(1. 湖北汽車工業(yè)學(xué)院 材料工程系， 十堰 442002；
2. Department of Mechanical Engineering, University of Waterloo, Waterloo, Ontario N2L 3G1, Canada)
摘 要: 研究了表面處理對微型點焊鍍鎳鋼板和鎳板時電極失效的影響。 結(jié)果表明： 微型點焊鍍鎳鋼板和鎳板時電極的失效主要是電極頭部的塑性變形以及電極和鍍鎳板之間局部焊接的斷裂發(fā)生在電極表面而導(dǎo)致的電極磨損；表面涂敷TiC的CuCrZr電極的壽命(1 200點)是CuCrZr電極壽命(600點)的兩倍， 表面處理能提高電極壽命的主要原因是表面涂敷的TiC顆粒能阻礙電極和鍍鎳板之間的局部焊接， 以及減小電極表面的塑性變形。
關(guān)鍵字: 鍍鎳鋼板; 微型點焊;電極失效機(jī)制; 表面處理
electrode degradation during micro-resistance spot welding
（ 1. Department of Materials Engineering,
Hubei Automobile Industrial Institute, Shiyan 442002, China;
2. Department of Mechanical Engineering,
University of Waterloo, Waterloo, Ontario N2L 3G1, Canada）
Abstract: The effects of TiC coating on electrode tip surface on electrode degradation mechanism were studied during micro-resistance spot welding of nickel-plated steel to nickel sheet. The results indicate that the electrode degradation mechanism is basically caused by deformation at electrode tip and wear due to fracture of local welding between the electrode tip face and sheet happened at electrode surface during micro-resistance spot welding of nickel-plated steel to nickel sheet. The electrode tip life of CuCrZr electrode with TiC coating (1 200 welds) doubles that of CuCrZr electrode (600 welds), because the TiC particles contained in the coating deposits can prevent local welding between the electrode surface and nickel-plated steel, then decrease the deformation of electrode surface.
Key words: nickel-plated steel; micro-resistance spot welding; electrode degradation mechanism; surface treatment
