Elastic and inelastic properties of (Co$_{0.45}$Fe$_{0.45}$Zr$_{0.1}$)$_x$(Al$_2$O$_3$)$_{1-x}$ nanocomposites

The elastic (Young’s modulus) and inelastic (internal friction) properties of amorphous (Co$_{0.45}$Fe$_{0.45}$Zr$_{10}$)$_x$(Al$_2$O$_3$)$_{100-x}$ nanocomposites with various relative contents of the metallic and dielectric phases have been studied. In the region of low temperatures, the composites exhibit a peak of the internal friction (at $\sim$240 K), the intensity of which increases with the content of the metallic phase. For compositions above the percolation threshold, the temperature dependence of the internal friction exhibits exponential growth above 300$^\circ$C, which is related to the migration of vacancy-like defects in the amorphous structure of the metallic phase.