目的 通过对阴极等离子电解放电机制进行讨论，提出大面积沉积复杂形状试样的解决办法。方法 在电解液中添加表面活性剂和氯铂酸制备 Pt 颗粒弥散的复合涂层，通过测试电流密度-电压曲线，分析气膜放电机制，通过扫描电子显微镜对涂层的表面、截面形貌进行分析表征。 结果 在电解液中添加表面活性剂或者在阴极区施加微珠，使气膜层更均匀，同时降低了沉积涂层的电流密度。随着 Pt 含量的增加，涂层孔隙率逐渐降低。涂层中弥散的 Pt 颗粒起到了弥散增韧的作用，提高了涂层的断裂韧性和抗剥落性能。 结论 实现了在大面积复杂形状试样上制备陶瓷涂层，并通过在涂层中弥散 Pt 颗粒提高了涂层的致密性。

Objective To propose the methods to prepare coatings on large-area and complex-shape cathode by discussing the breakdown processes. Methods The coatings were prepared by adding surfactant and H2PtCl6?6H2O in solution. The current density-voltage curves were measured and used for analysis of the discharge mechanism of gaseous film. The surface and cross-section morphologies of the coating were studied by SEM. Results Adding surfactant into solution or adding beads in cathode region could result in more even gaseous film and meanwhile decreased the current density. With increasing Pt content, the porosity of coating was gradually decreased. The fracture toughness and spallation resistance of ceramic coating were improved because of the toughening effect of Pt particles. Conclusion The ceramic coatings could be prepared on large-area and complex shape samples by cathode plasma electrolysis deposition, and the compactness of ceramic coating was improved by dispersing Pt particles.