ABSTRACT
Objective: To explore the preparation methods of nanomete r powder of ZrO 2 for dental application. Methods:Zirconia gel wa s dehydrated by heterogeneous azeotropic distillation process and n-butanol was used as azeotropic solvent. The properties of ultrafine powder obtained via dec ompression (process b), atmosphere pressure (process c) and direct ethanol-wash ing (process a) were studied. Results: After drying and calcini ng the gel, the ultrafine powder obtained from process a,b and c was about 25 n m,22 nm and 17 nm respectively. 3Y-TZP ceramic prepared with the three kinds of nanometer powder had bending strength of 660 MPa,710 MPa and 640 MPa; fracture toughness of 4.34 MPa?m 1/2 ,4.77 MPa?m 1/2 and 4.24 MPa?m 1/2 , respectively. Conclusion: By the heterogeneous azeotropic dis tillation process, zirconia ultrafine powder without hard agglomeration (d BE T=17 nm) can be obtained.