Oxidation behavior and oxide layers of Ti-50Al intermetallics by preoxidation in high-pressure oxygen
Journal
Oxidation of Metals
Journal Volume
54
Journal Issue
5-6
Pages
473-490
Date Issued
2000
Author(s)
Abstract
The oxidation resistance of Ti-5O Al intermetallics is improved by preoxidation for 1, 4, or 16 hours in high-pressure, pure oxygen (approximately 3.9 atm) at 900 °C. Specimens preoxidized for 1 hr exhibit better oxidation resistance than others. Prolonged preoxidation time can deteriorate the oxidation resistance and reduce the parabolic-linear transition time during subsequent cyclic oxidation in 800 °C air. The oxide-mound occurrence is an important factor for evaluating the effectiveness of the preoxidation treatment in oxygen. The formation mechanism of Z-phase (Ti5Al3O2) in the Al-depleted layer beneath the flat oxide scale and that beneath the oxide mound are also proposed in this study.
SDGs
Type
journal article