Modification of Biocorrosion and Cellular Response of Magnesium Alloy WE43 by Multiaxial Deformation

The study shows that multiaxial deformation (MAD) treatment leads to grain refinement in magnesium alloy WE43. Compared to the initial state, the MAD-processed alloy exhibited smoother biocorrosion dynamics in a fetal bovine serum and in a complete cell growth medium. Examination by microCT demonstrated retardation of the decline in the alloy volume and the Hounsfield unit values. An attendant reduction in the rate of accumulation of the biodegradation products in the immersion medium, a less pronounced alkalization, and inhibited sedimentation of biodegradation products on the surface of the alloy were observed after MAD. These effects were accompanied with an increase in the osteogenic mesenchymal stromal cell viability on the alloy surface and in a medium containing their extracts. It is expected that the more orderly dynamics of biodegradation of the WE43 alloy after MAD and the stimulation of cell colonization will effectively promote stable osteosynthesis, making repeat implant extraction surgeries unnecessary.

Download Full-text

Assessment of Galvanostatic Anodic Polarization to Accelerate the Corrosion of the Bioresorbable Magnesium Alloy WE43

Applied Sciences ◽

10.3390/app11052128 ◽

2021 ◽

Vol 11 (5) ◽

pp. 2128

Author(s):

Nils Wegner ◽

Frank Walther

Keyword(s):

Magnesium Alloy ◽

Corrosion Rate ◽

Dissolution Rate ◽

Anodic Polarization ◽

Technical Application ◽

Efficient Manner ◽

Corrosion Morphology ◽

Application Range ◽

Alloy We43

In the field of surgery, bioresorbable magnesium is considered a promising candidate. Its low corrosion resistance, which is disadvantageous for technical application, is advantageous for surgery since the implant fully degrades in the presence of the water-based body fluids, and after a defined time the regenerating bone takes over its function again. Therefore, knowledge of the corrosion behavior over several months is essential. For this reason, an in vitro short-time testing method is developed to accelerate the corrosion progress by galvanostatic anodic polarization without influencing the macroscopic corrosion morphology. The initial corrosion rate of the magnesium alloy WE43 is calculated by detection of the hydrogen volume produced in an immersion test. In a corresponding experimental setup, a galvanostatic anodic polarization is applied with a three-electrode system. The application range for the polarization is determined based on the corrosion current density from potentiodynamic polarization. To correlate the initial corrosion rate, and accelerated dissolution rate, the corrosion morphologies of both test strategies are characterized by microscopy images, as well as energy dispersive X-ray spectroscopy and Fourier-transform infrared spectroscopy. The results demonstrate that the dissolution rate can be increased in the order of decades with the limitation of a changed corrosion morphology with increasing polarization. With this approach, it is possible to characterize and exclude new unsuitable magnesium alloys in a time-efficient manner before they are used in subsequent preclinical studies.

Download Full-text

Experimental characterization and computational modelling of the effect of in vitro corrosion on the mechanical integrity of biodegradable magnesium alloy WE43 for orthopedic applications

10.26678/abcm.cobem2021.cob2021-0051 ◽

2021 ◽

Author(s):

Felipe Saconi ◽

Anish Roy ◽

Marcelo Leite Ribeiro

Keyword(s):

Magnesium Alloy ◽

Computational Modelling ◽

Experimental Characterization ◽

Mechanical Integrity ◽

Alloy We43 ◽

Biodegradable Magnesium ◽

Orthopedic Applications

Download Full-text

Features of in vitro and in vivo behaviour of magnesium alloy WE43

Materials Letters ◽

10.1016/j.matlet.2017.12.125 ◽

2018 ◽

Vol 215 ◽

pp. 308-311 ◽

Cited By ~ 12

Author(s):

Elena Lukyanova ◽

Natalia Anisimova ◽

Natalia Martynenko ◽

Mikhail Kiselevsky ◽

Sergey Dobatkin ◽

...

Keyword(s):

Magnesium Alloy ◽

Alloy We43

Download Full-text

STRUCTURE AND PROPERTIES OF AZ31 MAGNESIUM ALLOY AFTER COMBINATION OF HOT EXTRUSION AND ECAP

Acta Metallurgica Slovaca ◽

10.12776/ams.v23i3.971 ◽

2017 ◽

Vol 23 (3) ◽

pp. 222 ◽

Cited By ~ 7

Author(s):

Ondřej Hilšer ◽

Stanislav Rusz ◽

Wojciech Maziarz ◽

Jan Dutkiewicz ◽

Tomasz Tański ◽

...

Keyword(s):

Mechanical Properties ◽

Magnesium Alloy ◽

Hot Extrusion ◽

Az31 Magnesium Alloy ◽

Initial State ◽

Fine Grained ◽

Angular Pressing ◽

Ecap Process ◽

Average Grain Size ◽

Fine Grained Structure

<p>Equal channel angular pressing (ECAP) method was used for achieving very fine-grained structure and increased mechanical properties of AZ31 magnesium alloy. The experiments were focused on the, in the initial state, hot extruded alloy. ECAP process was realized at the temperature 250°C and following route Bc. It was found that combination of hot extrusion and ECAP leads to producing of material with significantly fine-grained structure and improves mechanical properties. Alloy structure after the fourth pass of ECAP tool with helix matrix 30° shows a fine-grained structure with average grain size of 2 µm to 3 µm and high disorientation between the grains. More experimental results are discussed in this article.</p>

Download Full-text

Corrosion and Corrosion Fatigue Properties of Additively Manufactured Magnesium Alloy WE43 in Comparison to Titanium Alloy Ti-6Al-4V in Physiological Environment

Materials ◽

10.3390/ma12182892 ◽

2019 ◽

Vol 12 (18) ◽

pp. 2892 ◽

Cited By ~ 4

Author(s):

Nils Wegner ◽

Daniel Kotzem ◽

Yvonne Wessarges ◽

Nicole Emminghaus ◽

Christian Hoff ◽

...

Keyword(s):

Titanium Alloy ◽

Fatigue Strength ◽

Magnesium Alloy ◽

Corrosion Fatigue ◽

Fatigue Properties ◽

Test Duration ◽

Medical Sector ◽

Manufacturing Techniques ◽

Alloy We43 ◽

Application Fields

Laser powder bed fusion (L-PBF) of metals enables the manufacturing of highly complex geometries which opens new application fields in the medical sector, especially with regard to personalized implants. In comparison to conventional manufacturing techniques, L-PBF causes different microstructures, and thus, new challenges arise. The main objective of this work is to investigate the influence of different manufacturing parameters of the L-PBF process on the microstructure, process-induced porosity, as well as corrosion fatigue properties of the magnesium alloy WE43 and as a reference on the titanium alloy Ti-6Al-4V. In particular, the investigated magnesium alloy WE43 showed a strong process parameter dependence in terms of porosity (size and distribution), microstructure, corrosion rates, and corrosion fatigue properties. Cyclic tests with increased test duration caused an especially high decrease in fatigue strength for magnesium alloy WE43. It can be demonstrated that, due to high process-induced surface roughness, which supports locally intensified corrosion, multiple crack initiation sites are present, which is one of the main reasons for the drastic decrease in fatigue strength.

Download Full-text