采用风冷预处理的高强钢板变强度热成形工艺  

Hot forming technology of high strength steel sheet with tailored properties by partial cooling pretreatment

作　　者：鲁玉梅 闫少波 王凯军 李贤君 张文良 刘俊杰 杨涛 Lu Yumei;Yan Shaobo;Wang Kaijun;Li Xianjun;Zhang Wenliang;Liu Junjie;Yang Tao(Taiyuan Heavy Industry Heavy Forging Sub Co.,Taiyuan Shanxi 030024,China;Beijing Research Institute of Mechanical and Electrical Technology,Beijing 100083,China)

机构地区：[1]太原重工铸锻件分公司,山西太原030024 [2]北京机电研究所有限公司,北京100083

出　　处：《金属热处理》2021年第10期193-198,共6页Heat Treatment of Metals

摘　　要：高强钢变强度热成形工艺可使同一零件不同区域具有不同的强度与塑性韧性,在保证碰撞完整性的基础上,提高零件区域延展性以实现碰撞吸能,防止碰撞侵入的目的。提出了一种基于定制区域风冷预处理的变强度热成形工艺。搭建了介质为干燥压缩空气的定制区域冷却平台,研究了射流压力0.3~0.7 MPa下,板料分区冷却的温度分布及变化规律;验证了新工艺实现高强钢的变强度热成形的可行性。研究结果表明,分区冷却过程中,随着射流压力的提高,钢板冷却速度逐渐加快,但横向测流及板料内部热传导使得过渡区宽度增加,而负压回风结构的设计则有效降低了横向测流的影响,在损失一定冷却能力的基础上降低过渡区宽度。当射流压力为0.3 MPa,添加回风结构时,当风冷区域温度降低至410℃(Ms点以上),硬区温度缓冷至750℃(Ar_(3)以上),经800℃回火及淬火后,软区得到低强度高塑性的铁素体及片状珠光体组织,硬区得到高强度低塑性的板条马氏体组织。采用新型的变强度热成形工艺及相应的定制区域冷却平台能够实现高强钢板变强度分布。Compared with traditional hot forming technology,the technology with tailored properties can make different regions of the same part have different strength and plastic toughness,so as to improve the ductility of some regions of the part absorbing the collision kinetic energy,and prevent collision intrusion.A new hot forming process of high strength steel with tailored properties by partial cooling pretreatment was proposed as well designing a customized zone cooling platform with dry compressed air as the medium.The temperature distribution and variation of the plate under partial cooling with the jet pressure of 0.3-0.7 MPa and the influence of return air structure on the cooling capacity and transition zone width of the platform were studied.The results show that when the jet pressure is 0.3 MPa and the air return structure is added,when the air cooling zone temperature is reduced to 410℃(Ms),the hard zone temperature is slowly cooled to 750℃(above Ar_(3)).After tempering at 800℃and quenching,the soft zone comprises low-strength and high-plasticity ferrite and lamellar pearlite microstructure,and the hard zone comprises high-strength and low-plasticity lath martensite microstructure.These show that the high strength steel plate with tailored properties can be obtained with the new hot forming process and the customized zone cooling platform.

关 键 词：高强钢 热成形 变强度 分区冷却 过渡区 

分 类 号：TG162.83[金属学及工艺—热处理]