Cold gas dynamic spraying of high strength copper

A process for forming an article, such as a combustion chamber liner, comprises the steps of providing a mandrel (10) formed from a material, such as an aluminum containing material, having a net shape of the article to be made, depositing a powdered metal material (12) onto the mandrel (10) without melting the powdered metal material, and removing the material forming the mandrel to leave a free standing monolithic article. In a preferred embodiment of the present invention, the powdered metal material comprises powdered GRCop-84. Alternatively, the powdered metal material may be GRCop-42.