Abstract: A high gradient directional solidification furnace is disclosed which includes eight thermal zones throughout the length of the furnace. In the hot end of the furnace, furnace elements (25, 26, and 40) provide desired temperatures. These elements include Nichrome wire (28) received in a grooved tube (30) which is encapsulated by an outer alumina core (32). A booster heater (40) is provided in the hot end of the furnace which includes toroidal tungsten/rhenium wire (42) which has a capacity to put heat quickly into the furnace. An adiabatic zone is provided by insulation barrier (62) to separate the hot end of the furnace from a cold end. The cold end of the furnace is defined by heating elements (80 and 90). A heat transfer plate (70) provides a means by which heat may be extracted from the furnace and conducted away through liquid cooled jackets (72).

Abstract: A multi-purpose furnace for space vehicles used for material processing experiments in an outer space environment. The furnace contains three separate cavities designed to process samples of the widest possible range of materials and thermal requirements. Each cavity contains three heating elements capable of independent function under the direction of an automatic and programmable control system. A heat removable mechanism is also provided for each cavity which operates in conjunction with the control system for establishing an isothermally heated cavity or a wide range of thermal gradients and cool down rates. A monitoring system compatible with the rocket telemetry provides furnace performance and sample growth rate data throughout the processing cycle.