摘要
The corrosion fatigue crack growth and near-threshold characteristics of a medium strength steel HT60 were investigated using compact tension specimens exposed to synthetic sea water. The da/dN-△AK_(eff) relation in air can give a conservative estimation of da/dN-△K relations in sea water. In the case of high R, however, crack growth acceleration at high △K regions appears to be cantrolled by the stress-assisted dissolution. The crack opening stress inlensity factor K_(op) detected by the back-face-strain method is the result of crack surface in contact with the corrosion products and therefore an overestimated value of K_(op) at the crack tip is given.
The corrosion fatigue crack growth and near-threshold characteristics of a medium strength steel HT60 were investigated using compact tension specimens exposed to synthetic sea water. The da/dN-△AK_(eff) relation in air can give a conservative estimation of da/dN-△K relations in sea water. In the case of high R, however, crack growth acceleration at high △K regions appears to be cantrolled by the stress-assisted dissolution. The crack opening stress inlensity factor K_(op) detected by the back-face-strain method is the result of crack surface in contact with the corrosion products and therefore an overestimated value of K_(op) at the crack tip is given.