A study of oxide layer growth on the surface of aluminium alloys with Ti, Zr, Hf during heating in air

Abstract The growth of surface oxide films on binary aluminium alloys with transition metal (TM) Ti, Zr and Hf additives at temperatures 600 and 620° С in air was studied using the single-wave ellipsometry method (wavelength 0.6328 µm). It was shown that the annealing temperature affects the growth rate and extinction coefficient of surface oxide films for alloys having ∼5 at.% and ∼18 at.% TM in aluminium. Alloys with hafnium demonstrated the most active growth of oxide films during heating. A considerable increase in the extinction coefficients of oxide films was observed during oxidation of Al ∼18 at.% TM alloys. The optical properties of alloys (substrates) were found to correlate with their chemical composition. The aluminium alloys with 6 and 18.5 at.% Ti retain their resistance to thermal oxidation in air at the indicated temperatures.