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Effect of the aluminum content on the behavior of mechanochemical reactions in the WO3–C–Al system

“…Sudden changes in XRD pattern of milled powder after 30 min indicate that the reaction mode is MSR. Rapid rise of T out and presence of W 2 C phase (which is stable at high temperatures [18]) could be taken as evidences of high temperatures caused by the heat of reactions. In this group, increased temperature has encouraged the carbide formation reactions (see Figs.…”

“…-At high temperatures resulted from MSR mode reactions, W 2 C is thermodynamically more stable than WC [18]. -Occurrence of carbothermic reaction, which is activated by the heat of aluminothermic reaction, consumes carbon and causes carbon deficiency in the system.…”

Control of carbon loss during synthesis of WC powder through ball milling of WO3–C–2Al mixture

“…-At high temperatures arising from MSR mode reaction, W 2 C is thermodynamically more stable than WC [16]. -At high temperature resulted from MSR mode reaction, carbon deficiency occurs which leads to the formation of W 2 C instead of WC [8,11].…”

Formation of Al2O3–WC powders from Al–WO3–C mixtures

“…It can be seen that reactions (2) and (3) have a negative DG 0 , indicating that both reactions are thermodynamically feasible. That is why it is difficult to produce high pure WC powders.…”

“…Therefore, W 2 C is linked with a transient intermediate during the formation of WC. For example, Zhang et al 2 have found the conversion of W 2 C into WC. Martin et al 3 also observed similar phenomena in the study on copyrolysis of polysilane and metallic tungsten.…”