Several kinds of Calculation Methods on the Crack growth Rates for Elastic-Plastic Steels

摘要

Research interdependent correlations among various calculations models,relationship between their calculations parameters,and relationship between their materials constants in equations on strengths and life predictions,which are elastic-plastic steels with cracks.Thereby obtain and suggest to adopt several new calculations models and their calculations methods on crack propagation rates,which are respectively suitable for calculations of crack propagation rates under different stress ratio loading,or are suitable for calculations under symmetrical and unsymmetrical cyclic loadings,the work stresses less than or greater than the yield limit.Also the material constants B2 in new models are defined as comprehensive material constants and give also out their physical meaning and geometric significances that are having a function relation with other parameters.Moreover provide yet a calculation example of crack propagation rate.Anticipate that the works will be having practical significances for fatigue-damage-fracture tests to save experimental times,fund inputs and to expand engineering applications.