Exploding pressure vessel test on zylon/epoxy composite

The efficiency of zylon/epoxy composites under radial load for the reinforcement of high-field magnet coils is studied using the exploding pressure vessel technique. Under the combined stresses in tangential and radial directions, the behaviour of zylon/epoxy composite is well described by the theory of orthotropic cylindrical shells when the pre-stress effects are considered. The ultimate tensile strength of the zylon/epoxy shell with a fibre-filling factor of 90% is found to be 4.8 GPa. The bursting pressure (maximal radial stress) is, for a given filling factor, a monotonically increasing function of the ratio of the shell thickness to inner radius. The beneficial effects of the pre-stress during winding on the reinforcement are discussed. (C) 2002 Elsevier Science Ltd. All rights reserved.