SMALL-ANGLE NEUTRON-SCATTERING OF PHASE-SEPARATION IN AMORPHOUS ZR41TI14CU12.5NI10BE22.5 ALLOY

Phase separation in the amorphous Zr41Ti14Cu12.5Ni10Be22.5 alloy annea led at 620 and 643 K has been investigated by means of the in situ sma ll-angle neutron scattering (SANS) technique. The alloy decomposes int o two supercooled liquid phases, with the volume fraction of about 10- 20% for the second phase. The interphase boundary causes q(-4) scatter ing behaviour. The phase separation rate depends strongly on temperatu re, with a rather sluggish coarsening in the late stage. The kinetic e xponent of this coarsening stage was found to be about 0.06, to be com pared with the Lifshitz-Wagner exponent, 0.33.