Mathematical modeling of melting during laser materials processing

Melting is encountered in almost all laser materials processing. This article deals with a one-dimensional heat conduction problem to investigate the melting rate during laser materials processing. The problem is solved approximately to obtain a correlation among melt depth, power density, and laser irradiation time. Based on this correlation, the dynamics of melting, a relationship between the melt depth and power density and an average melting velocity are expressed by simple analytic formulas. These expressions are further simplified for high power densities (I greater than or equal to 10(9) W/m(2)). The times to reach the melting and boiling temperatures at the surface of the workpiece are also calculated. (C) 1997 American Institute of Physics.