压力容器用耐高温马氏体钢的疲劳裂纹扩展速率  

Fatigue crack propagation rate of high temperature resistant martensitic steel for pressure vessel

作　　者：杨昊 张鸿涛 梁恩溥 夏明旗 史超 徐乐[1] 刘鑫 王毛球[1] Yang Hao;Zhang Hongtao;Liang Enpu;Xia Mingqi;Shi Chao;Xu Le;Liu Xin;Wang Maoqiu(Research Institute of Special Steels,Central Iron and Steel Research Institute Co.,Ltd.,Beijing 100081,China;North Hua'an Industrial Group Co.,Ltd.,Qiqihar Heilongjiang 161000,China;Army Equipment Department in Shenyang Regional Military Representative Bureau in Baotou Regional Situation Representative Office,Baotou Inner Mongolia 014000,China;Inner Mongolia North Heavy Industry Group Co.,Ltd.,Baotou Inner Mongolia 014000,China)

机构地区：[1]钢铁研究总院有限公司特殊钢研究院,北京100081 [2]北方华安工业集团有限公司,黑龙江齐齐哈尔161000 [3]陆军装备部驻沈阳地区军事代表局驻包头地区军事代表室,内蒙古包头014000 [4]内蒙古北方重工业集团有限公司,内蒙古包头014000

出　　处：《金属热处理》2025年第3期174-182,共9页Heat Treatment of Metals

摘　　要：对PCrNi3MoV、25Cr3Mo3NiNbZr和20CrNiMo2VNb高温马氏体钢进行25℃和700℃下的拉伸及疲劳裂纹扩展试验,研究了压力容器用钢的疲劳裂纹扩展行为。结果表明,室温下,3种试验钢的强度相当,应力强度因子水平(ΔK)为60 MPa·√m时,疲劳裂纹扩展速率(d a/d N)分别为1.05×10^(-3)、8.80×10^(-5)和7.73×10^(-5) mm/cycle。20CrNiMo2VNb钢的室温疲劳裂纹扩展速率低,这是由于其亚结构大角度晶界占比最大,为81.46%。700℃高温下,应力强度因子水平ΔK为30 MPa·√m时,3种试验钢的疲劳裂纹扩展速率分别为1.58×10^(-3)、3.78×10^(-4)和3.89×10^(-5) mm/cycle。微观组织与高温强度对比分析发现,20CrNiMo2VNb钢700℃抗拉强度最高是导致其疲劳裂纹扩展速率低的主要原因。基于Paris模型,建立了耐高温马氏体钢的疲劳裂纹扩展速率与力学性能的量化关系,为20CrNiMo2VNb钢的后续疲劳裂纹扩展研究提供理论支撑。Tensile and fatigue crack growth tests were conducted on high temperature martensitic steels PCrNi3MoV,25Cr3Mo3NiNbZr and 20CrNiMo2VNb at 25℃and 700℃to investigate the fatigue crack growth behavior of pressure vessel steels,respectively.The results show that at room temperature,the strength of the three tested steels is fairly the same.When the stress intensity factor level(ΔK)is 60 MPa·m,the fatigue crack growth rates(d a/d N)are 1.05×10^(-3),8.80×10^(-5),and 7.73×10^(-5) mm/cycle,respectively.The fatigue crack growth rate of the 20CrNiMo2VNb steel at room temperature is the lowest,which is attributed to its largest proportion of substructure high-angle grain boundaries,reaching 81.46%.At 700℃,when the stress intensity factor levelΔK is 30 MPa·m,the fatigue crack growth rates of the three tested steels are 1.58×10^(-3),3.78×10^(-4),and 3.89×10^(-5) mm/cycle,respectively.Through the comparative analysis of the microstructure and high temperature strength,it is found that the highest tensile strength of the 20CrNiMo2VNb steel at 700℃is the main reason for its low fatigue crack growth rate.Based on the Paris model,a quantitative relationship between the fatigue crack growth rate and mechanical properties of high temperature resistant martensitic steel is established,which provides theoretical support for the subsequent research on the fatigue crack growth of the 20CrNiMo2VNb steel.

关 键 词：耐高温马氏体钢 疲劳裂纹扩展速率 Paris曲线 应力强度因子 

分 类 号：TG142.1[一般工业技术—材料科学与工程]