Crystal plasticity finite element modelling of coarse-grained <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" altimg="si98.svg"><mml:mrow><mml:mi>α</mml:mi></mml:mrow></mml:math>-uranium

It is well known that titanium and some titanium alloys creep at ambient temperature, resulting in a significant fatigue life reduction when a stress dwell is included in the fatigue cycle. It is thought that localised time dependent plasticity in 'soft' grains oriented for easy plastic slip leads to load shedding and an increase in stress within a neighbouring 'hard' grain * Corresponding author E-mail address: yi.xiong@materials.ox.ac.uk (Yi Xiong) have a significant effect on stress redistribution to hard grain orientations during cold dwell fatigue. Author ContributionsThis work formed part of a larger testing campaign proposed by AJW and carried out at Diamond Light Source by YX, PK, CTN, DMC, CMM & AJW. PK oversaw preparation of test pieces and preliminary characterisation undertaken by YX, CMM and PK. CTN and PK setup and guided use of the ETMT system. YX, PK, DMC and AJW developed data analysis procedures. YX carried out crystal plasticity simulations supervised by ET who supplied the UMAT code. YX drafted the initial manuscript, with all authors contributing to and agreeing the final version.

show abstract

“…given by , is rotated in to the lattice orientation frame through the rotation matrix to give the lattice strain 0 as follows [32]:…”

Section: Methodsmentioning

confidence: 99%

Cold Creep of Titanium: Analysis of Stress Relaxation Using Synchrotron Diffraction and Crystal Plasticity Simulations

Karamched

Nguyen

et al. 2020

SSRN Journal

Self Cite

View full text Add to dashboard Cite

show abstract

“…The symmetry plane was fixed from translation in the normal direction, x 2 = 0, the nodes on the top surface were traction free, while the remaining four surfaces of the cube were fixed. Elastic anisotropy was used with the following elastic constants for copper: Further details on the UMAT can be found in [60,63,64,65,62,66]. Simulations provide direct comparison with the EF scratch test.…”

Section: Crystal Plasticity Finite Element Modellingmentioning

confidence: 99%

Scratching the Surface: Elastic Rotations Beneath Nanoscratch and Nanoindentation Tests

et al. 2020

View full text Add to dashboard Cite

This is a PDF file of an article that has undergone enhancements after acceptance, such as the addition of a cover page and metadata, and formatting for readability, but it is not yet the definitive version of record. This version will undergo additional copyediting, typesetting and review before it is published in its final form, but we are providing this version to give early visibility of the article. Please note that, during the production process, errors may be discovered which could affect the content, and all legal disclaimers that apply to the journal pertain.

show abstract

“…The MARMOT model also includes some modifications presented in Ref. [16], primarily temperature dependence of the plastic behavior; however, the exact form of the temperature dependence has been developed for this work. Both the VPSC model and the finite element model are based on dislocation motion within slip systems.…”

Section: Modelsmentioning

confidence: 99%

“…Following the notation in Ref. [16], each slip system is denoted by α, where α = 1...8, and each twin system is denoted by β, where β = 1, 2. Wall slip occurs for α = 1, floor slip for α = 2, chimney slip for α = 3, 4, roof slip for α = 5...8, and the {130} twin system is for β = 1, 2.…”

Section: Modelsmentioning

confidence: 99%

See 1 more Smart Citation

Lower length scale informed improvements to Bison U-Pu-Zr fuel swelling model

Aagesen

Jokisaari

2020

View full text Add to dashboard Cite

Due to renewed interest in metallic fuels from the U-(Pu)-Zr material system, significant improvements have recently been made to BISON's capability to simulate metallic fuel, particularly in the area of swelling. In this report, lower length scale simulations that have been conducted to inform the engineering-scale models in BISON during FY20 are described. For the high-temperature regions of the fuel that are dominated by the γ phase of U-(Pu)-Zr, two new models for swelling have implemented in BISON. Phase-field simulations were conducted to calculate parameters for these and other BISON models that control when gaseous swelling ceases and fission gas release begins. For the low-temperature regions of the fuel dominated by the α phase of uranium, microstructurally resolved simulations of pore growth and crystal deformation were performed to understand the effect of irradiation-generated crystal shape changes. Conformally meshed microstructures with pores were simulated with a crystal plasticity model and with a burnup eigenstrain model. Plastic deformation will not cause pore size to increase; burnup eigenstrain (irradiation-induced crystal shape changes) will increase the volume of existing porosity and cause it to become anisotropic in shape. Additional model development work for early-stage fission gas cluster/bubble formation in the γ phase were performed, by coupling with defect clustering within cluster dynamics framework. Sensitivity analysis were conducted to identify the critical thermo-kinetic parameters needed for rigorous assessment.

show abstract

Crystal plasticity finite element modelling of coarse-grained α-uranium

Cited by 25 publications

References 47 publications

Cold Creep of Titanium: Analysis of Stress Relaxation Using Synchrotron Diffraction and Crystal Plasticity Simulations

Cold Creep of Titanium: Analysis of Stress Relaxation Using Synchrotron Diffraction and Crystal Plasticity Simulations

Scratching the Surface: Elastic Rotations Beneath Nanoscratch and Nanoindentation Tests

Lower length scale informed improvements to Bison U-Pu-Zr fuel swelling model

Contact Info

Product

Resources

About