Laser consecutive pulse heating and phase change: Influence of spatial distribution of laser pulse intensity on melting

Laser consecutive pulse heating of solid surface and the influence of the laser pulse parameter on the melting and mushy zone formation in the irradiated region are investigated. The laser pulse parameter (β) defines the spatial distribution of the laser pulse power at the irradiated surface; in which case, β = 0 represents the Gaussian profile while β = 1 corresponds to the ring type of laser power distribution with the peak intensity away from the center (symmetry axis). β is set in such a way that the energy content in each pulse with different β values becomes the same. The control volume approach is used when modeling the heating and phase change processes. The laser pulse parameter is selected to alter the laser power intensity distribution across the irradiated surface while modifying the location and magnitude of the laser peak power intensity at the irradiated surface. It is found that the laser pulse parameter alters the sizes of the melting and mushy zones in the surface region.