Optimize The Composition Of The Zr-al-ni-cu Bulk Amorphous Alloys

The present thesis aims at the composition optimization for the largest glass-forming ability (GFA) in the Zr-Al-Ni-Cu quaternary alloy system, by adopting the two empirical parameters, electron concentration (e/d) and average atomic size (Rav), proposed in our previous work. Six series, totally 42 compositions are designed; samples are prepared by arc-melting and suction cast method. The amorphous nature was examined by X-ray diffraction, and using differential scanning calorimeter and differential thermal analysis has carried out thermal analysis.XRD and thermal analysis results indicate that the optimized composition ,which has the largest glass forming ability is Zr58Al13Ni11Cu15, locating in the series with e/a=1.5, Rav = 0.1486nm. This composition has the largest Y = 0.426, Tg/ Tl= 0.622.According to the exam results, electron concentration (e/d) and average atomic size (Rav) have an obvious and regular influence of GFA in Zr-Al-Ni-Cu system. The two parameters are desirable composition design criteria leading to the ideal bulk amorphous composition.