轿车悬架簧用弹簧钢线材的生产实践

影响轿车悬架簧用弹簧钢线材质量的因素主要有线材化学成分、夹杂物数量和形态分布、气体含量、表面质量、脱碳层、显微组织、力学性能及尺寸精度等,通过采用LF精炼炉和RH炉精炼技术,大方坯轻压下技术和控轧控冷技术,控制冶炼、连铸、加热、轧制等工序的关键参数,转炉冶炼时铁水比不低于90%,吹炼终点w(C)≤0.075%,w(P)≤0.010%,w(S)≤0.010%,开轧温度不高于1000℃,预精轧和精轧入口温度低于900℃,减定径入口温度750～800℃,控制60Si2MnA冷速为3～6℃/s,55SiCrA冷速为2～4℃/s,线材质量检验及成品悬架簧测试表明,生产的60Si2MnA和55SiCrA线材质量稳定,能满足轿车悬架簧质量要求。

Production practice of wire rod for automobile suspension spring

The factors, which influence the quality of wire rod for automobile suspension spring, primarily include chemical composition, the quantity, morphology and distribution of inclusions, gas content, surface quality, deearburization layer, microstructure, mechanical property, dimension tolerance etc. Through adopting the refining technology of LF ＋ RH, the soft reduction technology for bloom, the controlled-rolling and contrulled-cooling technology to control the key parameters of process such as smelting, continuous casting, heating and rolling and so on, no less than 90% of hot metal to BOF, no higher than 0.075% of carbon content and 0. 010% of phosphorus and sulfur content before tapping, initial rolling temperature no higher than 1 000℃, pre-finishing and finishing inlet rolling temperature no higher than 900℃, size reducing inlet temperature at 750 -800℃, to control cooling rate 3 -6 ℃/s for 60Si2MnA and 2 -4℃/s for 55SiCrA, through wire rod quality examination and after suspension spring testing, the quality of 60Si2MnA and 55SiCrA wire rod produced by Xingtai Iron Steel is steady, which satisfy the quality requirement of suspension spring for automobile.