Consolidation and grain growth of tantalum diboride during spark plasma sintering

Bulk tantalum diboride ceramics have been consolidated by spark plasma sintering (SPS) at 1700-2200 degrees C using moderate pressure of 30 MPa. The effect of temperature and dwell time on the densification, microstructure and mechanical properties were investigated. SPS resulted in dense, crack-free specimens with strength ranging from 280 to 550 MPa. The room-temperature strength of TaB2 ceramics was analyzed as a function of the grain size. Activation energy for the grain growth process was estimated as 1078 +/- 31 kJ mol(-1). (C) 2016 Elsevier Ltd and Techna Group S.r.l. All rights reserved.