全瓷冠疲劳强度可靠性及各随机参数的分析研究

目的：通过获取全瓷冠疲劳可靠性分析中各随机参数的概率分布,以期为构建应力-强度干涉模型及全瓷冠疲劳强度可靠度计算打下基础。方法：通过查阅文献获取日常咀嚼荷载谱、通过获取ShofuVintage材料的S-N曲线,经过曲线拟合得到其应力-寿命曲线方程,根据疲劳极限曲线与Hertzian接触理论,计算得出ShofuVintage瓷材料1,5,10,15,20年的疲劳极限强度95%可信区间。结果：ShofuVintage瓷的应力-寿命曲线方程为ln（load）=ln（684.056）-0.041lnN;ShofuVintage瓷材料1,5,10,15,20年的疲劳极限强度95%可信区间分别为46.941MPa～58.886MPa,45.021MPa～56.619MPa,44.191MPa～55.629MPa,43.726MPa～55.096MPa,43.443MPa～54.657MPa。结论：成功获取了全瓷冠疲劳强度可靠性分析中各随机参数,材料疲劳极限随时间呈下降趋势。

The analytic research on random parameters in the fatigue strength reliability analysis of all-ceramic crown

Objective：To acquire the random parameters in tbe fatigue strength reliability analysis of all-ceramic crown,and to lay a basis of constructing a stress-strength inference model of all-ceramic crown and calculating the fatigue strength reliability of the all-ceramic crown. Method： Based on the S-N curve of Shofu Vintage porcelain to get the formula of stress-life curve is In （load） =In （684.056） -0.041 ＊ InN through the curve fitting. Based on fatigue limit curve and Hertzian contact theory to get the 95 % confidence interval of fatigue limit strength of 1 year, 5 years, 10 years, 15 years,20 years. Result： The formula of stress-life curve is In （load） =In （684.056） -0.041 ＊ InN. The 95 % confidence interval of fatigue limit strength of 1 year, 5 years, 10 years, 15 years, 20 years are respectively 46.941 MPa-58.886 MPa,45.021 MPa- 56.619 MPa, 44.19t MPa-55.629 MPa, 43.726MPa-55.096 MPa, 43.443 MPa-54.657 MPa. Conclusion： To acquire four random parameters in the fatigue strength reliability analysis of all-ceramic crown. The fatigue limit of porcelain decreased with respect to the change of time.