Microstructure Evolution of ZK60M Twin-Roll-Casted Magnesium Alloy during Hot Compression and Annealing

2011 ◽  
Vol 284-286 ◽  
pp. 1502-1505 ◽  
Author(s):  
Ru Ma ◽  
Shou Ren Wang ◽  
Yong Wang ◽  
Li Ying Yang
Keyword(s):  
Magnesium Alloy ◽  
Annealing Temperature ◽  
Static Recrystallization ◽  
Shear Bands ◽  
Structural Evolution ◽  
Electron Back Scatter Diffraction ◽  
Hot Compression ◽  
Ebsd Data ◽  
Different Temperatures ◽  
Twin Roll

The effects of hot compression deformation (300°C/0.1s-1) and annealing on the microstructural evolution of ZK60+0.8Zn (ZK60M) alloys were investigated in the present works. Lots of sub-structures were studded in the shear bands under the deformed conditions, and after annealing, the sub-structures in the shear bands occurred static recrystallization following by the growth of recrystallized grains. With the increase of annealing temperature, amounts of twins decrease while static recrystallization (SRX) grains increase while dislocations rearrange forming sub-grains ultimately induced static recrystallization. And that, the micro structural evolution and grain boundary distribution of the specimen as-deformed and as-annealed at different temperatures were analyzed by electron back scatter diffraction (EBSD) data.

scholarly journals Effect of Shear Bands Induced by Asymmetric Rolling on Microstructure and Texture Evolution of Non-Oriented 3.3% Si Steel

Materials ◽  
2020 ◽  
Vol 13 (21) ◽  
pp. 4696
Author(s):  
Zhiyong Fang ◽  
Yanhui Guo ◽  
Bin Fu ◽  
Liqun Wei ◽  
Jun Chen ◽  
...  
Keyword(s):  
Surface Layer ◽  
Thermal Energy ◽  
Annealing Temperature ◽  
Texture Evolution ◽  
Shear Bands ◽  
Subsequent Annealing ◽  
Asymmetric Rolling ◽  
Nucleation Sites ◽  
Different Temperatures ◽  
Complete Recrystallization

In the present work, the microstructure and texture of non-oriented 3.3% Si steel processed by asymmetric rolling (ASR) and subsequent annealing at different temperatures were compared with those obtained when using traditional symmetric rolling (SR). This work aims to reveal the effect of shear bands introduced by the ASR on the microstructure and texture evolution. The ASR sample reaches a recrystallization fraction of 62% at an annealing temperature of 650 °C, which is 32% higher than that of the SR sample annealed at the same temperature. This can be attributed to the abundant shear bands introduced by the ASR, which serve as the heterogeneous nucleation sites for the recrystallized grains. When increasing the annealing temperature to 750 °C, complete recrystallization could be observed in both asymmetric- and symmetric-rolled samples. When using an annealing temperature of 650 °C, the γ-oriented grains were dominant in the surface layer, while strong Goss-oriented grains could be observed in the center in the ASR sample. This is due to the fragmented small subgrains with different orientations in the surface layer inhibiting the nucleation of Goss- and cube-oriented grains during the annealing. In contrast, numerous Goss- and cube-oriented grains were formed in the surface layer after complete recrystallization when the ASR sample was annealed at a temperature of 750 °C. This may be related to the higher thermal energy, which benefits the nucleation of the Goss- and cube-oriented grains. In addition, ASR significantly increased the strength of η-fiber after complete recrystallization when compared with SR. This work might be helpful to design the rolling and the subsequent annealing processes.

MICROSTRUCTURAL EVOLUTION AND FLOW BEHAVIOR OF TWIN-ROLL CAST AZ41 MAGNESIUM ALLOY DURING HOT COMPRESSION

2012 ◽  
Vol 26 (32) ◽  
pp. 1250181
Author(s):  
ZHIYI LIU ◽  
XU CHEN ◽  
YANHUI HOU ◽  
SUKBONG KANG
Keyword(s):  
Elevated Temperature ◽  
Magnesium Alloy ◽  
Dynamic Recrystallization ◽  
Strain Rate ◽  
Microstructural Evolution ◽  
Flow Behavior ◽  
Hot Compression ◽  
Dislocation Slip ◽  
Twin Roll Cast ◽  
Twin Roll

Microstructural evolution and flow behavior of twin-roll cast AZ41 magnesium alloy during hot compression were characterized by employing deformation temperature of 300°C, 350°C and 400°C, and strain rate ranging from 10-3 to 10-2 s -1. When compressed at different temperature (300°C, 350°C and 400°C) and strain rate (10-3 and 10-2 s -1) all stress strain curves showed a flow softening behavior before strained to 0.51 due to dynamic recrystallization, even though concurrent twinning was quite active. Twinning contributed to the flow hardening behavior appeared during the end of hot compression (ε > 0.51) at a strain rate of 10-2 s -1 and elevated temperature (300°C, 350°C and 400°C) in spite of the softening effect of concurrently occurred dynamic recrystallization. TEM image showed that discontinuous recrystallization occurred when deformed at elevated temperature as high as 400°C and the strain rate ranging from 10-2 to 10-3 s -1. It is suggested that dislocation slip, twinning and recrystallization develop in a cyclic mode from initial stage to the end of hot compression.

Microstructure and hot compression behavior of twin-roll-casting AZ41M magnesium alloy

Rare Metals ◽  
2010 ◽  
Vol 29 (4) ◽  
pp. 396-400 ◽  
Author(s):  
Shouren Wang ◽  
Min Wang ◽  
Ru Ma ◽  
Yong Wang ◽  
Yanjun Wang
Keyword(s):  
Magnesium Alloy ◽  
Hot Compression ◽  
Compression Behavior ◽  
Twin Roll Casting ◽  
Roll Casting ◽  
Twin Roll

Structural Evolution on the Cross-Section of an AZ31 Magnesium Alloy Processed by High-Pressure Torsion

2010 ◽  
Vol 667-669 ◽  
pp. 247-252 ◽  
Author(s):  
Roberto B. Figueiredo ◽  
Terence G. Langdon
Keyword(s):  
High Pressure ◽  
Magnesium Alloy ◽  
Cross Section ◽  
High Pressure Torsion ◽  
Shear Bands ◽  
Structural Evolution ◽  
Grain Structure ◽  
Az31 Magnesium Alloy ◽  
Average Grain Size ◽  
The Cross

Disks of an AZ31 magnesium alloy were processed by High-Pressure Torsion (HPT) at 463 K to different numbers of rotations. The grain structure was evaluated along the cross-section of the disks using optical microscopy. Significant heterogeneities in the average grain size were observed in areas of the disks which were located at similar distances to the center but at different distances from the surface. Moreover, different grain structures were observed in neighboring areas and shear bands occurred at several locations in the disks. Microhardness tests revealed differences in the strength of the material as a function of the distance to the surface. An analysis of the grain structure and hardness distribution suggests the occurrence of flow localization in HPT processing.

Influence of Annealing Temperature on Microstructure and Properties of Warm-Rolled AZ31 Magnesium Alloy Sheets

2013 ◽  
Vol 747-748 ◽  
pp. 352-358
Author(s):  
Hua Zhang ◽  
Guang Sheng Huang ◽  
Jin Han Lin ◽  
Li Fei Wang
Keyword(s):  
Magnesium Alloy ◽  
Strain Hardening ◽  
Annealing Temperature ◽  
Az31 Alloy ◽  
Az31 Magnesium Alloy ◽  
Strain Hardening Exponent ◽  
N Value ◽  
Microstructure And Properties ◽  
Different Temperatures ◽  
R Value

Warm-rolled AZ31 alloy sheets were annealed at different temperatures ranging from 150 to 450°C. Effects of annealing temperature on microstructure and properties of warm-rolled AZ31 alloy sheets, especially the formability, were investigated. The results revealed that the Lankford value (r-value) and strain-hardening exponent (n-value) first increased and then became relatively steady with the increase of annealing temperature. The Erichsen value (IE) first increased and then decreased with the increase of annealing temperature and the AZ31 alloy sheets exhibited the highest IE of 3.02 mm when annealing at 250°C, which can be mainly attributed to a larger elongation, a lower r-value and a higher n-value.

Static Recrystallization of Magnesium Alloy during TRC-HC Deformation Followed by Annealing

2011 ◽  
Vol 295-297 ◽  
pp. 730-733 ◽  
Author(s):  
Yong Wang ◽  
Shou Ren Wang ◽  
Ru Ma ◽  
Li Ying Yang
Keyword(s):  
Magnesium Alloy ◽  
Grain Boundary ◽  
Static Recrystallization ◽  
Electron Backscatter Diffraction ◽  
Boundary Migration ◽  
Transmission Electron ◽  
Subgrain Rotation ◽  
Twin Roll Cast ◽  
Backscatter Diffraction ◽  
Twin Roll

Using optical microscopy, electron backscatter diffraction and transmission electron microscopy, the static recrystallization (SRX) mechanisms of ZK 60 magnesium alloy was examined under twin-roll-cast and hot compression (TRC-HC, 350 °C/0.1 s-1) and subsequent annealing (1000 second at 250-400°C). The static recrystallization (SRX) mechanisms, such as grain boundary migration (GBM), grain boundary bulging (GLB) and subgrain rotation (SGR), were discussed.

Effect of annealing on fluorescence of Ce3+-doped silica prepared by sol-gel process

2000 ◽  
Vol 15 (11) ◽  
pp. 2364-2367 ◽  
Author(s):  
H. J. Bi ◽  
W. P. Cai ◽  
H. Z. Shi ◽  
L. D. Zhang ◽  
B. D. Yao
Keyword(s):  
Vapor Deposition ◽  
Annealing Temperature ◽  
Sol Gel ◽  
Structural Evolution ◽  
Chemical Vapor ◽  
Emission Peak ◽  
Silica Network ◽  
Oh Groups ◽  
Sol Gel Process ◽  
Different Temperatures

We prepared Ce3+-doped silica by the sol-gel method and studied the effect of annealing on fluorescence of these samples. Different fluorescence was observed for samples annealed at different temperatures, changing gradually from solution like fluorescence to fluorescence similar to that observed in the Ce3+-doped silica prepared by chemical vapor deposition. It was found that the emission intensity first decreased with increasing annealing temperature until 500 °C, and then increased with the temperature ranging from 500 to 950 °C. Meanwhile, the emission peak showed a large red shift and an obvious broadening. These changes were attributed to the annealing-induced structural evolution in silica: Ce3+ ions changed from coordinating with water and terminal OH-groups to embedding in silica network.

Dynamic modeling of twin roll casting AZ41 magnesium alloy during hot compression processing

2010 ◽  
Vol 20 ◽  
pp. s513-s518 ◽  
Author(s):  
Min WANG ◽  
Shou-ren WANG ◽  
S.B. KANG ◽  
J.H. CHO ◽  
Yan-jun WANG
Keyword(s):  
Magnesium Alloy ◽  
Dynamic Modeling ◽  
Hot Compression ◽  
Twin Roll Casting ◽  
Roll Casting ◽  
Twin Roll
Sign in / Sign up

Export Citation Format

Share Document