Ultra-high elevated temperature strength of TiB2-based ceramics consolidated by spark plasma sintering

Spark plasma sintering of TiB2-boron ceramics using commercially available raw powders is reported. The B4C phase developed during reaction-driven consolidation at 1900 degrees C. The newly formed grains were located at the grain junctions and the triple point of TiB2 grains, forming a covalent and stiff skeleton of B4C. The flexural strength of the TiB2-10 wt.% boron ceramic composites reached 910 MPa at room temperature and 1105 MPa at 1600 degrees C. Which is the highest strength reported for non-oxide ceramics at 1600 degrees C. This was followed by a rapid decrease at 1800 degrees C to 480-620 MPa, which was confirmed by increased number of cavitated titanium diboride grains observed after flexural strength tests. (C) 2016 Elsevier Ltd. All rights reserved.