Constant and Variable Amplitude Fatigue Behavior of Eight Steels
Abstract
Room temperature fatigue behavior was obtained for eight different steels, including cast, hot-rolled, quenched and tempered, and case-hardened steels, under both constant and variable amplitude load conditions. Constant amplitude fatigue crack growth behavior was obtained with compact-type specimens with load ratios R ≈ 0 and −1. Variable amplitude fatigue behavior was obtained from keyhole-notched compact-type specimens by using the Society of Automotive Engineers' transmission history and three modifications of this history including single tensile overloads. The keyhole specimen and the variable amplitude spectra were chosen to simulate room temperature real-life situations including both crack initiation and crack propagation. Fatigue behavior of the eight steels is compared.