Study On Surface Modification And Properties Of 3Y-TZP Ceramic Nano-Powders

Nano-powders have small particle size, large surface area and high activity. They are often heavily agglomerated during sintering, resulting in unfavorable influence on their properties. In order to solve this problem and obtain ceramics with excellent properties, powder surface modification was adopted in this paper.Tetragonal Zirconia Polycrystals (TZP) stabilized with 3mol% Y₂O₃ (3Y-TZP) ceramic powders, with an average grain size of 8.9nm, were prepared by precipitation-gel method. Carbon-coated 3Y-TZP powders with better crystalline structure and different carbon content (0⁷.0wt%) were obtained by CVD method.Sintering behaviors and microstructure of carbon-coated 3Y-TZP sintered at normally continuous sintering and two-stage sintering were investigated. Meanwhile effect of carbon content on 3Y-TZP with tiny grain and high relative density was investigated. Results show that compared with carbon-uncoated 3Y-TZP, 3Y-TZP with a little amount of carbon sintered at two-stage sintering by firing the sample at 1250℃ for 5 min and then rapidly cooling down to 1150℃ for 6h could give denser...