An axial deformation technique for damping measurement is described. An aluminum specimen coated with transverse carbon/epoxy composite material was sinusoidally loaded in the axial direction. The phase difference between the strain measured in the coated region and that in the uncoated region was found from measurements on a pro grammable digital oscilloscope. The loss factor was found from the measured values of phase shift and axial stiffness. The loss factor is frequency-independent from 0.05 to 10 Hz and independent of axial strain from —1150 to 1250 μ∈ for this specimen.
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