抄録
A new smart stress memory patch has been developed which measured maximum stress, number of fatigue cycles and stress amplitude simultaneously using Kaiser effect of AE and crack length. In this study, the characteristics of crack propagation in this smart patch was evaluated. Pure copper was used for this sensor because its good corrosion resistance, stable crack growth and detectability of AE near yield point. Fatigue test was performed under the constant stress amplitude to evaluate the crack growth behavior using the relationship between stress intensity factor range and crack growth rate. The obtained fatigue crack propagation behavior was affected by maximum stress and stress ratio. The modified stress intensity factor was proposed to correct the effect of maximum stress and stress ratio. The master curve of crack propagation characteristics which was not affected by maximum stress and stress ratio could be obtained using this modified stress intensity factor.
