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Showing 1 to 16 of 16 for “"Ni-based Superalloys"”.
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Understanding the Yield Behaviour of Single Crystal Ni-based Superalloys
Nickel-based superalloys are the material of choice for turbine applications due to their superior high-temperature strength capabilities. This has been attributed to the γ' precipitates which have the L1₂-ordered crystal structure. Because of the ordered crystal structure, dislocations must travel …
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Improving Oxidation Resistance in Polycrystalline Ni-based Superalloys for High-Temperature Applications
The design of new polycrystalline Ni-based superalloys with enhanced oxidation resistance can enable higher operating temperatures in aeroengines with increased fuel efficiencies and minimised CO₂ emissions. This thesis investigated the oxidation behaviour in polycrystalline Ni-based superalloys …
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Powder bed fusion of Ni-based superalloys: process optimization, heat treatments and mechanical performance
L'abstract è presente nell'allegato / the abstract is in the attachment
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Computer simulation of carburization corrosion of nickel-base superalloys
… was used to simulate the corrosion behavior of Ni-based superalloys in carburizing atmospheres. The model is based on Crank-Nicholson finite difference solution of the diffusion equation. The code also includes the ternary cross diffusion effect due to substitutional alloying elements that are …
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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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Compositional Optimisation of a Ni-based Superalloy for Additive Repair Applications
… manufacturing (AM) for the fabrication of Ni-based alloys has seen a massive uptake in commercial institutions. Among their many merits, AM techniques offer a unique route for the repair of a wide range of complex components. However, processing of the Ni-based superalloys used by the …
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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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Metallographic study of gamma - gamma prime structure in the Ni-based superalloy GTD111
The potential for land-based turbine buckets material rejuvenation presents a significant commercial and scientific interest. Ni-based superalloy GTD111 is used at a number of GE-manufactured power generation turbines. The outstanding creep resistance features of Ni-based superalloys can be …
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Novel integrated computational approach for designing Fe-Ni-based alloys
A novel computational approach for designing high temperature alloys is proposed; the approach incorporates properties prediction and optimisation. As for properties prediction, microstructural parameters, such as the volume fraction and precipitate size after heat treatment (replicating the …
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Untersuchungen der Strukturstabilität von Ni-(Fe)-Basislegierungen für Rotorwellen in Dampfturbinen mit Arbeitstemperaturen über 700 C
… for the components, which are thermo-mechanically loaded, only Ni-based superalloys are suitable for their fabrication, structure stability and thermo-mechanical characteristics. With view on creep and creep crack growth resistance as suitable candidates in the context a DFG research …
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Grain boundary engineering in additively manufactured polycrystalline materials
… produce complex near-net-shape components with minimal material waste. Grain boundary engineering (GBE) is a well-established approach for enhancing mechanical properties and reducing corrosion susceptibility in polycrystalline materials by increasing the fraction of low-energy grain boundaries. …
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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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Microstructural Evolution in Refractory Metal Multi-Component Alloy Systems
… temperatures than those tolerated by current Ni-based superalloys, motivating the search for alternative high temperature materials. Refractory superalloys based on AlTaTiZr and AlMoNbTaTiZr have attracted particular interest, as early studies indicate that the essential attributes for …
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Effect of systematic variation in Co:Ni ratio on elemental partitioning, lattice misfit and oxidation behaviour of γ'-strengthened (Ni,Co)75Al5Ti5Cr15 (at.%) alloys
Ni-based superalloys currently in-service as aero-engine turbine discs are operating at the limit of their high-temperature capability. Next-generation turbine disc superalloys must be capable of sustaining the higher operating temperatures (approaching 800°C) and stresses required for greater …
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Investigation of new synchrotron X-ray and neutron techniques for local crystallographic analysis of Ni-based single crystal superalloys
Nickel-based single crystal superalloys exploit a γ/γʹ microstructure, providing exceptional high- temperature strength and environmental stability, outperforming other known alloy systems. These properties make them useful for gas turbine applications. However, enhancing gas turbine efficiency …
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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 …