Damping behavior of titanium oxide reinforced ZA-27 alloy metal matrix composites

ZA-27 based metal matrix composites (MMCs) have been prepared with 1, 2, 3, and 4% of reinforcement by compocasting method. Sample specimens of dimensions 70mm � 10mm � 2mm were machined from the prepared ingots. The damping behavior and dynamic young's modulus of the base alloy and the particulate reinforced composites was studied over a temperature range of 30�C to 300�C by using a dynamic mechanical analyzer. The damping capacity of the materials was observed to increase with the increase in temperature whereas the dynamic modulus was found to decrease with the increase in temperature. The damping capacity at lower temperature may be attributed to coefficient of thermal expansion (CTE) mismatch induced dislocations and intrinsic damping of the matrix alloy whereas damping capacity at higher temperature may be attributed to matrix/reinforcement interface and thermoelastic damping.