Micro-arc oxidation of AZ91 Mg alloy: An in-situ electrochemical study

Micro-arc oxidation (MAO) method was used for the surface modification of MB3 magnesium alloy. The morphology feature, phase composition, and chemical composition of the formed ceramic coatings were studied by metallographic microscope, scanning electron microscopy (SEM), XRD, respectively. Drop test has been applied to study the corrosion resistance of MB3 Mg alloy with and without micro-arc oxidation treatment. The present result indicates that, through MAO, ceramic coatings were in-situ fabricated on the surface of MB3 Mg alloy, the micro-arc oxidation coating is relatively dense and uniform, maximum thickness is more than 97μm. The dominant phase of the coating is spinal Mg2SiO4 (Forsterite) and dissociative MgO (Periclase). Drop test shows that after oxidation the corrosion resistance of MB3 Mg alloy is greatly improved.

Download Full-text

In situ synchrotron tomography of the solidification of an Elektron 21 Mg alloy

Advanced Engineering Materials ◽

10.1002/adem.202100383 ◽

2021 ◽

Author(s):

Domonkos Tolnai ◽

Sarkis Gavras ◽

Fabian Wilde ◽

Jörg U. Hammel ◽

Stefan Bruns

Keyword(s):

Mg Alloy ◽

Synchrotron Tomography

Download Full-text

Thermodynamics of In Situ Formation of Mg2Si and MgO in AZ91D /Flyash Composites

Materials Science Forum ◽

10.4028/www.scientific.net/msf.686.378 ◽

2011 ◽

Vol 686 ◽

pp. 378-381

Author(s):

Si Rong Yu ◽

Zhi Qiu Huang ◽

Jia An Liu

Keyword(s):

Fly Ash ◽

Thermodynamic Calculation ◽

Interfacial Reactions ◽

Mg Alloy ◽

Free Enthalpy ◽

Alloy Matrix ◽

Microstructure Observation ◽

Enthalpy Changes ◽

Fly Ash Cenospheres

Novel AZ91D Mg alloy/fly-ash cenospheres (AZ91D/FAC) composites were fabricated by melt stir technique. The thermodynamic analyses of the interfacial reactions, the microstructure observation, and the phase analyses of the AZ91D/FAC composites were investigated. The results showed that the cenospheres were almost filled with Mg alloy matrix. In-situ MgO and Mg2Si phases were formed in Mg alloy matrix and near the interfaces between the cenospheres and Mg alloy matrix. Through the thermodynamic calculation, it can be found that the standard free enthalpy changes of these interfacial reactions are all negative at the temperature of Mg alloy melt preparation in this work, and these reactions can occur.

Download Full-text

Role of Second-Phase Particles on In Situ Deformation of an AZ80 Mg Alloy

Applications of Microscopy in Materials and Life Sciences - Springer Proceedings in Materials ◽

10.1007/978-981-16-2982-2_6 ◽

2021 ◽

pp. 55-64

Author(s):

R. Sarvesha ◽

W. Alam ◽

J. Jain ◽

S. S. Singh

Keyword(s):

Mg Alloy ◽

Second Phase ◽

Second Phase Particles ◽

In Situ Deformation

Download Full-text

In-situ characterization of continuous dynamic recrystallization during hot torsion of an Al–Si–Mg alloy

Journal of Alloys and Compounds ◽

10.1016/j.jallcom.2019.153282 ◽

2020 ◽

Vol 822 ◽

pp. 153282 ◽

Cited By ~ 2

Author(s):

David Canelo-Yubero ◽

Zsolt Kovács ◽

J.F. Thierry Simonet Fotso ◽

Domonkos Tolnai ◽

Norbert Schell ◽

...

Keyword(s):

Dynamic Recrystallization ◽

Mg Alloy ◽

In Situ Characterization ◽

Continuous Dynamic Recrystallization ◽

Hot Torsion ◽

Continuous Dynamic

Download Full-text

In-situ SEM investigation on fatigue behaviors of additive manufactured Al-Si10-Mg alloy at elevated temperature

Engineering Fracture Mechanics ◽

10.1016/j.engfracmech.2019.03.040 ◽

2019 ◽

Vol 214 ◽

pp. 149-163 ◽

Cited By ~ 17

Author(s):

Zhen Wang ◽

Wenwang Wu ◽

Guian Qian ◽

Lijuan Sun ◽

Xide Li ◽

...

Keyword(s):

Elevated Temperature ◽

Mg Alloy ◽

Sem Investigation

Download Full-text

Morphology and Wear Resistance of Composite Coatings Formed on a TA2 Substrate Using Hot-Dip Aluminising and Micro-Arc Oxidation Technologies

Materials ◽

10.3390/ma12050799 ◽

2019 ◽

Vol 12 (5) ◽

pp. 799 ◽

Cited By ~ 5

Author(s):

Shaopeng Wang ◽

Lian Zhou ◽

Changjiu Li ◽

Zhengxian Li ◽

Hongzhan Li

Keyword(s):

Wear Resistance ◽

Surface Composition ◽

Pure Titanium ◽

Titanium Substrate ◽

Ceramic Coatings ◽

Oxide Ceramic ◽

Pure Aluminium ◽

X Ray ◽

Micro Arc Oxidation

Aluminium layers were coated onto the surface of pure titanium using hot-dip aluminising technology, and then the aluminium layers were in situ oxidised to form oxide ceramic coatings, using the micro-arc oxidation (MAO) technique. The microstructure and composition distribution of the hot-dip aluminium coatings and ceramic layers were studied by using scanning electron microscopy and energy-dispersive X-ray spectroscopy. The phase structure of the MAO layers was studied using X-ray diffraction. The surface composition of the MAO layer was studied by X-ray photoelectron spectroscopy. The wear resistance of the pure titanium substrate and the ceramic layers coated on its surface were evaluated by using the ball-on-disc wear method. Therefore, aluminising coatings, which consist of a diffusion layer and a pure aluminium layer, could be formed on pure titanium substrates using the hot-dip aluminising method. The MAO method enabled the in-situ oxidation of hot-dip pure aluminium layers, which subsequently led to the formation of ceramic layers. Moreover, the wear resistance values of the ceramic layers were significantly higher than that of the pure titanium substrate.

Download Full-text