2014 Volume 51 Issue 3 Pages 77-81
In the thermal spray process, feedstock materials are heated to above those melting points. Therefore the deterioration of the characteristics such as oxidation, thermal alteration and phase transformation of the feedstock materials becomes a problem. The solid particle deposition processes such as cold spray and aerosol deposition are expected as a way of preventing this problem. Cold spray uses mainly a soft metal powder as the feedstock powder material and the powder material deposits in an atmospheric condition. On the other hand, aerosol deposition uses mainly a ceramic fine powder as the feedstock powder material and the powder material deposits in a vacuum condition. Both processes are based on a collision of solid particle. Therefore it seems that there is a common deposition mechanism. In this study, the deposition mechanism of solid particle was investigated by microscopic observation and elemental analysis. A simple mixture of aluminum and copper was used as feedstock material in cold spray and aerosol deposition. The observation confirmed a metallic bonding at particle interface in both deposition processes. However, the metallic bonding is not a main at interface in aerosol deposition compare with the cold spray process. The bonding through the oxide layer has been suggested.