Simultaneously improved mechanical properties and corrosion resistance of Mg-Li-Al alloy produced by severe plastic deformation

Micro-nanostructured materials have superior mechanical properties compared with coarse-grained materials. Severe plastic deformation (SPD) can effectively refine grains, resulting in the formation of typical micro-nanostructures. Fine grains improve alloy strength and toughness. This review summarizes the application of several typical SPD methods for high-Mg Al alloy. The effects of different SPD methods on the microstructure evolution, micro-nanostructure formation mechanism, and mechanical properties of the high-Mg Al alloy are analyzed in sequence. Finally, the development and future of the high-Mg Al alloy micro/nanostructure regulation are described.

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Equal Channel Angular Pressing of Al Alloy AA2219

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.67.53 ◽

2009 ◽

Vol 67 ◽

pp. 53-58

Author(s):

V. Anil Kumar ◽

M.K. Karthikeyan ◽

Rohit Kumar Gupta ◽

P. Ramkumar ◽

P.P. Sinha

Keyword(s):

Mechanical Properties ◽

Plastic Deformation ◽

Severe Plastic Deformation ◽

Grain Refinement ◽

Equal Channel Angular Pressing ◽

High Strength ◽

Dark Field ◽

Grain Structure ◽

Al Alloy ◽

Angular Pressing

Severe plastic deformation processes (SPD) are gaining importance as advanced materials processing techniques and hold immense potential in obtaining ultra fine-grained high strength materials. Among the SPD techniques, Equal channel angular pressing (ECAP) has its own merits to produce materials with ultra fine grains in bulk with better mechanical properties. The material deforms with high level of plastic strain inside the channel resulting in grain refinement of the output material with improvement in mechanical properties. A very viable die configuration was conceptualized and die was made with 1200 channel angle. Processing of 25 mm dia. of Al alloy AA2219 at room temperature was successfully carried out and grain refinement was observed. The mechanism of grain refinement has been studied using optical and transmission electron microscopy (TEM). It was observed that low energy dislocation structure (LEDS) forms concurrently with sub-grain structure due to dislocation rearrangements, which provide stability to the evolving sub-grain structure. Dislocation mobility is hindered by the presence of precipitates and / or intermetallic dispersoids present in the matrix and results in presence of dislocations in grain interiors. The pile up of dislocations at intermetallic dispersoids was confirmed from the dark field TEM micrographs. Present paper describes the experimental procedure and followed to attain severe plastic deformation through ECAP. Increase in hardness as well as refinement in the grain size after 5-passes have been discussed in light of extensive optical and TEM. The mechanisms of grain refinement to achieve nano-grained structure and strengthening accrued from the grain refinement through ECAP has been discussed.

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Effects of Severe Plastic Deformation on Mechanical Properties and Corrosion Behavior of Magnesium Alloys

Magnesium Technology 2018 - The Minerals, Metals & Materials Series ◽

10.1007/978-3-319-72332-7_57 ◽

2018 ◽

pp. 369-371 ◽

Cited By ~ 2

Author(s):

Ahmad Bahmani ◽

Kwang Seon Shin

Keyword(s):

Mechanical Properties ◽

Plastic Deformation ◽

Severe Plastic Deformation ◽

Magnesium Alloys ◽

Corrosion Behavior ◽

Mechanical Properties And Corrosion

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Enhancing mechanical properties and corrosion resistance of a high strength 7A99 Al alloy by introducing pre-rolling in solution and aging treatments

Journal of Alloys and Compounds ◽

10.1016/j.jallcom.2021.162972 ◽

2021 ◽

pp. 162972

Author(s):

Liang Chen ◽

Yuzhu Hou ◽

Zhigang Li ◽

Guoqun Zhao ◽

Cunsheng Zhang

Keyword(s):

Mechanical Properties ◽

Corrosion Resistance ◽

High Strength ◽

Al Alloy ◽

Mechanical Properties And Corrosion

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Structure, Mechanical Properties and Corrosion Resistance of MgCa5 and MgCa5Zn1 Alloys after Plastic Deformation

Solid State Phenomena ◽

10.4028/www.scientific.net/ssp.275.124 ◽

2018 ◽

Vol 275 ◽

pp. 124-133

Author(s):

Ryszard Nowosielski ◽

Agnieszka Gawlas-Mucha ◽

Rafał Babilas

Keyword(s):

Mechanical Properties ◽

Plastic Deformation ◽

Corrosion Resistance ◽

Cast State ◽

Positive Direction ◽

A Value ◽

Surgical Implants ◽

Zn Addition ◽

Mechanical Properties And Corrosion ◽

Extrusion Method

Binary Mg-Ca and ternary Mg-Ca-Zn alloys are a new group of magnesium materials, which can be used in many goods. Among others, biomedical applications of these alloys mainly involved surgical implants in the form of plates or screws. In order to improve mechanical properties and corrosion resistance of Mg-based alloys with Ca and Zn addition in as-cast state a plastic deformation was applied by using the KOBO extrusion method. The microstructure studies conducted by scanning microscopy show that the structure of the alloys after the plastic deformation exhibits banding character and the bands are oriented in the direction of an extrusion. A significant increase of mechanical properties was observed for MgCa5Zn1 alloy. After the plastic deformation, the corrosion potential determined for the MgCa5 and MgCa5Zn1 alloy is shifted into the positive direction, which may suggest the increase of corrosion resistance. Moreover, the MgCa5 alloy in as-cast state was completely dissolved after 288 h of immersion in Ringer’s solution. A volume of hydrogen evolution for the same alloy after plastic deformation showed a value of 35 ml/cm2.

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