目的:探讨喷砂对氧化锆陶瓷材料三点弯曲强度和疲劳性能的影响.方法:按照随机数字表,将60个氧化锆陶瓷试样随机分成喷砂组和对照组,每组30个试样.喷砂组表面抛光后再进行喷砂处理,对照组表面进行抛光.对喷砂组和对照组进行三点弯曲强度测试,使用Weibull函数分析喷砂对HT锆瓷弯曲强度可靠性的影响,并采用成组t检验分析三点弯曲强度测试结果.对喷砂组和对照组进行疲劳实验,试样在循环载荷作用下的裂纹扩展情况用裂纹扩展速率曲线描述.结果:喷砂组和对照组的m-ZrO2相对含量分别为11.10％和6.24％.喷砂组和对照组三点弯曲强度测试结果分别为(1 228.36±137.33)MPa和(1 200.50士114.74)MPa,差异有统计学意义(P＜0.05);Weibull模数分别为13.52、12.03;应力腐蚀指数分别为35.80、32.87;发生裂纹扩展时的应力强度因子△K仅相当于其断裂韧性的51.90％和50.90％.结论:经过本研究所述方法喷砂处理后的HT锆瓷的三点弯曲强度升高,抵抗裂纹扩展的能力增强.%Objective:To evaluate the effect of sandblasting on the flexural strength and fatigue property under cyclic loading of the dental zirconia ceramics.Methods:After polished,sixty bar-shaped specimens of HT were assigned to two groups (n=30) according to the random number table,one of which was sandblasted by alumina particles,the other was polished.The flexural strength of experimental group and control group was obtained from three-point flexural test,then examined by Weibull statistics and analyzed by the group t-test.The number of cycles to fracture was obtained from cyclic fatigue test.The fatigue crack growth rate curve based on Pairs law was used to describe the crack propagation.Results:The phase content of m-ZrO2 experimental group and control group were 11.1％ and 6.24％.The flexural strength of experimental group and control group were 1 228.36+137.33 MPa and 1 200.55±114.74 MPa (P＜0.05).The Weibull module of the two groups was 13.52 and 12.03.The stress corrosion cracking susceptive indexes were 35.80 and 32.87.The crack propagation occurred at the critical stress-intensity factor was as low as 51.9％ and 50.9％ of its fracture toughness.Conclusion:After dealing with the method described in this article,both the flexural strength and the crack growth resistance of the HT are increased.
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