GEAR TO MELT AND CRYSTALLIZE MATERIALS Russian patent published in 2002 - IPC

FIELD: vacuum heat treatment of materials. SUBSTANCE: gear is designed for vacuum heat treatment of materials with melting point up to 2000 C. Gear includes at least one heating section with spiral made of carbon-carbon composite material, workpiece 6 of starting material placed in holders, heat insulation 4, 5 made of carbon-carbon composite material, screen-vacuum heat insulation 8, 9. Circular groove 12 and radial grooves 11 arranged in staggered order are made in heat insulation 4 to remove gases. Grooves provide for slow leveling of partial pressure of carbon in hot zone with outside vacuum. Gear is reliable in operation and shows long-term service life in process of heat treatment of materials at temperatures up to 2000 C thanks to manufacture of heat insulation from material similar to material of spiral made of carbon. EFFECT: increased operational reliability and prolonged service life of gear. 2 dwg