Ternary relation among stacking fault energy, grain size and twin nucleation size in nanocrystalline and ultrafine grained CuAl alloys

The effect of grain size and stacking fault energy (SFE) on the strain hardening rate behavior under plane strain compression (PSC) is investigated for pure Cu and binary Cu-Al alloys containing 1, 2, 4.7, and 7 wt. % Al. The alloys studied have a wide range of SFE from a low SFE of 4.5 mJm−2for Cu-7Al to a medium SFE of 78 mJm−2for pure Cu. A series of PSC tests have been conducted on these alloys for three average grain sizes of ~15, 70, and 250 μm. Strain hardening rate curves were obtained and a criterion relating twinning stress to grain size is established. It is concluded that the stress required for twinning initiation decreases with increasing grain size. Low values of SFE have an indirect influence on twinning stress by increasing the strain hardening rate which is reflected in building up the critical dislocation density needed to initiate mechanical twinning. A study on the effect of grain size on the intensity of the brass texture component for the low SFE alloys has revealed the reduction of the orientation density of that component with increasing grain size.

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Grain size effect on deformation twin thickness in a nanocrystalline metal with low stacking-fault energy

Journal of Materials Research ◽

10.1557/jmr.2019.194 ◽

2019 ◽

Vol 34 (13) ◽

pp. 2398-2405

Author(s):

Yusheng Li ◽

Liangjuan Dai ◽

Yang Cao ◽

Yonghao Zhao ◽

Yuntian Zhu

Keyword(s):

Grain Size ◽

Size Effect ◽

Deformation Twin ◽

Stacking Fault ◽

Stacking Fault Energy ◽

Grain Size Effect ◽

Nanocrystalline Metal ◽

Image Position ◽

Twin Thickness

Abstract

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Dependency modeling of steady state grain size on the stacking fault energy through severe plastic deformation

Materials Letters ◽

10.1016/j.matlet.2015.07.041 ◽

2015 ◽

Vol 159 ◽

pp. 410-412 ◽

Cited By ~ 4

Author(s):

H. Parvin ◽

M. Kazeminezhad

Keyword(s):

Plastic Deformation ◽

Grain Size ◽

Steady State ◽

Severe Plastic Deformation ◽

Stacking Fault ◽

Stacking Fault Energy

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Combined effects of crystallographic orientation, stacking fault energy and grain size on deformation twinning in fcc crystals

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

10.1080/14786430802438168 ◽

2008 ◽

Vol 88 (24) ◽

pp. 3011-3029 ◽

Cited By ~ 57

Author(s):

W.Z. Han ◽

Z.F. Zhang ◽

S.D. Wu ◽

S.X. Li

Keyword(s):

Grain Size ◽

Crystallographic Orientation ◽

Deformation Twinning ◽

Stacking Fault ◽

Stacking Fault Energy ◽

Combined Effects

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Unique Features of Ultrafine-Grained Microstructures in Materials Having Low Stacking Fault Energy

Materials Science Forum ◽

10.4028/www.scientific.net/msf.659.171 ◽

2010 ◽

Vol 659 ◽

pp. 171-176 ◽

Cited By ~ 1

Author(s):

Jenő Gubicza ◽

Nguyen Q. Chinh ◽

János L. Lábár ◽

Zoltán Hegedűs ◽

Terence G. Langdon

Keyword(s):

Equal Channel Angular Pressing ◽

Room Temperature ◽

Strong Dependence ◽

Stacking Fault ◽

Stacking Fault Energy ◽

Controlled Processes ◽

Angular Pressing ◽

Ultrafine Grained ◽

Number Of Passes

The evolution of the microstructure during processing by equal-channel angular pressing (ECAP) in silver having extremely low stacking fault energy was studied up to 16 passes. It was shown that at high strains the contribution of twinning to deformation increased at the expense of dislocation-controlled processes. It was also found that during storage at room temperature (i.e. at the temperature of ECAP) there was a self-annealing of the severely deformed microstructure after 1 month and its degree was revealed to have a strong dependence on the number of passes.

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