コースティックス法の精度に関する研究 : 試験片板厚および切欠き開口度の影響

概要

論文の詳細を見る
The caustic method is used to determine the stress intensity factor K_I. In the case of specimens with various thickness and different degrees of open notches, however, the caustic method gives an error in the evaluation of K_I. In this paper, the caustic method was studied for specimens with thicknesses from 2.0 to 7.7 mm and open notches from 0 to 90deg. for each thickness, providing 16 different combinations, under mode I loading. The results are summarized as follows. The transmitted caustic method is a useful technique to determine values of the stress intensity factor in these specimens. The conventional determination of K_I using the caustic method is valid for all of the above-mentioned combinations, when the initial curve radius γ_0 is larger than the minimum initial curve radius γ^<min>_0 obtained by this study. A linear relationship was found between γ^<min>_0 and the thicknesses for each notch opening. A method based on the distribution of three-dimensional stress field is proposed to expediently yield values of K_I using caustic method in the case of γ_0<γ^<min>_0.
一般社団法人日本機械学会の論文
1996-02-25