Influence of Coarse Mg3Bi2 Particles on Deformation Behaviors of Mg-Bi Alloys

Mg-Bi binary alloys with concentrations of 1, 3, 6, and 9 wt% Bi and ternary Mg-9Bi-2.5Zn alloy were prepared by casting and hot extrusion. The results show that alloying with Bi refined as-cast grains of Mg alloys and the refinement efficiency of Bi is in between Al and Zr. It was also found that a critical value for the area fraction of constituent Mg3Bi2 particles seems to appear, which influences the dynamic recrystallization mechanism during extrusion. This influence results in either uniform or heterogenetic distribution of grain size and different extrusion texture intensities. Furthermore, the addition of Zn affected both the grain size and the area fraction/size of Mg3Bi2. Mechanical results and microstructure/fractography observation suggest that Mg3Bi2 particles do not impact the tensile nor compression yielding stress but act as fracture sources.

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Dynamic Recrystallization during Hot Extrusion in AZ31 and AZ80 Alloys

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.26-28.449 ◽

2007 ◽

Vol 26-28 ◽

pp. 449-452 ◽

Cited By ~ 2

Author(s):

M. Honda ◽

Tokuteru Uesugi ◽

Yorinobu Takigawa ◽

Hiroshi Mabuchi ◽

Kenji Higashi

Keyword(s):

Grain Size ◽

Dynamic Recrystallization ◽

Optical Microscopy ◽

Hot Extrusion ◽

Mg Alloys ◽

Recrystallization Behavior ◽

Hollomon Parameter ◽

Dynamic Recrystallization Behavior ◽

Recrystallized Grain Size

Dynamic recrystallization behavior that occurs during the hot extrusion was examined in two commercial Mg alloys, AZ31 and AZ80 alloys. The initial grain size, d0, and the dynamically recrystallized grain size, drec, after the extrusion was investigated using optical microscopy. The dynamically recrystallized grain size decreased with an increasing the Zener-Hollomon parameter.

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Effects of Extrusion Ratio on Microstructures and Properties of Al-Cu-Mg-Ag-Ce-Er Alloy Wires

Materials Science Forum ◽

10.4028/www.scientific.net/msf.898.191 ◽

2017 ◽

Vol 898 ◽

pp. 191-198

Author(s):

Yu Peng Xu ◽

Ze Sheng Ji

Keyword(s):

Grain Size ◽

Tensile Strength ◽

Dynamic Recrystallization ◽

Hot Extrusion ◽

Nucleation Mechanism ◽

Extrusion Ratio ◽

Average Grain Size ◽

Second Phases ◽

Grain Coalescence

The Al-Cu-Mg-Ag-Ce-Er alloy wires with different extrusion ratio (λ=12, 25, 50, 100) were produced by hot extrusion at 450oC. The effects of extrusion ratio on the microstructures, tensile strength and elongation of Al-Cu-Mg-Ag-Ce-Er alloy wires were researched by means of OM, SEM, TEM and mechanical test.The results show that with the extrusion ratio increasing, the average grain size decreased from 83μm to 42μm, the Al2Cu, Al8Cu4Ce and Al8Cu4Er phases was broken gradually, and the homogeneousdistribution about these second-phases in the alloy wires increased. The tensile strength increased from 366MPa to 459MPa with extrusion ratio, and the elongation initially decreased and then increased with the increase of extrusion ratio. Dynamic recrystallization for Al-Cu-Mg-Ag-Ce-Er alloy occurred at different extrusion ratios. Withincreasing of extrusion ratio, the main nucleation mechanism of dynamic recrystallization changed from the sub-grain coalescence at lower extrusion ratioto the acceleration of second-phases for nucleation at higher extrusion ratio.

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Dynamic Recrystallization during Hot Extrusion in Mg-3Al-0.1Y Alloy

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.26-28.433 ◽

2007 ◽

Vol 26-28 ◽

pp. 433-436 ◽

Cited By ~ 1

Author(s):

T. Noro ◽

Tokuteru Uesugi ◽

Yorinobu Takigawa ◽

Masato Tsujikawa ◽

Hiroshi Mabuchi ◽

...

Keyword(s):

Grain Size ◽

Dynamic Recrystallization ◽

Hot Extrusion ◽

Al Alloys ◽

Recrystallization Behavior ◽

Hollomon Parameter ◽

Fine Microstructure ◽

Dynamic Recrystallization Behavior ◽

Recrystallized Grain Size ◽

The Relationship

Dynamic recrystallization behavior of Mg-3.1wt.%Al-0.1wt.%Y alloy was investigated. During extrusion, dynamic recrystallization occurred and very fine microstructure was obtained. We compared the relationship between Zener-Hollomon parameter, Z, and the dynamically recrystallized grain size, drec, and between the normalized recrystallized grain size, drec/d0, where d0 is the initial grain size, and Z for Mg-3.1wt. %Al-0.1wt.%Y with commercial Mg-3Al-0.5Zn alloy. As the result, the dynamically recrystallized grain size of Mg-3Al-0.1Y was finer than that of Mg-3Al-0.5Zn alloy under the equivalent Z, while the initial grain size of Mg-3Al-0.1Y was coarser than Mg-3Al-0.5Zn alloy. The normalized grain size for Mg-3Al-0.1Y alloy was much smaller than that of Mg-3Al-0.5Zn alloy under the equivalent Z. We conclude that small addition of Y to Mg-Al alloys is effective for grain refinement by dynamic recrystallization.

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Effect of Si Content on Dynamic Recrystallization of Al–Si–Mg Alloys During Hot Extrusion

Journal of Material Science and Technology ◽

10.1016/j.jmst.2014.07.011 ◽

2014 ◽

Vol 30 (12) ◽

pp. 1271-1277 ◽

Cited By ~ 17

Author(s):

Yuna Wu ◽

Hengcheng Liao ◽

Jian Yang ◽

Kexin Zhou

Keyword(s):

Dynamic Recrystallization ◽

Hot Extrusion ◽

Mg Alloys ◽

Si Content

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Modeling of Static and Geometric Dynamic Recrystallization during Hot Extrusion of Al-Mg-Si Alloy

Materials Science Forum ◽

10.4028/www.scientific.net/msf.794-796.728 ◽

2014 ◽

Vol 794-796 ◽

pp. 728-733

Author(s):

Pavel Sherstnev ◽

Adrian Zamani

Keyword(s):

Grain Size ◽

Dynamic Recrystallization ◽

Strain Rate ◽

Surface Current ◽

Hot Extrusion ◽

Processing Conditions ◽

State Variables ◽

Size Evolution ◽

Recrystallized Grain Size ◽

Deform 2D

Under certain conditions of extrusion temperature and strain rate Al-Mg-Si alloys produce coarse recrystallized grains at and near the surface. Current FEM models are able to analyze grain size evolution for extruded profiles, but cannot predict the coarse recrystallized grains near the surface. A new model using DEFORM 2D and local state variables such as strain, strain rate and temperature is compared with Al-Mg-Si rods extruded at 440°C and 500°C for two extremes of strain rate. The model is found to be sensitive to the processing conditions and to accurately predict the recrystallized grain size and fraction.

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Variation in Deformation Behaviors Along the Transverse Direction During the Warm Rolling of a 1480-mm-Wide AZ31B Plate

Chinese Journal of Mechanical Engineering ◽

10.1186/s10033-021-00608-w ◽

2021 ◽

Vol 34 (1) ◽

Author(s):

Chenchen Zhi ◽

Lifeng Ma ◽

Weitao Jia ◽

Pengtao Liu ◽

Qichi Le ◽

...

Keyword(s):

Grain Size ◽

Magnesium Alloy ◽

Dynamic Recrystallization ◽

Transverse Direction ◽

Thick Plate ◽

Warm Rolling ◽

Rolled Plate ◽

Average Grain Size ◽

Width Direction ◽

Deformation Behaviors

AbstractA decrease in the weight of aerospace vehicles, large ships, weapons, and high-speed trains will increase the demand for wide-width magnesium alloy plates and their composite parts to replace steel and plastic. An investigation was conducted to study the variation in deformation behaviors along the transverse direction during the warm rolling of a 1480-mm-wide AZ31B plate. A uniaxial thermal compression test with a 59 % reduction was performed at different positions on a 13.7-mm-thick rolled plate along the width direction at a temperature of 220 °C and 270 °C and strain rate of 15 s−1. At the same time, the 13.7-mm-thick plate was rolled in a single pass to 5.6 mm on a mill with a 1725-mm-wide roll to confirm the thermal deformation behavior and the dynamic recrystallization (DRX). The results show that the main texture type does not change and the grain size does not have a clear deflection when the magnesium alloy plate reaches a certain value under rolling accumulative reduction. The grain size of a 13.7-mm-thick plate increases with a decrease in the distance to the center layer in the thickness direction. In the width direction, the edge (R6) first decreases and then increases toward the symmetric plane (R1). The critical stress required for dynamic recrystallization in the transition zone R3 of the rolled plate width is minimum, and the average grain size is minimum owing to the relatively complete recrystallization.

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The Dynamic Recrystallization Model of 7050 Al-Alloy during Hot Deformation

Materials Science Forum ◽

10.4028/www.scientific.net/msf.749.274 ◽

2013 ◽

Vol 749 ◽

pp. 274-281

Author(s):

Zhi Hao Zhang ◽

Wen Rong Hou ◽

Qing Hai Pang ◽

Jian Xin Xie

Keyword(s):

Grain Size ◽

Dynamic Recrystallization ◽

Relative Error ◽

Hot Deformation ◽

Hot Extrusion ◽

Hot Compression ◽

Model Parameters ◽

Al Alloy ◽

Maximum Relative Error ◽

Compression Stress

In this paper, the compression stress-strain curves of 7050 Al-alloy under various deformation conditions were obtained, and the recrystallization structures were analyzed. The main parameters of dynamic recrystallization model were determined. The rationality of the model parameters were verified by hot compression and extrusion. The results show that the accuracy of the model is high enough for predicting the recrystallization of the 7050 Al-alloy during hot deformation. Comparison of the experiment and calculated results in hot compression shows that the maximum relative error of the recrystallization fraction is 11.4%. Comparison of the experiment and calculated results in hot extrusion shows that the maximum relative error of the recrystallization fraction is 13.0%, and that of the recrystallization grain size is 14.9%.

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