Precision Mould Making – From Macro to Micro

Abstract

Nowadays several qualified technologies have been established for the manufacturing of precision moulds. The fields of application can mainly be divided into moulds for non-optical and optical components. For optical moulding inserts the development goes from basic rotational symmetric geometries to complex surfaces like steep aspheres and freeforms which can additionally be overlaid with microstructures. The moulded components require a figure accuracy in the (sub-) micrometer and surface roughness in the nanometer range while moulds for replication also need advanced materials with high surface integrity. Here, diamond machining processes, e.g. diamond turning and milling as well as precision grinding and polishing are necessary for the manufacturing of precision moulding inserts from various materials. Depending on the material and application of the applied part to be replicated different replication techniques are used like injection moulding of plastics, hot embossing and precision moulding of optical glasses. For non-optical applications the current technical progress is driven by miniaturized products which are typically produced in mass production by replication techniques like hot embossing or metal forming. Each of these processes requires specific properties of the mould. Therefore, the surface topography and tribological conditions are of particular importance.