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Showing 1 to 20 of 22 for “"nickel-based superalloy"”.
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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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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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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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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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Nickel-based superalloy operating temperature determination via analysis of gamma/gamma' microstructure and coating/base material interdiffusion
The average operating temperature of RENÉ N5® high pressure turbine blades was evaluated via [gamma]/[gamma]' microstructure and coating/base metal interdiffusion methods. The [gamma]' volume fraction was measured by point counting and direct area measurement. The data, however, were found …
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A study of Laser weldability of IN-738 Nickel-based Superalloy in a new pre-weld heat treatment condition
… heat treatment was developed recently for IN 738 superalloy. Therefore, the research described in this master’s thesis was to study the laser weldability improvement of the alloy which had undergone the new heat treatment, FUMT and the results were compared to an existing pre-weld heat treatment, …
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The effect of the build orientation and heat treatment on the fatigue and fracture properties of a directed energy deposited nickel-based superalloy (Inconel 718)
… rate and fracture toughness properties of the nickel-based superalloy, Inconel 718 that has been manufactured by additive manufacturing technique, directed energy deposition (DED). Three different build orientations namely XY, XZ and ZX, in both the as-built and heat-treated conditions were …
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A Study of Reduced Chromium Content in A Nickel-Base Superalloy via Element Substitution and Rapid Solidification Processing
A study of reduced chromium content in a nickel-base superalloy via element substitution and rapid solidification processing was performed. The base alloy studied was a commercial nickel-based superalloy, 713LC, which was developed by the INCO family of companies. The two elements used as partial …
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Efeito de múltiplos ciclos de solubilização sub-solvus delta e envelhecimento na microestrutura e propriedades mecânicas da superliga 718
The nickel based superalloy 718 was developed to meet the requisites of components for aircraft engines, due to its excellent creep resistance up to 650°C. During the maintenance of the engines, the components can be submitted to successive repair procedures, however the mechanical properties can …
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The identification and modelling of the dominant failure mode in hot forging tooling
… hot forging tooling, used in the production of nickel based superalloy compressor blades. A preliminary study identified the most frequently occurring part defects that cause tool failure. The forming process was characterised, relevant tooling failure modes were identified and the mechanical …
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Real-Time Thermography for In Operando Additive Manufacturing Defect Mitigation using a Machine Learning Approach
… on the surfaces of maraging steel (M300) and Nickel-based Superalloy (In718) constructs and its correlation with process parameters. Post processed thermal image datasets were utilized to train a supervised machine learning model (Multi-Layer Perceptron) for defect prediction, while …
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The effect of bond coat oxidation on the microstructure and endurance of two thermal barrier coating systems
… barrier coating systems consisting of a CMSX-4 nickel-based superalloy substrate, NiCoCrAlY overlay bond coat applied by two different techniques and a yttria stabilised zirconia topcoat applied by electron beam physical vapour deposition (EBPVD). The bond coats were applied by either high …
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Relating fatigue crack growth to microstructure via multiscale digital image correlation
… The first part of this work introduces two DIC-based techniques for measuring fatigue crack closure levels and demonstrates them on titanium. At the macroscale, a least squares regression was performed on full field measurements of displacement near the crack tip. At the microscale, two-point …
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Fatigue modeling of U720 – A multi-scale approach in understanding grain boundary effects on crack initiation
… scatter is observed in the fatigue response of a nickel-based superalloy, Udimet 720. This scatter can be partly attributed to the variability in the microstructure of this material. Hence, there is great interest in linking the microstructure to fatigue properties using a multi-scale approach …
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Deposition of yttria-stabilized zirconia thermal barrier coatings by laser-assisted plasma coating at atmospheric pressure
… be applied on silicon wafers, and multi-layer nickel-based superalloy substrates (René N5), by a new deposition technique called laser-assisted plasma coating at atmospheric pressure (LAPCAP). The plasma generated in the APPT has the potential to increase the vapor volume ablated from the YSZ …
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Exposure and Characterization of Candidate Materials for Use in Supercritical Water Reactors
… corrosion rate. Austenitic stainless steels and nickel based superalloys are candidate materials for the structural components of energy generation that makes use of supercritical water, owing to the high strength and corrosion resistance required for operation under these conditions. The …
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Investigation of thermal effects on fatigue crack closure using multiscale digital image correlation experiments
… on fatigue crack closure of Hastelloy X, a nickel-based superalloy. Using multiscale, digital image correlation (DIC), macroscale experiments were performed at 2x magnification (2 µm/pix), providing full-field crack closure measurements. Microscale experiments performed at 10x magnification …
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A multiscale study on the origins of the Portevin-Le Chatelier effect in polycrystalline nickel-based superalloys
… Chatelier (PLC) effect. This includes nickel-based superalloys, between approximately 200 °C and 600 °C. The PLC effect is widely attributed to Dynamic Strain Ageing (DSA), referring to dislocation pinning effects caused by the diffusion of solute to dislocations, driven by elastic …
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Advanced experimental measurements of heterogeneous strain and temperature change in metals
… elevated temperature deformation in the nickel-based superalloy Haynes 230 and elastocaloric cooling in shape memory alloys. Three loading conditions were examined in the elevated temperature portion: fatigue crack growth, creep, and tension. Measurements were made on varying length …
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