Fatigue Properties of Welded Roller-Quenched and Tempered (RQ) Steels

Axial fatigue tests were performed on unwelded and welded roller-quenched and tempered carbon and alloy steels. The effects of stress ratio, weld geometry, base metal tensile strength, and weld-peening on the fatigue resistance of submerged-are transverse butt welds in 3/4-inch-thick (19.1 mm) plates were studied. The fatigue resistance of welded constructional steels with reinforcement intact was practically independent of tensile strength and stress ratio at lives greater than 200,000 cycles. Removal of reinforcement restored the pulsating tension fatigue strength to that of the unwelded material at lives greater than 400,000 cycles.