Manufacturing of Cu Repair Coating Material Using the Kinetic Spray Process and Changes in the Microstructures and Properties by Heat Treatment

This study is a basic research for repair material production which manufactured a Cu repair coating layer on the base material of a Cu plate using kinetic spray process. Furthermore, the manufactured material underwent an annealing heat treatment, and the changes of microstructure and macroscopic properties in the Cu repair coating layer and base material were examined. The powder feedstocks were sphere-shaped pure Cu powders with an average size of $27.7{\mu}m$. The produced repair coating material featured $600{\mu}m$ thickness and 0.8% porosity, and it had an identical ${\alpha}$-Cu single phase as the early powder. The produced Cu repair coating material and base material displayed extremely high adhesion characteristics that produced a boundary difficult to identify. Composition analysis confirmed that the impurities in the base material and repair coating material had no significant differences. Microstructure observation after a $500^{\circ}C/1hr$. heat treatment (vacuum condition) identified recovery, recrystallization and grain growth in the repair coating material and featured a more homogeneous microstructure. The hardness difference (${\Delta}H_v$) between the repair coating material and base material significantly reduced from 87 to 34 after undergoing heat treatment.

Kinetic spray 공정을 이용한 Cu repair 코팅 소재 제조 및 열처리에 따른 미세조직과 물성 변화