A nanolaminate consisting of alternate layers of aluminium oxide (Al2O3) (5 nm) and zirconium oxide (ZrO2) (20 nm) was deposited at an optimized oxygen partial pressure of 3×10-2 mbar by pulsed laser deposition. The nanolaminate film was analysed using high temperature X-ray diffraction (HTXRD) to study phase transition and thermal expansion behaviour. The surface morphology was investigated using field emission scanning electron microscopy (FE-SEM). High temperature X-ray diffraction indicated the crystallization temperature of tetragonal zirconia in the Al2O3/ZrO2 multilayer -film was 873 K. The mean linear thermal expansion coefficient of tetragonal ZrO2 was 4.7×10-6 K-1 along a axis, while it was 13.68×10-6 K-1 along c axis in the temperature range 873-1373 K. The alumina was in amorphous nature. The FESEM studies showed the formation of uniform crystallites of zirconia with dense surface.

Keywords: Thin films, Ceramic, Composites, Multilayers, Alumina and zirconia, Thermal expansion