Effect of gas pressure on Al coatings by cold gas dynamic spray

Al coatings by cold gas dynamic spray (CGDS, or Cold Spray) technique with pressure condition were investigated. The relatively soft Al has been coated at low gas pressure condition (0.7 MPa) with severe plastic deformation. However, the Al particles in the coatings coated at the higher pressure conditions (1.5 MPa, 2.5 MPa) were not severely deformed. In the case of hardness, the coating of Al at low pressure condition had higher hardness because of work hardening (peening effect) resulted from bounced-off Al particles (0.7 MPa). Therefore, it was found that the gas pressure as a processing parameter could have an influence on Al coating's properties. (c) 2007 Elsevier B.V. All rights reserved.