Pulsed laser sintering of metallic powders

We have investigated the interaction of near infrared pulsed laser radiation with metallic powders both theoretically and experimentally at 1.064 mum with a pulsed Nd:YAG laser. The lower average power requirement (below 100 watts) in the case of pulsed interaction, predicted by calculations, has been confirmed. Temperature measurements show that a lower average temperature occurs whereas consolidation takes place at much lower average power compared to continuous wave sintering. The sintered material has been analysed and the results are compared to the calculation predictions: material analysis has shown that only a narrow surface layer of the individual powder particles has been affected by the interaction. Therefore, significant material modifications only take place in the mentioned surface layer of the single grains whereas the main part of the material remains unchanged. Furthermore. surface finishing of the work piece by means of a pulsed Nd:Glass laser have been performed, which leads to a bulk-like density at the surface. (C) 2003 Elsevier B.V. All rights reserved.