Tungsten-nickel-iron non-crystalline alloys: Thermal stability and consolidation behavior

A W-Ni-Fe non-crystalline material has been developed via mechanical alloying. Its microstructure is characterized by nano-sized W particles embedded in a W-Ni-Fe glassy matrix. This work focuses on the thermal stability of the glassy phase and consolidating the as-milled powder materials into fully dense materials.; The phase transformations occurring during the crystallization of the glassy phase have been investigated. The crystallization process is influenced by the initial compositions and milling time. The heat of mixing of Ni-W binary glassy phase was estimated in this work. The results have shown that glass forming ability of Ni-W binary alloy had been underestimated. The W content in the glassy phase is found to be an important kinetic factor influencing the glassy phase stability.; The materials having the highest crystallization temperature have been defined. They have been consolidated via two approaches: (1) dynamic compaction, (2) liquid phase sintering. The preliminary evaluations of the consolidated materials are presented.