ASSESSMENT OF INTRINSIC CREEP RESISTANCE EVOLUTION BASED ON THE RESULTS OF CONSTANT-LOAD CREEP TESTS

In the present study a method to assess the intrinsic creep resistance evolution by using data of constant load creep tests is proposed. The investigation has been performed on the austenitic steels X6 CrNi 16 11 and X8 CrNiMoNb 16 16. To develop the constitutive equation describ ing the intrinsic creep resistance evolution a simple structural mecha nical model has been used. The applied model is based on a modificatio n of the Levy-Mises equation for plasticity to consider creep time eff ects. The proposed model has been verified experimentally. The experim ental creep resistance evolution curves have been derived with the aid of strain transient dip test performed in transient, steady state and accelerated creep stage.