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The use of titanium and its alloys is currently considered very attractive for dental implants, with the improvement of physical properties, corrosion resistance and biocompatibility of them. These properties are attributed to the formation of titanium dioxide (TiO2) as a protective layer. The aim of this work is to understand the influence of time on heat treatment of CP-Ti Grade II at 850 oC. Heat treatments were performed for 5, 15, 30, 60 and 120 minutes. The response of titanium to oxidation at same temperatures and various timings has been investigated, in terms of wear resistance, surface morphology and oxide layer substrate adhesion. A variety of experimental and analytical techniques including scanning electron microscopy (SEM) and tribological testing have been used to characterize the resultant thermal oxidized surfaces. The results showed that oxygen diffused Ti structure can produce compact layer (TiO2), which exhibited good adhesion with the substrate at 30 minutes and 120 minutes of heat treatment.

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This paper presents a concept of thermal barrier coating used to prevent exfoliation and increase the maximum working temperature of a turbine engine. The coating consist of a ZrO2/20%Y2O3 ceramic layer and a NiCrAlY adherent layer, deposited by atmospheric plasma spraying (APS), on a Ni super alloy sample usually used for the manufacturing of turbine blades. The sample was subjected to thermal treatment and after that analyzed. SEM images of the samples were taken, to analyze their behaviour to thermal treatment. . Reference sample (without thermal treatment) and samples subjected to 5, 10 and 15 hours heat treatment were investigated using X-ray diffraction in 25-130o 2θ interval.