回転曲げ2段多重応力変動装置の開発とそれを用いた二,三の実験結果 : (<小特集>強度設計・安全性評価小特集)

概要

論文の詳細を見る
In order to obtain fatigue strength data in long life range over 10^8 stress cycles under multiple two-step varying load conditions with high frequency of Hi/Lo block cycles, an automatic load changing device for uniform rotating bending fatigue testing machine was developed. With this device can be conducted the repeated Hi/Lo varying load fatigue tests with short interval of the higher stress level of about 100 cycles. It was confirmed, through experiments done by using JIS. S45C round bar specimens, that the level of performance of the newly developed load changing device was high. Furthermore, the discussion on the results from the viewpoint of the linear cummulative damage laws showed that, in some cases, the effect of understressing on fatigue lives appeared in two opposite manners, i.e., fatigue lives became considerably longer than estimated values or vice versa, especially when the number of understressing cycles was sufficiently large. To reveal such a inconsistent effect of understressing, and further, to clarify the fatigue behaviors in long life range up to 2×10^9 stress cycles, the authors intend to conduct a series of experiments systematically.
社団法人日本材料学会の論文
1990-01-15