PROCEDURE FOR PRODUCTION OF HIGH PURITY MOLYBDENUM FOR SPUTTERING TARGET Russian patent published in 2011 - IPC C22B34/34 C22B3/24 C22B9/20 

FIELD: metallurgy.

SUBSTANCE: procedure consists in purification of solution of ammonia paramolybdate form impurities by ion exchange in neutral and sub-alkali mediums on hydrated oxide of tin and on sub-basic anionite AN-106. Further, ammonia paramolybdate is thermally decomposed at temperature 600-800°C to production of molybdenum oxide and is refined by zone sublimation at temperature 750-800°C in continuous flow of oxygen. Molybdenum oxide is heterogeneous reduced with hydrogen at temperature 700-750°C till production of powder of molybdenum. Powder is compressed to a rod which is subjected to electronic vacuum zone re-crystallisation till production of high purity molybdenum crystal. Molybdenum crystals are melt in electron vacuum in a flat crystalliser with melt of flat ingot of high purity molybdenum on each side at total depth not less, than twice. A molybdenum rod is treated with chlorine prior to zone re-crystallisation at rate of chlorine supply 100 ml/min and temperature 300°C during 1 hour.

EFFECT: great rise of molybdenum purity.

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