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Showing 1 to 20 of 71 for “"Plastic flow"”.
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Plastic flow of single-crystal olivine.
Thesis. 1975. Ph.D. cn--Massachusetts Institute of Technology. Dept. of Earth and Planetary Sciences.
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Kinetics of Plastic Flow in Polycrystal Plasticity
An elasto-viscoplastic polycrystal plasticity model is developed that considers the kinetics of plastic flow. Strain rate and temperature dependencies, included in the single crystal constitutive response, are based on the isotropic mechanical threshold stress continuum model. A modified power law …
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The early stages of plastic flow in copper
Thesis (Sc. D.)--Massachusetts Institute of Technology. Dept. of Mechanical Engineering, 1967.
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A study of the law of plastic flow of metals
… the strain theory as proposed by St. Venant. Plastic material: 1. The plastic (or converted) strain theory with m = 2 is the correct combined stress relation for plastic materials. 2. The true stress-strain diagram or true stress-true elongation (reduction of area) diagram should be used. …
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A Numerical Procedure for the Analysis of Contained Plastic Flow Problems
Made available in DSpace on 2014-12-05T17:37:42Z (GMT). No. of bitstreams: 1 6402895.pdf: 3301306 bytes, checksum: cd9c6852b9bd3bf7bbb2f79ad4c0f740 (MD5) Previous issue date: 1963
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Compressive Strength, plastic Flow Properties, and Surface Frictional Effects of 1100, 3003 and 6061 Aluminum Alloys
Made available in DSpace on 2017-07-06T18:55:52Z (GMT). No. of bitstreams: 3 Pinkerton_Gary_W_MS.pdf: 82796141 bytes, checksum: c260c320cdaa91996ec47c9278f4a119 (MD5) Pinkerton_Gary_W_MS_ABS.pdf: 1017267 bytes, checksum: 553bca216fec89af57e94d852d9e877c (MD5) license.txt: 4813 bytes, checksum: …
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Lattice Relaxation by Plastic Flow and Study of Apparent Critical Layer Thickness in II-VI/GaAs(001) Heterostructures
… a generalized model for lattice relaxation by plastic flow in semiconductor heterostructures. It is applicable to graded and multilayered structures, allows for changes of temperature or growth rate, and accounts for differential thermal expansion. For the implementation of this model we …
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A microtexture based analysis of surface roughening in ductile metals during tensile deformation
… mechanisms of surface roughening are based on plasticity analysis of the actual material data. Both the microstructural characterisation and the texture determination was carried out using mainly electron microscopy techniques. Electron backscattered diffraction techniques were used to measure …
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A microtexture based analysis of surface roughening in ductile metals during tensile deformation
… mechanisms of surface roughening are based on plasticity analysis of the actual material data. Both the microstructural characterisation and the texture determination was carried out using mainly electron microscopy techniques. Electron backscattered diffraction techniques were used to measure …
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Mechanisms of plastic deformation in amorphous silicon by atomistic simulation using the Stillinger-Weber potential
… liquidlike. The mechanical behavior of a-Si when plastically deformed to large strain can be completely described by the mass fraction [phi] of liquidlike material in it. Specifically, samples with higher [phi] are more amenable to plastic flow, indicating that liquidlike atomic environments act …
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Numerical Analysis of the Effects of Void Growth and Crack Tip Opening on Ductile Fracture
… particles which nucleate microscopic voids. Plastic flow in the metal allows the voids to grow and link up to create larger flaws such as cracks. In previous research, the basic mechanics of ductile fracture has been examined using two-dimensional models. However, some problems in ductile …
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Numerical Analysis of Stable Crack Growth in Elastic-Plastic Materials in Small Scale and General Yielding
Stable crack growth problems in elastic-plastic materials are investigated with the aid of the finite element method. The formulation used for steady state crack growth under small scale yielding conditions has the feature that the finite element mesh convects along with the moving crack tip. …
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An Assessment of in-Service Stress Relaxation of a Work-Hardened Aluminum-Magnesium Alloy
… the special phenomenological expression in the plastic element, the Hart's type models are not suitable for simulating the deformation with bulk plastic flow. In order to predict the typical industrial forming and in-service response of sheet metal, such as sheet metal forming and subsequent …
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Calculation of Notch Strains Under Multiaxial Nominal Loading
… at stress concentrators in structures of elastic-plastic, isotropic material subjected to proportional and nonproportional multiaxial nominal loading. The method uses anisotropic plasticity theory to define a structural yield surface in nominal stress space that incorporates both the isotopic …
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The identification and modelling of the dominant failure mode in hot forging tooling
… dominant failure mode was associated with the plastic deformation of the tooling. Testing was performed to gather sufficient data to allow for the development of a lifing model. Isothermal tensile and fatigue tests were performed under temperatures and strain rates representative of hot forging …
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Constitutive equations for granular materials : application to dry sand and powder metal
… model is formulated for describing the plastic flow of cohesionless granular materials. This constitutive model has been implemented in the finite element package ABAQUS/explicit(1999) and is used to predict the strain localization in geomaterials. The numerical calculations are shown to …
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Ductility in high chromium super-ferritic alloys
The competition between microfracture and plastic flow has been studied in relation to the thermomechanical processing parameters and minor element chemistry of wrought super-ferritic alloys based on a composition of Fe-40wt% Cr. These alloys have been developed for corrosion-resistant …
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Wear and friction studies of alumina: Correlation with electron triboemission
… micrographs by different relative proportions of plastic flow material and fractured surface in the wear scar. In all but one wear regime, the correlation between the wear volume and cumulative triboemission is modest (linear regression coefficient R2 = 0.71); including the one atypical wear …
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The relationship between texture and formability in sheet metals
… An experimental assessment of the anisotropy of plastic flow was made by means of both Knoop hardness measurements and tensile and plane-strain compression tests. From the latter, formability and hardening parameters were obtained and compared with the predicted behaviour. The earing behaviour of …
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