SURFACE MODIFICATION AND TRIBOLOGICAL BEHAVIOR OF TITANIUM AND TITANIUM-ALLOYS AFTER YAG-LASER TREATMENTS

Commercially pure Ti and Ti alloys substrates have been treated using a YAG-Nd laser radiation (1.06 mu m). A large range of laser parameter s have been tested resulting in very different coloured layers. X-rays diffraction and Raman spectroscopy have been performed in order to ch aracterize the composition and crystalline structure of the coatings. Their roughness and thickness were also measured. Their tribological p roperties have been evaluated under fretting conditions against a 52 1 00 steel cylinder and compared with the fretting behaviour of uncoated samples. The evolution of composition and structure of the coating du ring friction has been studied. (C) 1998 Elsevier Science S.A.