镀锌钢板点焊电极的强化技术

Strengthening Techniques of Spot-welding Electrode Applied to Zinc Coated Steel

镀锌钢板的电阻点焊可焊性较差,导致其点焊电极过早失效,因此,点焊电极的强化引起了广泛的重视。主要强化方法分为基体强化和表面强化。点焊电极通常是Zr、Cr等强化并经冷作硬化的Cu合金,通过Al2O3、TiB2、ZrO2等对基体进行弥散强化,或对基体深冷处理,或通过渗金属Ti、电刷镀Co、离子注入W、电火花沉积TiC、TiB2、TiN等对电极进行表面强化,可有效地提高电极的使用寿命。其中,电火花沉积TiC、TiB2涂层电极是一种新的电极表面强化技术,经过广泛工业应用效果显著。

The poor weldability of zinc coated steel results in early failure of the resistance spot-welding electrodes. Hence, reinforcement of the electrode draws growing attention, and matrix enhancement and surface modification are two major technologies. The electrode is commonly cold worked copper alloy strengthened by Zr and Cr alloys. It can be further ,hardened by dispersion strengthening of the matrix with Al2O3, TiB2, ZrO2, and cryogenic treatment, surface treatment such as brush plate of Co, ion injection of W, electrospark deposition of TiC, TiB2 and TiN. All these methods are available to improve its lifetime. TiC based coating deposited on its surface by electrospark is a hopeful surface technology among them, which, proves to be very effective by industrial applications.