Rupture propagation in hysteresial materials: Stress at a notch

Abstract Measurements have been made of stress concentration at notches in sheets of rubber displaying marked mechanical hysteresis. The notches represent model cracks and it is shown that when made in pre-stretched sheets they simulate the case of a propagating crack. The results from these ‘dynamic’ experiments differ greatly from those made under static conditions and the difference is attributed to hysteresis. The results imply that the stress concentration at a propagating crack in a hysteresial material will be lower than in the absence of hysteresis and also lower than that at a stationary crack in the same material. A theory is proposed to account for the effects and quantitative agreement with experiment is obtained.