Improved cold gas-dynamic spraying process

摘要

A cold gas-dynamic spraying process comprising spraying a carrier gas containing small diameter particulates on to a substrate thereby coating the substrate in a spraying chamber (25), the process comprising the steps of removing the particulate-containing carrier gas from the chamber; directing the gas into a ceramic filter (30), thereby separating the gas from the particulates; removing the particulate-free carrier gas and the particulates from the ceramic filter; analysing the purity of the particulate-free carrier gas; and directing the particulate-free carrier gas into a multi-valve assembly (40).