| Summary: | The crystallization transformation in Zr-Cu-Ag metallic glasses have been comparatively studied. The crystallization enthalpy ΔHx lies in the range of −56.18 ∼ −46.90 J/g for Zr50Cu38Ag12 metallic glass and −55.69 ∼ −44.70 J/g for Zr50Cu36Ag14 metallic glass in their respective isothermal temperatures. The average crystallized volume fraction fmax corresponding to the maximum value of transformation rate [df/d(tIso − τ)]max is about equal to 0.52 and 0.55 for Zr50Cu38Ag12 and Zr50Cu36Ag14 metallic glasses. It is found that at the same isothermal temperature, [df/d(tIso − τ)]max becomes smaller, the time–temperature-transformation (TTT) diagram shifts to the right and time tmax required to reach [df/d(tIso − τ)]max becomes longer when Cu is replaced with Ag, which indicates that the thermal stability will be improved as Ag content rises in these metallic glasses. In addition, the type of growth is interface-controlled growth for Zr50Cu38Ag12 and Zr50Cu36Ag14 metallic glasses.
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