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Results for “RESIDUAL STRESS”
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Lamination Process Induced Residual Stress in Glass-Glass vs. Glass-Backsheet Modules.
Abstract not provided.
Residual Stresses in Spent Nuclear Fuel Storage Canisters with Cold Spray Coatings
This report describes the development of cold spray (CS) process and its application to provide on overlay coating of metal welds with a surface crack in a spent nuclear fuel (SNF) storage canister and thereby remediate the canister from further propagation of the crack. This work informs aging management programs for the SNF canisters.
Laser Speckle Photometry for Residual Stress Diagnosis of Laser Powder Bed Fusion Processing
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Effect of Plume-Targeted Cooling on Residual Stress in Controlled Atmosphere Plasma Sprayed Metals
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Improved Weld Residual Stress Modeling System in BlackBear
This report presents enhancements to the MOOSE-based BlackBear application aimed at improving its capability to simulate welding and other thermo-mechanical manufacturing processes. Two primary avenues of improvement are pursued. First, to enhance user accessibility, we introduce a centralized default block restriction mechanism that ensures coverage checks are performed within user-specified default blocks. This default setting is applied consistently to all block-describable objects, such as variables, kernels, and more. In addition, we develop a modular action for moving heat source simulations, which integrates path file parsing, subdomain modification, and heat source kernel enforcement into a single, streamlined configuration. Second, to improve solver robustness, we implement an alternative method for assigning initial conditions to the updated active domain during the simulation, thereby enhancing convergence behavior. To validate the framework, we design and conduct several benchmark simulations, including heat conduction with progressive material addition, linear elasticity with time-dependent material deposition, and viscoplasticity model with isotropic hardening under similar conditions. Finally, we demonstrate the effectiveness of the proposed framework through large-scale thermo-mechanical welding simulations in both two and three dimensions.
A high-fidelity thermal-fluid-solid modeling approach to understand defect formation and residual stresses in additive manufacturing builds
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Predicting residual stress fields using a multiphysical model with adaptive remeshing: Model construction and validation
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A high-fidelity thermal-fluid-solid modeling approach to understand defect formation and residual stresses in additive manufacturing builds
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Validating residual stress predictions of an adaptively remeshed multiphysical resistance forge weld model
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Fracture Analysis of Cohesive Zone Models for Modeling Residual Stress Induced Delamination in Composite Structures
A fracture study of coupon-scale composite cylinders with embedded defects was conducted with an objective to assess and validate a modeling approach using two available cohesive material models. The study included experimental and simulation evaluations of initiation of crack growth and progression. Interrupted thermal experiments used acoustic emissions monitoring to identify the onset of crack progression during each cooling interval and ultrasonic scanning provided images of defect growth. Verification, validation, and uncertainty quantification (VVUQ) processes were performed in the assessment of the simulation predicted temperature at which crack propagation begins (quantity of interest). The Sobol sensitivity analysis identified the hoop direction elastic modulus in the carbon fiber reinforced polymer (CFRP) plies as the most influential parameter for simulations using both cohesive models, accounting for at least 70% of the variation in the temperature at crack propagation. The UQ temperature range for the Tvergaard-Hutchinson model was higher (more conservative) than the experimental acoustic measurement indicators of crack progression, while the temperature range for the Thouless-Parmigiani model enveloped the experimental data points for the primary defect size of 0.75 x 1 in. The simulations could not capture the stable crack growth indicated in the experiments. This is likely due to the models’ inability to represent anisotropic fracture toughness attributed to the structure of the orthotropic fiber weave in a woven composite laminate.
Residual Stress Development and Deformation of Wire-Arc Direct Energy Deposition Parts
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Validating the Use of Gaussian Process Regression for Adaptive Mapping of Residual Stress Fields
Probing the stress state using a high density of measurement points is time intensive and presents a limitation for what is experimentally feasible. Alternatively, individual strain fields used for determining stresses can be reconstructed from a subset of points using a Gaussian process regression (GPR). Results presented in this paper evidence that determining stresses from reconstructed strain fields is a viable approach for reducing the number of measurements needed to fully sample a component’s stress state. The approach was demonstrated by reconstructing the stress fields in wire-arc additively manufactured walls fabricated using either a mild steel or low-temperature transition feedstock. Effects of errors in individual GP reconstructed strain maps and how these errors propagate to the final stress maps were assessed. Implications of the initial sampling approach and how localized strains affect convergence are explored to give guidance on how best to implement a dynamic sampling experiment.
Analysis of retained austenite and residual stress distribution in Ni-Cr type high strength steel weld by neutron diffraction
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Multiscale Process Modeling of a Carbon Fiber/Epoxy Composite for Predicting Residual Stress and Strength
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Development of non-destructive methods for determining residual stress and fatigue damage in metals Monthly progress report
Ultrasonic measurements of stress and microwave measurements of fatigue damage in metal plates
Nondestructive evaluation of residual stress in low-carbon steel
The effects of the preferred orientation on the temperature dependence of ultrasonic velocity in low carbon steels are investigated. The sensitivity of the acousto-elastic constant to changes in microstructure is assessed as well as the possibility of determining some mechanical properties of a material by measuring the acousto-elastic constant.
Nondestructive evaluation of residual stress in low-carbon steel, introduction
The degree of insensitivity of the temperature dependence method to variations in preferred orientations in A508 low carbon steel specimens was determined. A pulsed phase locked loop was used to measure ultrasonic velocity in these specimens in the temperature range of 50 C below and above room temperature. Results are given in tables and indicate that the temperature dependence of ultrasonic longitudinal velocity in four specimens cut at different angles remains unchanged as a function of orientation within + or -2%. The variation of temperature dependence of ultrasonic shear velocity in the A508 steel as a function of applied stresses was also measured. Results show that values at zero stress are equal regardless of whether the polarization direction is parallel or perpendicular to the direction in which the stress is applied.