氢对30CrMo钢拉伸和超低周疲劳性能的影响  

Effect of hydrogen on tensile and ultra-low cycle fatigue properties of 30CrMo steel

作　　者：吴鑫 付磊 张应迁 罗云蓉 张云波 官彦兵 WU Xin;FU Lei;ZHANG Yingqian;LUO Yunrong;ZZHANG Yunbo;GUAN Yanbing(College of Mechanical Engineering,Sichuan University of Science and Engineering,Zigong 643000,Sichuan,China;College of Civil Engineering,Sichuan University of Science and Engineering,Zigong 643000,Sichuan,China)

机构地区：[1]四川轻化工大学机械工程学院,四川自贡643000 [2]四川轻化工大学土木工程学院,四川自贡643000

出　　处：《钢铁研究学报》2024年第3期378-388,共11页Journal of Iron and Steel Research

基　　金：国家自然科学基金面上资助项目(52171062)。

摘　　要：主要研究了氢对30CrMo钢的超低周疲劳性能和力学行为的影响。用0.5 mol/L的H_2SO_4溶液对试验钢进行电化学充氢1和4 h,然后采用轴向位移控制模拟地震载荷进行超低周疲劳试验和拉伸试验,获得了循环应力应变响应、滞回行为及应变-寿命等关系。结合扫描电子显微镜(SEM)进行断口形貌观察,分析其超低周疲劳断裂机制。结果表明:充氢1和4 h后试验钢的抗拉强度强度由原来的681 MPa提升到689和698 MPa;其断裂伸长率由原来的33%下降到29%与19%,氢的浓度越高塑性下降越明显;电化学充氢明显削弱了试验钢的抗疲劳性能,预充氢1和4 h后试验钢的寿命分别下降了33.8%~40.7%和65.3%~69.8%;充氢对试验钢的循环响应特征及Masing特性无明显影响;长时间充氢会使30CrMo钢的裂纹扩展区面积减小并加快其裂纹扩展速率。The influence of hydrogen on the ultra-low cycle fatigue performance and mechanical behavior of 30CrMo steel was investigated in this study. The experimental steel was subjected to electrochemical hydrogen charging in a 0.5 mol/L H_2SO_4 solution for 1 and 4 h, respectively, subsequently, ultra-low cycle fatigue tests and tensile tests were carried out under simulated earthquake load-controlled axial by displacement to obtain cyclic stress-strain responses, hysteresis behavior, and strain-life relationships. Combining with scanning electron microscope(SEM), fracture surface morphology was observed to analyze the ultra-low cycle fatigue fracture mechanism. The results show that the tensile strength of the experimental steel increases from 681 MPa to 689 and 698 MPa after 1 and 4 h hydrogen filling;the fracture elongation has decreased from 33% to 29% and 19%, and the reduction in ductility becomes more severe with higher hydrogen concentration. Electrochemical hydrogen charging significantly weakens the fatigue resistance of the experimental steel. The fatigue life of the test material decreased by 33.8% to 40.7% and 65.3% to 69.8% after pre-charging with hydrogen for 1 and 4 h, respectively. Hydrogen charging had no significant impact on the cyclic response characteristics of the experimental steel in relation to Masing behavior. Prolonged hydrogen charging reduced the crack propagation zone area and accelerated the crack propagation rate of the 30CrMo steel.

关 键 词：30CrMo 电化学充氢 超低周疲劳 力学性能 

分 类 号：TG142.4[一般工业技术—材料科学与工程]