Superplastic Deformation of Magnesium Alloys

1992 ◽  
pp. 117-147
Author(s):  
Oscar A. Kaibyshev
Keyword(s):  
Magnesium Alloys ◽  
Superplastic Deformation

scholarly journals Superplastic deformation of fine-grained AE42 and LAE442 magnesium alloys

2018 ◽  
Vol 8 (4) ◽  
pp. 538-542
Author(s):  
P. Minárik ◽  
T. Vávra ◽  
J. Stráský ◽  
B. Hadzima ◽  
R. Král
Keyword(s):  
Magnesium Alloys ◽  
Superplastic Deformation ◽  
Fine Grained

Superplastic deformation mechanism in powder metallurgy magnesium alloys and composites

2001 ◽  
Vol 49 (11) ◽  
pp. 2027-2037 ◽  
Author(s):  
H. Watanabe ◽  
T. Mukai ◽  
M. Mabuchi ◽  
K. Higashi
Keyword(s):  
Powder Metallurgy ◽  
Magnesium Alloys ◽  
Deformation Mechanism ◽  
Superplastic Deformation

Texture Change during Superplastic Deformation in Fine-Grained Magnesium Alloys

2016 ◽  
Vol 838-839 ◽  
pp. 59-65 ◽  
Author(s):  
Hiroyuki Watanabe ◽  
Tokuteru Uesugi ◽  
Yorinobu Takigawa ◽  
Kenji Higashi
Keyword(s):  
Grain Boundary ◽  
Magnesium Alloys ◽  
Superplastic Deformation ◽  
Longitudinal Direction ◽  
Grain Boundary Sliding ◽  
Dislocation Slip ◽  
Grain Rotation ◽  
Fine Grained ◽  
Texture Change ◽  
Boundary Sliding

Texture change during superplastic deformation was examined and compared in two magnesium alloys with different chemical composition. These alloys were extruded to refine the microstructure. The pre-existing basal texture of both alloys became slightly more random within the bulk probably owing to grain boundary sliding and the accompanying grain rotation. However, the texture changes differed between tensile and compressive deformation along the extrusion (longitudinal) direction. This fact suggests that dislocation slip is important in superplastic deformation. It was concluded that dislocation slip acts primarily as an accommodation mechanism for grain boundary sliding.

4D Damage Characterization during Superplastic Deformation of Magnesium Alloys

2012 ◽  
Vol 735 ◽  
pp. 61-66 ◽  
Author(s):  
Pierre Lhuissier ◽  
Mario Scheel ◽  
Luc Salvo ◽  
Elodie Boller ◽  
Marco Di Michiel ◽  
...  
Keyword(s):  
Magnesium Alloys ◽  
Aluminium Alloys ◽  
Superplastic Deformation ◽  
Fracture Process ◽  
High Temperature Deformation ◽  
Temperature Deformation ◽  
Efficient Tool ◽  
X Ray ◽  
Micro Tomography ◽  
Deformation Tests

As for aluminium alloys, magnesium alloys are generally sensitive to strain induced cavitation when they are deformed in superplastic conditions. It has been widely shown that X-ray micro tomography is a particularly efficient tool for studying in 3D damage mechanisms during superplastic deformation. However, such characterisations are generally performed in post mortem conditions, namely on samples first deformed up to given strains and then characterised. In the present investigation, thanks to particularly short acquisition times offered by ESRF, damage induced by superplastic deformation of a magnesium alloy is studied thanks to tomography analyses performed in 4D conditions, namely directly during high temperature deformation tests. Such conditions provide unique opportunities for investigating nucleation, growth and coalescence of cavities since it is thus possible to follow each cavity up to the fracture process.

“Cavity” formation in superplastically deformed aluminium alloys

1990 ◽  
Vol 48 (4) ◽  
pp. 958-959
Author(s):  
A. Cziráki ◽  
E. Ková-csetényi ◽  
T. Torma ◽  
T. Turmezey
Keyword(s):  
Grain Boundaries ◽  
Aluminium Alloys ◽  
Superplastic Deformation ◽  
Volume Fraction ◽  
Superplastic Forming ◽  
Polished Surface ◽  
Cavity Formation ◽  
Stress Concentrations ◽  
Electron Microscopic ◽  
Commercial Aluminium

It is known that the formation of cavities during superplastic deformation can be correlated with the development of stress concentrations at irregularities along grain boundaries such as particles, ledges and triple points. In commercial aluminium alloys Al-Fe-Si particles or other coarse constituents may play an important role in cavity formation.Cavity formation during superplastic deformation was studied by optical metallography and transmission scanning electron microscopic investigations on Al-Mg-Si and Al-Mg-Mn alloys. The structure of particles was characterized by selected area diffraction and X-ray micro analysis. The volume fraction of “voids” was determined on mechanically polished surface.It was found by electron microscopy that strongly deformed regions are formed during superplastic forming at grain boundaries and around coarse particles.According to electron diffraction measurements these areas consist of small micro crystallized regions. See Fig.l.Comparing the volume fraction and morphology of cavities found by optical microscopy a good correlation was established between that of micro crystalline regions.

Microstructural and Mechanical Behaviour Evaluation of Mg-Al-Zn Alloy Friction Stir Welded Joint

2020 ◽  
Vol 17 (3) ◽  
pp. 8150-8159
Author(s):  
Kulwant Singh ◽  
Gurbhinder Singh ◽  
Harmeet Singh
Keyword(s):  
Heat Treatment ◽  
Friction Stir Welding ◽  
Magnesium Alloys ◽  
Mechanical Performance ◽  
Fuel Efficiency ◽  
Research Work ◽  
Grain Structure ◽  
Tensile Fracture ◽  
Friction Stir ◽  
The Impact

The weight reduction concept is most effective to reduce the emissions of greenhouse gases from vehicles, which also improves fuel efficiency. Amongst lightweight materials, magnesium alloys are attractive to the automotive sector as a structural material. Welding feasibility of magnesium alloys acts as an influential role in its usage for lightweight prospects. Friction stir welding (FSW) is an appropriate technique as compared to other welding techniques to join magnesium alloys. Field of friction stir welding is emerging in the current scenario. The friction stir welding technique has been selected to weld AZ91 magnesium alloys in the current research work. The microstructure and mechanical characteristics of the produced FSW butt joints have been investigated. Further, the influence of post welding heat treatment (at 260 °C for 1 h) on these properties has also been examined. Post welding heat treatment (PWHT) resulted in the improvement of the grain structure of weld zones which affected the mechanical performance of the joints. After heat treatment, the tensile strength and elongation of the joint increased by 12.6 % and 31.9 % respectively. It is proven that after PWHT, the microhardness of the stir zone reduced and a comparatively smoothened microhardness profile of the FSW joint obtained. No considerable variation in the location of the tensile fracture was witnessed after PWHT. The results show that the impact toughness of the weld joints further decreases after post welding heat treatment.

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