Effect of Surface Treatment on Friction and Wear Behavior of Dental Porcelain
表面处理工艺对长石质牙科陶瓷摩擦学特性的影响

Dental porcelain VitaVMK95 was subject to auto-glazing, surface ion exchanging, and polishing, respectively. The effect of various surface treatments on the friction and wear behavior of the dental porcelain was investigated on a Deltalab-Nene reciprocal friction and wear test rig. Thus the plane specimens made of the surface-treated dental porcelain were made to slide against a pure titanium ball counterpart under the lubrication of a synthetic saliva. The wear scars of the dental porcelain specimens were observed with a co-focus laser-scanning microscope, and the elemental composition thereof was determined on an energy dispersive spectrometer. Moreover, the surface roughness, surface hardness, and fracture toughness of the dental porcelain specimens subject to different surface treatments were measured so as to correlate the tribological properties and mechanical properties. It was found that the dental porcelain specimens subject to different surface treatments showed a little difference in the friction coefficients, i.e., the friction coefficients had a small difference at the early sliding-stage but assumed almost unchanged steady-state values. The dental porcelain after surface ion exchanging had better wear-resistance than the ones after auto glazing and polishing, and the later two showed almost the same wear-resistance. The friction and wear behaviors of the dental porcelain specimens subject to different surface treatments were nearly independent on the surface roughness and surface hardness, which was because the friction and wear behaviors of various dental porcelain specimens were closely related to their microstructures. In addition, Ti was detected on the worn surface of the dental porcelain specimen by EDS, which indicated that the counterpart Ti transferred onto the surface of the dental porcelain specimen during the lubricated sliding.