Preparation Of HA-ZrO₂Composite Materials Based On MAM Freeform Fabracation

The research of Bio-ceramic materials gradually become a trend in the fieldof oral restoration because which could make up for shortcomings of metal materials,such as highly corrosive, impact of magnetic resonance imaging and poor color. Sofar there is no one Bio-ceramic materials having both excellent biological andmechanical properties, so its application is limited. Based on the concept offunctionally graded materials, it is expected to prepare biologicalceramic materialswith perfect performance, while the development of oral all-ceramic restorationscould be promoted. In this paper, hydroxyapatite ceramic （HA） with excellentbiological properties and zirconia ceramic （ZrO₂） with good mechanical properties areused as raw materials, and the “MAM （motor assisted microsyringe） freeformfabrication” is used to fabrication the composite materials of HA/ZrO₂.The factors which affect the stability of the ceramic slurry with single componentand composite components of HA and ZrO₂are researched at first in this paper. Theoptimal value of the dispersant content and the PH value are obtained by combiningthe results of experimental and analysis the mechanism of particle dispersion.Combined with the characteristics of technology used in this paper, determie the solidfraction of slurry and the content of other additives, finally get the best formula.The key process parameters are formulated and optimized by combiningtheoretical calculation and experimental in this paper, and the composite material isprepared successfully by adding buffer path with these optimized parameters.CaF2can improve the thermal stability of HA/ZrO₂composite materialseffectively, FHA/ZrO₂material with stable phase and dense micro-structure isobtained by pressless sintering at1400℃, the best content of CaF2is7.77wt%relative to the quality of HA ceramic. The composition ratio of ZrO₂affects thecombined form of the two materials and the properties after sintering. Finally, the ZrO₂-HZ4composite material is prepared by “MAM freeform fabrication” andpressless sintering.