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Showing 1 to 20 of 89 for “"nickel-based"”.
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Recrystallisation in Single Crystal Nickel-Based Superalloys
… during investment casting of single crystal Ni-based superalloys arise from differences in thermal contraction between the metal and ceramic mould-and-core. If deformation is above a critical limit, subsequent solution heat treatment of the alloy causes recrystallisation. Crack nucleation and …
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Simulation of creep in nickel based single crystal superalloys
Nickel based single crystal Superalloys are finding wide spread use in high temperature gas turbines and other similar applications because of their superior high-temperature strength and creep properties as compared to the other materials. This is due to two factors: solid solution and …
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Influence of surface hardening on single crystal nickel-based superalloys
… (DCR), on the microstructures of single crystal nickel-based superalloys. These alloys have excellent high temperature properties, and consist of a randomly substituted face centred cubic matrix phase known as γ, together with a large volume fraction of an ordered precipitate phase, most often …
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Transient Liquid Phase Bonding of Titanium-, Iron- and Nickel- Based Alloys
<p>The operating temperature of land-based gas turbines and jet engines are ever-increasing to increase the efficiency, decrease the emissions and minimize the cost. Within the engines, complex-shaped parts experience extreme temperature, fatigue and corrosion conditions. Ti-based, Ni-based and …
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The microstructure and properties of powder HIPped nickel-based superalloy CM247LC
The response of powder of the Nickel-based superalloy CM247LC to a range of Hot Isostatic Pressing (HIPping) conditions and post-HIP heat treatments has been investigated as a preliminary step in the assessment of net shape HIPping as a possible process-route for component production. A HIPping …
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Net-shape hot isostatic pressing of a nickel-based powder superalloy
Microstructural analysis and mechanical property assessment have been carried out on hot isostatically pressed (HIPped) and heat treated samples of RR 1000 powder to assess Net Shape HIPping as a process-route for aero engine components. HIPping led to (Hf,Zr)-rich oxides and carbides on prior …
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Understanding surface and sub-surface phenomena in nickel-based superalloy castings
Nickel-based superalloys are high-temperature materials, created to operate in the aggressive conditions found within gas turbine engines. Single crystal turbine blades are investment cast, followed by a complex series of operations including heat treatment, machining, blasting, etching and …
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Factors contributing to the yield strength of polycrystalline nickel-based superalloys
Nickel-based superalloys are the material of choice for use in the hottest regions of gas turbine engines due to their inimitable mechanical properties, in particular, high temperature strength. As we become increasingly aware of the environmental consequences of air travel, manufacturers are …
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Comprehensive Characterization of Nickel-Based Metallic Foams and Their Applications as Electrocatalyst Materials
This contribution explores the applicability of nickel-based metallic foams as active electrodes and as electrocatalyst support materials. A comprehensive characterization of Ni and multi-component Ni-based foams is presented and includes the analysis of their structural, chemical, and …
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Research and development of nickel based catalysts for carbon dioxide reforming of methane
… is primarily focused on the development of novel nickel-based catalysts to achieve stable operation for CO2 reforming of CH4. Following Dowden’s strategy of catalyst design, a series of nickel-based catalysts are designed with a general formula: Ni-Me/AlMgOx (Me = Co, Cu, Fe, or Mn). The designed …
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Grain boundaries and creep deformation mechanisms in a high performance nickel-based superalloy
… the new Rolls-Royce Alloy 12-1 polycrystalline nickel-based superalloy for disc application in gas turbine engines. In particular, this study aims to progress the understanding of the effect of grain boundaries in relation to the content of minor additions such as C, B and Zr. This was achieved …
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Wear of Polycrystalline Cubic Boron Nitride Cutting Tools when Machining Nickel-based Superalloys
… rates are observed when using PcBN to machine Ni-based superalloys - in particular Inconel 718. While there have been other studies on the machining of this alloy using PcBN tools, and the types of wear that occur have been described, the underlying mechanisms are still not well understood. With a …
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Carbide formation in a nickel-based superalloy during electron beam solid freeform fabrication
… for the manufacture and safe use of certain nickel-base superalloy parts, notably turbine disks. The growth of carbide particles from the liquid during EBSFF processing of Alloy 718 has been modeled assuming diffusion control and isolated spherical carbides. The driving force for growth is …
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Microstructural evolution and mechanical behavior in nickel based alloys for very high temperature reactor
… 230), which are difficult to detect using lab-based X-ray machines or neutron scattering facilities, were successfully examined using high-energy X-ray diffraction. The loading processes of the austenitic matrix and the carbide were separately studied by analyzing their different lattice strain …
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A Biomechanical Study of Gold and Nickel-Based Dental Bridge Systems Utilizing Distal Abutment Dental Implants.
It is estimated there are over thirty million edentulous people in the United States alone. In this population the use of conventional treatment modalities, i.e., full or partial removable dentures, has been demonstrated to result in: (1) loss of alveolar bone height with subsequent inability to …
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