Investigation of welding depth with overlapping laser pulses

Abstract
Laser processing has became a valuable alternative to classical techniques in a large variety of technical applications : cutting, drilling, welding, etc. The development of laser metal processing techniques need a deep understanding of the basic physical phenomena, like temperature distribution and its evolution in a target during laser metal interaction. The heat conduction equation have been solved using a numerical method and the results are compared with penetration weld data obtained on tantal and stainless steel targets irradiated by a Nd:YAG laser with variable pulse width. Depending by pulses parameters (duration, rate of repetition, peak power, pulse-shape) and pulses overlapping the depth of weld has been investigated.