A LASER SUCCESIVE PULSE HEATING OF A MOVING SLAB - AKINETIC THEORY APPROACH

Laser successive pulse heating of engineering surfaces becomes fruitfu l for thermal treatment of the engineering parts. In this case, therma l integration of the surface temperature becomes essential. In the pre sent study, a 3-dimensional mathematical model allowing a laser succes sive pulse heating is introduced using an electron kinetic theory appr oach. A laser beam is considered to scan the workpiece surface with a constant velocity. However, the energy equation so derived is in the f orm of an integro-differential equation which does not yield an analyt ical solution. Therefore, a numerical method using an explicit scheme is introduced to obtain the temperature profiles. It is found that ene rgy gain of the lattice site atoms through successive electron-phonon collisions is considerable in the surface vicinity. Moreover, some osc illations in surface temperature occur in response to repetitive pulse frequency. It is less likely that the temperature profile follows the pulse profile which is due to the conduction losses and the motion of the slab.