含缺陷的30NiCrMoV12车轴钢的多变量疲劳性能研究

Multivariate Fatigue Performance Study of 30NiCrMoV12 Defective Axles

车轴遭受异物冲击缺陷存在多种形式,其中棱角冲击对车轴疲劳性能影响较大,会加速车轴的失效。为研究棱角冲击缺陷对车轴疲劳极限的影响,针对30NiCrMoV12车轴钢,采用软件模拟与疲劳试验相结合的方法,借助ABAQUS对冲击缺陷区域进行应力场分析,对预制好的缺陷车轴试样进行疲劳试验,依据试验结果采用近似欧文单侧公差极限法拟合各试样组疲劳P-S-N曲线,得到相应的疲劳极限。根据各试样组的疲劳试验结果预测全尺寸车轴疲劳极限。考虑冲击缺陷深度的分散性,对缺陷深度和全尺寸车轴疲劳极限两参数进行拟合。最后基于EI-HADDAD公式,建立含棱角冲击缺陷的30NiCrMoV12车轴钢的多变量疲劳极限预测模型。采用该模型能够快速预估含不同尺寸棱角缺陷的全尺寸车轴疲劳极限。

There are many forms of foreign object impact defects on the axle,among which the angular impact has a greater impact on the fatigue performance of the axle and will accelerate the failure of the axle.In order to study the influence of angular impact defects on the fatigue limit of the axles,for the 30NiCrMoV12 axle steel,the combination of software simulation and fatigue test is adopted,the stress field analysis of the impact defect area is carried out with the help of ABAQUS,the fatigue test is carried out on the prefabricated defective axle sample,and the fatigue P-S-N curve of each sample group is fitted according to the test result of the approximate Owen one-side tolerance limit method,and the corresponding fatigue limit is obtained.The fatigue limit of the full-size axle is predicted based on the fatigue test results of each specimen group.Considering the dispersion of the impact defect depth,the two parameters of the defect depth and the fatigue limit of the full-size axle are fitted.Finally,based on the EI-HADDAD formula,a multivariate fatigue limit prediction model of 30NiCrMoV12 axle steel with angle impact defects is established.The model can be used to quickly predict the fatigue limit of full-size axles with different sizes of angular defects.