Hot and cold cleaning methods: CO2 and Nd:YAG laser ablation, sodium hydride immersion and CO2 cryoblasting

Cleaning of RTM moulds – the problem! The removal of loosely bound or weakly adsorbed contamination from surfaces can usually be achieved using conventional cleaning methods such as solvents or proprietory aqueous-based cleaning solutions. However, the removal of fully crosslinked material which might be strongly adsorbed or chemisorbed onto surfaces, such as paints or adhesives, presents a much greater challenge. Similarly, residual epoxide resins remaining on the inside surfaces of resin transfer mould (RTM) tooling post curing are strongly adhered to the mould surface and need to be removed so that the mould can be reused. The mould materials are typically steel or nickel but may be compositebased. Conventional methods cannot fully remove residual epoxide material without the use of hazardous chemicals and mechanical removal can easily result in damage to the underlying mould which may compromise its reuse. Therefore, a number of novel cleaning solutions have been investigated to address the challenging problem of how to remove fully crosslinked epoxide resins from RTM mould surfaces.