摘要
为研究火灾中过电流故障条件下铜导线的痕迹特征,模拟火灾条件,制备了过电流多股铜导线样品,利用扫描电镜(SEM)对线芯表面的微观组织进行了观察,并与未通电的原始导线进行了对比。结果表明,随着过电流程度的加重,线芯表面依次呈现出剥离脱落、块状开裂、珊瑚状小颗粒等典型痕迹;在明火燃烧和热辐射作用下,过电流线芯表面分别出现大块熔结和波浪状熔流痕迹。试验结果可为火灾物证鉴定和火灾调查提供参考。
In order to study the trace characteristic of copper conductors under overcurrent faults, simulating the fire condition, the multi stranded copper wires were prepared. The microstructure of the wire surface was observed by scanning electron microscopy(SEM), which was compared with the original wire sample without electricity. The results show that with the increase of the degree of overcurrent, the core surface generates peeling off, massive cracking, tiny coral-like particle and other typical traces in turn. Under the action of open flame combustion and thermal radiation, the surface of the overcurrent core generates large melting and wavy flow traces, respectively. The experimental results can provide references for fire material evidence identification and fire investigation.
引文
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