【摘要】 目的:研究二次烧结工艺对纳米氧化锆陶瓷可加工性能和机械性能的影响。方法:在各个不同温度段对氧化锆陶瓷坯体进行烧结,通过硬度和断裂韧度测算烧结温度对烧成体可加工性能的影响。确定第1次烧结条件后,通过对不同温度下二次烧结的试件硬度、断裂韧度和三点抗弯强度的检测,筛选最佳第2次烧结条件,使坯体通过二次烧结能够达到较高的机械性能。结果:当烧结温度为900℃时,可加工指数最高,M=0.73±0.09,显著高于其它温度烧结的试件(P<0.05)。第2次烧结的温度为1 300℃时,试件的硬度、断裂韧度分别为(14.0±0.36)GPa和(5.4±0.38)MPa.m1/2;温度为1 325℃时,材料的三点抗弯强度最高,达到(932±63)MPa。结论:经900℃/1 325℃烧结的氧化锆陶瓷能够兼顾便于加工和良好的机械性能。更多还原

【Abstract】 Objective: To study the effects of the second-time sintering temperatures on the machinability and mechanical properties of zirconia dental ceramic.Methods: The best condition for the first-time sintering was chosen to get a better machinability of the blocks.By testing the different mechanical properties(such as Vicker’s hardness,fracture toughness and three-point bending strength) the best condition for the second-time sintering was decided to get better mechanical properties.Results: The best machinability of the blocks appeared at the temperature of 900 ℃: M = 0.73±0.09(P<0.05).When the second-time sintering temperature reached 1 300 ℃,the hardness and fracture toughness of the blocks were(14.0±0.36) GPa and(5.4±0.38) MPa·m1/2.When the second-time sintering temperature raised to 1 325 ℃,the blocks′ three-point bending strength reached the highest point:(932±63) MPa.Conclusion:The zirconia ceramic sintered twice at the temperature of 900 ℃/1 325 ℃ shows good machinability and mechanical properties.更多还原