镀金表面微孔腐蚀的电接触特点资料.pdfVIP

2004年9月 电工 技术学报 V01．19 No．9 第19卷第9期TRANSACTIONS OF CHINA ELECTRoTECHNICAL SOCIETY Sep． 2004 镀金表面微孔腐蚀的电接触特点 李雪清 (北京邮电大学自动化 章继高 学院北京 100876) 摘要 镀金接触材料表面容易出现微孔。由于湿度、腐蚀性气体及尘土颗粒的影响，镀层表 面在微孔处形成腐蚀，降低了连接器的可靠性。通过对长期室内自然暴露的薄镀金样片表面的形 貌、腐蚀状况以及成分分析，同时对腐蚀表面不同位置处的直流接触电阻、高频接触阻抗进行测 试，从而全面分析表面微孔腐蚀对电接触性能的影响。 关键词：镀金 电接触 微孔 微孔腐蚀 中图分类号：TM503．5 The Electric Contact Properties of Pore Corrosion on Gold Plated Surface Li Xueqing Zhang Jigao (Beijing University of Posts and Telecommunications Beijing 100876 China) Abstract Plating defects known aS pores are unavoidable in most noble metal plating thicknesses used in separable electrical contact applications．With the effects of humidity，corrosive gas and dust particles in the air，pore corrosion contaminant appears on the pore site on plating surface and the connector reliability iS lowered．To examine the effects of corroded pores to the electric contact behavior，the surface morphology，chemical composition and physical appearance of the corroded pores are examined．The pore sites on which corrosion products are observed as the core products surrounding by some corrosion rings were examined under optical microscope and SEM．Dust particles are also deposited on gold plating during indoor air exposure．The contact resistance is found changing from outside point to inside point through the stain area，and the values are much higher than normal in the whole stain area．And the contact impedance changed with the sample surface corrosion situation of contact spots and signal frequency．The contact resistance became high and unstable due to the corrosion and when the corrosive products stacked seriously，the contact capacitance should be the domain affect parameter． Keywords：Gold plating，electric contact，porosity，pore corrosion 1 引言 电器触点的质量是影响各种电系统可靠性的 关键因素，针对我国数字传输网的电路质量调查， 发现长期应用于暴露大气中的连接器的接触故障 是造成电路误码多、稳定性差的重要原因之一。系 收稿日期2003—11—12改稿日期2004-05—13 统中失效连接器的接触表面，有大量腐蚀生成物及 尘土的存在。为进一步研究接触表面的腐蚀状况如 何影响接触性能，将触点材料镀金样品暴露在大气 中，发现有严重污染物出现，且集中在微孔位置， 其成分与出现故障的连接器表面污染物有类似