Dynamic Recrystallization of Mg-8Gd-3Y-1Nd-0.5Zr Alloy during Hot Deformation

Uniaxial hot compression was conducted on Gleeble-3500 thermo simulation machine. Based on stress-strain curves, the constitutive relationship and the dynamic recrystallization kinetics model of Mg-8Gd-3Y-1Nd-0.5Zr were established. Simultaneously, dynamic recrystallization mechanism of this alloy under different deformation condition was investigated by SEM, EBSD and OM. The critical strain equation and the dynamic recrystallization kinetics model were obtained. The results showed that the dynamic recrystallization volume fraction increased with the increasing of the strain.The twin dynamic recrystallization (TDRX) was the mainly DRX mechanism at 350°C;the dynamiac recrysallization mechanism was dominated by continuous dynamic recrystallization (CDRX) at 400°C and 450°C. At higher temperature (500°C), the dynamic recrystallization was dominated by discontinuous dynamic recrystallization (DDRX) with a small amount of CDRX.

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Effects of Repetitive Upsetting Extrusion on the Microstructure and Texture of GWZK124 Alloy under Different Starting Temperatures

Materials ◽

10.3390/ma12152437 ◽

2019 ◽

Vol 12 (15) ◽

pp. 2437

Author(s):

Guanshi Zhang ◽

Zhimin Zhang ◽

Yingze Meng ◽

Zhaoming Yan ◽

Xin Che ◽

...

Keyword(s):

Grain Size ◽

Dynamic Recrystallization ◽

Grain Refinement ◽

Volume Fraction ◽

Bimodal Microstructure ◽

Continuous Dynamic Recrystallization ◽

Average Grain Size ◽

Second Phases ◽

Continuous Dynamic ◽

Weak Texture

The effects of repetitive upsetting extrusion under different starting temperatures on the microstructure and texture of GWZK124 alloy were investigated. The results clearly showed that the particles and second phases induced dynamic recrystallization (DRX), which can be explained by the particle-stimulated nucleation (PSN) mechanism. It was shown that grain refinement during repetitive upsetting extrusion (RUE) is dominated by a complicated combination of continuous dynamic recrystallization and discontinuous dynamic recrystallization. The RUEed alloys under different starting temperatures exhibited a bimodal microstructure comprising fine DRXed grains with weak texture and coarse deformed grains with strong texture. The DRXed grains could weaken the texture. As the RUE starting temperature decreased, the average grain size increased and the volume fraction of DRXed grains decreased.

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Microstructure and Texture Evolution of Mg–Gd–Y–Zn–Zr Alloy by Compression–Torsion Deformation

Materials ◽

10.3390/ma12172773 ◽

2019 ◽

Vol 12 (17) ◽

pp. 2773 ◽

Cited By ~ 1

Author(s):

Ping Xu ◽

Jianmin Yu ◽

Zhimin Zhang

Keyword(s):

Dynamic Recrystallization ◽

Strain Rate ◽

Texture Evolution ◽

Continuous Dynamic Recrystallization ◽

Recrystallization Mechanism ◽

Torsion Unit ◽

Continuous Dynamic ◽

Gleeble 3500 ◽

Torsion Deformation ◽

Zr Alloy

Mg–13Gd–4Y–2Zn–0.5Zr alloy was subjected to compression–torsion deformation at 450 °C with a strain rate of 0.001–0.5 s−1 using a Gleeble 3500 torsion unit. The effects of compression–torsion deformation on the microstructure and texture were studied, and the results showed that with the decrease of strain rate, the texture strength decreased, the number of dynamic precipitated particles increased, the degree of recrystallization increased, and the dynamic recrystallization mechanism changed from a continuous dynamic recrystallization mechanism to a continuous and discontinuous dynamic recrystallization mechanism. Along the direction of increasing radius, the degree of dynamic recrystallized grain (DRX) increased, the number of dynamic precipitated particles increased, and the texture strength slightly increased.

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Deformation Behavior and Dynamic Recrystallization of Hot Deformed GH625 Superalloy

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.146-147.798 ◽

2010 ◽

Vol 146-147 ◽

pp. 798-804

Author(s):

Qing Miao Guo ◽

De Fu Li ◽

Sheng Li Guo

Keyword(s):

Dynamic Recrystallization ◽

Deformation Temperature ◽

Volume Fraction ◽

Optical Microscope ◽

Strain Rates ◽

Compression Tests ◽

Continuous Dynamic Recrystallization ◽

Transmission Electron ◽

Lower Strain ◽

Continuous Dynamic

Microstructure evolution during dynamic recrystallization (DRX) of hot deformed GH625 superalloy was investigated by optical microscope (OP) and transmission electron microscope (TEM). Hot compression tests were conducted using Gleeble-1500 simulator. It was found that the nucleation mechanism of DRX for the alloy deformed at 1150°C is composed of discontinuous dynamic recrystallization (DDRX) and continuous dynamic recrystallization (CDRX) in the vicinity of the serrated grain boundaries. With the increasing strain, the fraction of the DRX grains increases, while the size of the DRX grains almost remains in the same range. As the deformation temperature increasing, the size and fraction of the DRX grains increase, and no precipitation of intergranular carbides are found when the deformation temperature increases to 1150°C. At lower strain rate, the size and volume fraction of DRX grains decrease with the increasing strain rates. However, the size and volume fraction of DRX grains increase at higher strain rates due to the deformation thermal effect.

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A novel simulation of continuous dynamic recrystallization process for 2219 aluminium alloy using cellular automata technique

Materials Science and Engineering A ◽

10.1016/j.msea.2021.141256 ◽

2021 ◽

Vol 815 ◽

pp. 141256

Author(s):

Lei Liu ◽

Yunxin Wu ◽

Abdulrahaman Shuaibu Ahmad

Keyword(s):

Cellular Automata ◽

Dynamic Recrystallization ◽

Aluminium Alloy ◽

Recrystallization Process ◽

Continuous Dynamic Recrystallization ◽

Continuous Dynamic

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Determination of the dynamic recrystallization kinetics model for SCM435 steel

Journal of Wuhan University of Technology-Mater Sci Ed ◽

10.1007/s11595-013-0775-5 ◽

2013 ◽

Vol 28 (4) ◽

pp. 819-824 ◽

Cited By ~ 13

Author(s):

Dong Xu ◽

Miaoyong Zhu ◽

Zhengyou Tang ◽

Chao Sun

Keyword(s):

Dynamic Recrystallization ◽

Kinetics Model ◽

Recrystallization Kinetics ◽

Scm435 Steel

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Numerical Modeling of Continuous Dynamic Recrystallization in Sn-Based Solder Connection Under Cyclic Loading

10.1115/ipack2021-73319 ◽

2021 ◽

Author(s):

Marta Kuczynska ◽

Ulrich Becker ◽

Youssef Maniar ◽

Steffen Weihe

Keyword(s):

Grain Size ◽

Dynamic Recrystallization ◽

Cyclic Load ◽

Fe Simulation ◽

Operation Time ◽

Inelastic Strain ◽

Parameter Study ◽

Continuous Dynamic Recrystallization ◽

Gradual Evolution ◽

Continuous Dynamic

Abstract The reoccurring cyclic load imposed onto soldered electronic components during their operation time leads to accumulation of inelastic strains in the structure. On a microscale level, the degree of plastic deformation is determined by the formation and annihilation of dislocations, leading to continuous refinement by creation of new grain boundaries, precipitates relocation and growth. This microstructure rearrangement, triggered by an increasing amount of inelastic deformation, is defined as dynamic recrystallization. This work presents a macroscale modelling approach for the description of continuous dynamic recrystallization observed in Sn-based solder connections. The model used in this work describes kinetics of macroscopic gradual evolution of equivalent grain size, where the initial grain size is continuously refined with increasing accumulated inelastic strain until a saturation grain size is reached. The rate and distribution of dynamic recrystallization is further numerically modelled dependent on the effective accumulated inelastic strain and governing stress multiaxiality. A parameter study of the presented model and its employment in finite element (FE) simulation is further described. Finally, FE simulation of the grain size evolution is demonstrated on an example of a bulky sample under isothermal cyclic mechanical loading, as well as a BGA-like structure under tensile, shear and mixed mode cyclic load.

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