High-purity amorphous Zr52.5Cu17.9Ni14.6Al10Ti5 powders via mechanical amorphization of crystalline pre-alloys

✍ Scribed by Marco E. Siegrist; Michael Siegfried; Jörg F. Löffler

• Publisher: Elsevier Science
• Year: 2006
• Tongue: English
• Weight: 407 KB
• Volume: 418
• Category: Article
• ISSN: 0921-5093
• DOI: 10.1016/j.msea.2005.11.024

✦ Synopsis

Fully amorphous Zr 52.5 Cu 17.9 Ni 14.6 Al 10 Ti 5 (Vit 105) powder with very low oxygen contamination was successfully produced from pre-alloyed crystalline material. A yield of over 80% was achieved without the use of a milling agent. The amorphization process was observed by differential scanning calorimetry (DSC) and X-ray diffraction (XRD). The extremely fast amorphization rate was fitted by an exponential relaxation function. A partial time-temperature-transformation (TTT) diagram was obtained from isothermal annealing experiments based on the Johnson-Mehl-Avrami (JMA) model. In addition, the microstructure of the powder was observed by scanning electron microscopy (SEM), and gas analysis was conducted at various stages of the ball-milling process.