Abstract
Porcelain veneered on pure titanium with an intermediate plasma-sprayed ZrO2 bond coat layer was investigated in this study. The pure porcelain coating veneered on Ti was used as a control. The specimens were subjected to four-point bending test to measure the bonding strength. The fractograph, microstructure, surface roughness, and phase of plasma-sprayed ZrO2 bond coat were examined. The phase constituents at the location of adhesive failure of the fractured specimens were investigated by thin-film X-ray diffractometry. Experimental results reveal that the bonding strength of the coating with the intermediate layer was increased by 55.7% that was accompanied by a significant decrease of the area of adhesive failure in the fracture. The ZrO2 provided a higher surface roughness to enhance the mechanical bond at the interface of porcelain/ZrO2, meanwhile it acted as a sufficient oxygen diffusion barrier at 800°C to prevent the oxidation of Ti at the interface of ZrO2/Ti.