Crystal nucleation and time evolution during isothermal annealing in amorphous Zr2Ni at several temperatures just below a crystallization temperature Tx and in supercooled liquid of metallic glass Zr 2Cu are examined using a technique of differential thermal analysis. Time dependence of the fraction of crystallization at several temperatures is analyzed by the Johnson-Mehl-Avrami equation. The Avrami exponent is 3.0 ±0.2 for Zr2Ni and varies from about 3 to 7 for Zr 2Cu with increasing temperature. It is suggested for Zr2Ni that the crystal growth at temperatures just below Tx is ruled by a short range diffusion process of constituent elements. The time evolution of crystallized fraction was not well scaled by the half of complete time for full crystallization.
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