56mm×75mm矩形52CrMoV4弹簧扁钢轧制工艺及孔型设计  

Rolling process and pass design for 56mm×75mm rectangular 52CrMoV4spring flat steel

作　　者：罗景贤 袁林 李佳军 刘智 LUO Jingxian;YUAN Lin;LI Jiajun;LIU Zhi(Hunan Valin Xiangtan Iron and Steel Co.,Ltd.,Xiangtan,441200,China)

机构地区：[1]湖南华菱湘潭钢铁有限公司,湖南湘潭441200

出　　处：《轧钢》2025年第1期156-160,共5页Steel Rolling

摘　　要：规格为56mm×75mm的矩形弹簧扁钢生产难度较大、质量要求高,在轧制过程中极易发生脱方、扭转堆钢等事故,其尺寸、外形和质量难以控制。为此,在湖南华菱湘潭钢铁有限公司原有圆钢生产设备的基础上,对56mm×75mm矩形52CrMoV4弹簧钢进行开发,优化其加热、轧制、缓冷工艺,设计K_(6)、K_(4)、K_(2)专用孔型,实现了不易扭转、尺寸稳定且质量合格的56mm×75mm矩形扁钢的稳定生产,其中K_(6)、K_(4)、K_(2)孔型侧壁斜度和R角逐步减小,提高了轧辊利用率,降低了成本;通过控制加热工艺和缓冷工艺,得到脱碳层厚度0.21~0.24mm、硬度分布320HB~349HB、力学性能均满足客户要求的产品;56mm×75mm矩形52CrMoV4弹簧扁钢1/4宽度和1/2宽度处组织均主要为贝氏体+珠光体+少量铁素体+少量的马氏体。The production of rectangular spring flat steel with dimensions of 56mm×75mm is quite challenging and demands high quality standards.During the rolling process,it is prone to problems such as out-of-square deformation,torsion and steel stacking,making it difficult to control its dimensions,shape and quality.Therefore,the 56 mm×75 mm rectangular 52CrMoV4spring flat steel was developed based on existing round steel production equipment of Hunan Valin Xiangtan Iron and Steel Co.,Ltd.By optimizing the heating,rolling and slow cooling processes,and designing specialized pass designs,namely K_(6),K_(4)and K_(2),the stable production of 56mm×75mm rectangular flat steel with resistance to torsion,stable dimensions and satisfactory quality had been achieved.The side wall inclinations and R-angles of the K_(6),K_(4)and K_(2)pass designs were progressively reduced,enhancing roll utilization and reducing costs.Controlling the heating and slow cooling processes,the product obtained had a decarburized layer thickness of 0.21-0.24mm and a hardness distribution between 320HB and 349HB,with all mechanical properties meeting customer requirements.The microstructure at the 1/4width and the 1/2width of the 56mm×75mm rectangular 52CrMoV4spring flat steel was predominantly bainite+pearlite+a small amount of ferrite+a trace of martensite.

关 键 词：52CrMoV4弹簧钢 56mm×75mm矩形扁钢 孔型设计 工艺优化 脱碳层 力学性能 降低成本 

分 类 号：TG335[金属学及工艺—金属压力加工]