Influence of thermo-mechanical loads on the lifetime of plastic inserts for injection moulds produced via additive manufacturing

This paper investigates the dependence of the functional life of additively manufactured plastic insert moulds on occurring shear stresses and temperatures during the injection moulding process. As a first step, a dedicated plastic insert is designed that allows for experimentally simulating different shear rates and thermal loads of the injected polymer in a single shot, allowing to assess their effect on the functional lifetime of the insert. Then, a numerical optimisation pipeline is designed to allow the optimisation of the injection moulding parameters, which is obtained by combining Noesis Optimus with Autodesk Moldflow. To enhance the accuracy of the numerical optimisation results, several important thermal mould characteristics are verified using differential scanning calorimetry (DSC) and thermo-mechanical analysis (TMA). An experimental campaign aims at validating the optimised parameters and assesses the occurring damage to the mould material. Finally, flow orientation stemming from numerical results is validated by images generated by a scanning electron microscope (SEM) based on a fibre reinforced material, injected in an additive manufactured and a machined tool steel mould.status: accepte