不同淬回火工艺对40Cr钢微观组织与力学性能的影响  

Effect of Different Quenching and Tempering Processeson Microstructure and Mechanical Properties of 40Cr Steel

作　　者：谭邦俊 廖玉松[1] 胡斌 TAN Bangjun;LIAO Yusong;HU Bin(School of Mechanical and Automotive Engineering,Chuzhou Polytechnic,Chuzhou 239000)

机构地区：[1]滁州职业技术学院机械与汽车工程学院,安徽滁州239000

出　　处：《常州工学院学报》2022年第6期32-36,共5页Journal of Changzhou Institute of Technology

基　　金：滁州职业技术学院科研重点项目(DS2019002)。

摘　　要：用金相显微镜、SEM电镜、拉伸试验及冲击试验等研究不同热处理工艺对40Cr钢微观组织与力学性能的影响。在微观组织上,不同热处理工艺的主要微观金相组织为回火索氏体且晶粒度等级为9级,而经亚温淬回火后还出现了铁素体。在力学性能上:860°C淬火+600°C回火工艺有利于提高40Cr钢的硬度、屈服强度及抗拉强度性能;860°C淬火+600°C回火+770°C亚温淬火+600°C回火可提高40Cr钢伸长率、断面收缩率和冲击韧性性能;对退火40Cr钢进行770°C亚温淬火+600°C回火后,钢的塑性和冲击韧性比淬回火+亚温淬回火差,硬度、屈服强度及抗拉强度比淬回火性能差。研究结果表明:淬回火可提高40Cr钢硬度和强度性能,淬回火+亚温淬回火可提升40Cr钢冲击韧性和塑性性能。The effect of different heat treatment processes on the microstructure and mechanical properties of 40Cr steel is studied by means of metallographic microscope,SEM,tensile test and impact test.In terms of microstructure,the main metallographic microstructure of different heat treatment processes is tempered sorbite with the grain size grade of 9,and ferrite also appears after intercritical quenching and tempering.In terms of mechanical properties,860°C quenching+600°C tempering process is conducive to improving the hardness,yield strength and tensile strength of 40Cr steel,860°C quenching+600°C tempering+770°C intercritical quenching+600°C tempering improves the elongation,section shrinkage and impact toughness of 40Cr steel.After 770°C intercritical quenching+600°C tempering of the annealed 40Cr steel,the plasticity and impact toughness of the steel are worse than those after quenching and tempering+intercritical quenching and tempering,and the hardness,yield strength and tensile strength are worse than those after quenching and tempering.The results show that quenching and tempering can improve the hardness and strength of 40Cr steel,and quenching and tempering+intercritical quenching and tempering can improve the impact toughness and plasticity of 40Cr steel.

关 键 词：40Cr 冲击韧性 屈服强度 抗拉强度 微观组织 

分 类 号：TG142.1[一般工业技术—材料科学与工程]