Graphite Machining Inc. (GMI) of Topton, Pa., and Solar Manufacturing of Souderton, Pa., have been cooperating for the past year on the development and testing of a new graphite board material and its application for vacuum furnace hot zones. The material has undergone extensive thermal and vacuum testing against GMI’s existing insulating materials. GMI intends to market the graphite board under the name of HEATGUARD insulation, while Solar Manufacturing will incorporate the material into its vacuum furnace hot zones under the trade name HEFVAC (high-efficiency vacuum).