Solid State Science and Technology, Vol. 18, No 2 (2010) 91-98
THE PRODUCTION OF HfO2-HfB2 COMPOSITE POWDER FROM
HfO2, B2O3 AND Mg BY SOLID STATE REACTION
AND SUBSEQUENT ANNEALING
Ozge Balci, Duygu Agaogullari and Ismail Duman
Istanbul Technical University, Department of Metallurgical and Materials Engineering, Maslak 34469, Istanbul, Turkey
Hafnium dioxide-hafnium diboride (HfO2-HfB2) composite powder was synthesized by high-energy ball milling and subsequent annealing of powder mixtures containing stoichiometric amounts of HfO2, B2O3 and Mg. Milling was carried out in various durations by using vibratory ball-mill with a ball-to-powder weight ratio of 10:1. The milled products were annealed in tube furnace with a heating and cooling rate of 10°C/min. under flowing Argon atmosphere. After annealing, the HfO2-HfB2 composite powder is obtained in the presence of magnesium oxide (MgO). The milled and annealed products were analyzed by X-ray diffraction (XRD) technique and scanning electron microscope (SEM).
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