Investigation of deformation and fracture by acoustic emission data, correlation of digital images, and strain measurements

To analyze the deformation of solid bodies, it was proposed to use simultaneously three in situ methods of data registration, including loading diagram (macroscale level), correlation of digital images (mesoscale level), and acoustic emission (microscale level). The complex for multiscale in situ investigation of deformation and fracture processes, the operating principle of which is based on interconnection of duration of the characteristic stages of change in the informative parameters and their ratios with the leading scale level, was implemented. By the example of stretching of the samples of aluminum alloy D16 with cut of different depth, the characteristic stages of change in the derivative of the load applied, AE activity, and intensity of shear deformation on the degree of deformation were revealed. It was shown that the characteristic stages marked on graphs of changes in all informative parameters on time agree well between each other and refer to elastic deformation, parabolic strengthening, and crack propagation.