H. Y. Lee, Y. H. Yu, S. H. Jung, S. Y. Lee, K. H. Ko, Ajou University, Suwon 443 749, South Korea
Soft metal (Al) and hard ceramic (Al2O3) composite coatings were prepared on Si and Al substrate by cold spray. The powder compositions of metal (Al) and ceramic (Al2O3) having different size and agglomerations were varied into 10:1 wt% and 1:1 wt%. The hard ceramic powders were successfully incorporated into the soft metal matrix of Al. It was found that crater formation which is typical characteristic signature of cold spray could be affected by final fragmented size of hard particles. Also, when the large hard particles were employed, the deep and big craters were generated at the interface between films and hard substrates. In the case of pure soft metal coating such as Al on hard substrate, it is very hard to get proper adhesion due to lack of crater formation. Therefore, the composite coating would have certain advantages.
Summary: Al-Al2O3 composites using different particle composition and forms were successfully coated on Si and Al substrate by cold spray. There are good possibilities that cold spray coating of hard materials incorporated with soft Al can be successfully performed.
