ZG0Cr13Ni5Mo不锈钢不同比例保护气体焊接工艺研究

Investigation on welding process of ZG0Cr13Ni5Mo martensitic stainless steel at different proportions protective atmosphere

针对纯Ar气体保护焊焊接不锈钢时,焊接过程中的阴极斑点飘移现象,以及不锈钢的润湿性、流动性较差等原因,在焊缝中极易形成咬边、两侧熔合不良等焊接缺陷。采用加入一定量的氧化性气体对焊接接头的化学成分、缺陷率和力学性能进行研究分析。结果表明,采用Ar+2%O_2和Ar+10%CO_2保护气体焊接后,可以克服阴极斑点飘移,提高电弧稳定性,同时改善熔池形状,增加熔化金属流动性,从而减少了气孔、未熔合等缺陷,并且随着氧化气体的比例增加造成焊缝中的夹渣增加,并带来接头塑性和韧性的下降。

In MIG welding process of martensitic stainless steel at pure Ar protective atmosphere,there is the drift phenomenon of cathode spot,and the poor wettability and fluidity result in welding defects such as undercut and incomplete fusion in both sides of weld.So a litde oxidizing gas was added into the Ar protective atmosphere,and then the defect rates,chemical composition,and mechanical properties of the welded joint were analyzed.The results show that the above problem can be solved by add 2%O_2 or 10%CO_2 to Ar gas.But with the increase of the ratio of the oxidizing gas,there are the increase of slag on the weld,and the decrease of the toughness of the joint.