Failure analysis and damage modeling of precipitate strengthened Cu-Ni-Si alloy under fatigue loading

Failure analysis and damage evolution in precipitation hardened Cu-2.5Ni-0.6Si alloy are investigated in this study. Firstly, experimental fatigue tests were performed to determine the S-N curve of the material. Then, based on the results of fatigue tests, we have modeled the damage using four linear and cumulative models. The intersection of damage-reliability curves allowed to define three stages of damage during the life cycle for various loading levels. The life fraction Pp reveals the stage of slow crack propagation where a preventive action must be adopted to ensure the proper functioning of the structure. The life fraction Pc corresponds to the stage of sudden crack propagation when the damage becomes uncontrollable. (C) 2018 The Authors. Published by Elsevier B.V.