奥氏体不锈钢焊丝电渣重熔制备过程脱硫规律

Rearch on the rule of desulfurization in electroslag remelting preparation of nuclear stainless steel wire

文中采用ER309L核级不锈钢焊丝在生产条件下进行了电渣重熔试验,研究了不同渣系对该钢种电渣过程脱硫率的影响。结果表明,采用不同渣系重熔脱硫率不同;电渣重熔过程不同阶段脱硫率呈阶梯式变化规律,在重熔初期脱硫率高于重熔中期,电渣封顶期间脱硫率显著降低,正常重熔阶段脱硫率比较稳定。在CaF2-Al2O3-SiO2渣系中,随SiO2含量的增加脱硫率下降,当SiO2含量达25%时还会导致明显的烧锰增硅现象。采用预熔渣+萤石渣系,萤石配比为20%和30%时,随萤石配比增加,重熔锭底部脱硫率下降,重熔锭顶部脱硫率基本相当;同时随萤石配比增加硅的烧损降低。

Electroslag remelting experiment of ER309L nuclear stainless steel welding wire was carried out in this paper,the influence of different slag systems on desulfurization rate of electroslag process was studied.The results show that the desulfurization rate is different with different electroslag remelting systems.The desulfurization rate in different stages of electroslag remelting showed a step change rule.The desulfurization rate in early remelting is higher than that in middle remelting.The desulfurization rate decreased significantly during electroslag capping,and the desulfurization rate is stable in normal remelting stage.In CaF2-Al2O3-SO2 slag series,the desulfurization rate decreases with the increase of SiO2 content.The content of manganese decreases and the content of silicon increases obviously,when the content of SiO2 reaches 25%.With the increase of CaF2,the desulfurization rate at the bottom of remelted ingot decreased,and the desulfurization rate at the top of remelted ingot is basically the same,when the ratio of CaF2 in the prefused slag+CaF2 slag system is 20%and 30%.At the same time,the burning rate of silicon decreases with the increase of CaF2 ratio.