Numerical analysis of the thermally induced damage in remote laser cut carbon fibre reinforced polymers

Abstract

Remote laser cutting in carbon fibre reinforce polymers is a promising machining technology which can reduce the main drawback in laser cutting, the heat affected zone. This contribution presents a two-step modelling approach for the simulation of remote laser cut carbon fibre reinforce polymers, consisting of a damage model for the initially intact material and a model for the thermally damaged material. The static damage behaviour was modelled with the Pinho material model [1], which stands out due to its physically based failure criteria. Initial thermal damages caused by the heat input were modelled with the damage parameters of the Pinho model. The dimensions of the heat affected zone are taken from polished micro sections of the material around the cutting edge. As a numerical example, comparative tensile tests of milled and laser cut open hole specimens were simulated. The advantage of these specimens is the notch effect around the holes in the heat affected zone, which amplifies the differences between the two cutting technologies.

Analysis of the remote laser cutting process induced damage in carbon fibre reinforced polymers with cutting process simulations

“…Laser cutting, as a fast, versatile and wear-free cutting technology has the drawback of a heat affected zone (HAZ), an area where the matrix is evaporated or chemically decomposed. As [1] and [2] stated, the HAZ strongly affects the mechanical properties of CFRP and thus needs to be considered in the structural analysis. Possible ways to identify the HAZ dimensions are 1D heat conduction calculations as presented in [3] or the identification from micro-sections of the cutting gap [4].…”