@article {2341,
	title = {Resolving crystallographic geometrically necessary dislocations in three dimensions in a hexagonal close packed titanium alloy},
	journal = {Model. Simul. Mat. Sci. Eng.},
	volume = {32},
	year = {2024},
	pages = {065035},
	abstract = {<p>
	Abstract Geometrically necessary dislocation (GND) content is measured from mm3-scaled Ti7Al three-dimensional (3D) microstructural data using a theory extended for hexagonal close packed crystals, which accounts for basal, prismatic and pyramidal \&lang; c + a \&rang; type dislocation content. The Ti7Al samples have been mechanically pre-strained to two different strain levels, and will then be strained along the same axis in uniaxial tension during simulation. Both inter- and intragranular GNDs across the microstructures have been characterized, with a large contribution of pyramidal \&lang; c + a \&rang; GNDs, consistent with the relative slip activity involved in pre-straining. The spatially resolved crystallographic GND distributions within the 3D microstructures are used to instantiate a microstructure model for forward modeling deformation simulations by a dislocation density hardening elasto-viscoplastic fast Fourier transform framework. Coarsening the voxel resolution during the initial microstructure construction procedure is shown to strongly impact both the magnitude and spatial distribution of the GNDs and in turn the forward deformation response of the pre-strained material. This study indicates that the voxel resolution desired when transferring from measured to model microstructures need not only be proportionally scaled with the microstructure but also sufficiently fine to capture the subgranular orientation gradients that may already be present in the material.
</p>
},
	author = {Witzen, Wyatt A and Lamb, James D and Arul Kumar, Mariyappan and Echlin, McLean P and Pollock, Tresa M and Beyerlein, Irene J}
}
@article {2311,
	title = {Resolving crystallographic geometrically necessary dislocations in three dimensions in a hexagonal close packed titanium alloy},
	journal = {Model. Simul. Mat. Sci. Eng.},
	volume = {32},
	year = {2024},
	pages = {065035},
	abstract = {<p>
	Abstract Geometrically necessary dislocation (GND) content is measured from mm3-scaled Ti7Al three-dimensional (3D) microstructural data using a theory extended for hexagonal close packed crystals, which accounts for basal, prismatic and pyramidal \&lang; c + a \&rang; type dislocation content. The Ti7Al samples have been mechanically pre-strained to two different strain levels, and will then be strained along the same axis in uniaxial tension during simulation. Both inter- and intragranular GNDs across the microstructures have been characterized, with a large contribution of pyramidal \&lang; c + a \&rang; GNDs, consistent with the relative slip activity involved in pre-straining. The spatially resolved crystallographic GND distributions within the 3D microstructures are used to instantiate a microstructure model for forward modeling deformation simulations by a dislocation density hardening elasto-viscoplastic fast Fourier transform framework. Coarsening the voxel resolution during the initial microstructure construction procedure is shown to strongly impact both the magnitude and spatial distribution of the GNDs and in turn the forward deformation response of the pre-strained material. This study indicates that the voxel resolution desired when transferring from measured to model microstructures need not only be proportionally scaled with the microstructure but also sufficiently fine to capture the subgranular orientation gradients that may already be present in the material.
</p>
},
	author = {Witzen, Wyatt A and Lamb, James D and Arul Kumar, Mariyappan and Echlin, McLean P and Pollock, Tresa M and Beyerlein, Irene J}
}
@article {2316,
	title = {On the role of geometrically necessary dislocations in void formation and growth in response to shock loading conditions in wrought and additively manufactured Ta},
	journal = {J. Mater. Res. Technol.},
	volume = {31},
	year = {2024},
	pages = {3035{\textendash}3049},
	author = {Lamb, James D and Mullin, Kaitlyn M and Christodoulou, Paul G and Witzen, Wyatt A and Echlin, McLean P and Beyerlein, Irene J and Pollock, Tresa M}
}
