Accessory graphite equipment
with high-density W coatings

Application of graphite in the industrial equipment used for various high-temperature chemical-technological processes, restrains because of created by it impurities background polluting final production.
Such problems, for example, exist in manufacture of semi-conductor monocrystals (arsenide of gallium, silicon, germanium), monocrystals sapphire, a ruby, etc.
The new constructional materials developed by us on the basis of graphite with protective coatings will help with the decision of these problems.
The carried out industrial tests have shown, that application of graphite thermal unit with a protective tungstin coating of all of its parts at melt growth monocrystals of arsenide of gallium (MAG) allows to lower imuprity background in the MAG (in comparison with the MAG, brought up in thermal unit without a coating) on carbon, iron, cobalt, copper, chromium, to silicon approximately twice (thus tungsten as an impurity in the MAG is not found out), and also to increase electrophysical characteristics the MAG and a resource of work of thermal unit.