Study of the aluminothermic reduction of niobium pentoxide through thermal analysis experiments and high energy milling processing

Materials Research

Claudio Parra De Lazzari¹  Danielle Goya Simões¹  José Deodoro Trani Capocchi¹ 

[1] ,University of São Paulo Polytechnic School Department of Metallurgical and Materials EngineeringSão Paulo SP ,Brazil

关键词: aluminothermy;    niobium pentoxide;    thermal analysis;    high energy milling;   

DOI  :  10.1590/S1516-14392007000200020

来源: SciELO

【 摘 要 】

Aluminothermic reduction of niobium pentoxide was studied through thermal analysis techniques such as differential thermal analysis (DTA) and thermogravimetry (TG) as well as through high energy milling processing. Reactants mixtures were composed by powders of Nb2O5 and Al. In the case of DTA-TG experiments, different molar ratios Nb2O5:Al were heated in a dynamic atmosphere of synthetic air under controlled conditions. The high energy milling runs were carried out via SPEX vibratory mill under argon atmosphere and with milling power equal to 7:1 (ratio of mass of balls to mass of mixture) with 10 pct excess of Al over the stoichiometric mass of aluminum necessary. In both kinds of experiments, X ray diffraction was used in order to identify the products of reaction. From DTA-TG experiments, it was possible to determine the experimental value of the enthalpy change (-595.9 kJ.mol-1), which is near to the theoretical one. From the milling experiments, it was possible to verify the possibility of the occurance of aluminothermic reducion of niobium pentoxide via this kind of processing.

【 授权许可】

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