碳化物对非调质钢零件淬硬层组织及性能的影响  

Effect of Carbide on Microstructure and Mechanical Property of Induction Hardening Layer for Parts of Unquenched Steel

作　　者：张英建[1] 鹿云 陈思联[1] 惠卫军[1] 董瀚[1] 

机构地区：[1]钢铁研究总院结构材料研究所,北京100081 [2]第一汽车集团技术中心,吉林长春130011

出　　处：《钢铁》2011年第11期66-70,85,共6页Iron and Steel

基　　金：国家科技支撑计划资助项目(2007BAE51B03)

摘　　要：在扭转疲劳试验中,非调质钢FAS2340半轴零件性能比调质钢42CrMoH零件高出50%以上。为研究其原因,对上述两种半轴零件进行了研究。金相观察发现,在感应淬火过程中FAS2340钢中形成大量规则排列的微小质点,经TEM和相分析对比发现,质点主要由未熔解的渗碳体颗粒构成,并且占总数70%以上Fe3C质点尺寸分布在5～9nm范围内。大量的Fe3C质点促进零件表层晶粒细化,并在随后的淬火冷却过程中形成均匀细小的马氏体组织,零件使用性能得到显著提高。Mechanical properties of Semi-axle of non-quenching and tempering steel（FAS2340） was improved and was 50% higher than quenched and tempered steel（42CrMoH） in torsion fatigue test.In order to clear the reason,two Semi-axles of FAS2340 and 42CrMoH were investigated.Microstructure shows that a large number of reticular small particles are formed in FAS2340 during induction hardening.According to results of TEM and Phase analysis,the small particle is constituted mainly by no-melting cementite particles,and the Fe3C particles（diameter： 5-9 nm） are more than 70%.The austenite grain size of hardened layer is refined accordingly.Then,fine and uniform martensite laths are formed in following quenching process.Performance of parts significantly is increased due to refining microstructure.

关 键 词：非调质 碳化物 Fe3C 渗碳体 组织细化 马氏体 

分 类 号：TG142.1[一般工业技术—材料科学与工程]