超级双相不锈钢生产工艺实践

Process practice of super duplex stainless steel

超级双相不锈钢S32760生产工艺流程为20tEAF→AOD→LF→30cm模铸。由于S32760成分设计中高铬、低磷、低硫、超低碳这一特点,冶炼后期钢水过氧化程度严重。为改善钢水洁净度、降低钢中氧质量分数,通过采取合理的脱氧造渣工艺,采用Al-Si-Ca复合脱氧,使钢中气体、夹杂物得到了有效控制,改善了钢水洁净度,成品钢中硫质量分数控制在0.002%以下,氧质量分数控制在0.004%以下。

The production process of super duplex stainless steel S32760 is 20t EAF→AOD→LF→30cm mold casting.As the feature of the S32760 composition design is high Cr,low P,low S and ultra-low carbon,the peroxidative degree of steel is serious in the later period of smelting.In order to improve the purity of molten steel and reduce the oxygen mass fraction in steel,the Al-Si-Ca composite deoxidation was adopted,which effectively controlled the gas and inclusions in steel and improved the purity of molten steel.The sulfur and oxygen mass fraction in the finished steel were stably controlled less than 0.002% and 0.004%,respectively.