Acoustic emission wave propagation and source location in small, spherical composite test specimens : Whittaker, J.W.; Brosey, W.D.; Burenko, O.; Waldrop, D.A. Journal of acoustic emission, vol. 7, no. 1, pp. 31–40 (Jan./Mar. 1988)

Abstract

An elastic-plastic fracture mechanics (EPFM) procedure has been developed to analyse the crack initiation, stable growth and instability in the plane stress condition. The procedure is based on the Dugdale-Barenblatt strip yield model, but modified for the strain hardening and stable crack growth under monotonic loading. The crack opening angle (CTOA) is used as the crack growth criterion in the model. Analyses have been made for a relatively brittle 7075-T651 aluminium alloy, a ductile 2024-T351 aluminium alloy, and a relatively strong strain hardening 304 stainless steel, both for CT and CCT specimens. The same as for the small scale elastic-plastic finite element method which is based on the same CTOA criterion, the present procedure predicted the crack initiation, stable growth and instability in good agreement with experimental results for all the cases under investigation with maximum discrepancy around 10%. Together with the weight function theory and a new derived limit load solution, the developed model is shown to be very effective and efficient in analysing the residual strength of various configurations made of different sheet materials.