Three‐dimensional modelling of intergranular fatigue failure of fine grain polycrystalline metallic MEMS devices

摘要: This paper presents a 3D finite element model to investigate intergranular fatigue damage of microelectromechanical systems (MEMS) devices and account for the effects topological randomness material microstructure on lives. The topology MEMS grain structures is modelled using randomly generated Voronoi tessellations. Continuum Damage Mechanics used progressive degradation due fatigue. A new micro-grain debonding procedure developed consider both crack initiation propagation stages. then variability in life cantilever devices. Three different types are considered: (1) disorder random shapes sizes grains, (2) variation properties considering normally (Gaussian) distributed elastic modulus (3) defects or internal voids. stress–life results obtained good agreement with experimental data. progression overall pattern from microcantilever beam consistent empirical observations.