Damping behaviour of cyclically deformed 304 stainless steel

Abstract

Metallic materials are used in many applications because of their economy, strength and endurance limit. Fatigue damage is major contributor to failure or fracture in engineering materials.Energy dissipation, termed damping, occurs in engineering metals as a function of the cyclic loading hi story. Damping behaviour of materials has been estimated using many different experimental techniques, and parameters, i.e., the loss factor versus strain amplitude and frequency range. In order to measure energy dissipation, a damping monitoring method, which estimates the damping factor by vibration excitation, is used in this study.Under a constant cyclic load for high cycle fatigue, the effects of the number of fatigue cycles on damping are studied in 304 stainless steel. An empirical equation has been developed for constant energy increase per cycle up to fatigue crack initiation. Experimental and analytical results are compared. Besides small differences depending on some factors both values are in agreement.