Investigating active slip planes in tantalum under compressive load: Crystal plasticity and slip trace analyses of single crystals

ABSTRACTA detailed study of deformation of NiAl single crystals in two soft orientations, <110> and <111>, has been conducted. The Schmid factor favors {100} slip in the former and {110} slip in the latter. Detailed dislocation analysis, critical resolved shear stress measurements, and slip trace analysis have been performed to determine the nature of dislocation motion and interactions in this material. Particular attention is given to prismatic loops formed during deformation, since the shapes of these loops reveal the active slip planes. Similar loop morphologies observed in elevated temperature [001] oriented tensile specimens are also discussed.

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Dislocation Boundaries and Slip Systems in Uniaxially Deformed Crystals

MRS Proceedings ◽

10.1557/proc-683-bb1.8.1 ◽

2001 ◽

Vol 683 ◽

Author(s):

Grethe Winther ◽

Xiaoxu Huang ◽

Søren Fæster Nielsen ◽

John Wert

Keyword(s):

Single Crystal ◽

Single Crystals ◽

Crystal Orientation ◽

Boundary Plane ◽

Slip Systems ◽

Crystal Boundary ◽

Secondary Slip ◽

Slip Planes ◽

Planar Dislocation ◽

Active Slip

ABSTRACTThe dislocations in the extended planar dislocation boundaries formed during deformation are generated by the active slip systems. Investigation of the boundaries is therefore a tool to obtain information on the active slip systems. Here, the orientation of the dislocation boundaries in uniaxially deformed aluminum poly- and single crystals are compared. It is found that the single crystal boundary planes are consistent with those found in polycrystals, indicating that the active slip systems in single and polycrystals are the same. However, boundaries are closer to the slip planes in the single crystals. This is taken as an indication that the secondary slip systems are more active in the polycrystal. The orientation of the boundary plane varies with the crystal orientation in a way that is consistent with activation of the five most stressed slip systems.

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An Analysis of Primary Creep of Nickel-Base Superalloy Single Crystals

Journal of Applied Mechanics ◽

10.1115/1.3408607 ◽

1970 ◽

Vol 37 (3) ◽

pp. 759-764 ◽

Cited By ~ 16

Author(s):

P. R. Paslay ◽

C. H. Wells ◽

G. R. Leverant

Keyword(s):

Single Crystals ◽

Quantitative Agreement ◽

Primary Creep ◽

Tensile Creep ◽

Nickel Base Superalloy ◽

Strain Rates ◽

Slip Planes ◽

Nickel Base ◽

Base Superalloy ◽

Active Slip

The orientation and stress dependence of the primary creep rate in single crystals of a nickel-base superalloy is predicted from crystallographic deformation mechanisms. An experimentally determined relationship between the deformation rate and applied stress is employed to calculate the independent contributions of each of the possible slip systems to the strain rate. Calculations were made for single crystals of a nickel-base superalloy tested in tensile creep at 1400 deg F, at which temperature the active slip planes are known to be {111}, and the slip directions either 〈110〉 or 〈112〉 at high or low strain rates, respectively. Comparison with measured primary creep rates showed the 〈110〉 contribution to be negligible and that while semi-quantitative agreement with the 〈112〉 analysis was obtained, an accurate prediction of creep rates may require inclusion of strain hardening in the analysis.

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Characteristic stepwise strain hardening behaviour induced by slip and twinning of large-deformed copper single crystals: crystal plasticity modelling and simulation

The Philosophical Magazine A Journal of Theoretical Experimental and Applied Physics ◽

10.1080/14786435.2021.1892914 ◽

2021 ◽

pp. 1-29

Author(s):

Ning Guo ◽

Bingtao Tang ◽

Jiyuan Liu ◽

Zongan Luo

Keyword(s):

Strain Hardening ◽

Single Crystals ◽

Crystal Plasticity ◽

Modelling And Simulation ◽

Copper Single Crystals

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Volume Texture of a Deformed Quartzite Observed With U-Stage Microscopy and Neutron Diffractometry

Textures and Microstructures ◽

10.1155/tsm.31.239 ◽

1999 ◽

Vol 31 (4) ◽

pp. 239-248 ◽

Cited By ~ 5

Author(s):

H. Ghildiyal ◽

E. Jansen ◽

A. Kirfel

Keyword(s):

Neutron Diffraction ◽

Pole Figure ◽

North West ◽

Pole Figures ◽

Slip Planes ◽

Subsequent Calculation ◽

Kaoko Belt ◽

Universal Stage ◽

Active Slip

The volume texture of a naturally deformed quartzite from the Kaoko belt, North-West Namibia, has been analysed by both universal stage microscopy and neutron diffraction. Universal stage microscopy is restricted to the determination of the base pinacoid preferred orientation in quartzite. For a more complete description of the texture, the orientations of additional crystal planes, such as first and second order prisms as well as positive and negative rhombs, must be known. Neutron methods allow the evaluation of pole figures of all Bragg reflecting planes, of which those of the first order prisms being considered to be the most active slip planes, are of particular interest. Drawbacks of neutron diffraction, i.e. the faking of an eventually absent inversion centre and lack of resolution, can be overcome by pole figure inversion and subsequent calculation of desired pole figures. Both, universal stage microscopy and neutron diffraction yield well comparable results, of course only with respect to the pole figure of the c-axis.

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