Fe-Ni-Ti (Iron-Nickel-Titanium)

The phase diagrams of iron-nickel-titanium (Fe-Ni-Ti) ternary system were reported. The Fe-Ni phase diagram was characterized by a very narrow solidification range with a reaction at 1514 °C, between bcc δ (or α) and liquid that yielded the Fe-based fcc solid solution. The Fe-Ti phase diagram depicted two intermediate phases such as Fe 2Ti and FeTi. The Ni-Ti phase diagram had three intermediate phases such as Ni 3Ti, NiTi and NiTi 2. The intermetallic phases such as NiTi 2, NiTi, Ni 3Ti, FeTi and Fe 2Ti were modeled with two or more sublattices with provision for the ternary solubility, which was appreciable in the phases. The two metastable isothermal sections at 700 °C depicted the equilibria between the ordered and disordered forms of bcc and fcc respectively were also computed.