【摘要】 对EH40钢进行疲劳裂纹扩展速率测试试验,测定一系列裂纹尺寸ai及所对应的疲劳荷载次数Ni和裂纹嘴张开位移(CMOD)。通过a-N曲线,运用ORIGIN软件的微分功能得到试样的裂纹扩展速率。通过CMOD与裂纹尖端张开位移(CTOD)的对应关系,得到裂纹扩展过程中的一系列CTOD的值δ。通过数据分析,表明裂纹扩展速率与裂纹尺寸存在指数关系,并与δ存在线性相关。在此基础上,提出新的裂纹扩展速率公式,避免了Paris公式的局限性。更多还原

【Abstract】 In this paper,EH40 steel fatigue crack growth rate test was conducted.A series of crack size(ai)and the number of fatigue loads(Ni)were measured,as well as CMOD.By making a-N curves,the differential function of ORIGIN software was used to obtain the crack growth rate of the samples.Through the corresponding relationship between CMOD and CTOD,a series of CTOD values during crack propagation was obtained.The results of data analysis indicated that there is an exponential relationship between the crack growth rate and the crack size.It also showed that there is a linear correlation between the crack growth rate and CTOD value.The new crack growth rate formula was put forward so as to prevent the limitations of Paris formula.更多还原