摘要
AA8176型铝合金导线,常被应用在主配电盘与变压器之间。当导线一旦受到火灾破坏,产生短路故障时,出现的短路熔痕金相组织特征与铜、铝导线有所不同。因此,对AA8176型铝合金导线火灾中短路熔痕金相组织特征进行研究,采用辐射热盘加热、酒精燃烧、木材燃烧和汽油燃烧,来模拟真实火场热环境进行试验,利用金相法观察分析金相组织晶粒和内部孔洞特征。试验结果表明,AA8176型铝合金导线火灾中短路熔痕金相组织内部空洞多且密,熔痕端与本体的金相组织界限不明显,晶粒以柱状晶和胞状晶为主。在不同热环境下出现差别,辐射热盘和酒精加热条件下的熔痕内部孔洞形状规整,多呈圆形,晶粒多呈细长的柱状晶和胞状晶;木材和汽油燃烧则出现大量不规则形状的内部孔洞,晶粒更粗大;汽油燃烧条件下的熔痕金相组织存在特殊的长刺痕和刀口痕。为实际工作中区分火灾前短路熔痕,提供方法和借鉴。
AA8176 aluminum alloy wire is often used between the main switchboard and the transformer.When the wire is damaged by fire and a short circuit fault occurs,the characteristics of the short-circuit melted mark appear different from those of the copper and aluminum wires.Therefore,this experiment studies the short-circuit melted mark characteristics of AA8176 aluminum alloy wire fire.Radiant heat plate heating,alcohol burning,wood burning and gasoline burning were conducted to simulate four different thermal environments in real fire field.The metallographic structure and grain characteristics were observed by metallographic method.The test results show that the internal holes are numerous and dense.The metallographic structure boundary of melted end and the main body is not obvious,and the grains are mainly columnar crystals and cell crystals.In different thermal environments,the internal pores of the radiant heat source and the alcohol heat source are regular,mostly round,with elongated columnar crystals and cell crystals;the internal pores of wood and oil burning are irregularly shaped with larger grain size;the molten metallographic structure under oil burning conditions has special long nicks and knife marks.These results provide a method and reference for distinguishing short-circuit melted marks before fire.
作者
林帅
郝云耕
LIN Shuai;HAO Yungeng(Ji’nan Fire and Rescue Division,Shandong Province 250101,China)
出处
《武警学院学报》
2021年第8期5-9,共5页
Journal of the Armed Police Academy
关键词
铝合金导线
火灾中短路
熔痕
金相组织
aluminum alloy wire
short-circuit in fire
melted mark
metallographic structure
