ZrB2 grains synthesized on graphite by chemical vapor deposition

ZrB2 grains were prepared on graphite by chemical vapor deposition using a gas mixture of ZrCl4, BCl3, H-2 and Ar at 1150 degrees C. The microstructure and phase composition of the coating were investigated by SEM, XRD, XPS and TEM. The results indicated that ZrB2 grains were deposited and grown directly by a vapor -solid growth mechanism on graphite without intermediate phase. Granulated ZrB2 grains were composed by many sub-grains with different crystal orientation. The rod-like or pagoda-like ZrB2 grains with lamellar structures were grew on the granulated ZrB2 particles and composed of two parts: the internal part with axial stacking faults and annular part with radial stacking faults. (C) 2016 Elsevier B.V. All rights reserved.