Process chain for replicating bio inspired micro structured surfaces

Bio inspired surfaces targeting functional characteristics such as anti reflectivity, self cleaning effects or a drag reduction are of a significant interest to industry. In this research, two process chains are investigated for the mass production of so-called shark skin structured surfaces. Due to their drag reduction properties, such bio inspired surfaces are of relevance to a number of applications in which particular aqua and aerodynamic characteristics are required. The design of the shark skin structure relies on a bio-mimetic analytical model to generate the 3D surface model necessary to achieve the targeted surface functionality. The process chains presented combine laser ablation as a method for micro structuring masters for high throughput replication employing injection moulding. In particular, two process chains that rely on respectively micro second (ms) and pico second (ps) laser ablation systems to pattern mould inserts were investigated. Then, they were integrated into a tool for micro injection moulding and the replication results obtained from the two different mould inserts were compared to study the viability of the proposed process chains. The results show that micro structures can be replicated successfully in both cases, but further work is required to optimise the replication process