CAJ | 학술논문

目的：研究口腔临床修复中 WL 和 HT 氧化锆陶瓷的弯曲强度可靠性和循环载荷下亚临界裂纹扩展（SCG）情况。方法：采用 Weibull 分布分析由三点弯曲强度实验获得的2组样本（n ＝15）的弯曲强度数据和由循环疲劳实验获得的2组样本（n ＝15）的循环疲劳断裂次数数据；通过帕里斯定律（Pairs Law）分析试样在循环载荷下的亚临界裂纹扩展情况，SCG 行为通过疲劳裂纹扩展速率（da／dN）和最大应力强度因子（KImax ）的函数关系来表述。结果：WL 和 HT 的三点弯曲强度 Weibull 模数分别为10．64和12．04；应力腐蚀指数 n 分别为23．71和32．87；亚临界裂纹扩展（SCG）导致其失效的概率分别为90％和76．7％；发生亚临界裂纹扩展时的亚临界应力强度因子 KImax仅相当于其临界应力强度因子的49．6％和50．9％。结论：WL 和HT 在循环载荷下存都在亚临界裂纹扩展，HT 陶瓷的亚临界裂纹扩展的最低速率低于 WL 陶瓷（νHT ＜νWL ）。
목적：연구구강림상수복중 WL 화 HT 양화고도자적만곡강도가고성화순배재하하아림계렬문확전（SCG）정황。방법：채용 Weibull 분포분석유삼점만곡강도실험획득적2조양본（n ＝15）적만곡강도수거화유순배피로실험획득적2조양본（n ＝15）적순배피로단렬차수수거；통과파리사정률（Pairs Law）분석시양재순배재하하적아림계렬문확전정황，SCG 행위통과피로렬문확전속솔（da／dN）화최대응력강도인자（KImax ）적함수관계래표술。결과：WL 화 HT 적삼점만곡강도 Weibull 모수분별위10．64화12．04；응력부식지수 n 분별위23．71화32．87；아림계렬문확전（SCG）도치기실효적개솔분별위90％화76．7％；발생아림계렬문확전시적아림계응력강도인자 KImax부상당우기림계응력강도인자적49．6％화50．9％。결론：WL 화HT 재순배재하하존도재아림계렬문확전，HT 도자적아림계렬문확전적최저속솔저우 WL 도자（νHT ＜νWL ）。
Objective:To evaluate the reliability of flexural strength and subcritical crack growth(SCG)of WL and HT zirconia ce-ramics under cyclic loading.Methods:Bar-shaped speciments of WL(n =30)and HT(n =30)were fabricated and loaded in three-point bending and cyclically fatigued.The flexural strength and the number of cycles to fracture were obtained from three-point flexural test and cyclic fatigue test respectively.Data were examined using Weibull statistics.Pairs law was used to analysize the subcritical crack growth(SCG),the behavior of which was described in terms of crack velocity as a function of maximum stress intensity factor (KImax ).Results:The Weibull module(m)of WL and HT was 10.64 and 12.04,the stress corrosion cracking susceptive indexes(n) 23.71 and 32.87,the SCG 90% and 76.7%,the KImax 49.6% and 50.9% of its maximum stress intensity factor(KIC ),respectively. Conclusion:WL and HT produce pronounced SCG.The minimum fatigue crack growth rate of HT is lower than that of WL(νHT <νWL ).