High-Temperature Oxidation Behavior of Ti2AlC in Air
- 695 Downloads
The isothermal oxidation behavior of bulk Ti2AlC in air has been investigated in temperature range 1000–1300°C for exposure time up to 20 hr by TGA, XRD, and SEM/EDS. The results demonstrated that Ti2AlC had excellent oxidation resistance. The oxidation of Ti2AlC obeyed a cubic law with cubic rate constants, kc, increasing from 2.38×10-12 to 2.13×10-10 kg3/m6/sec as the temperature increased from 1000 to 1300°C. As revealed by X-ray diffraction (XRD) and SEM/EDS results, scales consisting of a continuous inner α-Al2O3 layer and a discontinuous outer TiO2 (rutile) layer formed on the Ti2AlC substrate. A possible mechanism for the selective oxidation of Al to form protective alumina is proposed in comparison with the oxidation of Ti–Al alloys. In addition, the scales had good adhesion to the Ti2AlC substrate during thermal cycling.
Unable to display preview. Download preview PDF.