Damping characteristics of Al matrix composite foams reinforced by in-situ grown carbon nanotubes

Abstract The damping properties of Al matrix composite foams reinforced by in-situ grown carbon nanotubes (CNTs) have been investigated. The results show that the damping capacity of the CNT/Al composite foams is visibly enhanced with the CNT addition. The loss factors of the composite foams are found not only increase with the increment of CNT content but also increase with the porosity raising. For the 3.0 wt%-CNT/Al composite foams, the loss factor keeps the level of ∼0.26 at 25–200 °C and further increases to 0.36 when the temperature is elevated to 390 °C, which is ∼2.71 and 1.77 times higher than that of the pure Al foam, respectively. The damping improvement of CNT/Al composite foams is mainly due to the high inherent damping of CNTs and the formation of large numbers of well-bonded CNT-Al interfaces.