Short Term Oxidation of a Ti-46Al-8Nb Alloy at 700°C in Air
Thermogravimetry was used to study the oxidation behaviour of a lamellar Ti46Al8Nb alloy during holding at 700°C in synthetic air. A parabolic plot of the oxidation kinetics shows three different regimes over the total duration (50 h) of the tests corresponding to decreasing values of the parabolic rate constant. The oxide scale was characterized by glancing-angle X-Ray diffraction and transmission electron microscopy. The scale was found to be bi-layered with an outer part that consists of amorphous aluminium rich oxide whilst the inner layer is made of very small cristalites of titania distributed in the same amorphous oxide.
Luís Guerra ROSA and Fernanda MARGARIDO
P. E. T. Ngnekou et al., "Short Term Oxidation of a Ti-46Al-8Nb Alloy at 700°C in Air", Materials Science Forum, Vols. 636-637, pp. 485-490, 2010