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Showing 1 to 15 of 15 for “"deformation twinning"”.
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Shear-induced homogeneous deformation twinning in FCC aluminum and copper via automistic simulation
… during shear, although the extent of plastic deformation before failure is over-predicted. In aluminum, both the Mishin and Ercolessi potentials are used, with only the former able to capture the majority of the behavior exhibited in first principle calculations. Both potentials are shown to …
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Defect mediated plasticity in Cu/Ag nanoscale multilayered metal composites: deformation twinning and wavy interface formation
Made available in DSpace on 2013-08-22T16:35:38Z (GMT). No. of bitstreams: 4 Ruizhi_Li.pdf: 2616507 bytes, checksum: dff899bcd8bac69b54dbea75d994edac (MD5) 0_Li_Ruizhi.docx: 28848935 bytes, checksum: 4c460173b168128b9fb90f0828607c49 (MD5) Li_Ruizhi.docx: 28848935 bytes, checksum: …
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The Role of Twinning in the Plastic Deformation of Alpha Phase Titanium
… In particular, a better understanding of how deformation twinning interacts with microstructural features in titanium alloys is required, because such twinning facilitates plastic deformation at a higher strain rate than dislocations. To investigate this behaviour, commercial purity titanium …
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Investigating the Effect of Austenite Grain Size and Grain Boundary Character on Deformation Twinning Behavior in A High-Manganese TWIP Steel: A TEM In-Situ Deformation Study
… but generally poor ductility during deformation regardless of their crystal structure which is often called the strengthductility trade-off relationship and generally appears in most ultrafine-grained metals. The ultrafine-grained (UFG) high manganese austenitic twinning-induced …
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Energetics Calculation of {10-12} Twin Nucleation and Growth in Magnesium and Alloys using Density Functional Theory and Atomistic Simulation
Deformation twinning strongly affects the mechanical properties of magnesium (Mg) and its alloys, as well as other alloys with hexagonal close-packed (HCP) structures. The influence of solute atoms such as aluminum (Al), zinc (Zn), and yttrium (Y) on {"10" "1" ̅"2" } twin nucleation and growth in …
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Multiscale Experimental Study on the Effect of Texture and Anisotropy on the Thermomechanical Response of Zirconium
… a possible dependence of dissipation on deformation mechanism. No correlation is found between deformation twinning and energy dissipation, and the appearance of energy storage in basal textured polycrystals is explained by the presence of localized deformation. Experimental and numerical …
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Atomistics of defect nucleation and mobility : dislocations and twinning
… defects of interest being dislocations and deformation twinning, and emphasis on the atomistic mechanisms and measures. The contributions presented in the thesis may be regarded as advances in both methods development and mechanistic understanding of dislocation mobility and twinning …
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Three Dimensional Characterization of Deformation Twins Using Synchrotron X-Ray Diffraction
… titanium in aerospace industry. Understanding deformation mechanisms of HCP metals is crucial for developing predictive models that can be used for performance and failures analysis of engineering components. The two main deformation modes in HCP polycrystals are slip and twinning. While …
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The Effect of Co on the Deformation Response of Fe-Mn Alloys
… and exhibit several interesting responses to deformation which lead to the possibility of desirable mechanical properties for many engineering applications. The addition of other elements to the system further improves properties and can lead to interesting effects like transformation induced …
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Crystal-plastic deformation and chemical evolution of clinoamphibole
… undulose to patchy extinction and (100) deformation twinning surrounded by a mantle of recrystallized grains. In addition intragranular grains also occur within the cores. TEM analysis of the host grains revealed high densities of dislocations, dislocation arrays/subgrain boundaries …
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Deformation Behaviour of NiCo Multilayers with Modulated Microstructures
… study the influence of abrupt heterogeneities on deformation behaviour. While the deformation mechanisms of homogeneous coarse-grained and nanocrystalline materials are well documented, it is not clear from the current literature how these mechanisms may interact in a heterogeneous structure, and …
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Biomineralized structural materials with functional optical properties
… on a light scattering model. This armor utilizes deformation twinning and additional mechanisms at the nanoscale to enhance the energy dissipation efficiency by almost an order of magnitude relative to abiotic calcite. 3D quantitative analysis of the damage zone resulting from high load …
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Reassessing the Holleford impact structure: Applying modern techniques to a classic Canadian crater
… have hypothesized to be diagnostic of shock deformation at pressures between 12-17 GPa, were observed in one Holleford sample. Shock pressures for drill hole 2 were constrained to below 20 GPa, due to the absence of shock microstructures in zircon. These findings not only reinforce an impact …
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Modeling mechanical properties – linking atomistics to continuum
… and experiments is used to study the microscopic deformation mechanisms of materials. Atomic scale simulation tools include molecular dynamics and density functional theory. The experiments involve uniaxial tension and compression tests on: (a) single crystals of low stacking fault energy Co-33%Ni …
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Hot forging of the nickel-base superalloy ATI 718Plus
… changes due to recrystallisation and deformation occurring during forging. The body of work includes the testing and characterisation of 718Plus with and without $\eta$. High temperature compression tests were performed in the temperature range of 850 to 1025ºC, strains between 0.4 and …