BHW35钢热丝TIG堆焊接头组织及性能研究

Microstructure and properties of surfacing welded joint by hot tire tungsten inert-gas welding process

采用热丝TIG堆焊的方法,在钢基体上堆焊不锈钢耐蚀层,分析了堆焊层接头的显微组织和性能。分析结果表明,基体和堆焊层结合良好,堆焊层组织呈典型的树枝状晶,多层堆焊形成了树枝状晶与柱状晶交替出现的组织;多层堆焊中,硬度沿堆焊层深度呈波浪变化,过渡层中的硬度值较高,而堆焊层交界处的硬度值有所下降;电化学性能表明,在5%HCl溶液中,接头各区抗电化学腐蚀能力由大到小的顺序依次为:过渡层、顶层堆焊层、熔合区、基体;堆焊耐蚀层具有良好的耐晶间腐蚀性能。

By using hot wire tungsten inert-gas welding method,the corrosion resistant layer of stainless steel was deposited on the surface of BHW35 steel,and the microstructure and performance of the deposited metal were analyzed.The results show that the base metal and the deposited metal layer bonds well.The typical structure of the surfacing layer metal is dendritic structure.Alternative structure of dendritic grain and columnar grain were formed in multilayer welding process.The hardness has changed along depth of surfacing layer,and it is higher in the transition layer and decreases at the interface between two layers.It is proved that,corrosion resistance in 5%HCl solution from large to small are transition layer,top surfacing layer,the fused zone,and the base metal.The deposited metal has better inter-crystalline corrosion resistance.