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Showing 1 to 11 of 11 for “"Slip band"”.
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Characterization of silicon photovoltaic wafers using polarized infrared imaging
… with the thermal residual stress, forming slip band structures oriented at 45 degrees to the wafer edges. The measured PE images are then interpreted using a discrete dislocation-based numerical modeling approach that accounts for stress relaxation in the wafer due to the dislocation …
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Some aspects of crack initiation in mild steel subjected to fatigue stressing in a corrosive environment
… studies indicate that a sulphur enriched band of ferrite exists around the non-metallic inclusions and corrosion occurs in this contaminated band with and without applied stress. Cyclic stress enhances the formation and coalescence of micropits at and around the inclusions leading to the …
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On the plastic deformation behaviour of nickel-based superalloys: low cycle fatigue and stress orientation effects
… with the motivation of understanding how slip bands form and develop prior to crack initiation. Electron microscopy techniques are used in alloy RR1000 to characterise these dislocation structures at different length scales in interrupted tests at room temperature and 700°C. The true slip …
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Fatigue Modeling of U720 --- a Multi-Scale Approach in Understanding Grain Boundary Effects on Crack Initiation
… approach is to model the energy of a persistent slip band (PSB) structure and use its stability with respect to dislocation motion as our failure criterion for crack initiation. The components that contribute to the energy of the PSB are identified, namely, the stress field resulting from the …
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A multiscale study on the origins of the Portevin-Le Chatelier effect in polycrystalline nickel-based superalloys
… of localised strain within so-called Lüders bands. Wide similarities between the behaviour of the superalloy and the binary alloy suggest that the microstructural complexity of the superalloy is not necessary to explain the effect. The presence of history dependent effects upon a change in …
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The Role of Slip System Activation on Ni-Based Superalloy High Temperature Fatigue
… be caused by the activation of the {100} cubic slip plane along the usual {111} octahedral slip plane. This study continued the work of previous research by using SEM and EBSD imaging to characterize the microstructure of IN-718 specimens before and after preconditioning. The microstructure …
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Fatigue modeling of U720 – A multi-scale approach in understanding grain boundary effects on crack initiation
… are used to obtain the energy barriers for slip nucleation and transmission across various GB characters, which are used to service our fatigue model. In this study, we construct a model for prediction of fatigue crack initiation based on the material’s microstructure. Our approach is to …
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Dislocations and Green's functions in prestressed solids
… activation of dislocation clustering along slip band directions. Several of the presented results remain valid within a three-dimensional context. Novel infinite-body three-dimensional Green's functions are derived for the incremental deformation of an incompressible, anisotropic, …
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Fatigue mechanisms in FV520B, a turbine blade steel.
… condition, multiple site nucleation due to slip band cracking was the prevalent mechanism especially at higher nominal stress amplitudes. The tolerance of this high strength material to small defects at higher stress levels and the actual size of the critical microstructural defects …
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Quantitative understanding of the role of grain boundaries in polycrystalline deformation via multiscale digital image correlation
… Particularly we address the interaction of slip with GBs which can result in slip blockage or slip transmission and investigate how these two possible outcomes of slip-GB interaction influence the plastic strain magnitudes and fatigue crack formation in GB regions. In the first part of this …
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Flow Localization Effects of Austenitic Stainless Steel after Exposure to Irradiation Environments
Made available in DSpace on 2017-07-06T18:59:33Z (GMT). No. of bitstreams: 3 Wu_Xianglin_MS.pdf: 30674957 bytes, checksum: d466a380d68cb177e3ec4ddab2ff6d4b (MD5) Wu_Xianglin_MS_ABS.pdf: 629001 bytes, checksum: 49cb4eea28d7bb2b1f28089eb82d2795 (MD5) license.txt: 4813 bytes, checksum: …