Preparation and microstructure of as-cast in-situ Ti-6Al/TiB composites

TiB reinforced titanium composites have been successfully synthesized by ad ding the Al/TiB2 master alloy into titanium alloy. The phase constituent an d the microstructure have been studied by XRD and SEM. Compared with the st andard values, the lattice parameter of TiB calculated from the XRD pattern indicates that the synthesized TiB is of prefect crystal structure. The mi crostructure has shown that high aspect ratio fibrous TiB has been found, w hich homogeneously distribute in the matrix in a random way. The size is ab out 100 mum in length, less than 2.5 mum in diameter and the aspect ratio i s greater than 40. Deep etched microstructures show that some coarse hollow TiB corresponding to primary TiB are also formed with smooth and flat surf ace and random transverse section. The size is about 100 mum in length and greater than 10 mum in diameter. The solidification process has also been a nalyzed.