1991 年 40 巻 453 号 p. 712-717
Quantitative evaluation of applied stress by fractography is not always easy if fatigue striations are not seen on the fatigue fracture surface. The authors have often experienced such a problem in case of industrial machines which failed under low vibrational stress. In this report, the quantitative characterization of the fatigue crack surface created by low stress amplitude is attempted. A good correlation between the proposed surcace roughness parameter (S1) and the stress intensity factor range (ΔK) was obtained for low ΔK level. This technique is expected to be a supplemental method of quantitative stress evaluation of fractured component.