Thermal behaviour of additively manufactured injection moulding inserts

Injection moulding using inserts from vat polymerization, an additive manufacturing technology, has been investigated for pilot production and rapid prototyping purposes throughout the past years. Experiments have used a standard mould is equipped with additively manufactured inserts in a rectangular shape of (20 x 20 x 2.7) mm3 produced with vat photo polymerisation.

While the lifetime compared to conventional materials such as brass, steel, and aluminium, is reduced, the prototyping and design phase can be shortened significantly by using flexible and cost-effective additive manufacturing technologies. While crack propagation has been significantly reduced, further developments become possible, such as multi-scale injection moulding inserts with dimensions of (80 x 60 x 10) mm3 where an insert with larger outside dimensions and micro features on the surface is used during the manufacturing process.

Higher manufacturing volume still exceed the capability of additively manufactured inserts, which are overruled by the stronger performance of less-flexible but stronger materials. This contribution discusses the heat transportation within the inserts made from a thermoset material, brass, steel, and ceramic material.

It therefore elaborates on the possibilities of injection moulding as well as the thermal challenges connected with the use of polymer inserts. They are an essential part for further calibrations of the injection moulding process.