Macro-micro analysis of mechanical properties of Al0.6CoCrFeNi high-entropy alloy particle-reinforced Al-based composites

Abstract

In this study, Al0.6CoCrFeNi high-entropy alloy particle-reinforced 5052Al-based composites with good surface morphology and different diffusion layer thicknesses were successfully prepared using hot-press sintering and annealing, which were subsequently characterized by XRD, SEM, EBSD, micropillar compression, and nanoindentation. The EBSD tests indicate that the Al0.6CoCrFeNi high-entropy alloy has a dual-phase crystal structure with the presence of both FCC and BCC phases inside, and the internal grain size is significantly higher than that of the matrix. Subsequently, the mechanical property mapping images of the particle-diffusion layer-matrix region on the composite surface were obtained using the NanoBlitz 3D method in the nanoindentation experiments. And based on the particle and matrix mechanical property parameters obtained by nanoindentation experiments, they were fitted into different mathematical models to obtain the hardness and elastic modulus of the composite. As a result, the correlation was found to be linear, and the slope of the fitted straight line increased gradually with the prolongation of the annealing time. In conclusion, it is evident from the comparison of the results of mathematical model fitting of mechanical property parameters with the results of macroscopic mechanical property tests that the P. G. Klemens model exhibits an excellent fitting effect on the macro-microscopic mechanical properties of particle-reinforced aluminum matrix composites compared with other models such as the rule of mixtures.