Epoxy core with expandable microspheres

摘要

A method of fabricating a formed structure with expandable polymeric shell microspheres. A first plurality of polymeric shell microspheres are heated from an unexpanded state to an expanded state to form a plurality of expanded microspheres. The plurality of expanded microspheres are mixed with an epoxy resin and a second plurality of unexpanded polymeric shell microspheres. The mixture is formed in a shape to create a preform 20. The preform 20 is wrapped with fiber tape 22 to create a wrapped preform. The wrapped preform is placed in a mold. The mold is heated and the second plurality of unexpanded microspheres expand from an unexpanded state to an expanded state. The mold is cooled and the formed structure is removed from the mold.