| 摘要 |
A process for fabricating pre-sintered zirconia blanks that are then computer machined and sintered to form dental appliances having highly advantageous features. The principal steps of a preferred embodiment of that process comprise a) preparing a ceramic slurry of binderless zirconia powder; b) subjecting the slurry to attrition milling down to about a 5-29 nm crystallite size; c) preparing a vacuum assisted and pressure assisted slip casting mold and pouring the milled slurry into the slip-casting mold; d) after casting, excess slurry is poured from the mold and a consolidated zirconia blank is removed; e) drying the blank and pre-sintering it to form solid blanks ready for CAD/CAM machining and sintering to net shape. The attrition is run with ball bearings that are of the sample material to prevent contamination. It also is run, up to 24 hours, to break down the crystallites to overcome the high density of zirconia. |
