感应淬火条件下Cu-Ni低碳低合金钢的强化机制  

Strengthening mechanism of Cu-Ni-bearing low-carbon low-alloyed steel under induction quenching treatment

作　　者：孙铭璇 孟利[1] 张宁[1] 张波[1] 梁丰瑞[2] 罗小兵[2] Sun Mingxuan;Meng Li;Zhang Ning;Zhang Bo;Liang Fengrui;Luo Xiaobing(Metallurgical Technology Institute,Central Iron and Steel Research Institute,Beijing 100081,China;Research Institute of Engineering Steels,Central Iron and Steel Research Institute,Beijing 100081,China)

机构地区：[1]钢铁研究总院有限公司冶金工艺研究所,北京100081 [2]钢铁研究总院有限公司工程用钢研究院,北京100081

出　　处：《金属热处理》2023年第4期204-210,共7页Heat Treatment of Metals

基　　金：国家重点研发计划(2017YFB0903901)。

摘　　要：采用电子背散射衍射(EBSD)、扫描电镜(SEM)、X射线衍射仪(XRD)和TEM原位拉伸试验等分析了含Cu-Ni低碳低合金钢经感应加热淬火+时效的显微组织及Cu粒子与强度的关系,并对强化机制进行了量化分析。结果表明,试验钢经980℃感应淬火+670℃时效的综合性能优于1030℃感应淬火+680℃时效;含Cu-Ni低碳低合金钢呈现多种强化机制,包括沉淀强化、晶界强化、位错强化、固溶强化和点阵阻力,其中沉淀强化与晶界强化为主要强化机制,二者占比超过70%;理论计算出Cu粒子在Orowan机制中最小临界尺寸为28.50 nm,在TEM原位拉伸中观测到位错在Cu粒子周围发生塞积,并按照绕过机制与尺寸为44.57 nm的Cu粒子发生交互作用。Microstructure and the relationship between Cu particles and strength of the Cu-Ni-bearing low-carbon low-alloyed steel under induction-heat quenching and aging was analyzed by means of electron back-scatter diffraction(EBSD),scanning electron microscope(SEM),X-ray diffractometer(XRD)and in-situ tension in transmission electron microscope(TEM),and the quantitative analysis of strengthening mechanism was discussed.The results show that the comprehensive properties of the tested steel after induction quenching at 980℃and aging at 670℃is better than that induction quenching at 1030℃and aging at 680℃.There are many strengthening mechanisms for the Cu-Ni-bearing low-carbon low-alloyed steel,including precipitation strengthening,grain size strengthening,forest dislocations strengthening,solid solution strengthening and lattice friction stress,among which precipitation strengthening and grain size strengthening are the main strengthening method,accounting for more than 70%.In theoretical calculation,the minimum critical size of Cu particles is 28.50 nm in Orowan mechanism,and the dislocation pile-up around the Cu particles,and they interact with a Cu particle with size of 44.57 nm according to the bypass mechanism during in-situ tension in TEM.

关 键 词：含Cu-Ni钢 感应淬火 Cu粒子 强化机制 

分 类 号：TG142.33[一般工业技术—材料科学与工程]