Recently reported results on the behaviour of the tungsten under conditions expected in the Neutrino Factory target have strengthened the case for a solid target option for the Neutrino Factory. This paper gives a description of the measurements of the surface motion of tungsten wires, stressed by a pulsed current, using a Laser Doppler Vibrometer in order to measure tungsten properties at high...

Gas tungsten arc welding (GTAW), also known as tungsten inert gas (TIG) welding, is an arc welding process that uses a nonconsumable tungsten electrode to produce the weld. The weld area is protected from atmospheric contamination by a shielding gas (usually an inert gas such as argon), and a filler metal is normally used, though some welds, known as autogenous welds, do not require it. A const...

Atomically sharp tungsten tips made from single crystal tungsten wire are superior to those made from cold-drawn polycrystalline wire but are rarely used due to their high price. We have devised a method of obtaining highly crystalline tungsten wire by recrystallizing cold-drawn wire. The effect of various heat treatments on the wire microstructure was observed using scanning electron microscop...

Recently reported results of the high strain rates, high temperature measurements of the yield stress of tungsten and tantalum have been analyzed. The highest temperature reached in the experiment, based on heating and stressing a thin wire by a fast, high current pulse, was 2250 C and 2450 C, for tantalum and tungsten, respectively. The strain-rates in both the tungsten and tantalum tests were...

A two-stage sintering practice was applied to W­3.99Ni­1.71Fe (mass%) to control its microstructural evolution and, accordingly, mechanical properties under high strain rates. Unlike the traditional one-stage liquid phase sintering, the alloy was first solid-state-sintered to close to full densification, and then liquid-phase-sintered by induction heating where the cooling rate was fast. With t...

The ITER reference materials have been tested separately in tokamaks, plasma simulators, ion beams and high heat flux test beds. In order to perform a fully integrated material test JET has launched the ITER-like Wall Project with the aim of installing a full metal wall during the next major shutdown. As a result of R&D projects in 2005–2006, bulk tungsten tiles are foreseen at the outer horizo...

PURPOSE Due to the current interest in MRI-guided radiotherapy, the magnetic properties of the materials commonly used in radiotherapy are becoming increasingly important. In this paper, measurement results for the magnetization (BH) curves of a range of sintered heavy tungsten alloys used in radiation shielding and collimation are presented. METHODS Sintered heavy tungsten alloys typically c...

To evaluate a possible influence of confounding in risk estimation for lung cancer in relation to silica dust exposure, we re-analyze a recently published exposure-response relationship using a sub-cohort of Chinese tungsten miners which has no relevant occupational confounders. The cohort of tungsten miners consisted of 19,007 workers in six tungsten mines with a follow-up period from January ...

The tungsten-iron-sulfur enzyme acetylene hydratase stands out from its class because it catalyzes a nonredox reaction, the hydration of acetylene to acetaldehyde. Sequence comparisons group the protein into the dimethyl sulfoxide reductase family, and it contains a bis-molybdopterin guanine dinucleotide-ligated tungsten atom and a cubane-type [4Fe:4S] cluster. The crystal structure of acetylen...

The effect of tungsten erosion, transport, and redeposition on the operation of dispenser hollow cathodes was investigated in detailed examinations of the discharge cathode inserts from 8200 h and 30 352 h ion engine wear tests. Erosion and subsequent redeposition of tungsten in the electron emission zone at the downstream end of the insert reduce the porosity of the tungsten matrix, preventing...