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Showing 1 to 20 of 186 for “"Stress state"”.
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Effects of stress state on fracture behavior of high carbon steel
Includes bibliographical references (pages 128-131).
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Studies of large volcanoes on the terrestrial planets : implications for stress state, tectonics, structural evolutions, and moat filling
Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Earth, Atmospheric, and Planetary Sciences, 1996.
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The Effects of Stress State, Material Properties and Environmental Conditions on The Propagation of Brittle Fractures in Mild Steel
Made available in DSpace on 2014-12-08T23:56:21Z (GMT). No. of bitstreams: 1 6507177.pdf: 4041839 bytes, checksum: fd5b57cd8d033a9f44129d326db31570 (MD5) Previous issue date: 1965
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Evaluation of stress state on the mechanical properties of 3D printed metallic lattice structures fabricated via laser powder bed fusion for orthopedic applications
… values to mimic bone, ideal for minimizing stress shielding. These benefits have caused a widespread proliferation of 3D printed porous metallic scaffolds in orthopedic implants, specifically Laser Powder Bed Fusion (LPBF). Once implanted, these devices experience complex stress states under …
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The Effect of Stress State and Precipitation on Stress-Induced Martensitic Transformations in Polycrystalline and Single Crystal Shape Memory Alloys: Experiments and Micro-Mechanical Modeling
To properly understand stress-induced transformations in aged NiTi single crystals, a micro-mechanical model is used to quantify the stress fields outside perfectly coherent Ti$\sb{11}$Ni$\sb{14}$ precipitates in NiTi. Using the model, the decrease in the orientation dependence of $\sigma\sb{\rm …
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The Ductile to Brittle Transition in Polycarbonate
… is used with a new cohesive zone model that is stress state and rate-dependent in order to simulate the ductile to brittle failure transition in polycarbonate. The cohesive zone model is motivated by experimental evidence that two different critical energies per unit area of crack growth exist …
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A simulation model for stress measurements in notched test specimens by x-ray diffraction
An analytical model was developed to simulate the stress state of notched tensile specimens. Actual experiments are being carried out by other investigators to study the relaxation of residual stresses in specimens containing stress raisers. In the present work, the stress state developed in …
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Random delamination of graphite/epoxy laminated composites : stress analysis, failure criteria, experimental characterization and stochastic modeling
… to determine the three-dimensional edge effect stresses around pin-loaded holes in symmetric laminated composites. The stress state around the holes is divided into two parts, one the in-plane stress state determined using the Classical Laminated Plate Theory (CLPT) and the other the boundary …
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Ductile fracture at intermediate stress triaxialities : experimental investigations and micro-mechanical modeling
… a comprehensive investigation into the effect of stress state on the onset of ductile fracture of an Advanced High Strength Steel (AHSS), covering development of new experimental procedures, material characterization and phenomenological as well as micro-mechanical modeling of the onset of …
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Determination of residual stresses in HSLA-100 steel weldments as a function of welding parameters using x-ray diffraction
… of various processing parameters on the residual stress state of HSLA-100 bead-on-plate weldments. Three groups of samples were provided to Virginia Tech by CDNSWC. The first (GPX) was a sample of unwelded, as-received base material; the second group (RS-) consisted of an experimental matrix of …
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Impact damage behaviour of lightweight materials
… The focus of this investigation is on the stress state and strain rate dependence of failure, and the effect of microstructural modifications on indentation and impact response. The thesis is divided into three parts. In the first part (Chapter 2) the impact response of thin monolithic …
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The 3D in-situ stress field and its changes in geothermal reservoirs
Information on the contemporary in-situ stress state of the earth’s crust is essential for geotechnical applications and physics-based seismic hazard assessment. Yet, stress data records for a data point are incomplete and their availability is usually not dense enough to allow conclusive …
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Mechanical Behavior of Metals Under Triaxial Stress: Apparatus and Experiments
Under combined axial-stress/external-pressure loadings, a solid specimen experiences a truly three-dimensional, homogenous stress state comprised of a uniform axial stress in conjunction with radial and circumferential stresses equal to the negative of the pressure, -P. Through independent computer …
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A Computer Vision Approach to Stress Determination in Blisters, and a Fatigue-Based Method Framework for Testing Defect Development
… of this project. Prior efforts to determine the stress state present in the pressurized membrane blister test, however, have required constitutive properties of the membrane (Young's modulus and Poisson's ratio), along with Hencky's classic model for circular membrane stresses. Herein we describe …
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An investigation of the critical timescales needed for digging in wet and dry soil using a biomimetic burrowing robot
… for applications such as sensor placement. The stress state of the soil around the robot was analyzed, and a target stress state for dry soil digging was found. Then, the two possible modes of soil collapse were investigated and used to determine how quickly the robot would have to contract to …
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Computational optimization methods for modeling the effect of muscle forces on bone strength adaptation
… forces acting within the system studied, the stresses they induce within the bones of the system, and the ensuing adaptations of the shape of one of these bones, altering its strength. This is accomplished through the use of gradient based optimization methods, finite element methods, and …
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Failure strength and mechanism of composite laminates under multiaxial loading conditions
… reinforced composite laminates in an in-plane stress state has been conducted. Different types of biaxial specimens and associated test fixtures were developed and employed in the study. Standard IITRI specimens were used to determine tensile and compressive failure strengths of G-10 composite …
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Experimental investigation and constitutive modeling of the large deformation behavior of anisotropic steel sheets undergoing strain-induced phase transformation
… The experimental program for different stress states includes experiments for uniaxial tension, uniaxial compression, equi-biaxial tension, pure shear, and transverse plane strain tension. The resulting experimental data demonstrate the influence of both the stress triaxiality and Lode …
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Small strain stiffness of fine grained soils
… in two computer controlled hydraulic stress path cells so that it was possible to measure the very small strain stiffness of the soil at' any stage of a triaxial stress path test and compare it directly to shear nioduli obtained at larger strain levels. The electronics required to run …
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