Nanocrystalline Mg-MAX composites: Mechanical behavior characterization via acoustic emission monitoring

This paper reports on the mechanical behavior characterization of a nanocrystalline Mg-matrix composite reinforced with Ti₂AlC by using the acoustic emission (AE) method. When Mg is reinforced with Ti₂AlC, the damping is greatly enhanced and, because the Mg grains are in the 50-100 nm range, the resulting composite has excellent mechanical properties. Monotonic and cyclic tensile, as well as low-cycle fatigue tests were carried out while simultaneously recording the AE activity. The latter was analyzed post-mortem and was additionally coupled with advanced pattern recognition techniques for classification and clustering of the AE signals. The results provide evidence related to the activation and evolution of a possibly novel deformation mechanism in this nanocomposite, and are further found to agree with previously reported theoretical and experimental findings.