DYNAMIC CORE MOVEMENTS DURING LIQUID MOLDING OF SANDWICH STRUCTURES

The paper describes an investigation of the processing of sandwich str uctures by resin transfer moulding. One of the major difficulties in p roducing sandwich elements in this way is displacement and deformation of foam cores during impregnation. Under extreme circumstances this m ay result in thickness variations, variable properties and voidage in the skins. Core shifting was studied using an incompressible core with in a glass fibre preform and the effects of process variables on core movement were isolated in a series of mouldings. The results demonstra te the significant effects of fluid pressure, fibre volume fraction an d mould temperature on the quality of sandwich laminates. (C) 1998 Els evier Science Limited. All rights reserved.