Investigation of surface treatment effects in micro-injection-moulding

Micro-injection-moulding as a replication method is one of the key technologies for micro-manufacture. An important stage in micro-injection-moulding which can affect the accuracy and mechanical properties of the produced components is part de-moulding. During this stage, part-mould forces can cause a variety of defects to micro-parts, including stress marks, deformation, fracture and stretching of the polymer structures. Therefore, in this paper, the effects of different surface treatments on the de-moulding behaviour of parts with micro-features are investigated. In particular, the de-moulding of a representative micro-part was studied as a function of two different tool coatings, diamond-like carbon and silicon carbide, in combination with four process parameters, employing the design of experiment approach. In addition, the results obtained using different combinations of process parameters were analysed to identify the best processing conditions in regards to de-moulding behaviour of polycarbonate and acrylonitrile butadiene styrene micro-parts when utilising these two coatings.