Continuous filaments and eutectic composite materials have been treated as homogeneous and orthotropic and transversely isotropic elastic materials, respectively, in stress analysis problems. Based on these assump tions the elastic moduli of boron-epoxy and Al-Al3Ni eutectic composite materials are measured using pulse-echo techniques. The shear wave measurements show that the elastic anisotropy assumed for each material is only an approximation. The measurements are also influenced by defects in the fiber arrangement and, m the eutectic composite, by the presence of a solidification substructure.
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