2019 Volume 56 Issue 4 Pages 149-153
Cold spraying has been developed as a high-quality metallic coating process. On the other hand, cold spraying of ceramic material is still difficult due to a lack of its ductility which is required for this process. There are several reports to fabricate ceramic coatings through this process. However, the deposition mechanism of cold-sprayed ceramic material has not yet been clarified. This study aims to clarify the importance of the microstructure of feedstock powder material on the formation of thick ceramic coating through cold spray process. Yttria powders with different specific surface area were prepared and coldsprayed onto aluminum alloy substrate. Furthermore, the microstructure of feedstock powder materials was carefully observed. The results revealed that the higher specific surface area enhanced the deposition of cold-sprayed ceramic particles and enabled to fabricate thick coatings. Fine primary particles agglomerated with high specific surface area and porous structure can be the most important factor to realize the fabrication of thick ceramic coatings by cold spray.