Fatigue crack growth rate behavior of tank car steel TC-128B

The fatigue crack growth behavior of TC-128B steel was examined in detail. Two different lots of TC-128B material, each in accordance with chemical and mechanical property guidelines, were tested and found to yield consistent FCG properties. Furthermore, the effects of R-ratio and specimen orientation both yield an overall two times factor on FCG rate for ΔK in the Paris regime. As the FCG threshold was approached, the effects of R-ratio and orientation generally increased. Finally, a favorable comparison was made between the TC-128B FCG data measured and several data representations from the literature.