High gradient directional solidification furnace

摘要

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). By varying the input of heat via the booster heater (40) and output of heat via the heat transfer plate (70), a desired thermal gradient profile (120) may be provided.