The Relationship between Mg Content and Extra-Hardening in Ultrafine Grained Al-Mg Alloy by SPD

Severe Plastic Deformation (SPD) process is one of methods for obtaining UFG-Al. It was reported in SPD-processed Al alloy that the extra-hardening due to work hardening caused by accumulated dislocation in the grains. In Al-Mg alloy, Mg decreases the stacking fault energy in this alloy, and dislocation tends to accumulate in the grains. In this study, Al-Mg alloy with various Mg contents were processed by Equal-Channel Angular Pressed (ECAP) which was one of SPD and annealed after processed ECAP. The relationship between Mg content and magnitude of extra-hardening was investigated. In ECAPed Al-3mass%Mg alloy, it was thought that extra-hardening was caused. Magnitude of extra-hardening was increased with increasing Mg content.

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Stability of Ultrafine-Grained Microstructure in Fcc Metals Processed by Severe Plastic Deformation

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.465.195 ◽

2011 ◽

Vol 465 ◽

pp. 195-198 ◽

Cited By ~ 11

Author(s):

Jenő Gubicza ◽

Nguyen Q. Chinh ◽

Sergey V. Dobatkin ◽

E. Khosravi ◽

Terence G. Langdon

Keyword(s):

Thermal Stability ◽

Plastic Deformation ◽

Dislocation Density ◽

Severe Plastic Deformation ◽

Room Temperature ◽

Stacking Fault ◽

Stacking Fault Energy ◽

High Dislocation Density ◽

Ultrafine Grained ◽

The Stability

The thermal stability of ultrafine-grained (UFG) microstructure in face centered cubic metals processed by severe plastic deformation (SPD) was studied. The influence of the SPD procedure on the stability was investigated for Cu samples processed by Equal-Channel Angular Pressing (ECAP), High-Pressure Torsion (HPT), Multi-Directional Forging and Twist Extrusion at room temperature (RT). It is found that HPT results in the lowest thermal stability due to the very high dislocation density. Furthermore, the effect of the low stacking fault energy of Ag on the stability is also investigated. It is revealed that the UFG microstructure produced in Ag by ECAP is recovered and recrystallized during storage at room temperature. The driving force for this unusual recovery and recrystallization is the high dislocation density developed during ECAP due to the high degree of dislocation dissociation caused by the very low stacking fault energy of Ag.

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Extra-Hardening of SPD-Processed Al-Mg Alloy with Minimum Grain Sizes

Materials Science Forum ◽

10.4028/www.scientific.net/msf.1016.952 ◽

2021 ◽

Vol 1016 ◽

pp. 952-956

Author(s):

Taiki Morishige ◽

Yuto Suzuki ◽

Toshihide Takenaka

Keyword(s):

Grain Size ◽

Large Strain ◽

High Strength ◽

Stacking Fault ◽

Stacking Fault Energy ◽

Mg Alloy ◽

Solid Solution Alloy ◽

Al Alloy ◽

Refinement Mechanism ◽

Mg Content

Severe plastic deformation (SPD) processing of Al alloys could obtain high strength by grain refinement mechanism. The minimum grain size of Al alloy, obtained at higher strain rate at low temperature, is determined the stacking fault energy of the alloy. SPD-processed pure Al metal, has high stacking fault energy, has relatively large grain size. During SPD processing, large strain is introduced, and the dislocation is rearranged in the specimen. The re-arrangement of dislocation in SPD-processed Al alloy with intermediate stacking fault energy significantly delayed, thus the strain remains in the grain interior. The extra-hardening, a kind of strain hardening, results from an incomplete of dynamic recrystallization during SPD processing. Al-Mg solid solution alloy has intermediate stacking fault energy and the minimum grain size of this alloy approaches about 200 nm after SPD. The mechanical property of this alloy is remarkably higher than the predictable strength by Hall-Petch relationship due to the extra-hardening. In addition, the increase in strength by the extra-hardening varies with the Mg content of Al-Mg alloy. In this study, the effect of Mg content, i.e. the stacking fault energy of the alloy, on the degree of the extra-hardening of SPD-processed Al-Mg alloy was investigated in terms of the dislocation density and low-angle grain boundary of the alloy.

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Investigations on Microstructure Evolution and Deformation Behavior of Aged and Ultrafine Grained Al-Zn-Mg Alloy Subjected to Severe Plastic Deformation

Materials Science Forum ◽

10.4028/www.scientific.net/msf.667-669.253 ◽

2010 ◽

Vol 667-669 ◽

pp. 253-258

Author(s):

Wei Ping Hu ◽

Si Yuan Zhang ◽

Xiao Yu He ◽

Zhen Yang Liu ◽

Rolf Berghammer ◽

...

Keyword(s):

Electron Microscopy ◽

Mechanical Properties ◽

Plastic Deformation ◽

Grain Size ◽

Severe Plastic Deformation ◽

Microstructure Evolution ◽

Deformation Behavior ◽

Deformation Mechanisms ◽

Mg Alloy ◽

Ultrafine Grained

An aged Al-5Zn-1.6Mg alloy with fine η' precipitates was grain refined to ~100 nm grain size by severe plastic deformation (SPD). Microstructure evolution during SPD and mechanical behaviour after SPD of the alloy were characterized by electron microscopy and tensile, compression as well as nanoindentation tests. The influence of η' precipitates on microstructure and mechanical properties of ultrafine grained Al-Zn-Mg alloy is discussed with respect to their effect on dislocation configurations and deformation mechanisms during processing of the alloy.

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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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Mechanical Properties of Ultrafine-Grained Al-Mg Alloy Produced by Severe Plastic Deformation

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.743.203 ◽

2017 ◽

Vol 743 ◽

pp. 203-206 ◽

Cited By ~ 9

Author(s):

Alexander A. Kozulin ◽

Vladimir A. Krasnoveikin ◽

Vladimir A. Skripnyak ◽

Evgeny N. Moskvichev ◽

Valery E. Rubtsov

Keyword(s):

Mechanical Properties ◽

Plastic Deformation ◽

Severe Plastic Deformation ◽

High Efficiency ◽

Physical And Mechanical Properties ◽

Treatment Method ◽

Mg Alloy ◽

Complex Investigation ◽

Angular Pressing ◽

Ultrafine Grained

This study examines the effect of severe plastic deformation on the physical and mechanical properties of a light structural Al-Mg alloy. Severe plastic deformation has been performed by equal channel angular pressing through a die with an angle of 90° between the channels to produce ultrafine-grained structure in specimens of studied alloy. A complex investigation of the physical and mechanical properties of the processed alloy has been carried out to examine the microstructure and texture, and to measure microhardness, yield stress and ultimate tensile strength. The obtained results demonstrate high efficiency of the chosen treatment method and mode of producing a light ultrafine-grained alloy.

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Microstructure of low stacking fault energy silver processed by different routes of severe plastic deformation

Journal of Alloys and Compounds ◽

10.1016/j.jallcom.2011.10.070 ◽

2012 ◽

Vol 536 ◽

pp. S190-S193 ◽

Cited By ~ 14

Author(s):

Zoltán Hegedűs ◽

Jenő Gubicza ◽

Megumi Kawasaki ◽

Nguyen Q. Chinh ◽

Zsolt Fogarassy ◽

...

Keyword(s):

Plastic Deformation ◽

Severe Plastic Deformation ◽

Stacking Fault ◽

Stacking Fault Energy

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Hot Workability of Ultrafine-Grained Aluminum Alloy Produced by Severe Plastic Deformation of Al6063 Powder and Consolidation

Materials Science Forum ◽

10.4028/www.scientific.net/msf.667-669.979 ◽

2010 ◽

Vol 667-669 ◽

pp. 979-984 ◽

Cited By ~ 1

Author(s):

Hamed Asgharzadeh ◽

Abdolreza Simchi ◽

Hyoung Seop Kim

Keyword(s):

Plastic Deformation ◽

Severe Plastic Deformation ◽

Dynamic Recrystallization ◽

Strain Rate ◽

Hot Deformation ◽

Grain Structure ◽

Al Alloy ◽

Strain Rates ◽

Hot Workability ◽

Ultrafine Grained

Al6063 powder was subjected to severe plastic deformation via high-energy mechanical milling to prepare ultrafine-grained (UFG) aluminium alloy. Uniaxial compression test at various temperatures between 300 and 450 °C and strain rates between 0.01 and 1 s-1 was carried out to evaluate hot workability of the material. Microstructural studies were performed by EBSD and TEM. The average activation energy and strain rate sensitivity of the hot deformation process were determined to be 280 kJ mol-1 and 0.05, respectively. The deformation temperature and applied strain rate significantly affected the grain structure of UFG Al alloy. A finer grain structure was obtained at lower temperatures and higher strain rates. The formation of highly misoriented and equiaxed grains also revealed that dynamic recrystallization occurred upon hot deformation. Furthermore, elongated grains with high dislocation density were observed that disclosed partial dynamic recrystallization of the aluminum matrix.

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