MECHANICAL-PROPERTIES FOR CFRP DAMPING-MATERIAL LAMINATES

New materials that possess high damping capabilities and have high strength properties have been studied in carbon fiber reinforced plastics (CFRP). These materials are referred to in this article as CFRP/damping-material laminates. The CFRP/damping-material laminates investigated here are composed of a unidirectional carbon/epoxy prepreg sheet and a polyethylene-based damping material sheet used as an interleaf. Cantilever beam tests revealed the high damping properties of these laminates. Loss factor values for these composites are 5 to 50 times as large as that for conventional CFRP. These values could be predicted by using the analysis constrained layer damping treatment, except for two specimens. Also, the interleaving effect on tensile and compression strength are discussed here. Tensile test results for quasi-isotropic laminate based composites indicated that the damping material interleaf is effective for suppressing delamination and multiple splitting in the 0-degrees angle layer. The ultimate load increase of 3 to 15% was caused by this suppression effect. Compression test results suggest that the interleaf is not very effective for the compression strength increment.