Isotropic residual stresses in thermosetting resins: a new instrument for direct measurement

摘要

The development of isotropic residual stresses is important in thermoset cure. These stresses are conventionally determined by curing the material in a cylindrical tube having a large length-to-diameter ratio. Despite its popularity, questions arise whether the stresses are isotropic or not in this method. To surmount this ambiguity, we propose a new method of measuring the build-up of isotropic residual stresses by confining the thermoset resin in a spherical geometry, thereby maintaining a truly hydrostatic deformation on the material. This paper describes the method and presents preliminary results on a model epoxy resin.