NEUTRON-DIFFRACTION INVESTIGATION OF STRUCTURAL-CHANGES DURING INVERSE MELTING OF TI45CR55

The inverse-melted amorphous phase of Ti45Cr55, as well as the precurs or bcc phase has been investigated using neutron scattering. An increa se in chemical short-range order (CSRO), which involves primarily a di fferentiation of Ti and Cr sites in the alloy is detected, in line wit h expectations based on a decrease in the entropy which accompanies th e crystalline to amorphous (c-to-a) transformation. The CSRO in the am orphous phase shows a weak preference for unlike neighbor pairs. The n eutron data indicate that similarities exist between the local structu re 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 .