Research on fatigue crack growth test of 42CrMo steel for pitch bearing and crack growth characteristics of bolt hole
Based on the 42CrMo steel used for pitch bearings of wind turbine,the compact tensile specimen(CT specimen)from the stress concentration area of pitch bearing was sampled.Fatigue crack growth tests of CT samples were carried out with different loads and stress ratios,and data of Paris fatigue crack growth model was fitted for the crack growth process.The Paris model parameters of C and m were obtained by fitting the test data.ABAQUS and FRANC3D software were used for co-simulation,and the number of cycles and the crack length with different stress ratios and different loads obtained from the test and simulation were compared,which are in good agreement.By modeling the dangerous parts of pitch bearing of wind turbine,the submodel of bolt hole of pitch bearing was estab-lished,the fatigue crack growth was simulated by establishing the initial crack at the dangerous parts,and the fatigue crack growth laws with different length-depth ratios and different angles were studied.The results show that with the increase of length-depth ratio a/b,the number of cycles required decreases when the crack growth is the same length.The shape and angle of the initial crack have great influ-ence on the crack growth law.
pitch bearingfatigue crack growthstress intensity factorbolt holefinite element
NETL
NSTL
万方数据
