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Showing 1 to 20 of 20 for “"borides"”.
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The Structure of Selected Rhombohedral Borides
Made available in DSpace on 2014-12-12T00:32:34Z (GMT). No. of bitstreams: 1 7310015.pdf: 3395933 bytes, checksum: f6c7daf4c5c32eb576a077feb56755d9 (MD5) Previous issue date: 1972
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Optimization of High Entropy Borides for Advanced Applications
… (UHTC) materials, based on transition metal borides and carbides, which are characterised by several advantageous physico-chemical properties, such as elevated melting temperatures, chemical inertness, good thermal and electrical conductivities, etc. In addition, UHTCs are also known to …
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Growth kinetics and microstructure in two precursor chemical vapor deposition of borides
Submission published under a 24 month embargo labeled 'U of I Access', the embargo will last until 2024-12-01
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Synthesis and oxidation behavior of Cr alloyed uranium borides at high temperatures
… behavior, and oxidation behavior of uranium borides and chromium- and yttrium- alloyed uranium borides are investigated. The structure of the synthesized uranium borides and chromium- and yttrium- alloyed uranium borides were probed using synchrotron X- ray Powder Diffraction (XRD) and Pair …
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The electronic and mechanical properties of the XYB14 complex borides studied by first-principles methods
… "by design".</p> <p>Recently, a class of complex borides, based upon the AlMgB14 crystal structure, has been proposed as a potentially superhard material. Unlike conventional superhard materials, the crystal structure of AlMgB14 is only loosely packed. It is also known that a variety of metal …
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Evaluation of metal nitrides and borides as alternative electrocatalyst support materials for polymer electrolyte fuel cells
… to carbon. In this study, metal nitrides and borides (TiN, ZrN, TiB₂ , ZrB₂ and LaB₆) were evaluated as potential support materials, in an attempt to improve the durability and performance of PEFCs.
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Thermochemical modeling and chemical vapor deposition of two-phase borides in the Hf-Si-B-Cl-H system
… found to deposit in the Hf-B-Cl-H system. Both borides coatings exhibited several different surface morphologies. The separate delivery of BCI₃ and SiCl₄, while necessary to prevent their gas phase reaction, caused reactant concentration gradients at the substrate surface due to poor mixing. …
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Grain boundaries and creep deformation mechanisms in a high performance nickel-based superalloy
… and tetragonal M<sub>3</sub>B<sub>2</sub> borides. Grain boundaries showed a serrated character with large γˈ particles and fine tetragonal M<sub>5</sub>B<sub>3</sub> precipitates before creep testing. Analysis after creep testing revealed a progressive evolution of grain boundary …
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The Formation and Reactivity of BORON CARBIDE and related materials
… are discussed in relation to those of other borides and carbides. Information so far available on the sintering of this material is summarised in relation to its reactivity. Sintering into monolithic components can only be achieved by hot pressing at pressures between 200 and 300 Kgcm-2 and …
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Rhenium, osmium and iridium diborides by mechanochemistry: Synthesis, structure, thermal stability and mechanical properties
Borides are implemented in a range of industrial applications due to their unique mechanical, electrical, thermal and catalytic properties. In particular, transition metal diborides are of special interest. In the recent years, borides of rhenium (Re), osmium (Os) and iridium (Ir) have been studied …
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Single-crystal X-ray diffraction at extreme conditions in mineral physics and material sciences
… on the examples of studies of transition metal borides, a metal-doped boron phase, silicates, and oxides. Particularly, we solved and refined crystal structures of Co5B16, MnB4, Al-doped β-boron, knorringite, and Fe3+-bearing bridgmanite, investigated the high-pressure behaviour of FeB4, Fe2B7, …
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Boron induced surface modification of transition metals
… into the metal substrate and form hard metallic borides. As a result of boronizing, several properties such as hardness, wear resistance, corrosion resistance, and high temperature oxidation resistance improve which make the metal substrate more suitable for industrial applications. These …
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Investigation of "conventional" superconductivity in ternary cerium compounds through high pressure studies
… in the cerium-containing ternary borides and silicides: CeRu(,3)B(,2), CeOs(,3)B(,2), and CeRu(,3)Si(,2). These are the only ternary cerium compounds where "conventional" (as opposed to heavy fermion) superconductivity has been observed to date;The closely related crystal …
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Multi-component boron coatings on low carbon steel AISI 1018
… formation of solid solution of transition-metal borides. The distortion of crystal lattice parameters generated microstrain in the boride phase. The Synchrotron microdiffraction confirmed the presence of about 5-10 microns of transition-metal boride phase at the surface. Moreover, the additional …
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Processes and Materials for Space Exploration and Colonization
… work, new materials based on transition metal diborides are being synthesized, sintered and characterized according to innovative technologies, and their performance are being assessed in terms of mechanical properties and oxidation resistance. Research is focused on multicomponent transition …
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Atomistic modelling of precipitation in Ni-base superalloys
… content and other constituents such as carbides, borides, oxides and topologically close packed phases. In this work we have set out to investigate the onset of $\gamma^{\prime}$ ordering in Ni-Al single crystals and in Ni-Al bicrystals containing coincidence site lattice grain boundaries (GBs) …
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The 5-th element. A new high pressure high temperature allotrope
… Experimental products were free from any borides only when Au was used. The maximal length of synthesized B28 crystals was ~100 µm and after their isolation high quality X-ray diffraction data was obtained. Synthesized single crystals of the orthorhombic high-pressure boron phase were …
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Stability of nickel-base superalloys for turbine disc applications
… as MC and M$_{23}$C$_6$ carbides and M$_3$B$_2$ borides.
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JOINING OF ULTRA-HIGH TEMPERATURE CERAMICS TO THE SAME AND REFRACTORY METALS VIA FUSION WELDING
<p>"This research focuses on the joining of ultra-high temperature ceramics to either themselves or refractory metals/alloys via fusion welding and the mechanical strength of produced joints. The ceramics studied consisted of compositions within a diboride-carbide-carbide ternary system while …