Extrusion Methods For Solid Freeform Fabrication

Abstract

It is becoming clear that current SFF methods are members of a potentially very large family. As with current forming methods, it is to be expected that particular materials and objects will lend themselves best to particular methods. Our group has been working for two years on extrusion methods of freeform fabrication where a reactive slurry is extruded into a pattern to form a series of layers that build up a three-dimensional object. A sketch of the apparatus is shown in figure 1. The slurry may cure chemically either as each layer forms or in a postcuring oven. As a member of the SFF family, this method offers great versatility in the range of materials that can be formed an in control ofthe material structure and composition within a part. This paper describes our efforts to extend the application of this method from ceramics to polymer composites, thermoplastics and silica-silica composites.