Impurity control in pressureless reactive synthesis of pure Ti_3SiC_2 bulk from elemental powders

摘要

The impurity control in pressureless reactive synthesis of pure Ti_3SiC_2 from elemental powders is reported. Ti_3SiC_2 bulk samples were prepared by sintering compacts of ball-mixed elemental powders at 1500 °C for 2 h in lidded alumina crucibles under Ar atmosphere. Undesirable TiC impurity was successfully eliminated from the synthesized product. Product with desired phase constituent can be fabricated by preparing samples according to phase diagram data. Keeping away from the phase fields that involve TiC is a vital way to obtain pure Ti_3SiC_2 without containing the undesirable TiC. The key for successful impurity control in the sintering process is the conservation of mass in the reactants.