Production of tungsten-boron based metallic glasses for advanced technological applications

Metallic glasses containing refractory metals such as Re, Ru, Ir, Rh, Os and W have quite high crystallization temperatures(Tx), which are between 1000-1400 K, and microhardness values, which are between 1300 and 1700 Hv. Among systems a tungsten based metallic glass having composition of W30Fe38B25C7 has crystallization temperature of 1067 K and microhardness of 1122 Hv. The most important advantage of tungsten with respect to the other refractory metals is that its cost is much lower. In the first stage of this study Fe-W-B alloys having iron contents between 35 and 45% were prepared. Thin foils, which have a thickness of about 30?m, of these alloys were prepared by piston and anvil method. Thermal and mechanical properties of these alloys were characterized. In the second stage of the study, titanium substituions for tungsten were made in a chosen Fe-W-B alloy. Thin foils of these alloys were also characterized to determine effect of titanium addition on thermal and mechanical properties of the alloys. For all of the thin foils of the alloys, structural characterization was carried out by X-ray diffraction (XRD) and crystallization, melting and liquidus temperatures were determined by differantial scanning calorimetry(DSC). Key Words: Metallic glass, Refractory metal, Crystallization temperature, Hardness