The plane-strain compression behaviour of glass and carbon/epoxy laminates

A test jig has been developed for the compression of flat plate laminates between parallel dies, making use of an ultra-stiff testing machine. Preliminary experiments have been carried out using this plane strain compression arrangement for a variety of laminates of differing fibre and matrix composition and with different specimen/die geometries. For all of the laminates investigated it was possible to determine a measure of elastic modulus, but strength could only be assessed for unidirectional layups owing to the yield/fracture strength of the steel dies themselves being exceeded for the woven composites. The results obtained compare well with those from the literature using more conventional compression tests.