Effects of TiO2 on the mechanical properties of the Al2O3–TiO2 plasma sprayed coating

Plasma sprayed ceramic coatings are successfully used in many industrial applications, where high wear and corrosion resistance with thermal insulation are required. In this study, various types of Al2O3–TiO2 plasma sprayed coatings in different compositions (Al2O3–13 wt.% TiO2, Al2O3–40 wt.% TiO2 and Al2O3–50 wt.% TiO2) were prepared on an AISI 304L austenitic stainless steel substrate. The effects of TiO2 addition on the properties of the coating were investigated in terms of microhardness and fracture toughness values. The results obtained from experimental work were evaluated with standard characterisation techniques. The results indicated that an increase in TiO2 amount improves fracture toughness and lowers the microhardness values of the coatings.