Fatigue Life Prediction Considering Continuum Damage Mechanics

Non-Linear kinematic hardening and isotropic hardening for modeling low cycle fatigue is done. Also. Multiaxial Non-linear cumttlative fatigue damage model based oncontinuum damage mechanics (CDM) is considered to predict the maximum stress - fatigue life for different loading paths. The ability of the presented models to describe all the main features of fatigue damage and cyclic plasticity, are discussed. The under study materials are 7075-T6 and 6()6l-T6 aluminum alloy that is widely used in aerospace. marine. and transport industry. The material constants of the used model for 7075-T6 and 6061-T6 alloys are obtained based on two different stress ratio for CDM model.lhe C DM model is applied for different loading paths including proportional and non-proportional paths. Obtained results show that using CDM would give conservative and acceptable results. The use of Chaboehe-Lemaitre fatigue damage model to predict fatigue lives of specimens and mechanical components is a case that researchers start to study on it ill recent years. Also, the use of this Model to predict fatigue lives for different loading paths has not investigated well.

Keywords:

continuum damage mechanics , cyclic plasticity , loading paths , fatigue life , aluminum alloy