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1. Materials and methods: Annealed, polished pure titanium (TA 2 ) and Ti-6Al-4V alloy (TC 4 ) sheets were cut into pieces of 20 mm × 10 mm × 1 mm (18 pieces of TA 2 , 21 pieces of TC 4 ), sandblasted the surface of the sample, then ultrasonically washed in 75% ethanol and blown dry. The two titanium samples are divided into 6 groups of 3 samples each at 200 °C ~ 300 °C, 300 °C ~ 400 °C, 400 °C ~ 500 °C, 500 °C ~ 600 °C, 600 °C ~ 700 °C. Oxidation treatment was carried out in a porcelain oven (VACUMAT 100, Germany) at 600 °C to 750 °C for 10 min. The remaining three TC 4 samples were oxidized at 600 ° C to 750 ° C, and the surface oxide was removed with 500 mesh fine sandpaper, and the sample was subjected to X-ray diffraction inspection using a PW1700 automated powder diffractometer (Netherlands).
2. Results: After oxidation at 200 °C ~ 300 °C, the surface of TC4 has α-Ti peak and β-Ti peak, which is dominated by α-Ti peak. In addition, Ti 2 O 3 peak appears, indicating that there is oxide on the surface. form. After oxidation at 300 °C to 400 °C, a TiO peak appeared again, indicating that the titanium was further oxidized. After treatment at 400 °C to 500 °C, the α-Ti peak is further enhanced, and the β-Ti peak is not significantly changed; the titanium oxide peak is increased, and there are Ti 2 O 3 , TiO and brookite-type titanium oxide (TiO 2 B), indicating Oxidation is increased. In the range of 500 °C to 700 °C, the β-Ti peak increases with increasing temperature, and the α-Ti peak decreases. After oxidation at 500 ° C to 600 ° C, TiO, Ti 2 O 3 , TiO 2 , TiO 2 B and anatase titanium oxide (TiO 2 A) peaks appeared. After oxidation at 600 °C to 700 °C, a large amount of oxide is formed on the surface of titanium, and TiO, Ti 2 O 3 , Ti 3 O 5 , TiO 2 A, TiO 2 B and rutile-type titanium oxide (TiO 2 R) peaks appear. . After oxidation at 600 °C to 750 °C, the α-Ti peak is enhanced and the β-Ti peak is also obvious. The surface of TC 4 is formed by oxides such as TiO 2 , TiO 2 R and Ti 3 O 5 . After oxidation at 600 °C to 750 °C, the surface of the highly polished TC 4 and α-Ti peaks were increased with fine sandpaper, but TiO, TiO 2 and Ti 3 O 5 peaks were still observed.
TA 2 is oxidized at 200 ° C to 300 ° C to form mainly α-Ti peaks and a very low TiO 2 R peak. In the range of 300 °C to 750 °C, the α-Ti peak gradually increases with the increase of oxidation temperature, and the number of peaks increases. The peaks of TiO 2 A, TiO 2 R and Ti 2 O 3 gradually appear. The sample exhibited a light blue color after the oxidation of TA 2 at 750 °C.
3. Discussion: 1 There are more than 10 kinds of oxides of titanium. Under the condition of dental porcelain heat treatment, the increase of temperature can cause the increase of the amount of oxide on the surface of titanium, but whether it will cause the change of oxidized substances has not been reported [1, 2]. Our study found that when TA2 is oxidized for a short time in the range of 200 °C to 650 °C, in addition to its inherent α-Ti peak, peaks such as TiO 2 , Ti 2 O 3 and TiO 2 R appear. When TC 4 is oxidized, the peak change is remarkable, and in addition to the inherent α-Ti and β-Ti peaks, there are also TiO, Ti 2 O 3 , TiO 2 B, TiO 2 A, TiO 2 , Ti 3 O 5 peaks and the like. It shows that as the oxidation temperature increases, the amount of oxides formed on the surface of titanium increases not only, but also the type and structure type. 2 This study found that the amount, type and structure of oxides formed on the surface of titanium oxides oxidized under different temperature conditions. Oxidation at a temperature below 750 ° C for a short time, the oxide on the surface of the titanium material is mainly TiO 2 , in addition to Ti 2 O 3 , Ti 3 O 5 , TiO. TiO 4 can still detect TiO after grinding off the surface oxide film, indicating that the TiO is formed at a deeper position. Ti 2 O 3 and TiO may be sequentially present under the surface layer TiO 2 , and the ratio of the oxygen atom to the titanium atom content in the three oxides is 2:1, 3:2, and 1:1, respectively, that is, from the surface layer to the deep layer oxygen content. Gradually reduce [1-3]. We conducted a preliminary qualitative analysis of the surface oxide of titanium oxide oxidized from 200 °C to 750 °C, and basically grasped the formation of oxide on the surface of titanium in this temperature section. However, it is necessary to further study the mechanism of the composition and structure of the titanium oxide film in the combination of titanium and porcelain.
TA 2 and TC 4 titanium and titanium alloy surface of the sample porcelain gold surface is generally carried out [1-3] below 800 deg.] C, the range of detection 200 ℃ ~ 750 ℃ different temperature oxidation zone generated oxide type and structure, It can be understood that the oxidation of titanium surface at the clinical porcelain temperature helps to understand the mechanism of the combination of titanium and porcelain.