摘要
为了研究15CrMo无缝钢管缩口变形前后显微组织和力学性能变化,对15CrMo无缝钢管进行冷挤压缩口成型,对钢管缩口变形前后做显微组织观察、硬度和拉伸性能测试以及断口形貌分析。结果表明,缩口区域内部晶粒发生变形,晶体组织产生片层之间的相对滑移,位错密度增加,导致抗拉强度和硬度得到显著提高,而塑性下降,产生加工硬化现象;对缩口区域进行退火后原畸变晶粒变为等轴晶粒,位错密度降低,塑性和强度有所改善。通过对比缩口退火态与原始锻态钢管的数据,结果显示两者的显微组织和力学性能接近。
In order to study the changes of microstructure and mechanical properties of 15CrMo seamless steel tube before and after shrinkage deformation,15CrMo seamless steel tube was formed by cold extrusion.The microstructure,hardness,tensile properties and fracture morphology were observed before and after the steel tube deformation.The results show that the grain deformation occurs in the reduced diameter area,the relative slip between lamellae occurs in the crystal structure,and the dislocation density increases,which leads to the significant increase in tensile strength and hardness,while the plasticity decreases,resulting in work hardening phenomenon.After annealing,the original deformed grains become equiaxed grains,the dislocation density reduces,and the plasticity and strength are improved.By comparing the data of annealed steel tube with that of forged steel tube,the results show that the microstructure and mechanical properties are close to each other.
作者
华龙龙
刘涛
洪磊
洪亮
HUA Longlong;LIU Tao;HONG Lei;HONG Liang(School of Materials Engineering,Jiangsu University of Technology,Changzhou 213000,China;Jiangsu Beite Pipe Fitting Co.,Ltd.,Taizhou 225500,China)
出处
《热加工工艺》
北大核心
2025年第4期137-141,共5页
Hot Working Technology
基金
国家自然科学青年基金项目(51601078)
江苏省政府留学奖学金项目(JS-2019-322)。
关键词
15CrMo
缩口变形
显微组织
力学性能
15CrMo
deformation of contraction
microstructure
mechanical properties
