Spark plasma synthesis and densification of TaB_2 by pulsed electric current sintering

摘要

The synthesis and consolidation in one processing step of single phase tantalum diboride by Spark Plasma Sintering (SPS) is proposed. TaB_2 formation from Ta and B elemental powders takes place at about 800 °C through a solid-state combustion reaction while product densification requires higher temperatures. Consolidation is significantly improved (-96% density) when increasing the applied pressure from 20 to 60 MPa immediately after the synthesis reaction occurs. Simplicity, short duration, milder temperatures and pressure conditions, in comparison with other routes utilized so far for obtaining bulk TaB_2 are, along with the good mechanical properties of the obtained product, the main benefits of the adopted approach.