Surface effects in pulsed laser beam irradiated shape memory alloys

The goal of the work is to comparatively assess the effect of laser irradiation on the surface of shape memory alloys for several less common alloy families. The effect of pulsed laser impingement on the composition of NiTi shape memory alloys is analyzed for different compositions and manufacturing paths, with the aim to locally reduce the Ni content and/or to use the laser as a precise selective tool to generate structural reinforcements in a partially sintered shape memory alloy prepared by mechanical alloying. For a Ni-Ti-Hf alloy, the superficial layer formed as a result of the surface re-melting shows major Ni loss. Fe-Mn-Si-Cr shape memory alloys revealed major oxidations that are drastically affecting the properties as a result of interaction with the laser beam, while for the Co-Ni-Ga alloys only minor compositional changes have been detected.