贝氏体等温时间对两相区轧制舰船用钢组织和性能的影响  

Effect of bainite isothermal time on microstructure and properties of ship steel prepared by intercritical rolling

作　　者：田亚强 姚硕 张明山 李红斌 胡宝佳 陈连生 TIAN Ya-qiang;YAO Shuo;ZHANG Ming-shan;LI Hong-bin;HU Bao-jia;CHEN Lian-sheng(Key Laboratory of the Ministry of Education for Modern Metallurgical Technology,North China University of Science and Technology,Tangshan 063210,China)

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

出　　处：《材料热处理学报》2024年第7期147-153,共7页Transactions of Materials and Heat Treatment

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)和电子万能试验机等研究了两相区轧制后贝氏体等温处理时间对舰船用钢组织性能的影响。结果表明:当在450℃等温处理10 min到1 h时,试验钢的显微组织由马奥岛(M/A岛)、少量粒状贝氏体和铁素体组成;随着等温时间的延长,M/A岛逐渐减少,粒状贝氏体增多;当等温时间达到5 h时,显微组织由粒状贝氏体和少量铁素体组成。随着等温时间的继续延长,粒状贝氏体不断长大,残留奥氏体分解为碳化物,试验钢的屈服强度为1116~1150 MPa,抗拉强度为1121~1156 MPa。随着等温时间的延长,试验钢的断后伸长率和冲击吸收能量均呈先升高后降低趋势,在等温5 h时,伸长率和冲击吸收能量均达到最大值,分别为15.6%和81.2 J。Effect of isothermal treatment time on microstructure and properties of ship steel prepared by intercritical rolling was studied by means of scanning electron microscopy(SEM),X-ray diffraction(XRD) and electronic universal testing machine.The results show that when subjected to isothermal treatment at 450 ℃ for 10 min to 1 h,the microstructure of the experimental steel is composed of martensite/austenite islands(M/A islands),a small amount of granular bainite and ferrite.As the isothermal time increases,the M/A islands gradually decrease and the granular bainite increases.When the isothermal time reaches 5 h,the microstructure consists of granular bainite and a small amount of ferrite.As the isothermal time continues to increase,the granular bainite continues to grow,the retained austenite decomposes into carbides,the yield strength of the experimental steel is 1116-1150 MPa,and the tensile strength is 1121-1156 MPa.With the increase of isothermal time,the elongation and impact absorbed energy of the experimental steel show a trend of first increasing and then decreasing.After 5 h of isothermal treatment,the elongation and impact absorbed energy reach their maximum values,which are 15.6% and 81.2 J,respectively.

关 键 词：两相区轧制 贝氏体等温时间 舰船用钢 粒状贝氏体 冲击吸收能量 

分 类 号：TG156.1[金属学及工艺—热处理]