Elastic constants and delamination strength of a glass-fiber-reinforced polymer composite

Abstract

This work describes the results of experiments performed to determine a complete set of independent elastic constants and the effect of shock-induced shear strain on the delamination strength of a glass-fiber-reinforced plastic composite (GRP). The set of elastic constants are utilized to determine the delamination strength of the composite from the experimentally obtained stress-wave profiles in the composite. The principal results of this work may be summarized as follows: (i) the elastic wave velocity data indicate that the composite has tetragonal symmetry; (ii) the deformation of the composite under shock-wave compression normal to lay-up direction is elastic to 1–3 GPa; (iii) the composite needs to be pre-shock compressed to 0·07GPa in order to delaminate GRP under rarefaction induced tension; (iv) the delamination strength of the composite decreases with an increase in the shock-induced shear, i.e. whereas the delamination strength of the composite under zero induced shear strain is 0·06GPa, its magnitude decreases to 0·007GPa under shock-induced shear strain of 0·002.