牙科玻璃渗透氧化铝陶瓷弯曲强度Weibull分析和循环载荷下亚临界裂纹扩展研究  

Weibull Analysis of Flexural Strength and Subcritical Crack Growth under Cyclic Loading of Glass-infiltrated Alumina-based Dental Ceramics

作　　者：张志升 徐勇 肖云 苏剑生[2] 刘伟才[2] 陈萍 

机构地区：[1]厦门市口腔医院修复科,福建厦门361003 [2]上海同济大学口腔医学院 [3]福建省特种陶瓷重点实验室

出　　处：《口腔医学研究》2011年第3期204-206,共3页Journal of Oral Science Research

摘　　要：目的:研究牙科玻璃渗透氧化铝陶瓷(IA,In-Ceram Alumina)弯曲强度(σ)Weibull分析意义和循环载荷下亚临界裂纹扩展(SCG)情况。方法:分别采用三点弯曲强度测量方法(3p)和循环疲劳(F)测试方法测得15个条形IA样本的弯曲强度以及15个条形IA样本的循环疲劳断裂循环次数,数据采用Weibull方法分析;亚临界裂纹扩展(SCG)行为通过裂纹扩展速度和最大应力强度因子(KImax)的函数关系来描述。结果:IA的Weibull模数为7.9,特征强度(σ63.21)为438.3MPa。IA在循环载荷下发生亚临界裂纹扩展后导致材料断裂,在应力强度因子K1为临界应力因子KIC的55%时发生裂纹传播。结论:牙科玻璃渗透氧化铝陶瓷循环载荷下存在亚临界裂纹扩展;采用弯曲强度测试法并结合使用Weibull分析方法能加深对口腔陶瓷修复失败机制的理解。Objective：To evaluate the Weibull analysis of flexural strength（σ） and subcritical crack growth（SCG） under cyclic loading of glass-infiltrated alumina-based（IA,In-Ceram Alumina）.Methods：Bar-shaped specimens of IA（n=30） were fabricated and loaded in three-point bending（3p）and cyclic fatigued.The initial and the number of cycles to fracture were obtained from（3p）and F tests,respectively.Data were examined using Weibull analysis.The SCG behavior was described in terms of crack velocity as a function of maximum stress intensity factor（KImax）.Results：The Weibull moduli of IA was 7.9.63.21% fractural probabilities of IA was 438.3MPa.IA was prone to SCG,with crack propagation occurring at KI as low as 55% of its critical stress intensity factor（KIC）.Conclusion：Glass-infiltrated alumina-based dental ceramics cause pronounced SCG and Weibull analysis can be used as a design parameter of brittle ceramic for clinical practice,which will introduce a well-understanding of the tested values.

关 键 词：玻璃渗透氧化铝陶瓷 弯曲强度 循环疲劳 Weibul分析 亚临界裂纹扩展 

分 类 号：R783.1[医药卫生—口腔医学]