Variations in acoustic emission characteristics across different deformation stages of various materials

Abstract

Integration of acoustic emission (AE) monitoring with traditional mechanical testing presents an attractive methodology for the prediction and assessment of material failure processes. While AE monitoring during mechanical testing has been extensively applied to study deformation and fracture in individual materials, conducting a comparative analysis across various monolithic materials using a single AE system provides valuable insights. This approach helps identify material-specific signal characteristics and behaviors that are essential for predicting failure in complex, multi-material structures. In this study, uniaxial testing with AE monitoring was conducted for evaluating failure behaviors of four different materials, namely low-carbon steel, aluminum alloy, acrylic and white Portland cement (WPC). The AE patterns obtained from tensile testing of ductile metallic materials, low‑carbon steel and aluminum alloy clearly indicated the regions of elastic, plastic and fracture by difference of peak amplitude intensity of AE signals. AE signals obtained from brittle materials, PMMA acrylic and WPC specimens showed fluctuated AE peak amplitude intensities throughout the linear deformation region until specimen fracture. The AE signals and their corresponding Fast Fourier Transform spectra provide data indicating failure of different materials, as well as failure behaviors, i.e., elastic, plastic and fracture, of ductile metallic materials.