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AZ31 magnesium alloy tube manufactured by composite forming technology including extruded-shear and bending based on finite element numerical simulation and experiments

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Hongjun Hu
Hongjun Hu
Hongjun Hu
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Xing Hong
Xing Hong
Xing Hong
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Ye Tian
Ye Tian
Ye Tian
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Dingfei Zhang
Dingfei Zhang
Dingfei Zhang
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Abstract and Figures

This paper presents a new forming technology for manufacturing the AZ31 magnesium alloy thin-wall tube. The direct extrusion process and continuous shearing-bending process are combined to produce thin-wall magnesium tube, abbreviated as “TESB” (tube extrusion-shearing-bending). The process has been studied based on the combination of experiments and numerical simulations, and the influences of temperatures, extrusion stresses, and friction factors on the forming process have been studied by Deform-3D simulation. And the mechanical properties and the grain size of the formed product have been tested. TESB technology has been proved to refine the grains of magnesium alloy tube effectively, and the mechanical property of the product can be improved. The better experimental extrusion conditions were also obtained by simulation, and the properties of the products under the condition of lubrication were better when the temperature was 400°C. Three-dimensional finite element modeling is used to investigate the plastic deformation behaviors of wrought magnesium alloy during TESB process. Numerical results indicate TES could increase the cumulative strains effectively by direct extrusion and additional shearings. Experiments show that microstructures of magnesium alloy fabricated by TESB process can be refined to 50% of the original grain size with more uniform distribution. TES process could improve hardness of magnesium alloy obviously by comparing with which fabricated by direct extrusion.
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Vol.:(0123456789)
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The International Journal of Advanced Manufacturing Technology (2021) 115:2395–2402
https://doi.org/10.1007/s00170-021-07242-9
ORIGINAL ARTICLE
AZ31 magnesium alloy tube manufactured bycomposite forming
technology includingextruded-shear andbending based onfinite
element numerical simulation andexperiments
HongjunHu1· XingHong1· YeTian1· DingfeiZhang2
Received: 9 November 2020 / Accepted: 4 May 2021 / Published online: 24 May 2021
© The Author(s), under exclusive licence to Springer-Verlag London Ltd., part of Springer Nature 2021, corrected publication 2023
Abstract
This paper presents a new forming technology for manufacturing the AZ31 magnesium alloy thin-wall tube. The direct extrusion
process and continuous shearing-bending process are combined to produce thin-wall magnesium tube, abbreviated as “TESB” (tube
extrusion-shearing-bending). The process has been studied based on the combination of experiments and numerical simulations,
and the influences of temperatures, extrusion stresses, and friction factors on the forming process have been studied by Deform-3D
simulation. And the mechanical properties and the grain size of the formed product have been tested. TESB technology has been
proved to refine the grains of magnesium alloy tube effectively, and the mechanical property of the product can be improved. The
better experimental extrusion conditions were also obtained by simulation, and the properties of the products under the condition
of lubrication were better when the temperature was 400°C. Three-dimensional finite element modeling is used to investigate the
plastic deformation behaviors of wrought magnesium alloy during TESB process. Numerical results indicate TES could increase
the cumulative strains effectively by direct extrusion and additional shearings. Experiments show that microstructures of magnesium
alloy fabricated by TESB process can be refined to 50% of the original grain size with more uniform distribution. TES process could
improve hardness of magnesium alloy obviously by comparing with which fabricated by direct extrusion.
Keywords AZ31 magnesium alloy· Extrusion· Shearing· Tube· Finite element method· Microstructure· Experiment and
simulation· Grain refinement
1 Introduction
The quality of the magnesium element is about 2.4% of the
total mass of the earth’s crust. In addition, magnesium is also
distributed in seawater, salt lakes, and brine widely, such as
Qinghai Salt Lake, where the reserves of magnesium chloride
are as high as 8 billion tons, which exist in various forms, and
magnesium alloys are inexhaustible metal materials [1–3].
Magnesium alloy, as a “green engineering material in the 21st
century,”, has high specific strength and specific stiffness,
good dimensional stability, thermal conductivity, and strong
vibration resistance; can withstand large impact load; and has
excellent casting, machining performance, and easy recycling.
These characteristics make it occupy a place in the aerospace
field and can be used as aircraft, missiles, spacecrafts, satel-
lites, etc. With the development of science and technology, the
development of aerospace field is more and more inseparable
from the participation of magnesium alloy [4].
In recent years, magnesium alloys are used in transportation,
communication, electronics, and aerospace industries exten-
sively. However, these alloys are difficult to be deformed at room
temperature due to its hexagonal lattice structure with limited
numbers of separate slip systems [5]. Although more than 90%
of the magnesium alloy products are made by casting currently,
large-scale production of wrought magnesium alloy products
may be the future development direction. As comparing with
magnesium alloy productions by casting process, the plastic
deformation process can produce a variety of plates, rods, tubes,
profiles, and forging products, and their strength, ductility and
mechanical properties are higher than those made by casting.
As one of the key forming process, extrusion process is real-
ized by plastic deformation under the action of three direction
* Hongjun Hu
hhj@cqut.edu.cn
1 Materials Science andEngineering College, Chongqing
University ofTechnology, Chongqing400050, China
2 National Engineering Research Center forMagnesium
Alloys, Chongqing400044, China
Content courtesy of Springer Nature, terms of use apply. Rights reserved.
... The generalized coulomb's law was used to explain friction behavior caused by the shear stress and the extrusion force. Shear force between workpiece and die is considered to be caused by friction [15][16][17] shown in Eq. (1). τ is shear stress, σ is equivalent stress. ...
... Examination of the predicted strains provides quantitative insight into deformation behaviors of billets during TC-ECAE process [16][17][18]. It is necessary to understand the distributions and magnitudes of effective stresses during TC-ECAE process. ...
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