THERMAL INTEGRATION IN LASER-PULSE HEATING - A KINETIC-THEORY APPROACH

In laser surface treatment, the metallurgical changes depend upon the heating and cooling rate of the process. However, laser pulse heating is popular due to the ease and low cost of its operation. Consequently , thermal integration of the heating process becomes important insofar as pulse heating of surfaces is concerned. The present study was carr ied out to examine the thermal integration process during the pulse la ser heating. An electron-kinetic-theory approach is introduced when mo delling the heat-transfer mechanism. To determine the effect of the la ser pulses on the thermal integration process, pulses having different power intensities, pulse lengths and repetition rates are taken into account. In the first case, a high intensity pulse followed by a serie s of pulses having the same pulse length and repetition rate, but diff erent intensities, is considered. In the second case, a high pulse int ensity followed by a series of pulses with the same intensity and puls e length, but different repetition rates, is considered. It is found t hat the thermal integration is possible for repetitive pulse heating a nd the second attempt introduced in the present study gives an improve d thermal integration process.