Synthesis of tungsten nanopowders: Comparison of milling, SHS, MASHS and milling-induced chemical processes

Toxicological Assessment of ITER-Like Tungsten Nanoparticles Using an In Vitro 3D Human Airway Epithelium Model

“…ITER-like W-NPs have been produced by high energy planetary ball milling with tungsten carbide balls and a jar, a ball-to-powder ratio (BPR) of 40:1 and at a velocity of 350 RPM for a duration of 14 h in ethanol, as previously described [21]. Commercial W, showing 99.9% of purity and particle size 3–12 µm, was used as raw powder material (Alfa Aesar, Karlsruhe, Germany).…”

“…Therefore, the aim of this study was the in vitro evaluation of the toxicity and the lung absorption of non-tritiated ITER-like milled W-NPs. Since the ITER tokamak is not yet operating, the W-NPs used in this study have been bench synthesized and characterized [21,22]. We have investigated the behavior and the toxic potential of ITER-like W-NPs produced by planetary milling and we have compared them to particulate tungsten carbide alloy doped with cobalt (WC-Co) and to tungstate (WO 4 2− ) a non-particulate form to compare the speciation of W-NPs in lung.…”

SHS Synthesis and SPS Densification of Nanometric Tungsten

“…Following our previous works on the powder synthesis of small W samples (< 5 g), small (< 20 g) and larger (50 g) MoNbW alloys, our aim is therefore to develop a new path based on powder metallurgy to synthesize tungsten nanopowders using the Self‐propagating High‐temperature Synthesis (SHS) process, followed by Spark Plasma Sintering (SPS). Samples are characterized using XRD, SEM observations including the use Electron Back Scattered Diffraction (EBSD) technique, and hardness measurement.…”

“…Powder synthesis is performed using Self‐propagating High‐temperature Synthesis, using thermite‐like reactions, according to the same protocol as in refs . This method has been chosen for its relative ease for scaling‐up and possible extension of the protocol to tungsten alloys.…”

“…For the reaction to be complete, Mg amounts are increased from the stoichiometric proportions by 50%, and NaCl is added in order to decrease the overall products final temperature to 1800 °C; however, temperature is not measured during the reaction, the estimate of 1800 °C resulting from thermodynamic calculations. Note that NaCl is also known to favor nanometric grain sizes, although whether this results from an increase in grain germination or from a decrease in grain growth kinetics is not clear. Resulting products are then lixiviated using 2N hydrochloric acid for 2 h under stirring at 80 °C, in order to dissolve NaCl and MgO, then filtered using a 0.22 μm polyethersulfone membrane (MB Express Millipore®), rinsed, and dried.…”