Design of new Zr-Al-Ni-Cu bulk metallic glasses

Five new Zr-Al-Ni-Cu bulk metallic glasses were designed by the average conduction electron concentration ela and average atomic radius R,, criteria on the condition of the weak constraint condition of melting heat Delta H-m. We investigated the relationships between critical dimension Z(max) and such parameters as ela, R-a, difference in atomic radius Delta R, Delta H-m, under-cooled liquid region Delta T-x reduced glass transition ternperature T-rg, K-gl and gamma. The results show that ela, Ra, Delta R and Delta H-m are all strongly related to glass-forming ability (GFA) of alloys. Zr62.5Al12.1CU7.95Ni17.45 owns best thermal stability and GFA among live new Zr-Al-Ni-Cu bulk metallic glasses. K-gl, and gamma are better than Delta T-x, and T-rg at the point of the description of GFA of alloys. In addition, the compositions of glass-forming alloys with best GFA do not locate at but near to eutectic point. (C) 2008 Elsevier BN. All rights reserved.