Plasma Sprayed Alumina-Titania Based Coatings on Magnesium Substrates
In this study, pure alumina, titania and alumina 3% titania ceramics are deposited on magnesium substrate by plasma spray technique. The coatings were characterized by means of scanning electron microscopy (SEM), and x-ray diffraction (XRD). In the plasma spray coating, lamellar structures are formed as a result of the deformation of the melt semi-melt particles hitting the substrate and the solidification of the particles. As a result of the XRD analysis, Mg, AlMg, Ti5O6, Ti6O11, (Mg0,6Ti2,4)O5 and MgTi2O5 peaks were determined. The average hardness values of the samples coated with TiO2, Al2O3, Al2O3+TiO2 and TiSZ were measured as 921 HV0.1, 902 HV0.1, 914 HV0.1 and 1030 HV0.1 respectively. The hardness of the coatings is 16-18 times higher than the substrate.