Glass formation in Zr-Al-Fe-Cu system

Aimed at developing new Ni-free Zr-based bulk metallic glasses (BMGs), a series of Ni-free Zr-Al-Fe-Cu glass formers have been developed in this work. The compositions are designed by using a combination of clusters and mixing entropy. Glass formers in this system are considered to be a mixture of Zr-Al, Zr-Fe and Zr-Cu clusters. Their coefficients were obtained by the calculation of mixing entropy. Under the guidance of this method, a series of compositions with high glass forming ability (GFA) were developed. Among the glass formers, the alloy compositions of Zr60.32Cu22.56Fe9.95Al7.17 and Zr64.08Cu18.78Fe10.02Al7.12 possess the highest GFA. Glassy rods can be fabricated at these two compositions with critical diameter up to 5 mm, which is superior to that reported for the known Zr60Cu25Fe5Al10 BMG under the same condition.