A top cover formed from a metal matrix composite material for use on a data storage device is disclosed. The metal matrix composite material includes a porous matrix material combined with an inclusion material constrained within the pores of the porous matrix material. The porous matrix material is substantially aluminum while the inclusion material is a ceramic such as silicon hexaboride or aluminum boron carbide capable of wetting molten aluminum. The ceramic inclusion material is selected to have a specific modulus greater than the specific modulus of the porous metal matrix such that the entire volume of porous matrix material provides acoustical dampening during operation of the data storage device.