Study of the machining induced damage in UD-CFRP laminates with various fibre orientations : FE assessment

Finite elements (FE) provide an excellent and low-cost approach in the assessment of composite machining induced damage. This article is focused on the evaluation of the damage underlying the machined surface through the development of a novel 3D FE model in composite machining. Sub-surface damage of UD-CFRP with fibre orientations from 0o to 90o is evaluated. An algorithm to assess composite damage evolution and chip formation is inserted via user-defined subroutine. Damage initiation is determined using Hashin’s failure criteria for fibre damage modes, while matrix damage modes are assessed via Puck’s failure criteria. Subsequent damage evolution is modelled using an energy-based linear damage degradation law. Numerical results reveal relevant advances in the prediction of the damage induced underlying the machined surface for fibre orientations from 60o to 90o obtained in previous investigations