摘要
某航空发动机GCr15钢制轴承垫圈在锻件制造阶段发现其冲击韧性指标远低于标准要求。对锻件的锻造、热处理工艺路线进行检查,并对热处理试样进行拉伸、硬度和冲击韧性测试,观察试样断口形貌。结果表明,拉伸断口低倍形貌呈纤维区+解理区+剪切唇,其中纤维区的高倍形貌为浅韧窝+撕裂棱线,而放射区为解离台阶+大量撕裂棱线,为韧-脆混合特性。冲击韧性断口为密布的解理河流花样,属于脆性断裂。试样表层的显微组织为高碳针状马氏体+弥散分布球形碳化物,芯部显微组织为高碳针状马氏体+晶内球形碳化物+晶界网状碳化物。马氏体与碳化物等级符合标准要求。冲击韧性不达标的原因在于航空材料手册提供的冲击功-回火温度曲线有误(回火温度150~200℃对应的冲击功范围为500~800 kJ/m2),需手册编制单位重新审查冲击功数据的科学性。
The impact toughness index of an aero engine GCr15 steel bearing gasket was found to be much lower than the standard requirement during the forging manufacturing stage.The forging and heat treatment process of the forging were checked,and the tensile,hardness and impact toughness of the heat treatment sample were tested,and the fracture morphology of the sample was observed.The results show that the low-power morphology of tensile fracture is fiber region+cleavage region+shear lip.The highpower morphology of fiber region is shallow dimple+tear prism,while the radiating region is dissociation step+large number of tear prism,which is a tough-brittle mixture.The impact ductile fracture is a dense pattern of cleavage river,which belongs to brittle fracture.The surface microstructure of the sample is high carbon acicular martensite+dispersed spherical carbide,and the core microstructure is high carbon acicular martensite+intracrystal spherical carbide+grain boundary network carbide.Martensite and carbide grades meet the requirements of standard.The reason why the impact toughness is not up to standard is that the impact work-tempering temperature curve provided by the aviation materials manual is incorrect(the impact energy range corresponding to the tempering temperature of 150 to 200℃is 500 to 800 kJ/m2),and the manual preparation unit needs to re-examine the scientific nature of the impact energy data.
作者
鲁小芳
李亚非
佟飞
向顺成
高军
LU Xiaofang;LI Yafei;TONG Fei;XIANG Shuncheng;GAO Jun(Zhangjiajie Institute College of Aeronautic Industry,Zhangjiajie 427000,Hunan,China;Changsha University of Science and Technology,Changsha 410100,Hunan,China;Guizhou Aero-Engine Research Institute,Guiyang 550081,Guizhou,China)
出处
《热处理技术与装备》
2025年第2期28-32,共5页
Heat Treatment Technology and Equipment
基金
湖南省教育厅科学研究项目课题(23C1038)。
