(DSF)n-graphene: Carbon semimetal with double stacking faults

The crystalline perfection of microwave plasma assisted chemical vapor deposited (MPACVD) diamond films grown under various conditions has been examined by TEM. Most CVD diamond films thus far reported contain a high density of defects, predominantly twins and stacking faults on {111} planes. We show that under appropriate growth conditions, these planar defects are eliminated from the center of the crystallites, and occur only at grain boundaries where the growing crystallites meet.

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Dislocations and stacking faults in stainless steel

Proceedings of the Royal Society of London Series A - Mathematical and Physical Sciences ◽

10.1098/rspa.1957.0105 ◽

1957 ◽

Vol 240 (1223) ◽

pp. 524-538 ◽

Cited By ~ 124

Keyword(s):

Electron Microscopy ◽

Transmission Electron Microscopy ◽

Stainless Steel ◽

Grain Boundaries ◽

Stacking Faults ◽

Stacking Fault ◽

Stacking Fault Energy ◽

Thin Sections ◽

Partial Dislocations ◽

Transmission Electron

Further experiments by transmission electron microscopy on thin sections of stainless steel deformed by small amounts have enabled extended dislocations to be observed directly. The arrangement and motion of whole and partial dislocations have been followed in detail. Many of the dislocations are found to have piled up against grain boundaries. Other observations include the formation of wide stacking faults, the interaction of dislocations with twin boundaries, and the formation of dislocations at thin edges of the foils. An estimate is made of the stacking-fault energy from a consideration of the stresses present, and the properties of the dislocations are found to be in agreement with those expected from a metal of low stacking-fault energy.

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The Structure of Dislocations in Low-Angle Grain Boundaries in the Diamond Cubic Lattice

MRS Proceedings ◽

10.1557/proc-5-33 ◽

1981 ◽

Vol 5 ◽

Cited By ~ 1

Author(s):

C.B. Carter

Keyword(s):

Grain Boundary ◽

Grain Boundaries ◽

Stacking Faults ◽

Burgers Vector ◽

Cubic Lattice ◽

Partial Dislocations ◽

Tilt Boundaries ◽

P Type ◽

Twist Boundaries

ABSTRACTDislocations in low-angle tilt boundaries exhibit a wide variety of Burgers vector including a/2<112> a<001> and a<111>. The dislocations are usually dissociated: Shohkley, stair-rod and Frank partial dislocations may each be formed together with associated intrinsic and extrinsic stackingfaults. Dislocations in low-angle {111} twist boundaries are usually assumed to dissociated by a glide mechanism to give two types of extended nodes, known as P–type and K–type, which contain intrinsic and extrinsic stacking-faults respectively. It is shown that dissociation by climb actually occurs for both types of grain boundary.

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Microscopic Description of Plasticity in Computer Generated Metallic Nanophase Samples

MRS Proceedings ◽

10.1557/proc-538-401 ◽

1998 ◽

Vol 538 ◽

Cited By ~ 2

Author(s):

M. Spaczér ◽

H. Van Swygenhoven ◽

A. Caro

Keyword(s):

Grain Boundaries ◽

Stacking Faults ◽

Atomic Displacement ◽

Grain Boundary Sliding ◽

Deformation Analysis ◽

Microscopic Description ◽

Grain Sizes ◽

Partial Dislocations ◽

Schmid Factor ◽

Boundary Sliding

AbstractWe report simulations on the plastic behaviour of nanocrystalline Ni and Cu with grain sizes in the range of 3-12 nm. We observe a change in deformation mechanism in both materials: at the smallest grain sizes all deformation is accommodated in the grain boundaries, while at higher grain sizes we observe intragrain deformation. Analysis of the atomic configurations shows that stacking faults are produced by the passage of partial dislocations generated and absorbed in opposite grain boundaries. In Cu, we observe the stacking faults at smaller grain sizes than in Ni (8 and 12nm, respectively), which is attributed to the lower stacking fault energy of copper. Dislocations appear on slip systems that are not necessarily those favoured by the Schmid factor. Atomic displacement analysis shows deformation starts at triple points, with grain boundary sliding followed by the creation of intragrain partial dislocations.

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Microstructure characterization of one-directionally oriented ulexite

Journal of Materials Research ◽

10.1557/jmr.1998.0099 ◽

1998 ◽

Vol 13 (3) ◽

pp. 778-783 ◽

Cited By ~ 1

Author(s):

Yumi H. Ikuhara ◽

Shinji Kondoh ◽

Koichi Kikuta ◽

Shin-ichi Hirano

Keyword(s):

Grain Boundary ◽

Grain Boundaries ◽

Small Angle ◽

Stacking Faults ◽

Contact Angles ◽

Light Transmittance ◽

High Angle ◽

Electron Dose ◽

Bundle Structure

Microstructures of ulexite were investigated by CTEM and low electron dose HREM. It was found that the longitudinal grains in ulexite were oriented to c-direction to form a bundle structure. There were a number of small-angle grain boundaries and stacking faults inside a grain in the ulexite. Cleavage microcracks and stacking faults were mostly introduced on the {010} of the ulexite. The high-angle grain boundaries mainly consisted of high coincidence boundaries, which was confirmed by a comparison of observed contact angles and calculated degree of coincidence at the boundaries. The light transmittance properties of the ulexite would depend on the defects such as stacking fault, small-angle grain boundary, and high-angle grain boundary.

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First-Principles Calculations of Stacking Faults and Grain Boundaries in Metals

MRS Proceedings ◽

10.1557/proc-213-57 ◽

1990 ◽

Vol 213 ◽

Cited By ~ 1

Author(s):

K. Hampel ◽

D.D. Vvedensky ◽

S. Crampin

Keyword(s):

Magnetic Properties ◽

Grain Boundary ◽

Grain Boundaries ◽

First Principles ◽

Stacking Faults ◽

First Principles Calculations ◽

Comprehensive Description ◽

Planar Defects ◽

Detailed Understanding ◽

Defect Energies

ABSTRACTA detailed understanding of planar defects plays an important role in the search for a comprehensive description of the mechanical behaviour of metals and alloys. We present calculations for isolated stacking faults and grain boundaries using the layer Korringa-Kohn-Rostoker method including an assessment of the force theorem, which has already proven itself in evaluating defect energies for elemental close-packed metals. These ab initio total energy calculations will be supplemented by a study of the changes in bonding and local magnetic properties near a symmetric Σ5 (310) grain boundary in Fe

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Grain boundaries and stacking faults in a Pm3n cubic mesophase

Liquid Crystals ◽

10.1080/026782999203823 ◽

1999 ◽

Vol 26 (10) ◽

pp. 1493-1499 ◽

Cited By ~ 16

Author(s):

S. D. HUDSON ◽

H.-T. JUNG ◽

P. KEWSUWAN ◽

V. PERCEC ◽

W.-D. CHO

Keyword(s):

Grain Boundaries ◽

Stacking Faults

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Lattice-plane curvature and small-angle grain boundaries in SiC bulk crystals

Journal of Applied Crystallography ◽

10.1107/s002188980503298x ◽

2006 ◽

Vol 39 (1) ◽

pp. 17-23 ◽

Cited By ~ 11

Author(s):

Christoph Seitz ◽

Ziad G. Herro ◽

Boris M. Epelbaum ◽

Rainer Hock ◽

Andreas Magerl

Keyword(s):

Grain Boundaries ◽

Small Angle ◽

Growth Front ◽

Large Radius ◽

Lattice Plane ◽

Bulk Crystals ◽

Rocking Curve ◽

One Dimensional ◽

Lattice Planes ◽

Crystal Growth Front

SiC crystals grown by the physical vapour transport process along the [001] direction show a curvature of the crystal growth front in correspondence with the shape of the isotherms. A large radius for the curvature of the isotherms enhances the formation of an extended facet. Under the facet, the lattice planes are flat with a high crystal quality as expressed by rocking-curve half widths of 0.022°. In the non-faceted region, the lattice planes become bent, following the shape of the isotherms with a radius of typically 0.5 to 0.8 m and an increased rocking-curve half width of 0.3°. A reduction of the growth rate from 300 µm h−1to 70 µm h−1does not affect this behaviour significantly. The lattice-plane curvature and the development of the facet are predominantly affected by the shape of the isotherms. For crystals grown in the [015] direction, the lattice planes adjust only in a one-dimensional manner to the isotherms. In all cases, the lattice-plane curvature results from the formation of a high density of small-angle grain boundaries. They are generated by the condensation of dislocations with Burgers vectors in theabplane.

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