The influence of microdamage on the elastic characteristics of metastable austenitic steels under fatigue

The relationship between the elastic moduli and the change in the phase composition and microdamage of metastable austenitic steel under fatigue was studied. An algorithm for calculating microdamage is developed taking into account the influence of a complex of factors on the elastic characteristics – the formation of strain-induced martensite, which has a contrast of elastic moduli with the material matrix, and changes in the crystallographic texture. A high correlation between the normalized value of microdamage relative to its critical value, corresponding to the appearance of a macrocrack and the damage calculated using the Palmgren–Miner linear summation of damage, which is widely used to assess the service life characteristics of steels.