ND-YAG LASER CLADDING - STUDY OF LOW-POWE R PROCESSING

This paper follows Lemoine's work [1]. It concerns the modelling of cl adding with Nd:YAG laser. Now we are interested in cladding with low l aser powers (typically P < 800 W). Experimental observations of the ev olution of the mass of the clads allows to show two power thresholds. The theoretical study relies on a calculation of fluence provided to t he substrate and on a model of heat transfer into the substrate. We su ppose that the first threshold is the required power for the melting o f the substrate. The second threshold is the power which allows to mel t directly the powder during its flight.