scholarly journals Effect of blunt nanocracks on the splitting transformation of grain boundary dislocation piled up at triple junctions

2018 ◽  
Vol 141-142 ◽  
pp. 232-244 ◽  
Author(s):  
Yingxin Zhao ◽  
Lianyong Xu
Keyword(s):  
Grain Boundary ◽  
Triple Junctions ◽  
Boundary Dislocation

Two Investigations into Grain Boundary Structure

1977 ◽  
Vol 35 ◽  
pp. 688-691
Author(s):  
P. Humble
Keyword(s):  
Grain Boundary ◽  
Dark Field ◽  
Boundary Structure ◽  
Boundary Dislocation ◽  
Bright Field ◽  
Intrinsic Structure ◽  
Weak Beam ◽  
Grain Boundary Structure ◽  
Independent Information ◽  
Diffraction Patterns

There has been sustained interest over the last few years into both the intrinsic (primary and secondary) structure of grain boundaries and the extrinsic structure e.g. the interaction of matrix dislocations with the boundary. Most of the investigations carried out by electron microscopy have involved only the use of information contained in the transmitted image (bright field, dark field, weak beam etc.). Whilst these imaging modes are appropriate to the cases of relatively coarse intrinsic or extrinsic grain boundary dislocation structures, it is apparent that in principle (and indeed in practice, e.g. (1)-(3)) the diffraction patterns from the boundary can give extra independent information about the fine scale periodic intrinsic structure of the boundary.In this paper I shall describe one investigation into each type of structure using the appropriate method of obtaining the necessary information which has been carried out recently at Tribophysics.

On the first steps of grain boundary dislocation stress relaxations in copper

2004 ◽  
Vol 95 (4) ◽  
pp. 223-225 ◽  
Author(s):  
J. P. Couzinié ◽  
B. Décamps ◽  
L. Priester
Keyword(s):  
Grain Boundary ◽  
Boundary Dislocation ◽  
Dislocation Stress

Effect of Triple Junctions on Grain Boundary Migration

1998 ◽  
Vol 294-296 ◽  
pp. 517-520 ◽  
Author(s):  
Vera G. Sursaeva ◽  
U. Czubayko ◽  
Günter Gottstein ◽  
Lasar S. Shvindlerman
Keyword(s):  
Grain Boundary ◽  
Boundary Migration ◽  
Grain Boundary Migration ◽  
Triple Junctions

scholarly journals Grain-Boundary Sliding and Its Accommodation at Triple Junctions in Aluminum and Copper Tricrystals

2019 ◽  
Vol 60 (1) ◽  
pp. 86-92
Author(s):  
Tatsuya Okada ◽  
Hiromu Hisazawa ◽  
Akihiro Iwasaki ◽  
Shota Amimoto ◽  
Jun Miyaji ◽  
...  
Keyword(s):  
Grain Boundary ◽  
Grain Boundary Sliding ◽  
Triple Junctions ◽  
Boundary Sliding

Wandering and nanolaminated structures of grain boundary triple junctions in tungsten

2020 ◽  
Vol 260 ◽  
pp. 126980
Author(s):  
T.I. Mazilova ◽  
E.V. Sadanov ◽  
I.V. Starchenko ◽  
I.M. Mikhailovskij
Keyword(s):  
Grain Boundary ◽  
Triple Junctions ◽  
Boundary Triple

Deformation textures in pyrite from the Vangorda Pb-Zn-Ag deposit, Yukon, Canada

1993 ◽  
Vol 57 (386) ◽  
pp. 55-66 ◽  
Author(s):  
D. Brown ◽  
K. R. McClay
Keyword(s):  
Grain Boundary ◽  
Boundary Migration ◽  
Shear Zones ◽  
Grain Boundary Sliding ◽  
Ductile Deformation ◽  
Mining District ◽  
Strain Partitioning ◽  
Triple Junctions ◽  
Brittle Deformation ◽  
Deformation Textures

AbstractThe Vangorda Pb-Zn-Ag orebody is a 7.1 M tonne, polydeformed stratiform massive sulphide deposit in the Anvil mining district, Yukon, Canada. Five sulphide lithofacies have been identified within the desposit with a typical mineralogy of pyrite, sphalerite, galena, and barite. Pyrrhotite-sphaleritemagnetite assembalges are locally developed. Etched polished sections of massive pyrite ores display relict primary depositional pyrite textures such as colloform growth zoning and spheroidal/framboidal features. A wide variety of brittle deformation, ductile deformation, and annealing textures have been identified. Brittle deformation textures include thin zones of intense cataclasis, grain indentation and axial cracking, and grain boundary sliding features. Ductile deformation textures include strong preferred grain shape orientations, dislocation textures, grain boundary migration, dynamic recrystallisation and pressure solution textures. Post deformational annealing has produced grain growth with lobate grain boundaries, 120° triple junctions and idioblastic pyrite porphyroblasts. The distribution of deformation textures within the Vangorda orebody suggests strong strain partitioning along fold limbs and fault/shear zones, it is postulated that focussed fluid flow in these zones had significant effects on the deformation of these pyritic ores.

Effect of Ge-rich Si1−zGez Segregation on the Morphological Stability of NiSi1−uGeu Film Formed on Strained (001) Si0.8Ge0.2 Epilayer

2004 ◽  
Vol 810 ◽  
Author(s):  
H.B. Yao ◽  
D.Z. Chi ◽  
S. Tripathy ◽  
S.Y. Chow ◽  
W.D. Wang ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Transmission Electron Microscopy ◽  
High Resolution ◽  
Grain Boundary ◽  
Surface Morphology ◽  
Morphological Stability ◽  
Triple Junctions ◽  
Cross Sectional ◽  
Transmission Electron ◽  
Segregation Process

ABSTRACTThe germanosilicidation of Ni on strained (001) Si0.8Ge0.2, particularly Ge segregation, grain boundary grooving, and surface morphology, during rapid thermal annealing (RTA) was studied. High-resolution cross-sectional transmission electron microscopy (HRXTEM) suggested that Ge-rich Si1−zGez segregation takes place preferentially at the germanosilicide/Si1−xGex interface, more specifically at the triple junctions between two adjacent NiSi1−uGeu grains and the underlying epi Si1−xGex, and it is accompanied with thermal grooving process. The segregation process accelerates the thermal grooving of NiSi1−uGeu grain boundaries at the interface. The segregation-accelerated grain boundary grooving has significant effect on the surface morphology of NiSi1−uGeu films in Ni-SiGe system.

Thermodynamics and Kinetics of 1D Structural Elements and Stability of Nanocrystalline Materials

2015 ◽  
Vol 5 ◽  
pp. 173-195
Author(s):  
Günter Gottstein ◽  
Lazar S. Shvindlerman
Keyword(s):  
Grain Boundary ◽  
Grain Growth ◽  
Triple Junction ◽  
Nanocrystalline Materials ◽  
Triple Line ◽  
Second Phase ◽  
Structural Elements ◽  
Triple Junctions ◽  
Line Energy ◽  
The Impact

Grain boundary triple junctions are the structural elements of a polycrystal. Recently it was recognized that they can strongly impact the microstructural evolution, and therefore there engender new opportunities to control and to design the grain microstructure of fine-grained and nanocrystalline materials due to their effect on recovery, recrystallization and grain growth. The measurement of triple junction energy and mobility is thus of great importance. The line energy of a triple junction constructs an additional driving force of grain growth. Taking the triple line energy into account, a modified form of the Zener force and the Gibbs-Thomson relation can be derived to reveal the influence of the triple line energy on second phase particles and the change of the equilibrium concentration of vacancies in the vicinity of voids at a grain boundary. The impact of triple junctions on the sintering of nanopowders is discussed. The role of “grain boundary - free surface” triple lines in the adhesive contact formation between spherical nanoparticles is considered. It is shown that there is a critical value of the triple line energy above which the nanoparticles do not stick together. Based on this result, a new nanoparticle agglomeration mechanism is proposed, which accounts for the formation of large agglomerates of crystallographically aligned nanoparticles during the nanopowder processing.

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