806 First-Principles Calculations of the Relation between Grain Boundary Energy and Grain Boundary Sliding of [110] Tilt Grain Boundaries in Aluminum

2007 ◽  
Vol 2007.20 (0) ◽  
pp. 253-254
Author(s):  
Yasuhiko INOUE ◽  
Tokuteru UESUGI ◽  
Kenji HIGASHI
Keyword(s):  
Grain Boundary ◽  
Grain Boundaries ◽  
First Principles ◽  
Boundary Energy ◽  
Grain Boundary Sliding ◽  
First Principles Calculations ◽  
Grain Boundary Energy ◽  
Boundary Sliding

Grain Boundary Structure and Sliding of Alumina Bicrystals

1999 ◽  
Vol 601 ◽  
Author(s):  
Y. Ikuhara ◽  
T. Watanabe ◽  
T. Yarnamoto ◽  
T. Saito ◽  
H. Yoshida ◽  
...  
Keyword(s):  
Grain Boundary ◽  
Grain Boundaries ◽  
Small Angle ◽  
Boundary Energy ◽  
High Resolution Electron Microscopy ◽  
Grain Boundary Sliding ◽  
Boundary Structure ◽  
Grain Boundary Energy ◽  
Grain Boundary Structure ◽  
Boundary Sliding

AbstractAlumina bicrystals were fabricated by a hot joining technique at 1500°C in air to obtain ten kinds of [0001] symmetric tilt grain boundaries which included small angle, CSL and high angle grain boundaries. Their grain boundary structures were investigated by high-resolution electron microscopy (HREM), and the respective grain boundary energies were systematically measured by a thermal grooving technique. It was found that grain boundary energy strongly depended on the grain boundary characters, e.g., there were large energy cusps at low Σ CSL grain boundaries. But, main part of grain boundary energy is likely to be due to the strain energy around the grain boundary, and the contribution of atomic configuration is not so large. Small angle grain boundaries were consisted of an array of partial dislocation with Burgers vector of 1/3[1100] to form the stacking faults between the dislocations. The behavior of grain boundary sliding was also investigated for typical grain boundaries by high-temperature creep test at 1400°C. As the result, the occurrence of grain boundary sliding was found to depend on the grain boundary atomic structure.

High-temperature grain boundary sliding behavior and grain boundary energy in cubic zirconia bicrystals

2004 ◽  
Vol 52 (8) ◽  
pp. 2349-2357 ◽  
Author(s):  
Hidehiro Yoshida ◽  
Kenji Yokoyama ◽  
Naoya Shibata ◽  
Yuichi Ikuhara ◽  
Taketo Sakuma
Keyword(s):  
High Temperature ◽  
Grain Boundary ◽  
Boundary Energy ◽  
Grain Boundary Sliding ◽  
Grain Boundary Energy ◽  
Cubic Zirconia ◽  
Boundary Sliding

First-Principles Calculations of Grain Boundary-Surface for Various Grain Boundaries with Different Energies in Aluminum

2007 ◽  
Vol 551-552 ◽  
pp. 331-336 ◽  
Author(s):  
Tokuteru Uesugi ◽  
Y. Inoue ◽  
Yorinobu Takigawa ◽  
Kenji Higashi
Keyword(s):  
Shear Strength ◽  
Grain Boundary ◽  
First Principles ◽  
Boundary Surface ◽  
Grain Boundary Sliding ◽  
Excess Energy ◽  
First Principles Calculations ◽  
Perfect Single Crystal ◽  
Boundary Sliding ◽  
The Ideal

The grain boundary surface is the excess energy of the grain boundary as the lattice on one side of the grain is translated relative to the lattice on the other side of the grain. The maximum in the slope of the grain boundary surface determines the ideal shear strength for the grain boundary sliding. We presented the ideal shear strength for the grain boundary sliding in aluminum Σ3(11 2)[110] tilt grain boundary from the first-principles calculations. The ideal shear strength for the grain boundary sliding was much smaller than the ideal shear strength of a perfect single crystal.

Dislocations in grain boundaries and grain boundary sliding

1967 ◽  
Vol 15 (5) ◽  
pp. 857-860 ◽  
Author(s):  
Y Ishida ◽  
M.Henderson Brown
Keyword(s):  
Grain Boundary ◽  
Grain Boundaries ◽  
Grain Boundary Sliding ◽  
Boundary Sliding

Research on Micro-Mechanism of Nanocomposite Ceramic in Two-Dimensional Ultrasound Grinding

2007 ◽  
Vol 359-360 ◽  
pp. 344-348 ◽  
Author(s):  
Bo Zhao ◽  
Yan Wu ◽  
Guo Fu Gao ◽  
Feng Jiao
Keyword(s):  
Grain Boundary ◽  
Grain Boundaries ◽  
Deformation Mechanism ◽  
Ground Surface ◽  
Grain Boundary Sliding ◽  
Second Phase ◽  
Two Dimensional ◽  
Composite Ceramics ◽  
Nano Composite ◽  
Boundary Sliding

Surface microstructure of nano-composite ceramics prepared by mixed coherence system and machined by two-dimensional ultrasonic precision grinding was researched using TEM, SEM, XRD detector and other equipments. Structure, formation mechanism and characteristic of metamorphic layer of ground surface of nano-composite ceramics were researched. The experiment shows micro deformation mechanism of ceramic material in two-dimensional ultrasound grinding is twin grain boundary and grain-boundary sliding for Al2O3, and it is crystal dislocation of enhanced phase, matrix grain boundary sliding, coordination deformation of intergranular second phase as well as its deformation mechanism for nano-composite ceramics. The fracture surfaces of nano-composite materials with different microscopic structure were observed using TEM and SEM. Research shows that ZrO2 plays an important influence on the generation and expansion of crack, and enhances the strength of grain boundaries. When grain boundaries is rich in the ZrO2 particles, the crack produced in grinding process will be prevented, and the surface with plastic deformation will be smooth. The results shows nanoparticles dispersed in grain boundary prevents crack propagation and makes materials fracture transgranularly which makes the processed surface fine.

First-principles study of grain boundary sliding inα−Al2O3

2007 ◽  
Vol 75 (18) ◽  
Author(s):  
Kaoru Nakamura ◽  
Teruyasu Mizoguchi ◽  
Naoya Shibata ◽  
Katsuyuki Matsunaga ◽  
Takahisa Yamamoto ◽  
...  
Keyword(s):  
Grain Boundary ◽  
First Principles ◽  
Grain Boundary Sliding ◽  
First Principles Study ◽  
Boundary Sliding

scholarly journals Hierarchical creep cavity formation in an ultramylonite and implications for phase mixing

Solid Earth ◽  
2017 ◽  
Vol 8 (6) ◽  
pp. 1193-1209 ◽  
Author(s):  
James Gilgannon ◽  
Florian Fusseis ◽  
Luca Menegon ◽  
Klaus Regenauer-Lieb ◽  
Jim Buckman
Keyword(s):  
Grain Size ◽  
Grain Boundary ◽  
Grain Boundaries ◽  
Finite Strain ◽  
Grain Boundary Sliding ◽  
Large Strains ◽  
Cavity Formation ◽  
Phase Mixing ◽  
Transient Phenomena ◽  
Boundary Sliding

Abstract. Establishing models for the formation of well-mixed polyphase domains in ultramylonites is difficult because the effects of large strains and thermo-hydro-chemo-mechanical feedbacks can obscure the transient phenomena that may be responsible for domain production. We use scanning electron microscopy and nanotomography to offer critical insights into how the microstructure of a highly deformed quartzo-feldspathic ultramylonite evolved. The dispersal of monomineralic quartz domains in the ultramylonite is interpreted to be the result of the emergence of synkinematic pores, called creep cavities. The cavities can be considered the product of two distinct mechanisms that formed hierarchically: Zener–Stroh cracking and viscous grain-boundary sliding. In initially thick and coherent quartz ribbons deforming by grain-size-insensitive creep, cavities were generated by the Zener–Stroh mechanism on grain boundaries aligned with the YZ plane of finite strain. The opening of creep cavities promoted the ingress of fluids to sites of low stress. The local addition of a fluid lowered the adhesion and cohesion of grain boundaries and promoted viscous grain-boundary sliding. With the increased contribution of viscous grain-boundary sliding, a second population of cavities formed to accommodate strain incompatibilities. Ultimately, the emergence of creep cavities is interpreted to be responsible for the transition of quartz domains from a grain-size-insensitive to a grain-size-sensitive rheology.

Effect of Grain Boundary Energy Anisotropy on Faceting and Migration of Low Angle Grain Boundaries

2014 ◽  
Vol 783-786 ◽  
pp. 1634-1639
Author(s):  
Dmitri A. Molodov ◽  
Jann Erik Brandenburg ◽  
Luis Antonio Barrales-Mora ◽  
Günter Gottstein
Keyword(s):  
Grain Boundary ◽  
Grain Boundaries ◽  
Elevated Temperatures ◽  
Boundary Energy ◽  
Migration Behavior ◽  
Grain Boundary Energy ◽  
Contrast Imaging ◽  
Orientation Contrast ◽  
And Migration ◽  
Twist Boundaries

The faceting and migration behavior of low angle <100> grain boundaries in high purity aluminum bicrystals was investigated. In-situ technique based on orientation contrast imaging was applied. In contrast to the pure tilt boundaries, which remained straight/flat and immobile during annealing at elevated temperatures, mixed tilt-twist boundaries readily assumed a curved shape and steadily moved under the capillary force. Computational analysis revealed that this behavior is due to the inclinational anisotropy of grain boundary energy, which in turn depends on boundary geometry – the energy of pure tilt low angle <100> boundaries is anisotropic, whereas that of mixed tilt-twist boundaries isotropic with respect to boundary inclination.

Sign in / Sign up

Export Citation Format

Share Document