ELASTIC-CONSTANTS AND DELAMINATION STRENGTH OF A GLASS-FIBER-REINFORCED POLYMER COMPOSITE

This work describes the results of experiments performed to determine a complete set of independent elastic constants and the effect of shoc k-induced shear strain on the delamination strength of a glass-fiber-r einforced plastic composite (GRP). The set of elastic constants are ut ilized to determine the delamination strength of the composite from th e experimentally obtained stress-wave profiles in the composite. The p rincipal results of this work may be summarized as follows: (i) the el astic wave velocity data indicate that the composite has tetragonal sy mmetry; (ii) the deformation of the composite under shock-wave compres sion normal to lay-up direction is elastic to 1-3 GPa; (iii) the compo site needs to be preshock compressed to 0.07 GPa in order to delaminat e GRP under rarefaction induced tension; (iv) the delamination strengt h of the composite decreases with an increase in the shock-induced she ar, i.e. whereas the delamination strength of the composite under zero induced shear strain is 0.06 GPa, its magnitude decreases to 0.007 GP a under shock-induced shear strain of 0.002. Published by Elsevier Sci ence Ltd.