Novel Insight into the Preparation of Ti-6Al-4V Alloy Through Thermite Reduction Based on the Mass Action Concentration

Abstract

Based on the mass action concentration theory, a novel thermodynamic analysis for the raw material ratio in the procedure of preparing Ti−6Al−4V alloy by aluminothermic reduction process is proposed in this paper, which is originated from TiO₂, Al particles, and V₂O₅ as feedstocks, and the relevant equilibrium thermodynamics was calculated through this new method. The results show that the range of aluminum addition coefficient in raw material to experiment should be controlled within 61.5%–100%, which can significantly reduce the number of experimental groups. This method is ready to regulate the matter of excessive aluminum content in reactants for materials preparation, especially for those reactions including elements that are effortless to combine with aluminum to form the corresponding intermetallics or alloys. In addition, it can also be used in general metallurgy or material preparation process to effectively predict the composition and proportion of equilibrium components under certain conditions.

Keywords

mass action concentration / titanium alloy / thermodynamics / intermetallics / thermite reduction

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