Neutron-diffraction investigation of structural changes during inverse melting of Ti45Cr55

The inverse-melted amorphous phase of Ti45Cr55, as well as the precursor bcc phase has been investigated using neutron scattering. An increase in chemical short-range order (CSRO), which involves primarily a differentiation of Ti and Cr sites in the alloy is detected, in line with expectations based on a decrease in the entropy which accompanies the crystalline to amorphous (c-to-a) transformation. The CSRO in the amorphous phase shows a weak preference for unlike neighbor pairs. The neutron data indicate that similarities exist between the local structure of the inverse melted amorphous phase and the TiCr2 Laves compound. These similarities are indicative of topological medium-range order (MRO) in the amorphous phase which resembles that of the Laves compound.