NM300热轧耐磨钢的低周疲劳性能  

Low cycle fatigue property of hot rolled wear-resistant steel NM300

作　　者：安会龙 颜沛霖 刘需 宋仁伯[2] 黄岩 陈昊天 AN Huilong;YAN Peilin;LIU Xu;SONG Renbo;HUANG Yan;CHEN Haotian(HBIS Materials Technology Research Institute,Shijiazhuang 050023,Hebei,China;School of Materials Science and Engineering,University of Science and Technology Beijing,Beijing 100081,China)

机构地区：[1]河钢材料技术研究院,河北石家庄050023 [2]北京科技大学材料科学与工程学院,北京100081

出　　处：《钢铁研究学报》2024年第1期129-140,共12页Journal of Iron and Steel Research

摘　　要：为了探索商用车先进耐磨部件的服役情况,了解其关键耐磨部件在行驶过程中因颠簸、天气、路况等原因抵抗疲劳失效的能力,以厚度为3.5 mm的热轧TRIP耐磨钢板NM300为研究对象,进行了低周疲劳实验。研究其在不同的应变幅值下的疲劳性能,得到了循环应力响应特征曲线、应力-应变迟滞回线。研究了NM300的Masing效应,循环应力与非弹性应变的关系,循环应变与疲劳寿命的关系等,并对不同应变幅值控制下的NM300低周疲劳断裂机制进行了分析。实验结果表明:NM300在较低的应变幅值控制下表现为循环硬化,在较高的应变幅值控制下表现为循环软化,且随着应变幅值增加,NM300的循环响应应力逐渐增加。当应变幅值小于0.37%时,循环寿命可达104次以上;当应变幅值小于0.19%时,循环寿命可达105次以上。NM300的疲劳断口具有典型的疲劳断裂特征,分为3个区域:疲劳源区、裂纹扩展区和瞬断区,且随应变幅增加,裂纹扩展区面积不断减小,表面逐渐粗糙。疲劳断口的断裂形式以沿晶脆性断裂和沿晶韧性断裂为主,根据热轧耐磨钢的服役条件要求可认为其疲劳性能优良。In order to explore the service status of advanced wear-resistant parts of commercial vehicles and to understand the ability of key wear-resistant parts to resist fatigue failure due to turbulence,weather,road conditions and other reasons during driving,low-cycle fatigue tests were carried out with a hot-rolled TRIP wear-resistant steel plate NM300 with a thickness of 3.5mm.The fatigue performance of NM300 under different strain amplitudes was studied,the characteristic curve of cyclic stress response and the stress-strain hysteresis loop were obtained,the Masing effect of NM300,the relationship between cyclic stress and inelastic strain,and the relationship between cyclic strain and fatigue life were studied,and the low-cycle fatigue fracture mechanism of NM300 under different strain amplitudes was analyzed.The experimental results show that NM300 exhibits cyclic hardening under the control of low strain amplitude,and cyclic softening under the control of high strain amplitude,and the cyclic response stress of NM300 increases gradually with the increase of strain amplitude.When the strain amplitude is less than 0.37%,the cycle life can reach more than 104 times.When the strain amplitude is less than 0.19%,the cycle life can reach more than 105 times.The fatigue fracture of NM300 has typical fatigue fracture characteristics,which can be divided into three zones:fatigue source zone,crack propagation zone and transient fracture zone.With the increase of strain amplitude,the crack propagation zone area decreases and the surface becomes rough.The fracture forms of fatigue fracture are mainly intergranular brittle fracture and intergranular ductile fracture.According to the service conditions of hot-rolled wear-resistant steels,the fatigue performance is considered to be excellent.

关 键 词：热轧耐磨钢 低周疲劳性能 迟滞回线 断口形貌 

分 类 号：TG142.72[一般工业技术—材料科学与工程]