Reaction and phase separation mechanisms during synthesis of alloys by thermite type combustion reactions

Abstract

Combustion of the thermite system is a promising approach for synthesis of alloys (e.g., Co-based) that are widely used in orthopedic applications. This process typically involves formation of two liquids (oxide and metal alloy), followed by their phase separation. The latter is generally believed to be controlled solely by gravity-driven buoyancy. To verify this hypothesis, a fundamental study of phase separation during alloy synthesis was conducted in both normal gravity and microgravity conditions. It was shown that a non-gravity-driven mechanism primarily controls the segregation process. Quenching experiments identified the reaction and phase separation mechanisms in the investigated systems.