Charpy V-Notch Impact Behaviour of Structural Steels Subjected to Specific Manufacturing Conditions

AbstractThe influence on the Charpy V-notch impact behaviour in the transition region is investigated taking into consideration the residual stresses, work hardening and the surface topology at the notch root caused by manufacturing. Three materials were made available for the investigation, an unalloyed structural steel in the normalised and in the partially austenitised microstructural state, a water quenched hardened and tempered high strength, fine grained structural steel, and a heat treated steel. Initially, the effects of the major geometric parameters are identified with constant manufacturing conditions at the notch root (part I). As shown in the present contribution, the required almost constant notch root manufacturing conditions are obtained by means of a defined notch grinding process. Following notch machining of two steels, a stress relieving heat treatment was carried out. This heat treatment relieves virtually all the macroscopic residual stresses and the work hardening in the surface lay...