In order to increase the bone bonding-ability and biocompatibility of zirconia-based implants, the surface roughness must be high. In this study, we tried to improve the surface roughness of the zirconia substrates by surface modification using two types of zirconia slurry and spin coating. We also investigated to the effect of repeated coating times on the surface roughness of coating layer. Coating layers fabricated by slurry and spin coating showed uniform thickness and dense microstructure. As increasing the repeated coating times, the thickness of coating layer gradually increased from 0.7 to 1.7 μm in case of small particles or from 0.9 to 2.0 μm in case of large particles. Slurry containing small particles (~ 40 nm) had low viscosity and good forming-ability of coating films, but the improvement of surface roughness by slurry coating was not high. Roughness enhancement on coated layer in zirconia slurry containing large particles (~100nm) was higher than that of small particles at the same processing condition. In this study, 4 times coating specimen showed maximum surface roughness of Ra 0.36 μm in 3Y-TZP powder containing large particles, or Ra 0.27 μm in that of small particles.

Keywords: Zirconia Slurry, Solid loading, Spin coating