300M钢等温淬火相变特性及力学性能  

Isothermal quenching phase transformation characteristics and mechanical properties of 300M steel

作　　者：赵晓宇 张铮 杨慧君[1] 石晓辉[1] 张敏[1,2] 乔珺威[1] Zhao Xiaoyu;Zhang Zheng;Yang Huijun;Shi Xiaohui;Zhang Min;Qiao Junwei(College of Materials Science and Engineering,Taiyuan University of Technology,Taiyuan Shanxi 030024,China;Shanxi Aerospace Equipment Heat Treatment and Surface Treatment Technology Innovation Centre,Taiyuan University of Technology,Taiyuan Shanxi 030024,China)

机构地区：[1]太原理工大学材料科学与工程学院,山西太原030024 [2]太原理工大学山西航天装备热处理与表面处理技术创新中心,山西太原030024

出　　处：《金属热处理》2025年第1期173-179,共7页Heat Treatment of Metals

摘　　要：利用热膨胀仪、彩色金相、扫描电镜和透射电镜等研究了300M钢在Ms附近240~320℃范围内的等温淬火工艺对相变特性和力学性能的影响。结果表明,在Ms以下等温淬火时300M钢先产生无热马氏体,缩短贝氏体相变孕育期。与Ms以上的320℃等温淬火工艺相比,在Ms以下的260℃等温淬火时残留奥氏体由块状M/A岛的形态转变为存在于贝氏体板条之间的薄膜形态,且贝氏体板条平均宽度下降,抗拉强度由1550 MPa提高至1930 MPa,断裂总延伸率由7.7%提高至9.2%,强度和塑性同步提高。Effect of isothermal quenching process at 240-320 ℃ near Ms on the phase transformation characteristics and mechanical properties of 300M steel was studied by means of thermal dilatometer,color metallography,scanning electron microscopy and transmission electron microscopy.The results show that the isothermal quenching below Ms result in athermal martensite produces first and the incubation period of bainite transformation shortened of the 300M steel.Compared with the isothermal quenching process at 320 ℃ above Ms,the isothermal quenching process at 260 ℃ below Ms makes the retained austenite transform from blocky M/A islands to film between bainite laths,the average width of bainite lath decreases,the tensile strength increases from 1550 MPa to 1930 MPa and the total elongation increases from 7.7% to 9.2%,showing that the strength and plasticity increase simultaneously.

关 键 词：300M钢 等温淬火 彩色金相 力学性能 

分 类 号：TG161[金属学及工艺—热处理]