Static models of acoustic emission in smooth and cracked specimens

This paper contains results of extensive acoustic emission studies on flawed and unflawed specimens of low carbon structural steels tested at different loading rates. With regard to the tensile unflawed tests a detailed discussion of the stress dependence of emission activity below yield is presented. This analysis indicates that count rate per unit volume is directly proportional to loading rate with the constant of proportionality generally dependent on the applied stress. Using this finding to the description of deformation around the crack tip an analytical relationship between acoustic emission characteristics and fracture mechanics parameters is proposed. At low stress intensity levels there is a promising agreement between theoretical predictions and experimental data.