Effects of different mould coatings on polymer filling flow in thin-wall injection moulding

Injection moulding of parts having high flow length/thickness ratio is a challenging task for both micro and packaging applications. In the filling phase, high-speed injection can cause a raise of cavity pressure, which prevents the complete replication of the mould geometry. Therefore, in this paper, the effects of three mould coatings, such as aluminium oxide, diamond-like carbon and silicon oxide, were investigated. In particular, the filling of a representative micro-part was studied as a function of mould coating, injected polymer and different process parameters, in order to identify the effects of heat conduction and wall slip related to the coatings.