Nanohardness and fracture toughness of combustion chemical vapor deposition deposited yittria stabilized zirconia-alumina films

Eutectic composition films, that were annealed for 2.5-10 h at 1500 °C, displayed coarsening of the second phase YSZ particles. Film hardness decreased by about half (∼22 to ∼11 GPa) after five or more hours of annealing, while fracture toughness reached a maximum of 3.33 MPa m0.5 after a 5 h anneal.