牙科可切削氧化锆/磷酸镧复相陶瓷的初步研究

A pilot study on the dental machinable zirconia/La-monazite diphase ceramic

目的:探索牙科可切削氧化锆/磷酸镧复相陶瓷制备烧结特性。方法:按磷酸镧%(体积百分数):15%、18%、20%加入3mol钇稳定的氧化锆中,分别采用干压成型(12Mpa),冷等静压成型(200Mpa),在空气气氛中烧结,采用1560℃、1580℃、1600℃烧结温度,制得不同烧结温度下陶瓷样品,测试其各项性能。结果:氧化锆/磷酸镧复相陶瓷制备过程中最佳烧结温度在1580℃。磷酸镧含量可以增加氧化锆/磷酸镧复相陶瓷可切削性能并降低其机械性能。18%磷酸镧含量氧化锆/磷酸镧复相陶瓷具有较佳的综合力学性能。结论:采用冷等静压(200MPa)成型,空气中常压在1580℃烧结,可以得到致密的复合陶瓷。

Objectives： The aim of this experiment is to investigate the sintering and mechanical properties of the machinable zircunia/La-monazite diphase ceramic. Methods： La-monazite was added to tetragonal zirconia polycrystals stabilized with 3 tool-% yttria （TZP） at different volume percentage： 15%, 18% and 20%. The green bodies of three groups were compacted by cold isostatic pressing of 200MPa, and sintering under hydric and air atmosphere at different temperatures： 1560℃ , 1580℃ , 1600℃. The volume density, porous rate , three-point bend strength and differential thermal analysis （DTA） of the sintered bodies were measured. Results： The favourable sintering temperature of zirconia/ La-monazite diphase ceramic was 1580 ~C .With the concentration of La-monazite increased, the machinability of ceramic composite is better but the mechanical properties declined. Zirconia/La-monazite diphase ceramic with 18% La-monazite had the best mechanical property. Conclusions： Zirconia/La-monazite diphase ceramic can be sintered at 1580℃ to reach its idea density under cold isostatic pressing （200MPa）.