Al 合金A2024-T3のフレッティング疲労き裂進展挙動

概要

論文の詳細を見る
The crack propagation behavior in fretting-fatigue of A2024-T3 strip typed specimens was investigated under the repeated stress of 60 Mpa with three different stress ratio, namely R=0.33, 0, and -0.33, and the contact pressure of 50 MPa. The crack length a, the effective stress intensity factor range ΔK_<eff> proposed by J. Schijve, and the maximum stress intensity factor K_<max> were plotted as a function of crack propagation rate da/dN. It was seen that the crack propagation behavior in fretting-fatigue was affected by the stress ratio, and was able to be divided into two stages. In `S_I-stage' where the crack length is up to about 0.5 mm, the da/dN in fretting-fatigue was very high compared with that in unfretting-fatigue, but with crack growth the da/dN in freting-fatigue decreased markedly in the order of decreasing R. In `S_II-stage' the da/dN in fretting-fatigue increased with crack growth, and was higher than that in unfretting-fatigue for R=0.33, lower for R=-0.33, and almost the same for R=0. This behavior was interpreted by the reduction of ftetting effect with crack growth and by the crack surface contact due to slantwise crack characterized in fretting-fatigue and shear lips characterized in A2024-T3.
社団法人日本材料学会の論文
1985-09-15