Replicative manufacturing of metal moulds for low surface roughness polymer replication

Tool based manufacturing processes like injection moulding allow fast and high-quality mass-market production, but for optical polymer components the production of the necessary tools is time-consuming and expensive. In this paper a process to fabricate metal-inserts for tool based manufacturing with smooth surfaces via a casting and replication process from fused silica templates is presented. Bronze, brass and cobalt-chromium could be successfully replicated from shaped fused silica replications achieving a surface roughnesses of R(q) 8 nm and microstructures in the range of 5 µm. Injection moulding was successfully performed, using a commercially available injection moulding system, with thousands of replicas generated from the same tool. In addition, three-dimensional bodies in metal could be realised with 3D-Printing of fused silica casting moulds. This work thus represents an approach to high-quality moulding tools via a scalable facile and cost-effective route surpassing the currently employed cost-, labour- and equipment-intensive machining techniques.