The emission of Rayleigh waves from brittle fracture initiation, and the possible effect of the reflected waves on crack arrest

— The pop-in initiation and arrest behaviour in weldments of a structural steel, have been characterized with acoustic emission measurements. It was found that strong Rayleigh waves radiate from the crack tip in a preferred direction. Literature examinations and reanalysis of previous crack arrest test results, clearly indicate that the Rayleigh waves will be reflected back from edges on the crack surface and cause a crack closure effect upon arrival at the running crack tip. The phenomenon is tentatively called AUTOARREST (automatic arrest caused by release of stress waves from the crack itself).