Effect of Ti and Mg on the damping behavior of in situ aluminum composites

Damping capacity of in situ TiB2 particulate reinforced aluminum composites with Ti and Mg excess were investigated. The composites were fabricated with an exothermic reaction process via K2TiF4 and KBF4 salts. The damping behavior of materials over a temperature range of 30-300 degrees C was investigated by using a dynamic mechanical thermal analyzer. Experimental findings indicate that the damping capacity of composites with Ti, Mg excess, respectively is lower than that of Al/5 wt.% composite when temperature is below 180 degrees C and is higher than of Al/5 wt.% composite above 180 degrees C. The main effects of these elements are the formation of thin layers on TiB2 particulates, which resulted in the change of damping capacity. (C) 2005 Elsevier B.V. All rights reserved.