The nitriding or the carburation of a titanium substrate assisted by a laser source has been extensively studied, but the laser induced oxidation phenomena have not been so much investigated. Taking account the problem complexity due to the large number of possible oxidation stages, we have elaborated and carefully characterized the oxidized layers. Physico-chemical analysis (Auger and XPS), phases identification (XRD θ-2θ and grazing), or morphological observation (SEM) have been performed. Elementary analyses using microprobe EDS and emission optical spectroscopy have been undertaken to finally precise the oxygen diffusion insertion. Explanations of the formation of the oxidized compounds are suggested in link with the Ti -O diagram. The thermal cycles undergone by the titanium substrate during the laser treatment have been also simulated to help clarifying the role of the cooling rate as well as the repetition rate on the presence of some metastable phases.
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