Dynamic precipitation and dynamic recrystallization during hot deformation of a solutionized WE43 magnesium alloy

The objective of this work is to investigate the effect of dynamic precipitation on the hot deformation behaviour of magnesium. Mg-Al-Sn alloys have been designed using thermodynamic modeling software, FactSage, based on precipitation of Mg2Sn at hot deformation temperatures. Uniaxial compression has been introduced at the temperature range of 250-350 °C to enhance the formation of precipitates. The flow behaviour and microstructural evolvement were studied for a strain rate of 0.01 /sand deformation degree of 90 %. Dynamic recrystallization (DRX) occurs in this study and it is found that the volume percent of dynamic recrystallization and dynamically recrystallized grain size are related to the amount of precipitation formed during deformation. The formation of Mg2Sn precipitates during the dynamic recrystallization process may retard the dynamic recrystallization and slow down the grain growth by precipitation pinning effect at the DRX grain boundaries, resulting in a finer grain size.

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Effect of Initial Grain Size on Deformation Behavior and Dynamic Recrystallization of Magnesium Alloy AZ31

Materials Science Forum ◽

10.4028/www.scientific.net/msf.488-489.223 ◽

2005 ◽

Vol 488-489 ◽

pp. 223-226 ◽

Cited By ~ 21

Author(s):

Xu Yue Yang ◽

Masayoshi Sanada ◽

Hiromi Miura ◽

Taku Sakai

Keyword(s):

Magnesium Alloy ◽

Dynamic Recrystallization ◽

Grain Refinement ◽

Hot Deformation ◽

Structural Changes ◽

Kink Bands ◽

Alloy Az31 ◽

Continuous Dynamic Recrystallization ◽

Magnesium Alloy Az31 ◽

Continuous Dynamic

Hot deformation and associated structural changes were studied in compression of a magnesium alloy AZ31 with initial grain sizes (D0) of 22 µm and 90 µm at a temperature of 573K. D0 influences significantly the flow curve and the kinetics of grain refinement during hot deformation. For D0 = 22 µm, grain fragmentation takes place due to frequent formation of kink bands initially at corrugated grain boundaries and then in grain interiors in low strain, followed by full development of new fine grains in high strain. For D0 = 90 µm, in contrast, twinning takes place in coarser original grains, and then kink bands and new fine grains are formed mainly in finer ones at low strains. Then new grains are formed in necklace along the boundaries of coarse original grains, followed by their development into the grain interiors. Grain refinement in the Mg alloy can be concluded to result from a series of deformation-induced continuous reactions, they are essentially similar to continuous dynamic recrystallization (cDRX).

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Dynamic recrystallization and texture development during hot deformation of magnesium alloy AZ31

Transactions of Nonferrous Metals Society of China ◽

10.1016/s1003-6326(08)60228-9 ◽

2009 ◽

Vol 19 (1) ◽

pp. 55-60 ◽

Cited By ~ 64

Author(s):

Xu-yue YANG ◽

Ze-sheng JI ◽

H. MIURA ◽

T. SAKAI

Keyword(s):

Magnesium Alloy ◽

Dynamic Recrystallization ◽

Hot Deformation ◽

Texture Development ◽

Alloy Az31 ◽

Magnesium Alloy Az31

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Rate controlling mechanisms during hot deformation of Mg–3Gd–1Zn magnesium alloy: Dislocation glide and climb, dynamic recrystallization, and mechanical twinning

Materials & Design (1980-2015) ◽

10.1016/j.matdes.2014.12.020 ◽

2015 ◽

Vol 68 ◽

pp. 228-231 ◽

Cited By ~ 82

Author(s):

H. Mirzadeh ◽

M. Roostaei ◽

M.H. Parsa ◽

R. Mahmudi

Keyword(s):

Magnesium Alloy ◽

Dynamic Recrystallization ◽

Hot Deformation ◽

Mechanical Twinning ◽

Dislocation Glide

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Characterization of Hot Deformation Behavior and Processing Maps of Mg-3Sn-2Al-1Zn-5Li Magnesium Alloy

Metals ◽

10.3390/met9121262 ◽

2019 ◽

Vol 9 (12) ◽

pp. 1262 ◽

Cited By ~ 4

Author(s):

Yuhang Guo ◽

Yaodong Xuanyuan ◽

Chunnan Lia ◽

Sen Yang

Keyword(s):

Magnesium Alloy ◽

Dynamic Recrystallization ◽

Strain Rate ◽

Hot Deformation ◽

Processing Maps ◽

Compression Tests ◽

Softening Mechanism ◽

Signal Peak ◽

The Operating Mechanism ◽

The Stability

The dynamic microstructure evolution of Mg-3Sn-2Al-1Zn-5Li magnesium alloy during hot deformation is studied by hot compression tests over the temperature range of 200–350 °C under the strain rate of 0.001–1 s−1, whereafter constitutive equations and processing maps are developed and constructed. In most of cases, the material shows typical dynamic recrystallization (DRX) features, with a signal peak value followed by a gradual decrease. The value of Q (deformation activation energy) is 138.89414 kJ/mol, and the instability domains occur at high strain rate but the stability domains are opposite, and the optimum hot working parameter for the studied alloy is determined to be 350 °C/0.001 s−1 according to the processing maps. Within 200–350 °C, the operating mechanism of dynamic recrystallization (DRX) of Mg-3Sn-2Al-1Zn-5Li alloy during hot deformation is mainly affected by strain rate. Dynamic recrystallization (DRX) structures are observed from the samples at 300 °C/0.001 s−1 and 350 °C/0.001 s−1, which consist of continuous DRX (CDRX) and discontinuous DRX (DDRX). However, dynamic recovery (DRV) still dominates the softening mechanism. At the grain boundaries, mass dislocation pile-ups and dislocation tangle provide sites for potential nucleation. Meanwhile, flow localization bands are observed from the samples at 200 °C/1 s−1 and 250 °C/0.1 s−1 as the main instability mechanism.

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