高能微弧合金化沉积氮化物陶瓷覆盖层及其耐蚀性能分析

isadvantages of the present candidate metallic materials for bipolar plate are low corrosion resistance and high contact resistance in acidic environment for an extended period of time that can cause power degradation or cell failure. Therefore, great attempts are conducted to improve the corrosion resistance of metals while keeping low contact resistance. In the present study a high- energy micro- arc alloying process is adopted to prepare a TiCN coating on 304 stainless steel bipolar plates with a metallurgical bonding between the coating and substrate. The corrosion characteristics of TiCN coatings are seriously affected by deposition parameters such as output voltage, power, frequency, and flow rate of gas. The results showed that with the increasing power, the diameter of the deposited circles of TiCN increased while the corrosion current density of the coating decreased; with the increasing frequency and the decreasing pulse energy for a single deposited spot, the corrosion current density of the coating increased. The effect of deposition parameters on corrosion behavior of TiCN coatings is also discussed in detail.