Studies on Direct Carburization of (WTi)C from the Mixture of WO₃, TiO₂ and C

Abstract

The direct carburization of (WTi)C, using WO₃ powder as a starting material, is not industrialized owing to many quality problems.
Therefore, in this paper the possibility of (WTi)C carburization from the mixture Of WO₃, TiO₂ and C was examined, As a result, a new process in which the mixture is first heated in N ₂ and then re-heated in H₂ at higher temperature was presented. By this process, (WTi)C powders of good quality, fine, and uniform grain size were obtained and the alloy made of this powder showed good properties.
The process of each reaction stage was studied. By the first heat treatment in N ₂, WO₃ was reduced by carbon to fine WC powder, and TiO₂ was changed into Ti(NCO) containing a lot of nitrogen.
By the second heat treatment in H₂ at higher temperature, N ₂, O ₂ and H2 gas contained were completely removed from (WTi)C solid solution by the reaction between WC and TiC.