Superficial modification of a Ti-6Al-4V alloy by laser peening

This research work was focused on the laser peening surface process in a metallic Ti-6Al-4V biomaterial. The Ti-6Al- 4V samples were surface treated at different laser conditions varying parameters such as pulse density and wave length. Laser peening induced effects were evaluated by synchrotron radiation X-ray diffraction (SR-XRD) to determine the residual stress state; scanning electron microscopy (SEM) to assess microstructural changes and thermoelectric testing (TEP) to sense the subtle material variations such as local texture, increased dislocation density, hardening and residual stresses degree. The TEP measurements demonstrate that the non-contact technique is very sensitive to the compressive residual stresses with increasing the severity of the laser treatment parameters, while the TEP contact results are closely related to grain size, cracks, anisotropy, and work hardening.