Effects of process parameters on tungsten. boride production from WO3 by self propagating high temperature synthesis


Yazici S., Derin B.

MATERIALS SCIENCE AND ENGINEERING B-ADVANCED FUNCTIONAL SOLID-STATE MATERIALS, cilt.178, sa.1, ss.89-93, 2013 (SCI-Expanded) identifier identifier

Özet

In the present study, the production parameters of tungsten boride compounds by self-propagating high-temperature synthesis (SHS) method and following leaching process were investigated. In the SHS stage, the. products consisting of tungsten borides, magnesium oxide, magnesium borate, and also minor compounds were obtained by using different initial molar ratios of WO3, Mg and B2O3 as starting materials. In the leaching step, Mg containing byproducts, i.e. MgO and Mg3B2O6, existed in the selected SHS product synthesized at 1:8:2.5 initial molar ratio of WO3:Mg:B2O3 were leached out by using aqueous HCl solution to obtain clean tungsten boride compounds at different experimental parameters which are time, acid concentration and temperature. The acid leaching experiments of the SHS product showed that optimum leaching conditions could be achieved by using 5.8 M HCl at 1/10 S/L ratio and the temperature of 80 degrees C for 60 min. (C) 2012 Elsevier B.V. All rights reserved.