An Investigation of Several Nb-Ti-Al Based Alloys on Microstructure

Several Nb-Ti-Al based alloys have been investigated by X-ray diffraction (XRD) and optical microscope (OM). It was found that the morphology of the B2/β phase was different from the O phase (Ti2AlNb) and δ phase (Nb3Al). The B2 phase can not be separated from the disordered β phase by metallography and XRD easily. And the typical morphology of O phase alloy is large herringbone structure. After that the aberrance of the lattice parameters was discussed in this article. The present result indicates in these alloys the lattice parameters were mainly determined by the ratio of Nb to Ti. As the ratio of Nb to Ti in alloys increased, the lattice parameters increased too.