signature micro morphology of the fusion mark in the non-arc area is the needle-shaped trace.The characteristic microscopic appearance of the slag area outside the arc melting point is spherical trace.This conclusion can provide reference for investigators to judge the fault point of overcurrent arc.