火灾前铜导线短路熔痕浸蚀方法研究

Study on Etching Methods of Primary Short Circuited Melted Beads of Copper Wire

火灾事故调查中,火灾前短路熔痕是认定短路故障引发火灾的关键证据。但熔痕中有些组织难以通过化学浸蚀的方法清晰地呈现出来。针对铜导线短路熔痕,在现行标准基础上,尝试使用新的浸蚀剂,研究浸蚀剂配比方法和浸蚀时间,最终确定最优的浸蚀方法。结果表明,三氯化铁盐酸溶液和三氯化铁盐酸酒精溶液有较好的浸蚀效果,硝酸铁溶液不完全适用于浸蚀火灾前短路熔痕,硝酸溶液可以作为一种新的火灾前短路熔痕的浸蚀剂。

In any fire investigations, the primary short circuited melted beads are the key evidence to identify short circuit fault as the cause of fires. But microstructure of some melted beads is very difficuh to present by chemical etching. On the basis of industry standards available, this paper applies new chemical reagents to etch the beads. The best method is selected according to the proportion of different etchants and the time of etching in experiments. Experimental results show that ferric chloride hydrochloric acid solution and alcohol solution have a better etching effect, that ferric nitrate solution cannot be used to etch short circuited melted beads; that saltpeter solution is a new chemical reagent to etch primary short circuited melted beads.