Mechanical Properties and Grain Refinement of Al-Mg Alloy by Multi-axial Alternative Warm Forging

In this investigation, aluminium Al-2.5% Mg cast alloy was modified by adding 0.5 Ti and 0.1 B wt % modifiers to investigate their impact on the dynamic behaviour, as well as the mechanical and microstructure properties. The dynamic properties were analysed experimentally using a free vibration impact test and predicted using finite element methods. This study used a high-resolution polarised optical microscope to analyse the microstructure of the studied alloys and X-ray Powder Diffraction (XRD) analysis to determine the developed phases. Microstructure and mechanical properties were mostly enhanced as a result of grain refining during solidification and through the metal segregation process. The microstructure analysis of the modified alloy showed a significant improvement in the grain refinement; hence, the grains were 10 times finer than the cast alloy. The modified Al-2.5% Mg/Ti-B alloy demonstrated reduced inter-granular corrosion (IGC) than the Al-2.5% Mg standard cast alloy. By incorporating Ti-B modifiers into the composition of the cast Al-Mg alloy, the ultimate tensile strength (UTS), strain (ε), and hardness values (HV) were increased by 30.5%, 100%, and 18.18%, respectively. The dynamic properties of the modified alloy showed an enhancement in the resonant (fn) and damping ratio (ζ) by 7% and 68%, respectively. The predicted resonance frequencies of the investigated alloys showed results close to the experimental dynamic tests.

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Mechanical Properties and Texture Evolution of AZ31 Mg Alloy during Equal Channel Angular Pressing

Materials Science Forum ◽

10.4028/www.scientific.net/msf.475-479.545 ◽

2005 ◽

Vol 475-479 ◽

pp. 545-548 ◽

Cited By ~ 4

Author(s):

Hyo Tae Jeong ◽

Woo Jin Kim

Keyword(s):

Mechanical Properties ◽

Grain Refinement ◽

Equal Channel Angular Pressing ◽

Texture Evolution ◽

Fiber Texture ◽

Mg Alloy ◽

Angular Pressing ◽

Ecap Process ◽

Az31 Mg Alloy ◽

Similar Texture

Microstructure and texture evolution in the AZ31 Mg alloy subject to equal channel angular pressing (ECAP) have been investigated and correlated with the mechanical properties. When AZ31 Mg alloy was ECAPed up to 8 passes following the route Bc, grain refinement occurred effectively. Texture was also changed during ECAP. The original fiber texture of the extruded AZ31 Mg alloy changed to a new texture component of ] 1 3 2 5 )[ 1 1 01 ( , and the texture of ] 1 3 2 5 )[ 1 1 01 ( orientation was rotated to ] 0 2 5 7 )[ 6 4 13 ( orientation after 6-pass ECAP process. The variation of the strength with the pass number was explained by the texture and grain size. The strength data of AZ31 Mg alloys followed the standard Hall-Petch relationship when the similar texture was retained during the ECAP process. Otherwise the effect of texture on strength was dominant over the strengthening due to grain refinement.

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Mg/ZrO2 Metal Matrix Nanocomposites Fabricated by Friction Stir Processing: Microstructure, Mechanical Properties, and Corrosion Behavior

Frontiers in Bioengineering and Biotechnology ◽

10.3389/fbioe.2021.605171 ◽

2021 ◽

Vol 9 ◽

Author(s):

Ke Qiao ◽

Ting Zhang ◽

Kuaishe Wang ◽

Shengnan Yuan ◽

Shengyi Zhang ◽

...

Keyword(s):

Mechanical Properties ◽

Electron Microscope ◽

Grain Refinement ◽

Friction Stir Processing ◽

Biological Properties ◽

Mg Alloy ◽

Corrosion Properties ◽

Metal Matrix Nanocomposites ◽

Friction Stir ◽

Average Grain Size

Magnesium (Mg) and its alloys have attached more and more attention because of their potential as a new type of biodegradable metal materials. In this work, AZ31/ZrO2 nanocomposites with good uniformity were prepared successfully by friction stir processing (FSP). The scanning electron microscope (SEM) and transmission electron microscope (TEM) were used to characterize the microstructure of the composites. The mechanical properties, electrochemical corrosion properties and biological properties were evaluated. In addition, the effect of reinforced particles (ZrO2) on the microstructure and properties of the composite was studied comparing with FSP AZ31 Mg alloy. The results show that compared with the base metal (BM), the AZ31/ZrO2 composite material achieves homogenization, densification, and grain refinement after FSP. The combination of dynamic recrystallization and ZrO2 particles leads to grain refinement of Mg alloy, and the average grain size of AZ31/ZrO2 composites is 3.2 μm. After FSP, the c-axis of grain is deflected under the compression stress of shoulder and the shear stress of pin. The ultimate tensile strength (UTS) and yield strength (YS) of BM were 283 and 137 MPa, respectively, the UTS and YS of AZ31/ZrO2 composites were 427 and 217 MPa, respectively. The grain refinement and Orowan strengthening are the major strengthening mechanisms. Moreover, the corrosion resistance in simulated body fluid of Mg alloy is improved by grain refinement and the barrier effect of ZrO2.

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Analysing the combined effect of crystallographic orientation and grain refinement on mechanical properties and corrosion behaviour of ECAPed ZE41 Mg alloy

Journal of Magnesium and Alloys ◽

10.1016/j.jma.2020.08.015 ◽

2020 ◽

Vol 8 (4) ◽

pp. 1128-1143

Author(s):

S. Prithivirajan ◽

S. Narendranath ◽

Vijay Desai

Keyword(s):

Mechanical Properties ◽

Grain Refinement ◽

Crystallographic Orientation ◽

Corrosion Behaviour ◽

Combined Effect ◽

Mg Alloy ◽

Mechanical Properties And Corrosion

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Grain refinement and mechanical properties improvement of AZ31 Mg alloy sheet obtained by two - stage rolling

Materials Science and Engineering A ◽

10.1016/j.msea.2017.02.107 ◽

2017 ◽

Vol 691 ◽

pp. 81-87 ◽

Cited By ~ 21

Author(s):

Ru Ma ◽

Yiquan Zhao ◽

Yinong Wang

Keyword(s):

Mechanical Properties ◽

Grain Refinement ◽

Alloy Sheet ◽

Mg Alloy ◽

Two Stage ◽

Az31 Mg Alloy

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Microstructures and Mechanical Properties of Mg Alloy after Severe Torsion Straining Process

Materials Science Forum ◽

10.4028/www.scientific.net/msf.503-504.949 ◽

2006 ◽

Vol 503-504 ◽

pp. 949-954 ◽

Cited By ~ 9

Author(s):

Yuichi Miyahara ◽

N. Emi ◽

Koji Neishi ◽

Katsuaki Nakamura ◽

Kenji Kaneko ◽

...

Keyword(s):

Mechanical Properties ◽

Plastic Deformation ◽

Grain Refinement ◽

Room Temperature ◽

Rotation Speed ◽

Continuous Process ◽

Mg Alloy ◽

Compression Tests ◽

Moving Speed ◽

Az61 Mg Alloy

Grain refinement is attempted using severe plastic deformation (SPD) through the severe torsion straining process (STSP) which we have developed recently. The STSP is a continuous process for grain refinement without requirement of any die. In this study, an AZ61 Mg alloy was subjected to STSP at a temperature of 573 K with a rotation speed of 10 rpm and a moving speed of 200 mm/min. With this process, an initial grain size of ~20 μm was reduced to ~2~3 μm. Room temperature compression tests revealed that there were no cracks after 15% of compression for the STSP sample whereas fracture occurred for a conventionally extruded sample. For compression tests at 473 K, no cracks occurred in the STSP samples after 80% compression but compression was feasible without cracking only up to 20% for an extruded sample. It is shown that the STSP can be useful for grain refinement and ductility improvement of the AZ61 Mg alloy.

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