电弧炉冶炼超低碳汽车用钢的工艺实践

Process practice of smelting ultra-low carbon automobile steel by the electric arc furnace

介绍了“废钢管理→EAF→RH真空处理→板坯连铸”工艺生产超低碳汽车板DC04钢的情况,针对短流程冶炼过程中C、N及残留元素难以控制的问题,围绕反应原理及生产流程进行了重点分析,并分别采取了从废钢管理、电炉、真空精炼到连铸全过程的针对性工艺改进方案及技术性措施,包括建立废钢数字化管理模式、优化电炉终点控制及废钢预热工艺、RH真空度精确控制及渣系优化、连铸原辅料标准修订及过程参数优化等措施,将钢中碳、氮元素质量分数分别降至25×10^(-6)、30×10^(-6)以下,钼、镍、铜、硼残余元素质量分数分别降至0.02%、0.05%、0.08%、0.0006%以下,满足超低碳汽车板DC04钢的标准要求,提升了产品质量。

The production of ultra-low carbon automobile plate DC04 steel by scrap management-EAF-RH vacuum treatment-slab continuous casting process was introduced.Aiming at the problem that C,N and residual elements were difficult to control in short-process smelting process,the reaction principle and production process were emphatically analyzed.The targeted process improvement schemes and technical measures were adopted from scrap management,EAF,vacuum refining to continuous casting,including establishing digital scrap management mode,optimizing EAF endpoint control and scrap preheating process,accurate control of RH vacuum degree and optimization of slag system,revising raw materials standards for continuous casting and optimizing process parameters.The mass fraction of carbon and nitrogen elements in steel was reduced to below 0.0025%and 0.0030%respectively,and the mass fraction of residual elements of molybdenum,nickel,copper and boron in steel were reduced to below 0.02%,0.05%,0.08%and 0.0006%respectively,which met the standard requirements of DC04 steel for ultra-low carbon automobile plates and improved the product quality.