Orientation relationship in a Ti/TiB metal-matrix composite

The microstructure and orientation relationships (OR) of a Ti/TiB metal-matrix composite produced by spar plasma sintering (SPS) using a Ti-10 wt%TiB2 mixture at temperatures corresponding to either the alpha or the phase fields of titanium (850 or 1000 degrees C, respectively) was studied. During SPS, an in situ chemical reaction between TiB2 and Ti resulted in the formation of nanosized TiB whiskers. An increase in the SPS temperature caused a decrease in the fraction of the retained TiB2 and an increase in the diameter of the TiB whiskers. The mutual alpha-Ti and TiB phase orientation depended on the SPS temperature and did not necessarily correspom with the known OR. Corresponding orientations of phases in case of the sintering at temperatures greater the the alpha <->beta transition were calculated.