The alloy systems uranium-tungsten, uranium-tantalum and tungsten-tantalum

Bridging the opposite chemistries of tantalum and tungsten polyoxometalates.

The disparate solubility, redox activity, and pH stability of the group V and group VI polyoxometalates (POMs) confer very different functionality on these species, and tailoring cluster properties by varying the ratio of group V to group VI metals poses both an opportunity and a synthetic challenge. A classic series of studies reported over 40 years ago provided some insight into W/Nb POMs, fr...

High-temperature tantalum tungsten alloy photonic crystals: Stability, optical properties, and fabrication

The Welding and Brazing of the Refractory Metals Niobium, Tantalum, Molybdenum and Tungsten - a Review*

This review covers the present and future problems in the development and welding of niobium, tantalum, molybdenum and tungsten and their alloys. Their metallurgical characteristics are discussed together with the influence of impurities and alloying elements on mechanical properties, alloy development and weldability. Other factors briefly discussed are availability, high temperature strength,...

Tensile and compressive behavior of tungsten, molybdenum, tantalum and niobium at the nanoscale

In situ nanomechanical tests are carried out to investigate the tensile and compressive behavior of h0 0 1i-oriented body-centered cubic (bcc) metals W, Mo, Ta and Nb with nanometer dimensions. We find that the strength of these metals exhibits strong size dependence. The compressive size effect in Nb, as evaluated by the log–log slope of strength vs. nanopillar diameter, is 0.93, a factor of 2...

The influence of tungsten alloying on the mechanical properties of tantalum

In mechanical tests of tantalum-tungsten alloys with nominal tungsten contents between 0 and 10 wt% for strain rates between 0.000016 and 6800 sr and temperatures between 77 and 400 K, the addition of tungsten noticeably reduces the strain-rate dependence of the flow stress of tantalum near yield. It also subtly alters the strain-rate behavior of the work hardening, making it more like that of ...