Increasing the damping capacity of sheet materials with the aid of laminar coatings

The use of a rigid repressing layer (metal foil) causes an abrupt increase in the level of damping capacity of sheet specimens with coatings of Vibroisol and mastic VPM-2 GISI. The oscillation decrement is 12 times that of specimens with coatings without a repressing layer and 38 times that of uncoated specimens.

In specimens with coatings of Vibroisol and foil the oscillation decrement increases linearly with increasing thickness of the repressing layer.

In most of the investigated specimens with two-layer coating the level of oscillation decrement changes when the continuous coating is divided lengthwise, and this makes it possible to establish the optimum length of coating sections.

With equal geometric parameters and deformation amplitudes, the oscillation decrement of specimens with two-layer coatings containing mastic VPM-2 GISI was about twice as great as the oscillation decrement in specimens coated with Vibroisol and foil.