热轧车轮用钢的系列化开发

SERIAL DEVELOPMENT OF HOT-ROLLED WHEEL STEEL

汽车车轮是汽车的重要部件,影响着汽车的安全性和可靠性,除了应具有良好的强度与韧性匹配以外,还应具有良好的延伸凸缘性、良好的冷成形性、较高的疲劳强度和良好的焊接性能。为了适应商用汽车工业的发展,河钢集团唐钢公司在车轮用钢市场调研的基础上,结合2050生产线先进的装备技术,通过在C-Mn成分体系中添加微合金元素Nb、Ti等元素,并严格控制N、H、O、P、S等元素含量,利用控轧控冷工艺开发出了可以满足钢质车轮用途的强度级别为330~650 MPa的汽车车轮系列用钢。强度420 MPa以下车轮用钢的组织为铁素体+珠光体,晶粒度8.0~10.5,高强度车轮用钢的组织为铁素体+粒状贝氏体组织+少量珠光体,晶粒度11.0~13.5;系列钢的抗拉强度为358~682 MPa,屈服强度为268~611 MPa,A 50为24%~41%,均满足性能要求。实际应用表明,厚规格轮辐用钢报废率在3‰以内,轮辋用钢报废率控制在9‰左右,抗疲劳性能优良。

Automobile wheels are important parts of automobiles,affecting the safety and reliability of automobiles,in addition to good strength and toughness matching,should also have good extension flange,good cold formability,high fatigue strength and good welding performance.In order to adapt to the development of the commercial vehicle industry,HBIS Group Tangsteel Co.,Ltd.on the basis of wheel steel market research,combined with the advanced equipment technology of the 2050 production line,by adding microalloying elements Nb,Ti and other elements to the C-Mn composition system,and strictly controlling the content of N,H,O,P,S and other elements,using the controlled rolling and cooling process to develop a series of automotive wheel series steel that can meet the strength level of 330~650 MPa for steel wheels.The structure of wheel steel with strength below 420 MPa is ferrite+pearlite,grain size 8.0~10.5,the structure of high-strength wheel steel is ferrite+granular bainite structure+a small amount of pearlite,grain size 11.0~13.5;the tensile strength of series steel is 358~682 MPa,yield strength is 268~611 MPa,A 50 is 24%~41%,all of which meet the performance requirements.The practical application shows that the scrap rate of thick gauge spoke steel is within 3‰,and the scrap rate of rim steel is controlled at about 9‰,and the fatigue resistance is excellent.