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Showing 1 to 15 of 15 for “"Cubic Boron Nitride"”.
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Ion-induced stress relaxation during the growth of cubic boron nitride thin films
The aim of the presented work was to deposit cubic boron nitride thin films by magnetron sputtering under simultaneous stress relaxation by ion implantation. An in situ instrument based on laser deflectometry on cantilever structures and in situ ellipsometry, was used for in situ stress …
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Wear of Polycrystalline Cubic Boron Nitride Cutting Tools when Machining Nickel-based Superalloys
Cubic boron nitride is the second hardest material known, after diamond. Polycrystalline cubic boron nitride, PcBN, is a composite consisting of cubic boron nitride grains and either a metallic or ceramic binder phase. It is currently used as a cutting tool material for several difficult to machine …
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The application of the soft impression technique to evaluate flow stress, creep and frictional deformation of polycrystalline diamond and cubic boron nitride
… the flow stress of polycrystalline diamond and cubic boron nitride as a function of temperature and a mathematical model has been proposed to estimate the flow stress in isotropic polycrystalline materials. This model was first analysed by Love (1928) and was used as the basis on which to …
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Characterization of Boron Nitride Thin Films on Silicon (100) Wafer.
Cubic boron nitride (cBN) thin films offer attractive mechanical and electrical properties. The synthesis of cBN films have been deposited using both physical and chemical vapor deposition methods, which generate internal residual, stresses that result in delamination of the film from substrates. …
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Characterizing the potential energy surface of two dimensional and bulk materials using high dimensional neural network potentials
… bulk silica, graphene, diamond, hexagonal boron nitride, and cubic boron nitride. Here, a general mapping from atomic coordinates to the potential energy surface is obtained using a feed-forward artificial neural network. An approximate Density Functional Theory method, Density Functional …
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Methods and Applications for Nanometrology using Scanning Precession Electron Diffraction
… under a nano-indent in the ultra-hard material cubic boron nitride, illustrating the well-suitedness of scanning electron diffraction to the investigation of such highly deformed materials. Our findings indicated that a lobe like orientation pattern is formed, similar to that seen by other …
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The effects of properties, microstructure and phase transformation on the erosion of hard materials
… sizes of alumina, stabilised zirconias, sialon, cubic boron nitride and polycrystalline diamond, and these have a range of microstructural, physical and mechanical properties. The damage modes are described for the two types of erosion and the results are critically discussed. It has been shown …
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The performance of ultra-hard cutting tool materials in maching aerospace alloy TA48
… has been made of the respective performance of cubic boron nitride (CBN) and polycrystalline diamond (PCD) cutting tool materials and compared to various coated and uncoated tungsten carbide grades when cutting titanium alloy workpieces. Two important experimental techniques were employed during …
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Characterizing the Frictional Interface in Friction Stir Welding
… of the frictional modes for the polycrystalline cubic boron nitride (PCBN) tool and 1018 steel work piece interface as functions of temperature, velocity, and normal force. Two linear models were chosen. A statistical method called membership function regression was used to determine the …
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The electronic and mechanical properties of the XYB14 complex borides studied by first-principles methods
… to chemical corrosion. Alternatively, boron compounds are promising candidates because of boron's hardness and excellent chemical and thermal stability.</p> <p>Conventional superhard materials, such as diamond and cubic boron nitride, are usually comprised of a strong, covalently bonded …
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Synthesis of Ti₂AlC, Ti₃AlC₂ and Ti₃SiC₂ MAX phase ceramics; and their composites with c-BN
… yet also heat-tolerant, strong and lightweight. Cubic boron nitride (c-BN) is a widely used abrasive in grinding wheels, which is exceeded in hardness only by diamond. Composites of c-BN and selected MAX phases may result in materials of some interesting and useful properties for application in …
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Engineering Rare-Earth Based Color Centers in Wide Bandgap Semiconductors for Quantum and Nanoscale Applications
… wide bandgap semiconductors, such as hexagonal boron nitride and tungsten disulfide, offer for device integration. First, confocal Raman and fluorescence spectroscopy techniques are combined to isolate single native color centers in cubic boron nitride nanocrystals that feature room-temperature …
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Ni-Al-Ta alloys for high temperature abrasive coatings
… systems for high-temperature use are composed of cubic boron nitride (cBN) abrasive particles embedded in a NiCoCrAlY anchor phase. Previous work has shown that at the operating temperatures achieved in the high-pressure turbine, the NiCoCrAlY is unable to retain the embedded cBN particles under …
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Impact of morphology and confinement effects on the properties of aligned nanofiber architectures
… such as diamond (~/~ 7:8 GPa x (g/cm3)-2) and cubic boron nitride (~/~ 5:2 GPa x (g/cm3)-2). Using the structure-property prediction tools developed in this thesis, precise tailoring and prediction of application-specific performance of aligned NF based architectures is enabled, and specific …
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Development of meso-scale flexible cutting tool for micro-groove cutting in steel
One of the key challenges in product miniaturization technologies is the creation of micro-grooves in devices for mechanical, electronic, photonic and bio-medical applications, such as production of hot embossing molds, micro-heat exchangers, optical lithography masks, micro-forming dies, …