Assessment of mechanical properties of SPS-produced tungsten including effect of neutron irradiation

Production and supply of tungsten for the first wall fusion application is becoming an important aspect given the progress of ITER construction. Exploration of advanced routes alternative to the conventional powder metallurgy is currently undertaken. In this work we have assessed a potential of the spark plasma sintering (SPS) production route to deliver well controlled microstructure, chemistry and mechanical properties of bulk tungsten as a first step. SPS-produced tungsten was sintered at 2000 °C and was characterized in terms of mechanical properties, namely: tensile, three point bending and fracture toughness data in the temperaure range of 250–600 °C. Then, neutron irradiation was performed at 600 °C and the change of the fracture toughness was measured after irradiation together with the characterization of the fracture surface. The results are compared with those obtained for the commerically produced swaged tungsten irradiated and tested in equivalent conditions. The obtained results show that SPS technology offers the production of bulk tungsten with a good potential for further optimization (by e.g. swaging/rolling). Neutron irradiation causes the reduction of the fracture toughness comparable to the one induced in the commercially produced tungsten

ITER Langmuir probes: Physics and technological issues under investigation in the WEST tokamak

International audienc

Determination of sterols and steroid hormones in surface water and wastewater using liquid chromatography-atmospheric pressure chemical ionization-mass spectrometry

The development and optimization of an analytical method for simultaneous extraction, determination and reliable confirmation of twenty steroids from different classes (human/animal and plant sterols, and natural and synthetic steroid hormones) in environmental water and wastewater at ng L-1 levels are described. Water samples were prepared using solid-phase extraction and extracts were analyzed by liquid chromatography-linear ion trap-tandem mass spectrometry. Improved instrumental method was developed for complete chromatographic separation of analytes with identical fragmentation reactions, based on the Use of a single C8 column and acetonitrile as organic solvent in the mobile phase. The optimized method provided high recoveries (70-114%) for both water matrices with the RSDs generally lower than 20%. Low limits of detection were achieved for both surface water (0.7-15.0 ng L-1) and wastewater (1.7-15.0 ng L-1). Method displayed good linearity in the tested concentration ranges. As a result of method application to real water samples, cholesterol was detected in all fifteen analyzed river water samples (in the concentration range 176-5162 ng L-1) and all seven wastewater samples (1092-4808 ng L-1). Also, coprostanol, stigmasterol, campesterol, beta-sitosterol and sitostanol were found in the investigated samples. Steroid hormones were not detected in any of the analyzed water samples