高强塑积汽车用中锰钢的热变形与组织性能  

Hot deformation and microstructure properties on automotive medium manganese steel with high strength-ductility balance

作　　者：苏张磊[1] 李玮 罗志敏 Su Zhanglei;Li Wei;Luo Zhimin(College of Mechanical and Electrical Engineering,Henan Vocational College of Agricultural,Zhengzhou 451450,China;School of Materials Science and Engineering,Zhengzhou University,Zhengzhou 450001,China)

机构地区：[1]河南农业职业学院机电工程学院,河南郑州451450 [2]郑州大学材料科学与工程学院,河南郑州450001

出　　处：《锻压技术》2022年第8期241-248,共8页Forging & Stamping Technology

基　　金：郑州市科技攻关项目(173SGYG2612232);国家自然科学基金资助项目(21908217)。

摘　　要：采用扫描电镜、透射电镜和拉伸试验机等手段,研究了热压缩变形量(0%、25%、50%和75%)对奥氏体逆相变退火态汽车用中锰钢的显微组织和力学性能的影响。结果表明:随着热压缩变形量从0%增加至75%,退火态中锰钢中马氏体板条的平均宽度从0.96μm减小至0.34μm、碳化物的平均粒径从Φ38 nm减小至Φ20 nm,且碳化物的体积分数也随着热压缩变形量的增加而增大。经过热压缩变形处理的退火态中锰钢中的奥氏体含量、断后伸长率和强塑积均高于未经过热压缩变形的试样,且当热压缩变形量为50%和75%时,退火态中锰钢的强塑积均高于33.4 GPa·%,符合第3代汽车钢对强塑积≥30 GPa·%的要求,这主要与热压缩变形后退火态中锰钢中板条马氏体较为细小、碳化物尺寸小且体积分数较大等有关。The influences of hot compression deformation amounts(0%,25%,50%and 75%)on the microstructure and mechanical properties of austenitic reverse transformation annealed automotive medium manganese steel were studied by means of scanning electron microscope,transmission electron microscope and tensile testing machine.The results show that with the increasing of hot compression deformation amount from 0%to 75%,the average width of martensitic lath in annealed medium manganese steel decreases from 0.96μm to 0.34μm,the average particle diameter of carbide decreases fromΦ38 nm toΦ20 nm,and the volume fraction of carbide increases with the increasing of hot compression deformation amounts.The austenite content,elongation and strength-ductility balance of annealed medium manganese steel after hot compression deformation treatment are higher than those of samples without hot compression deformation.When the hot compression deformation amount is 50%and 75%,the strength-ductility balance of annealed medium manganese steel is higher than 33.4 GPa·%,which meets the requirements of the third generation automotive steel for the strength-ductility balance≥30 GPa·%.It is mainly related to the fine lath martensite and small size and large volume fraction of carbide in annealed medium manganese steel after hot compression deformation.

关 键 词：中锰钢 热压缩变形 奥氏体逆相变退火 显微组织 力学性能 

分 类 号：TG142.1[一般工业技术—材料科学与工程]