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A series of TiZrNb(V) high entropy alloy-based metallic coatings have been deposited using high-power impulse magnetron sputtering (HiPIMS), with variable V concentrations and constant ratios among the other metals. The coatings were analyzed regarding their composition, surface and cross-sectional morphologies, microstructure, roughness, mechanical properties, oxidation resistance, and thermal stability. The structure of the deposited coatings reveals a transition from the bcc crystal structure to an amorphous phase as the V concentration increases. The addition of V also led to a decrease in roughness Ra and an improvement in adhesion, while it did not affect hardness, which remained at ∼10–11 GPa for all samples. Annealing under a protective atmosphere at 400 °C caused structural ordering, which was followed by an increase in mechanical properties. The purpose of the present paper is, therefore, to present a study on the deposition of TiZrNb coatings with increasing V concentration prepared by HiPIMS and to understand the role of V concentration on their structure, chemical composition, mechanical properties, and oxidation resistance. Comparison of the results with those achieved for a reference TiZrNb coating is presented too. [ABSTRACT FROM AUTHOR]

A UK National Thermal-Hydraulics Facility (NTHF) dedicated to supporting new reactor and other relevant business is being developed, one of the purposes being to deliver on the government’s carbon emission reduction commitments. The facility site is foreseen to be at Menai Science Park on the isle of Anglesey in North Wales, a region expected to see significant low carbon energy deployment in coming years. The UK NTHF is envisioned to cater for the needs of emerging nuclear in the UK – but also to serve as a hardware platform for international thermal-hydraulics research collaboration. Plans are to construct a platform capable of maintaining several test loops including support for the UK’s on-going, conventional nuclear new build programme as well as Gen-IV systems and associated materials like molten salt and liquid metal coolant media. Motivations are given for NTHF expected capabilities and requirements, which form the basis for its current design and planning state.

* The UK's 2050 net zero target will require deep decarbonisation of all areas of the economy which provides tremendous opportunities for nuclear technology. * The smelting and re-melting of metals accounts for a considerable portion of the world 's primary energy consumption and is responsible for almost 30% of industrial CO2 emissions. Nuclear power and hydrogen could play a key role in reducing this. * Here the history of nuclear metal production in the UK is presented using case studies including the "atomic" smelters of the 1960s and the efforts of the European Nuclear Steelmaking Club. The precedent set by these programmes provides useful lessons that should guide the future application of nuclear technology to metal production. [ABSTRACT FROM AUTHOR]

Sintered (1475 °C/2 h) pellets of Ba(Zn[sub 1/3]Ta[sub 2/3])O[sub 3] were annealed at temperatures ranging from 1550 to 1625 °C/15 h and subsequently quenched into water. The degree of B-site order between the Zn and Ta cations was investigated using x-ray diffraction (XRD) and transmission electron microscopy (TEM). Samples quenched from 1575 to 1600 °C exhibit the highest degree of order by XRD. Dark-field TEM images from these samples revealed 1:2, Zn:Ta, trigonal, ordered domains approximately 0.4 μm diam near grain boundaries but 100 nm in the grain interior. Samples annealed and quenched from 1625 °C exhibited no ordered superlattice reflections by XRD. However, diffuse scatter along <111> directions and fcc rather than trigonal ordered reflections were observed in electron diffraction patterns. Disordered samples were subsequently annealed at 1500 °C/15 h (below the order-disorder phase transition ∼1625 °C) and ±[FRACTION SHAPE="CASE"][NUM]1[/NUM][DEN]3[/DEN][/FRACTION]{hkl} superlattice reflections reappeared in XRD patterns demonstrating the reversibility of the phase transition. © 2000 American Institute of Physics. [ABSTRACT FROM AUTHOR]

Presents a study which examined the transmission electron microscopy of proton-exchanged LiNbO[sub 3] waveguide channels. Intensity of diffusion within the single-srystal electron diffraction patterns; Experimentations; Results.