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[Display omitted] • Bioaccessibility of cobalt in stainless steels important from a legislative view. • Surface oxide and metal release of austenitic stainless steel 316L studied. • Metallic cobalt homogeneously co-located with nickel beneath the surface oxide. • Cobalt traces released with other metals upon surface reformation and passivation. • Surface enrichment of cobalt due to precipitation of released cobalt in PBS. Since 2021, cobalt (Co) is in Europe classified as carcinogen in quantities exceeding 0.1 wt-%. This affects nickel-rich stainless steels, which contain about 0.2 wt-% Co impurities. Previous findings show the bioaccessibility of Co in stainless steel to be primarily determined by the corrosion resistance. It has been unclear whether Co is distributed heterogeneously in the alloy and the outermost surface and whether a specific location would pose a risk for Co release under specific exposure conditions. This study aimed at locating Co in stainless steel 316L (0.2 wt-% Co) surfaces prior to and after exposure to different synthetic body fluids for 24 h at 37 °C. Time-of-flight secondary ion mass spectrometry (ToF-SIMS), X-ray photoelectron spectroscopy (XPS), and inductively coupled plasma mass spectrometry (ICPMS) investigated the location of Co in the surface oxide and extent of release along with other metals (iron, chromium, nickel, and manganese) into synthetic biological fluids (gastric fluid, pH 1.5; lysosomal fluid, pH 4.5; phosphate buffered saline-PBS, pH 7.4). Co was homogeneously distributed along with metallic nickel beneath the surface oxide and co-released with other metals upon surface reformation and passivation. Exposure in PBS resulted in the incorporation of both Co and phosphate in the oxide. [ABSTRACT FROM AUTHOR]

Abstract: Europe has developed two reference Tritium Breeder Blankets concepts for a DEMO fusion reactor: the Helium-Cooled Lithium–Lead and the Helium-Cooled Pebble-Bed. Both are using the reduced-activation ferritic–martensitic EUROFER-97 steel as structural material and will be tested in ITER under the form of test blanket modules. The fabrication of their EUROFER structures requires developing welding processes like laser, TIG, EB and diffusion welding often beyond the state-of-the-art. The status of European achievements in this area is reviewed, illustrating the variety of processes and key issues behind retained options, in particular with respect to metallurgical aspects and mechanical properties. Fabrication of mock-ups is highlighted and their characterization and performances with respect to design requirements are reviewed. [Copyright &y& Elsevier]

Abstract: EUROFER weldability is investigated in support of the European material properties database and TBM manufacturing. Electron Beam, Hybrid, laser and narrow gap TIG processes have been carried out on the EUROFER-97 steel (thickness up to 40mm), a reduced activation ferritic–martensitic steel developed in Europe. These welding processes produce similar welding results with high joint coefficients and are well adapted for minimizing residual distortions. The fusion zones are typically composed of martensite laths, with small grain sizes. In the heat-affected zones, martensite grains contain carbide precipitates. High hardness values are measured in all these zones that if not tempered would degrade toughness and creep resistance. PWHT developments have driven to a one-step PWHT (750°C/3h), successfully applied to joints restoring good material performances. It will produce less distortion levels than a full austenitization PWHT process, not really applicable to a complex welded structure such as the TBM. Different tungsten coatings have been successfully processed on EUROFER material. It has shown no really effect on the EUROFER base material microstructure. [Copyright &y& Elsevier]

Abstract: Vascular support structures are an important tool for treating valve stenosis. A large population of patients are treated for valvular disease and the principal mode of treatment is the use of percutaneous valvuloplasty. Stent devices are proving to be an improved treatment method; these devices now account for 20% of treatments in Europe. This new technology provides highly effective results at minimal cost and with reduced hospital stays. Accurate and reliable structural analysis provides essential information to the design team in an environment where in vivo experimentation is extremely expensive or impossible. This paper describes the design of a new vascular support structure (stent), to provide designers with estimates of the critical parameters which are essential. Stainless steel stents are preferred to be used as balloon-expanded prostheses as they are cost-effective. [Copyright &y& Elsevier]

Samples of high alloy Stainless Steel SS 1 were analyzed by instrumental neutron activation analysis (INAA) at 5 research institutes in 4 European countries within the frame of an Inter-Laboratory Comparison (ILC) exercise aiming at checking if the results were independent of the standardization methods, and if INAA was accurate enough to contribute to certification. The mean element concentration values yielded by INAA were also compared with mean values obtained by atomic emission spectroscopy techniques at other laboratories that took part in the International Proficiency Testing organized by KIMAB Institute of Sweden, producer of the SS 1. The performances of the nuclear and atomic techniques were compared in terms of the z-score values calculated for 11 element concentrations evaluated by the two analytical ways. Finally, consideration is given to the ways in which highest accuracy and precision can be ensured for certifying stainless steels as CRMs. [ABSTRACT FROM AUTHOR]

Abstract: This paper presents the last results obtained in the ITER First Wall (FW) development work programme performed in Europe on beryllium (Be), copper (Cu) alloys and 316L(N) stainless steel (SS) joining by Hot Isostatic Pressing (HIPping). It reports first the performances under high heat flux testing of CuCrZr/316L(N) SS mock-ups and compares them with those obtained earlier with CuAl25/316L(N) SS mock-ups. It reports then the results of the last developments done on Be/Cu alloy HIPped joints. In particular it presents the results of high heat flux testing of Be/CuCrZr FW mock-ups and compares them with those obtained earlier with Be/CuAl25 FW mock-ups. It gives the status of on-going thermal fatigue tests of Be/Cu alloy FW mock-ups and presents the result of a neutron irradiation experiment performed on Be/CuAl25 mock-ups. The results obtained so far with FW mock-ups made from CuCrZr alloys have exceeded those obtained earlier with CuAl25 alloys. [Copyright &y& Elsevier]

Currently, there is still no explicit design approach for cold-formed stainless steel columns with equal-leg angle sections in Europe. A comprehensive numerical investigation, validated by the available experiments collected in the literature, has therefore been undertaken to provide benchmark data for the assessment of design procedures for cold-formed stainless steel angle columns currently adopted in European and Australian codes. Minor-axis flexural buckling, as well as flexural-torsional buckling have been considered. In total, 27 different cross-section sizes covering both slender and non-slender sections, and a wide range of column slenderness values have been examined including austenitic, duplex and ferritic grades. On the basis of the experimental and numerical results, new design recommendations for cold-formed stainless steel equal-leg angle columns have been made per family of stainless steel. The suitability of the proposals was confirmed by means of a reliability analysis. • FE parametric studies including geometric and material nonlinearity performed. • Accuracy of European and Australian codified procedures assessed. • Proposal provided for different buckling curves per stainless steel family. • Reliability analysis of existing and proposed design recommendations carried out. [ABSTRACT FROM AUTHOR]

The article presents the winners of the 2006 Bodycote International Prize Paper Competition. The competition attracted entries from students across the UK, continental Europe and the USA. The first prize winners are M. Esfandiari and H. Dong, for their papers concerning plasma surface engineering of precipitation hardening stainless steels. Y. N. Kok, J. G. Wen, I. Petrov and P. Eh. Hovsepian combined their efforts to win the joint second prize for their papers concerning ion bombardment.

GEA Filtration claims that it is now working more closely with Graver Technologies in the European market place, by choosing Graver''s Scepter module as the preferred stainless steel cross-flow microfiltration (MF) membrane module for use in it systems. [Copyright &y& Elsevier]