回火温度对35CrMo钢组织和性能的影响  

Effect of Tempering Temperature on Microstructure and Properties of 35CrMo Steel

作　　者：王戈 张巨伟 武淑艳[1] 马野[1] 张达 唐彪 WANG Ge;ZHANG Juwei;WU Shuyan;MA Ye;ZHANG Da;TANG Biao(School of Materials Science and Engineering,Jiamusi University,Jiamusi,Heilongjiang 154000,China)

机构地区：[1]佳木斯大学材料科学与工程学院,黑龙江佳木斯154000

出　　处：《信息记录材料》2025年第4期1-3,7,共4页Information Recording Materials

基　　金：黑龙江省教育厅基本科研业务费基础研究项目(2023-KYYWF-0564)。

摘　　要：为了提高35CrMo钢的塑韧性,同时兼顾其强度性能,本研究采用淬火及回火的热处理工艺,探究回火温度对35CrMo钢组织和性能的影响。采用金相显微镜、扫描电子显微镜、显微硬度计、冲击试验机及电液伺服万能试验机等手段深入探究不同回火温度对35CrMo钢的显微组织变化及力学性能的影响。研究结果表明:35CrMo钢在淬火后的主要组织结构为板条状马氏体,并伴有微量残余奥氏体;在500~650℃范围内进行2 h回火处理时,随着回火温度的升高,碳化物开始在针状铁素体的边缘及其内部析出,碳化物数量增多且分布更均匀,铁素体发生回复再结晶并逐渐等轴化,位错密度逐渐降低,固溶强化、位错强化效果减弱,导致35CrMo钢的硬度和强度降低,塑韧性提高。同时,随着回火温度的升高,35CrMo钢硬度从723.2 HV降至509.9 HV,抗拉强度从1207.9 MPa降至879.4 MPa,断裂强度从767.0 MPa降至584.0 MPa;断后伸长率、断面收缩率呈现出先小幅降低后上升的变化规律;抗冲击载荷性能增强,冲击功从114.3 J升至188.6 J,冲击韧性从142.9 J/cm^(2)升至235.7 J/cm^(2)。综合考虑强塑积指标,本研究的最佳热处理工艺参数为:860℃奥氏体化1 h,500℃回火2 h。To enhance the plasticity and toughness of 35CrMo steel while maintaining its strength,this study investigated the effects of tempering temperature on its microstructure and mechanical properties through quenching and tempering heat treatments.Techniques such as metallographic microscopy,scanning electron microscopy,microhardness testing,impact testing,and electro⁃hydraulic servo universal testing were employed to analyze structural changes and mechanical behavior.The results indicate that the quenched 35CrMo steel primarily consists of lath martensite with trace retained austenite.When tempered at 500-650℃for 2 h,carbides precipitated at the edges and within acicular ferrite as the tempering temperature increased.The carbides became more numerous and uniformly distributed,while the ferrite underwent recovery and recrystallization,gradually becoming equiaxed.Dislocation density decreased,weakening solid solution strengthening and dislocation strengthening effects.Consequently,the hardness and strength of 35CrMo steel decreased,while plasticity and toughness improved.Specifically,hardness decreased from 723.2 HV to 509.9 HV,tensile strength from 1,207.9 MPa to 879.4 MPa,and fracture strength from 767.0 MPa to 584.0 MPa.Elongation and reduction of area initially decreased slightly before rising.Impact resistance increased significantly,with impact energy rising from 114.3 J to 188.6 J and impact toughness from 142.9 J/cm^(2) to 235.7 J/cm^(2).Considering the strength-ductility trade⁃off,the optimal heat treatment parameters were determined as:austenitizing at 860℃for 1 h followed by tempering at 500℃for 2 h.

关 键 词：35CRMO钢 回火温度 显微组织 力学性能 

分 类 号：TG115.5[金属学及工艺—物理冶金]