在紫铜上电火花沉积Ni/金属陶瓷涂层的工艺研究

摘要

为了探索电阻点焊电极端面Ni/金属陶瓷涂层的最佳沉积工艺,采用电火花沉积技术在紫铜上沉积Ni/金属陶瓷涂层,研究了工艺参数对沉积速率的影响.实验结果表明:随着沉积电压和电流的增大,沉积速率增大,电压对沉积速率的影响更为明显；但过大的沉积电压和电流将导致涂层表面粗糙度增大,同时出现飞溅和表面氧化；随着沉积电容的增大,沉积速率亦随之增大；保护气体流量和电极转速对沉积速率无明显影响；随着沉积电流和电压的增大,金属陶瓷层的沉积速率增大.但在相同条件下,金属陶瓷层的沉积速率比镍涂层沉积速率低；在合理的沉积工艺条件下,在紫铜上沉积Ni/金属陶瓷涂层界面可以获得良好的冶金结合,涂层硬度由涂层表面向内部逐渐降低.%In order to study the best deposition process of the Ni/metal-ceramic coating on the resistance spot welding electrode, Ni and metal-ceramic coating are deposited onto the copper by electric-spark deposition technology. It is shown that when the deposition voltage and current increase, the deposition rate increases, and the voltage has a more significant impact on the deposition rate. Also, excessive deposition voltage and current will make coating surface much rougher. At the same time, spattering and surface oxidation occur. When the deposition of the capacitor increases, the deposition rate also increases, and the flow of protection gas and electrode rotational speed has no significant effect on the deposition rate. Moreover, when the deposition of the current and voltage increase, the metal-ceramic layer of the deposition rate increases. However, under the same conditions, metal-ceramic coating deposition rate is lower than that of nickel coating. In reasonable deposition conditions, depositing Ni and metal ceramic coating interfaces on the copper can be in a good metallurgical bonding, and the coating hardness decreases from surface to inside.