Advances in laser processing of metal matrix composites (MMCS)

The present work deals with the application of a High Power Diode Laser (HPDL) to improve the mechanical properties of Al₂O₃ particle-reinforced Aluminum Matrix Composites (AMCs). An experimental plan in which laser power and interaction time were individually varied was carried out to evaluate the influence of both process parameters on the surface performance of the AMCs. In this respect, the evolution of their surface morphology was assessed by contact-gauge profilometry. Further samples were, then, analyzed by FIMEC micro-indentation test, depth-sensing load controlled scratch and wear test. Experimental findings show that mechanical and tribological proprieties of the laser treated substrates can be considerably improved, although in an operating range of process parameters rather narrow. Finally, an analytical model was proposed to correlate the wear performance of the AMCs investigated to their morphological and mechanical properties.