Utilizing mixtures of yttria,magnesia,and lanthanum oxide in manufacture of transparent alumina
Abstract
Abstract A METHOD OF MANUFACTURING A POLYCRYSTALLINE TRANSLUCENT ALUMINA CONSISTING OF A HIGH PURITY ALUMINA AND HAVING EXCELLENT OPTICAL TRANSMISSION PROPERTY FOR THE LIGHT IN THE VISIBLE SPECTRUM, THERMAL SHOCK RESISTANCE AND MECHANICAL STRENGTH WHICH COMPRISES THE FOLLOWING STEPS CALCINING ALUMINA POWDERS HAVING A PURITY OF MORE THAN 99.00% BY WEIGHT AS A STARTING MATERIAL AT A TEMPERATURE OF 1,050-1,0250*C. IN AIR, ADDING TO SAID ALUMINA POWDERS 0.05-0.5% BY WEIGHT OF Y2O3, 0.05-0.5% BY WEIGHT OF LA2O3 AND 0.01-0.1% BY WEIGHT OF MGO, MIXING AND THEN MOLDING SAID ALUMINA POWDERS ADDED WITH SAID ADDI- TIVES, SINTERING AT FIRST SAID MOLDED MIXTURE AT A TEMPERATURE OF 1,200-1,450*C. AND SECONDLY SINTERING IN VACUUM OR A REDUCING ATMOSPHERE SUCH AS HYDROGEN OR DISSOCIATED AMMONIA GAS AT A TEMPERATURE OF 1,60001,800*C.
Inventors
- 👤 K Kobayashi
- 👤 M Kaneno
Bibliographic Details
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