Parametric study of metal droplet deposition and solidification process including contact resistance and undercooling effects

The effects of process parameters on metal droplet spreading and solidifica tion are investigated numerically. The parameters include the impinging vel ocity, contact resistance between the droplet and substrate, and degree of undercooling associated with rapid phase change. A simplified model is adop ted to describe the splat size evolution and energy equations for the liqui d, solidified layer, and substrate are simultaneously solved to analyze hea t transfer processes during solidification. The energy equations are couple d by boundary conditions such as contact resistance and undercooling in a r egularized calculation domain formed by means of algebraic grid generation. The results reveal that impinging velocity and contact resistance have str ong effects on both final splat size and solidification time. The effects o f undercooling are not significant unless the nucleation temperature is low in relation to the initial liquid superheating. (C) 2001 Elsevier Science Ltd. All rights reserved.