The plasma spraying coatings of Al2O3, 3%TiO2-Al2O3, 13%TiO2-Al2O3, TiO2 and partially stabilized ZrO2 films on aluminum alloys have been carried out. 13%TiO2-Al2O3 coating shows the best results in the tests of various bendings. The formation of main cracks are clearly detected by the comparison of the bending stress-strain curves of specimens coated with ceramics on tension side and those on compression side. The brittleness of the ceramics coatings is evaluated by the bending test of the specimens without undercoatings.
