プログラム荷重による疲労強度に及ぼす応力順序の影響

概要

論文の詳細を見る
The annealed S35C carbon steel was tested under the four-step-in-stress bending program loading. The effect of the stress sequence on the fatigue lives was investigated with respect to the effects by the initial stress level and the magnitude of stress levels as a whole. The number of cycles in one program block was n_0=3600 cycles. the results show: (1) The effects of the initial stress level and the stress sequence on the fatigue lives can not be seen, because the value of n_0 in this experiment is very small compared with the total number of cycles to failure. (2) When the maximum stress σ_4 is large and all the stresses are overstresses, the fatigue lives nearly coincide with N_<th>'s which are calculated by the use of the linear damage law. When σ_4 becomes small, the fatigue life N_f also becomes smaller than N_<th>, and N_f reaches the smallest value at certain stress level. When the all stresses except σ_4 are understresses, the fatigue life N_f becomes equal to or larger than N_<th>.
社団法人日本材料学会の論文
1968-02-15