回火工艺对20Cr1Mo1VTiB螺栓钢组织和性能的影响  

Influence of tempering technique on microstructureand properties of 20Cr1Mo1VTiB bolt steel

作　　者：杨滨 史一男 赵吉庆[2] 杨钢[2] YANG Bin;SHI Yinan;ZHAO Jiqing;YANG Gang(Collaborative Innovation Center of Steel Technology,University of Science and Technology Beijing,Beijing 100083,China;Institute for Special Steels,Central Iron and Steel Research Institute,Beijing 100081,China)

机构地区：[1]北京科技大学钢铁共性技术协同创新中心,北京100083 [2]钢铁研究总院特殊钢研究所,北京100081

出　　处：《南昌工程学院学报》2024年第4期15-20,27,共7页Journal of Nanchang Institute of Technology

基　　金：国家863计划重大项目(2012AA03A507);国家863计划重点项目(2008AA031702)。

摘　　要：利用SEM、TEM、EBSD等研究了回火工艺对20Cr1Mo1VTiB螺栓钢组织和力学性能的影响。回火后,该钢贝氏体板条合并长大,板条界变得模糊。随着回火温度升高和回火时间延长,板条合并长大明显。相比于700℃×4 h回火,720℃×4 h回火和700℃×6 h回火后贝氏体板条尺寸分别增加了44.98 nm和55.93 nm。随着回火温度升高和回火时间延长,20Cr1Mo1VTiB螺栓钢中的主要碳化物为VC、TiC、M_(3)C尺寸变大,形貌从方形向球形转变;同时,该钢的抗拉强度和硬度降低,延伸率和-20℃冲击韧性有所提高。The mechanical properties of 20Cr1Mo1VTiB bolt steel were tested and characterized by SEM,TEM and EBSD.The microstructures and tensile properties of 20Cr1Mo1VTiB bolt steel tempered at different temperatures and holding times were studied.The results show that the bainite laths in the 20Cr1Mo1VTiB bolt steel merged and grew up after tempering,and the boundary of the laths became fuzzy.With the increase of tempering temperature and tempering time,the extent of the lath merging increased.Compared with 700℃×4h tempering,the bainite lath sizes in the steel tempered at 720℃for 4h and at 700℃for 6h increased by 44.98 nm and 55.93 nm respectively.The main carbides in the steel were VC,TiC and M_(3)C.Their sizes grew with the increase of tempering temperature and tempering time,and the morphologies changed from square to spherical.At the same time,the tensile strength and hardness as well as the elongation and impact toughness at-20℃of the tested steel decreased and increased respectively.

关 键 词：20Cr1Mo1VTiB螺栓钢 回火工艺 贝氏体 拉伸性能 

分 类 号：TG161[金属学及工艺—热处理]