Fabrication of finegrained Al2O3 ceramic at low sintering temperature
(1. State Key Laboratory for Corrosion and Protection, Institute of Metal Research,
Chinese Academy of Sciences, Shenyang 110016, China;
2. Graduate School of Chinese Academy of Sciences, Beijing 100039, China;
3. Shenyang Institute of Automation, Chinese Academy of Sciences,
Shenyang 110016, China)
Chinese Academy of Sciences, Shenyang 110016, China;
2. Graduate School of Chinese Academy of Sciences, Beijing 100039, China;
3. Shenyang Institute of Automation, Chinese Academy of Sciences,
Shenyang 110016, China)
Abstract: A research on fabrication of finegrained Al2O3 ceramic at lower sintering temperature was carried out. Al2O3 powder with 50nm in diameter is compounded with 11.24%Al and 4.75%Fe(mass fraction) by high-energy ball-milling. Al is got from Al powder which is a component of the materials being milled and Fe from steel milling balls and milling jar during the milling. In this way, nearly no impurity is brought into the composite powder during milling. With hot pressing of the composite powder and pure Al2O3 powder, it is proved that Al2O3 powder can be densified at lower sintering temperature when the powder is compounded in this way. Al2OC and AlFe form during sintering process of the composite powder. With the reactive sintering and multiphase sintering mechanisms, finegrained Al2O3 ceramic is fabricated at low sintering temperature.
Key words: finegrained Al2O3 ceramic; sintering; nanometer Al2O3-Al-Fe composite powder; high-energy ball-milling; strength; toughness