摘要
55CrSi线材被广泛应用于汽车发动机活塞环的制造中,在生产过程中易存在线材截面硬度不均匀的现象。研究了热处理工艺对线材组织和性能均匀性的影响。采用扫描电镜、金相显微镜、能谱仪、维氏硬度计研究了材料的组织、成分与性能。试验结果显示,热处理中奥氏体化状态对后续的组织和性能有重要影响。当奥氏体化温度较低或时间较短时,金相组织中出现较大尺寸白色块体,该块体为软相,导致硬度低。当奥氏体化程度高时,金相组织中白色块体尺寸较小,组织和性能均匀性提高。奥氏体化过程不充分时,EDS检测发现材料碳分布不均匀,低硬度区碳含量低,为0.2%左右,高硬度区碳含量高,为0.43%左右。奥氏体化程度高,有利于碳元素分布均匀性,以及淬火回火后的性能均匀性。
55CrSi wire rod is widely used in the manufacturing of piston rings of automobile engines.In the process of production,it is easy to have uneven hardness of wire section.The effects of heat treatment process on the uniformity of microstructure and properties of the wire rod were studied.The structure,composition and properties of the material were tested by scanning electron microscope,metallographic microscope,energy spectrometer and Vickers hardness tester.The experimental results show that the austenitizing state during heat treatment has an important influence on the subsequent microstructure and properties.When the austenitizing temperature is low or the time is short,a large white block appears in the metallographic structure,which is a soft phase,resulting in low hardness.When the degree of austenitization is high,the size of white block in metallographic structure is small,and the uniformity of structure and properties is improved.When the austenitizing process is not sufficient,it is found that the carbon distribution of the material is uneven by EDS detection,the carbon content in the low hardness zone is low,about 0.2%,and the carbon content in the high hardness zone is high,about 0.43%.The high degree of austenitization is conducive to the uniformity of carbon element distribution and the uniformity of properties after quenching and tempering.
作者
谢美龙
付雪松
陈国清
XIE Meilong;FU Xuesong;CHEN Guoqing(School of Materials Science and Engineering,Dalian University of Technology,Dalian 116024,China)
出处
《热加工工艺》
北大核心
2025年第9期23-26,32,共5页
Hot Working Technology
基金
国家国际科技合作专项项目(2015DFR60370)
辽宁省自然科学基金项目(2022-YKLH-04)。
作者简介
谢美龙(1998-),男,山东潍坊人,硕士,主要研究方向:钢的热处理工艺与组织性能,E-mail:1660418614@qq.com;通讯作者:陈国清,男,教授,主要研究方向:材料加工过程组织性能控制、高性能构件近净成形、新材料制备及超塑性、塑性加工技术,E-mail:gqchen@dlut.edu.cn。
