温轧温度对中碳钢组织与力学性能的影响  

Effect of warm rolling temperature on microstructure and mechanical properties of medium carbon steel

作　　者：田亚强 赵志浩 杨子旋 徐海卫 韩赟 郑小平 李红斌 陈连生 Tian Yaqiang;Zhao Zhihao;Yang Zixuan;Xu Haiwei;Han Yun;Zheng Xiaoping;Li Hongbin;Chen Liansheng(Key Laboratory of the Ministry of Education for Modern Metallurgy Technology,North China University of Science and Technology,Tangshan Hebei 063210,China;Key Laboratory of Impact and Safety Engineering,Ministry of Education of China,Ningbo University,Ningbo Zhejiang 315211,China;Technology Center,Shougang Jingtang United Iron&Steel Co.,Ltd.,Tangshan Hebei 063200,China)

机构地区：[1]华北理工大学教育部现代冶金技术重点实验室,河北唐山063210 [2]宁波大学冲击与安全工程教育部重点实验室,浙江宁波315211 [3]首钢京唐钢铁联合有限责任公司技术中心,河北唐山063200

出　　处：《金属热处理》2022年第6期19-25,共7页Heat Treatment of Metals

基　　金：国家自然科学基金(51801106);河北省科技厅重点研发项目(20311004D);河北省自然科学基金高端钢铁冶金联合基金(E2020209124,E2020209127,E2020209040);河北省高等学校科学技术研究项目(ZD2019064,QN2019051)。

摘　　要：采用透射电镜(TEM)、扫描电镜(SEM)、室温拉伸等手段,研究了650~730℃温轧温度对0.46%C中碳钢的组织演变及力学性能的影响。结果表明,经90%的轧制变形,试验钢铁素体晶内引入大量位错,渗碳体片层产生应力集中导致层片状渗碳体弯曲、扭折、碎化为颗粒状。随着温轧温度的降低,位错增殖明显,渗碳体球化率增加,分布越来越均匀,抗拉强度和伸长率整体上升。当温轧温度为650℃时,渗碳体球化最好,抗拉强度877 MPa,断后伸长率16.0%,综合力学性能最好。拉伸断口结果表明,随着温轧温度的降低,试验钢的断裂机制由韧-脆混合断裂转变为韧性断裂,塑性提高。Effect of 650-730 ℃ warm rolling temperature on microstructure evolution and mechanical properties of a 0.46%C medium carbon steel was studied by means of TEM, SEM, room temperature tensile test. The results show that after 90% rolling deformation, a large amount of intragranular dislocations are introduced in the ferrite of the tested steel, the cementite lamella produces stress concentration, which causes the lamellar cementite to bend, kink, and shear into granules. With the decrease of warm rolling temperature, the dislocation multiplication is obvious, the spheroidization rate of cementite increases and the distribution becomes more and more uniform, the strength and the elongation increase overall. At the warm rolling temperature of 650 ℃, the cementite is greatly spheroidized, the tensile strength is 877 MPa, and the elongation after fracture is 16.0%, the tested steel has the best comprehensive mechanical properties. The tensile fracture results show that with the decrease of warm rolling temperature, the fracture mechanism of the tested steel changes from ductile and brittle mixed fracture to ductile fracture, and the ductility increases.

关 键 词：中碳钢 温轧温度 位错密度 显微组织 力学性能 

分 类 号：TG142[一般工业技术—材料科学与工程]