Study on Creep Damage Behaviors of Ni-Based Alloy C276

High temperature creep tests were carried out for Ni-based alloy C276 at 650℃,700℃and 750℃,which is one of the candidate materials for the fuel cladding of the supercritical water reactor.Methods of damage mechanics were adopted to calculate and analyze these data.Damage factors calculated by Kachanov formula and Norton formula based on θ projection method were compared.The results show that the damage factors about the material are similar at the three temperatures according to Kachanov formula.The predicted creep curves calculated by θ projection method have a close agreement with the experimental data.The damages calculated by Norton formula start at about 0.3~0.4 lifetime,and the damage factors calculated by Kachanov formula are relatively conservative.