Abstract: The C75S spring steel (/% ：0.72 ~0.74C , 0.29 ~0.32Si , 0.73~0.77Mn , 0.006~0.010P , 0.002~0.005S) hot-rolled wire coil is successfully developed by process flow 100 t EAF→LF→RH→220 ~ 300 mm² cast square bloom→150 mm x 150 mm rolled billet→ϕ5.5~25 mm wire coil, in wire coil the proportion of inclusions below 10μm is about 92% ,the content of sorbite reaches 95% ,and the average lameller distance between die two phases of ferrite and cementite is about 0.1~0.2μm. Also,the wire R_m is 1022 MPa and A is 17.5%.

摘要： 通过工艺流程：100 t电弧炉→LF→RH-→220~300 mm²连铸方坯→450 mm x 150 mm轧坯→ϕ5.5 ~ 25 mm 线材盘条,成功开发生产C75S 弹簧钢(/%：0.72~0.74C，0.29~0.32Si，0.73~0. 77Mn，0.006～0.010P，0.002～0.005S)热轧盘条，盘条10μm以下的夹杂比例约92%，索氏体含量达到95% ,铁素体和渗碳体两相交替的片层平均间距为0.1~0.2μm,盘条Rm为1022 MPa，A为17.5%。