采用超音速等离子喷涂技术在45#钢基体上制备 Ni60/高铝青铜梯度涂层,并进行高频感应重熔处理。通过 SEM、XRD 等手段分析了感应重熔前后涂层的组织结构特征、相结构变化以及界面元素扩散情况。结果表明,超音速等离子喷涂层在基体/Ni60结合面处以机械咬合为主,在 Ni60/高铝青铜涂层界面处有轻微熔结特性,形成了机械结合和轻微冶金结合的混合结合方式。感应重熔后,Ni60中间层分别与基体、高铝青铜涂层进行充分的双向扩散熔合。在Ni60和基体间形成结构致密、无孔隙的冶金扩散带,元素扩散迁移后不同元素呈现梯度或均匀分布形式。在 Ni60和高铝青铜涂层之间分层界面基本消失,形成了完全的一体化涂层,涂层中元素扩散呈现梯度形式。
The gradient coating of Ni60/high aluminum copper alloy was prefabricated on 45 # steel substrate by supersonic plasma spraying and induction remelting.The characteristics of organizational structure,the trans-formation of phase structure,element diffusion were analyzed by means of SEM and XRD.The results indicated that the mechanical adhesion was the main way between the matrix and Ni60 coating by the supersonic plasma spraying,the slight sinter properties appear at the interface between Ni60/high aluminum bronze coating,the interface was the mechanical combination and mild metallurgical combination of hybrid combination way.The fully bidirectional diffusion fusion of Ni60 was appeared between the matrix and high aluminum copper alloy coating after the induction remelting.A metallurgical bonding was formed between the Ni60 and the matrix, whose structure was dense and seamless,and whose elements form gradient or uniform distribution.The in-tegrate coating was formed which has not distinct metallurgical belt.The boundary between the Ni60 and the high aluminum copper coating disappeared.The diffused element in this coating distribute as the gradient form.