Temperature rise induced by a rotating or dithering laser beam

Abstract

We study the maximum temperature rise induced by a rotating or dithering Gaussian laser beam on a semi-infinite body. An analytical solution is obtained by solving the transient three-dimensional heat equation in a semi-infinite domain with insulating surface. The effect of rotating or dithering frequency on maximum temperature rise is quantitatively investigated for stainless steel and carbon nanotube-alumina composites. It is found that the maximum temperature rise can be reduced by increasing the frequency of the rotating or dithering beam and by increasing the radius of the rotating or dithering trajectory. For a fixed frequency, the maximum temperature rise induced by a rotating beam is lower than the one induced by a dithering beam. Finally, we give the asymptotic solution of the temperature rise for large frequency of a rotating Gaussian beam.