汽车底盘用500 MPa级热轧酸洗钢板的开发

Development of 500 MPa Grade Hot-rolled Pickled Steel Plate for Automobile Chassis

通过热轧厂热轧和冷轧厂盐酸酸洗,试制了含钛和不含钛的两种热轧酸洗钢板。采用金相显微镜、透射电子显微镜和拉伸试验机研究了两种试制钢板的显微组织和性能。结果表明:两种钢板的显微组织均由铁素体和珠光体组成,其屈服强度达到400 MPa以上,抗拉强度高于500 MPa,断后伸长率大于30%。与不含钛的钢相比,含钛钢的晶粒细小,屈服强度和抗拉强度高,断后伸长率低,屈强比高。

Two kinds of hot-rolled pickled steel plates with and without titanium were trialproduced by hot-rolling in a hot rolling plant followed by pickling with hydrochloric acid in a cold rolling plant.The microstructure and properties of two trial-produced steel plates were studied by means of optical microscope,transmission electron microscope and tensile testing machine.The results showed that the microstructure of two steel plates was composed of ferrite and pearlite,and the yield strength was above 400 MPa,the tensile strength was above 500 MPa,and the elongation was over 30%.Compared with the steel without titanium,the titanium-containing steel exhibited finer grain,and thus higher yield strength,tensile strength and yield ratio,but lower elongation.