Discussion on Relationship Between Viscosities of Molten Zr-Cu Based Alloys and Their Glass Forming Ability

摘要

The dynamic viscosities of molten Zr_(55)Ni_5Al_(10)Cu_(30) and Zr_(50)Cu_(50) alloys were measured by using rotating cylinder method under non-vacuum condition. According to the lnη～1/T curves, discontinuous changes were found and the activation energy was calculated. The activation energy of molten Zr_(55)Ni_5Al_(10)Cu_(30) alloy is obviously larger than that of molten Zr_(50)Cu_(50) alloy. Amorphous sample of Zr_(55)Ni_5Al_(10)Cu_(30) with 3mm diameter was prepared successfully under non-vacuum condition, but there are crystallization phases in Zr_(50)Cu_(50) amorphous sample with 2mm diameter. The relationship between viscosities of molten Zr-Cu based alloys and their glass forming ability (GFA) was discussed, and viscosities of molten Zr-Cu based alloys play an important role on their GFA.