海洋大气环境对铝合金电连接器壳体腐蚀及电气性能影响

目的研究海洋大气环境对2A12和6061铝合金电连接器性能的影响。方法开展2A12和6061铝合金电连接器在海南万宁试验站4 a棚下暴露试验,通过宏微观形貌观察和电气性能测试对比分析两种铝合金电连接器壳体的腐蚀差异和电气性能变化。结果两种铝合金电连接器壳体均出现镀层鼓泡、剥落和基体腐蚀,6061铝合金电连接器壳体腐蚀程度高于2A12铝合金电连接器。2A12铝合金基体发生点蚀和晶间腐蚀,6061铝合金基体发生剥蚀,基体腐蚀产物堆积,导致镀镍层开裂剥落,进而失去防护作用。相对于导通性能、耐压强度,电连接器的绝缘电阻对海洋大气环境更为敏感。结论铝合金化学镀镍壳体电连接器在热带海洋大气环境下不适宜长期使用。

Effects of Marine Atmospheric Environment on Corrosion and Electrical Performance of Aluminum Alloy Electrical Connector Shell

Objective To study the effects of marine atmospheric environment on performance of 2A12 and 6061 aluminum alloy electrical connectors. Methods Atmospheric environment test of 2A12 and 6061 aluminum alloy electrical connectors were carried out in Wanning Test Station for 4 a. Corrosion difference and change of electrical properties of two kinds of aluminum alloy electrical connectors were analyzed by morphology observation and electrical performance test. Results Coating bubbling, spalling and matrix corrosion occurred in the shell of two kinds of aluminum alloy electrical connectors. The corrosion degree of 6061 aluminum alloy electrical connector shell was higher than that of 2A12 aluminum alloy. Pitting corrosion and intergranular corrosion occurred in 2A12 aluminum alloy base, and corrosion occurred in 6061 aluminum alloy base. The accumulation of corrosion products resulted in cracking and spalling of nickel plating layer. Compared with continuity and compression strength, the insulation resistance of electrical connectors was more sensitive to marine atmosphere environment. Conclusion Electrical connectors of electroless nickel-plated aluminum alloy shell are unsuitable for long-term use in tropical marine atmospheric environment.