Residual Life Estimation Under Low-Cycle and Thermo-Mechanical Fatigue Conditions: Proposal of a Dedicated Numerical Code

A brief description of the main guidelines of the most common literature damage models is reported; in particular two uniaxial and five multi-axial damage models have been individuated from literature, which can be all used determining five parameters only, with a decisive advantage in terms of experimental effort. A Matlab®-based fatigue code has been purposely developed with the aim to receive in input the stress-strain data obtained by finite element analysis or experimentation and the constitutive parameters of the damage models, providing as output directly the residual fatigue life of the component under investigation. The paper presents the pivotal features of a numerical code, named FAST-Life, purposely developed to make the usage of these literature damage models easy and fast, and summarizes the predictions achieved with respect the estimation of the residual life of a commercial exhaust manifold made by ductile Si-Mo-Cr cast iron.