| Summary: | Gas and Fe-0.8 wt.% C droplet dynamics during electric arc spraying have been characterised using particle image velocimetry (PIV). This study has shown that the flow of N-2 atomising gas was well-collimated, with an exit velocity of 255 m s(-1), decaying to 75 m s(-1) at an axial distance of 150 rum, where the jet diameter was similar to50 mm. The presence of atomised steel droplets increased spray divergence. Droplet mode velocity measurements equalled the gas-only velocity measurement of similar to 120 m s(-1) at an axial distance of 95 mm, and then further increased to 135 m s(-1) at 150 mm. Close to the substrate, droplet splashing dominated the flow field with upward and then lateral flow of splashed droplets. In the presence of a vertical step feature, the flow field became complex, with some splash droplets having trajectories that caused secondary deposition on the vertical step wall. (C) 2004 Elsevier B.V. All rights reserved.
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