Development of Low Density CaMg-A1-Based Bulk Metallic Glasses (Preprint)

摘要

Low density Ca-Mg-Al-based bulk metallic glasses containing additionally Cu and Zn, were produced by a copper mold casting method as wedge- shaped samples with thicknesses varying from 0.5 mm to 10 rom. The compositions of the alloys were selected using recently developed specific criteria for glass formation. A structural assessment using the efficient cluster packing model was also applied and showed a good ability to represent these glasses. Thermal properties of the new metallic glasses, such as the glass transition, crystallization and melting temperatures, as well as heats of crystallization and melting are reported. The critical cooling rate for amorphization and the fragility index are estimated for these alloys. The effect of the alloy composition on glass forming ability is discussed.