Near surface secondary stresses affecting the mechanical behavior

摘要

Phenomenological input clearly adds to the understanding of near-surface secondary stresses (residuals) implications on the global trend of the mechanical behavior. The current study relies on critical experiments that intended to determine the role of secondary stresses on fracture and fatigue processes. Frequently, the ability to shed light on the aforementioned issues is hindered by various factors acting along the same direction. For example, phase-stability effects, strain hardening, crack-tip blunting or closure beside residual stresses introduce complexities in Fatigue Crack Propagation Rate (FCPR) perturbations under imposed-load interactions. Experimentally based cases that are related to fatigue-crack initiation and propagation, monotonic fracture toughness parameters variation due to residuals are described and evaluated. It becomes apparent that a local approach promises further insights into the significant role of near-surface stresses on the global mechanical behavior in various circumstances.