Atomistic simulation of titanium. II. Structure of ⅓ 〈1210〉 screw dislocations and slip systems in titanium

Atomistic simulations are used to describe the ½<111> screw dislocation in tungsten. Two different embedded atom model (EAM) potentials and one bond-order potential (BOP) are compared. A new analytical approach for constructing asymmetrical screw dislocations is presented.

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Characterization of the High Temperature Dislocation Substructure of Mosi2

MRS Proceedings ◽

10.1557/proc-364-893 ◽

1994 ◽

Vol 364 ◽

Cited By ~ 4

Author(s):

J. P. Campbell ◽

H. Chang ◽

R. Gibala

Keyword(s):

High Temperature ◽

Deformation Behavior ◽

Dislocation Substructure ◽

Dislocation Climb ◽

Slip Systems ◽

Quantitative Characterization ◽

Temperature Variations ◽

Screw Dislocations ◽

Orientation Distributions

AbstractThe dislocation substructure of polycrystalline MoSi2 deformed in compression at temperatures ranging from 900°C to 1300°C has been investigated. Slip is found to occur primarily by <100> Burgers vectors. A quantitative characterization of the <100> dislocation substructure is developed for several deformation temperatures, including the slip systems present and the relative occurrence of each. Orientation distributions showing the screw/edge character of the <100> dislocations are generated at each deformation temperature. Variations in these distributions with temperature are noted, and the implications of these variations to the deformation behavior of MoSi2 are discussed. Notable observations include the onset of dislocation climb between 900°C and 1100°C, a strong preference for dislocations of mixed character at 900°C, and the complete absence of pure screw dislocations from 900°C to 1300°C.

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Size-dependent elastic interaction of screw dislocations with semi-infinite coating materials revealed by atomistic simulation and two dimensional analysis

Meccanica ◽

10.1007/s11012-015-0135-y ◽

2015 ◽

Vol 50 (8) ◽

pp. 2063-2075 ◽

Cited By ~ 1

Author(s):

Jia Li ◽

Qihong Fang ◽

YouWen Liu

Keyword(s):

Dimensional Analysis ◽

Atomistic Simulation ◽

Elastic Interaction ◽

Two Dimensional ◽

Coating Materials ◽

Screw Dislocations ◽

Size Dependent

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Influence of Dislocation Mobility on Room and High Temperature Ductility of -Oriented Nial Single Crystals

MRS Proceedings ◽

10.1557/proc-364-413 ◽

1994 ◽

Vol 364 ◽

Cited By ~ 1

Author(s):

M. A. Morris ◽

J. P. Perez ◽

R. Darolia

Keyword(s):

High Temperature ◽

Single Crystals ◽

Room Temperature ◽

Tensile Tests ◽

Slip Systems ◽

Dislocation Mobility ◽

Screw Dislocations ◽

Large Density ◽

Thin Foils

AbstractThe dislocation configurations produced by room and high temperature compression of <100> oriented single crystals of binary NiAl and in those containing iron and hafnium additions have been analysed and compared to those obtained by hardness indentation and TEM insitu tensile tests. Kinking occurs during room temperature compression such that <100> dislocations are activated in all cases but the iron-containing alloy also exhibited a large density of <111> screw dislocations. The latter however, appear immobile when they are created by hardness indentations of thin foils, while only pile-ups of <100> segments can propagate. Similarly, although different slip systems are present after high temperature compression, only <100> dislocation segments have been confirmed to be mobile after room temperature hardness indentation of these predeformed thin foils. The improvement in ductility observed at room temperature in the predeformed specimens of the binary and the iron containing alloys has been attributed to the increased production of these mobile <100> dislocations.

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