Internal friction peak and damping mechanism in high damping 6061Al/SiCp/Gr hybrid metal matrix composite

The damping properties of the 6061Al/SiCp/Gr hybrid MMC, which was fabricated by spray atomization and deposition, were studied. The results show that the internal friction spectra of the samples exhibit internal friction peak versus temperature at about 150 deg. C. Furthermore, the peak temperature increases with increasing frequencies, and the activation energy of the internal friction peak was calculated being 1.17 eV according to Arrhenius equation. Through a series of analyses, it is described that the internal friction peak is of relaxation model and its mechanism is of the dislocation-induced damping which results from the dislocation movement dragging the defect under the double action of heat and stress