Estimation of Corrosion Fatigue-Crack Growth through Frequency Shedding Method

摘要: Corrosion fatigue-crack growth characteristics are important for the design of marine and off-shore structures. Design critical components requires data on rate at very low frequencies order 10−2 to 10−3 Hz. Experiments pose practical difficulties enormous test duration. To address this, it is proposed estimate corrosion crack using a frequency shedding method where shed with advance an exponential law. Fatigue-crack tests have been conducted Ni–Mn–Cr steel constant ΔK range 18 MPa√m (lower Paris regime) under lab air conditions as well 3.5 % NaCl solution. Crack plotted function presents straight-line trend in log–log scale 1–0.1 Hz; however, there change when dropped further, which could be due domination mechanism. understand role closure, closure estimates were obtained periodic intervals length effective stress intensity graphs suggest acceleration reduced.