A critical review of experimental aspects in ratcheting fatigue: microstructure to specimen to component

In the past three decades ratcheting fatigue has attracted lots of research interest. Ratcheting can be defined as the directional progressive accumulation of plastic deformation of a material when it is subjected to a primary load along with a secondary cyclic load. The current article addresses the recent progresses made on the experimental front on the ratcheting behavior spanning from the specimen level to the component level and its correlation with microstructural evolution. The experimental aspects of ratcheting include the effect of stress levels, stress rate, temperature, planar anisotropy, previous loading history, and multiaxial loading paths. This work also discusses two test controlling modes engineering and true stress control ratcheting and their comparison, ratcheting-tensile, ratcheting-low cycle fatigue, ratcheting-ratcheting, ratcheting-creep interactions and ratcheting in component level. This summarized information clarifies why ratcheting is presently an important topic of engineering research.