Fatigue Crack Arrest Problem of Thick-Walled Cylinders under Thermal Stress : (2nd Report, Comparison of Cylinder with Single Edge Cracked Strip)

摘要

There is a rule of thumb'for thick walled cylinders, that is'circumferential fatigue cracks under thermal stress will be arrested at 1/3～1/2 of the wall thickness.'In this study, the reason for this will be clarified and a practical method for estimating arrest point will be proposed. In this paper, the characteristics obtained for a single edge cracked strip, which were reported in our previous paper are compared with those of cylinders with inner surface circumferential crack. From FEM results, it was concluded that cylinders show similar characteristics to those of single edge cracked strips from the standpoint of crack growth rate (including tendency of arrest) under cyclic thermal stress. In addition, thick cylinders always showed a tendency of crack arrest, assuming Paris'Law.