贝氏体等温温度对两相区轧制舰船用钢组织性能的影响  

Effect of isothermal bainite temperature on microstructure and properties of ship steel after intercritical rolling

作　　者：田亚强 姚硕 张明山 李红斌 胡宝佳 陈连生 Tian Yaqiang;Yao Shuo;Zhang Mingshan;Li Hongbin;Hu Baojia;Chen Liansheng(Key Laboratory of the Ministry of Education for Modern Metallurgical Technology,North China University of Science and Technology,Tangshan Hebei 063210,China)

机构地区：[1]华北理工大学教育部现代冶金技术重点试验室,河北唐山063210

出　　处：《金属热处理》2024年第11期167-171,共5页Heat Treatment of Metals

基　　金：河北省自然科学基金重点项目(E2022209049)。

摘　　要：采用扫描电镜(SEM)、X射线衍射仪(XRD)和力学性能测试等手段,研究了两相区轧制后贝氏体区等温温度对舰船用钢组织性能的影响。结果表明,热轧后,试验钢组织为M/A岛和少量铁素体。等温温度为400、450℃并空冷至室温时,组织为板条贝氏体、粒状贝氏体和铁素体。等温温度为500℃时,组织为粒状贝氏体和铁素体。试验钢经过贝氏体等温处理后,屈服强度在981~1116 MPa之间,抗拉强度在997~1124 MPa之间。在500℃等温时,相比其他两种温度,残留奥氏体体积分数最大,导致伸长率和冲击吸收能量分别达到最大值11.7%和104.1 J。综合比较,在450℃等温处理时,试验钢的性能达到最佳,抗拉强度为1124 MPa,屈服强度为1116 MPa,伸长率为11.3%,冲击吸收能量为71.4 J。Effect of isothermal bainite temperature on microstructure and mechanical properties of ship steel after intercritical rolling was investigated by means of scanning electron microscope(SEM),X-ray diffractometer(XRD)and mechanical properties tests.The results show that the microstructure is M/A island and a small amount of ferrite after hot rolling.When the isothermal temperature is 400℃and 450℃followed by air cooling,the microstructure is composed of the lath bainite,granular bainite and ferrite.When the isothermal temperature is 500℃,the microstructure is composed of granular bainite and ferrite.The yield strength of the tested steel ranges from 981 MPa to 1116 MPa,and the tensile strength ranges from 997 MPa to 1124 MPa after bainite isothermal treatment.Compared to the other two isothermal temperatures,the retained austenite volume fraction is the highest when isothermal treated at 500℃,resulting in the elongation and impact absorbed energy reaching the maximum values of 11.7%and 104.1 J,respectively.Through comprehensive comparison,the mechanical properties of the steel reaches the optimum when isothermal treated at 450℃,with the tensile strength of 1124 MPa,yield strength of 1116 MPa,elongation of 11.3%,and impact absorbed energy of 71.4 J.

关 键 词：舰船用钢 两相区轧制 贝氏体等温处理 组织 力学性能 

分 类 号：TG156.1[金属学及工艺—热处理]