Volume 2, Issue 6 (November 1974)
Comparison of Static and Dynamic Mechanical Properties of Some Epoxy-Matrix Composites
Static and dynamic elastic moduli in flexure were measured for a diglycidyl ether of bisphenol A cured with metaphenylenediamine and some particulate composites with this polymer as the matrix. If it is assumed that these materials have tensile moduli which are about 0.925 of their compressive moduli, as has been noted for another epoxy system, dynamic moduli determined at very low strain values by a free-free flexural resonance technique appear to be very nearly equal to the tensile moduli in static flexure. However, little correlation was observed between the dynamic mechanical properties and other static properties such as flexural strength. This is partially attributed to the difference in stress patterns in the static and dynamic tests.