초록
In this paper, the effect of the compressive residual stresses was obtained at the test conditions of the higher temperature than the ambient temperature. The examination was performed with the CT specimen result of the material(JISG SUP9) which is being commonly used for the marine engine parts and the ocean structures. As a result, the test conditions at the higher temperature were acquired considering the peak values of the compressive residual stresses of the specimens and the effect on the fatigue crack propagation speed da/dN in stage II and the threshold stress intensity factor range Δth in stage I. Also the material constant C and the fatigue crack propagation index m in the formula of Paris Law da/dN=C (ΔK)$^{m}$ were suggested to estimate the dependence on the test temperature.