Self-Propagating High-Temperature Synthesis of Ti6Al4V Alloy via Al-Driven Co-Reduction

The Ti–6Al–4V alloy was prepared by self-propagating high-temperature synthesis (SHS) through aluminothermic reduction of V2O5. Guided by thermodynamic analysis, the combustion behavior of 0.9TiH2 + 0.019V2O5 + xAl + yKBrO3 mixture was investigated at 0.5 MPa argon pressure. Aluminum served both to reduce vanadium oxide and to supply the required alloying component to Ti–6Al–4V alloy. A self-sustaining combustion reaction was achieved only with the addition of potassium bromate (KBrO3) as an auxiliary oxidizer. Optimal conditions of Ti–6Al–4V alloy synthesis were established using the composition 0.9TiH2 + 0.019V2O5 + 0.177Al + yKBrO3, with y ranging from 0.04 to 0.05. Within this range, combustion temperatures reached 1250–1350°C. By-products (KBr, Al2O3) of the combustion were removed by basic leaching. The synthesized alloy was characterized by X-ray diffraction analysis, particle size analysis, and scanning electron microscopy.