Abstract
The present authors have studied the structures of oxide films produced on Ti surfaces by dry and wet oxidation. The following results were obtained by transmission and reflection electron diffraction. (1) The dry oxidation films produced on Ti surface in air at 400°C for 5 min consisted of only rutile type crystals. (2) The wet oxidation films formed on Ti in boiling concHNO3 for 4 hr and 24 hr were found to take double layer structures composed of outer anatase and inner rutile layers, and the rutile layer grew with the immersing time. (3) Ti quenched in water after heating in air at 500°C for 3 min was covered with oxide layers composed of rutile and anatase, while only rutile crystals were detected in the oxide films which were formed on Ti quenched in oil after heating in air under the same conditions. (4) The oxide films formed on Ti hydride surface by heating in air at 300°C consisted of only rutile crystals, while both rutile and anatase crystals were found in the oxide films produced on Ti hydride surface by heating in air at 350°, 400°, 450° and 500°C. (5) The diffraction pattern of meta titanic acid (TiO2·H2O) obtained by hydrolysis of TiCl4 was found to be the same pattern as anatase type TiO2 crystal.The above results suggest that anatase type oxide detected in wet oxidation films would be hydrated oxide of Ti resembling meta titanic acid.
Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
