摘要
借助光谱仪、蔡司光学显微镜和洛氏硬度计等分析手段对38CrMoAlA钢主轴失效件的化学成分、非金属夹杂物、断口裂纹形貌、显微组织和硬度进行检测与观察,分析并讨论了造成该工件裂纹产生的影响因素。结果表明:38CrMoAlA钢主轴的化学成分、硬度、渗氮层、非金属夹杂物、带状组织均符合标准要求;显微组织晶粒粗大,为贝氏体+珠光体,非预期使用态组织(回火索氏体),故工件硬度高、内应力较大、脆性较大,在应力的作用下易产生裂纹,导致脆性断裂失效。
Chemical composition,non-metallic inclusions,fracture crack morphology,microstructure and hardness of a failed 38CrMoAlA steel shaft were tested and observed by using spectrometer,Zeiss metallographic microscope and Rockwell hardness tester,and influencing factors of the workpiece crack were discussed.The results show that the chemical composition,hardness,nitriding layer,non-metallic inclusions,and band structure of the 38CrMoAlA steel shaft meet the standard requirements.But the microstructure of the shaft is bainite+pearlite,which is unexpected structure(tempered sorbite),and meantime,the grain is coarse.Therefore,the workpiece has high core hardness,large internal stress and brittleness,and it is easy to produce cracks under the action of stress,leading to brittle fracture failure.
作者
徐祺昊
杨礼林
夏明
秦晨
耿振岳
姜亚君
赵莉萍
Xu Qihao;Yang Lilin;Xia Ming;Qin Chen;Geng Zhenyue;Jiang Yajun;Zhao Liping(School of Materials and Metallurgy,Inner Mongolia University of Science and Technology,Baotou Inner Mongolia 014010,China)
出处
《金属热处理》
CAS
CSCD
北大核心
2021年第9期268-272,共5页
Heat Treatment of Metals
