scholarly journals On the Corrosion Fatigue of Magnesium Alloys Aimed at Biomedical Applications: New Insights from the Influence of Testing Frequency and Surface Modification of the Alloy ZK60

Materials ◽  
2022 ◽  
Vol 15 (2) ◽  
pp. 567
Author(s):  
Mikhail Linderov ◽  
Alexander Brilevsky ◽  
Dmitry Merson ◽  
Alexei Danyuk ◽  
Alexei Vinogradov
Keyword(s):  
Magnesium Alloys ◽  
Corrosion Fatigue ◽  
Structural Integrity ◽  
Corrosion Damage ◽  
Critical Issue ◽  
Fatigue Behaviour ◽  
Variable Loading ◽  
Premature Failure ◽  
Testing Frequency ◽  
Structural Applications

Magnesium alloys are contemporary candidates for many structural applications of which medical applications, such as bioresorbable implants, are of significant interest to the community and a challenge to materials scientists. The generally poor resistance of magnesium alloys to environmentally assisted fracture, resulting, in particular, in faster-than-desired bio-corrosion degradation in body fluids, strongly impedes their broad uptake in clinical practice. Since temporary structures implanted to support osteosynthesis or healing tissues may experience variable loading, the resistance to bio-corrosion fatigue is a critical issue that has yet to be understood in order to maintain the structural integrity and to prevent the premature failure of implants. In the present communication, we address several aspects of the corrosion fatigue behaviour of magnesium alloys, using the popular commercial ZK60 Mg-Zn-Zr alloy as a representative example. Specifically, the effects of the testing frequency, surface roughness and metallic coatings are discussed in conjunction with the fatigue fractography after the testing of miniature specimens in air and simulated body fluid. It is demonstrated that accelerated environmentally assisted degradation under cyclic loading occurs due to a complicated interplay between corrosion damage, stress corrosion cracking and cyclic loads. The occurrence of corrosion fatigue in Mg alloys is exaggerated by the significant sensitivity to the testing frequency. The fatigue life or strength reduced remarkably with a decrease in the test frequency.

Corrosion Fatigue Behaviour of a Common AZ91D Magnesium Alloy in Modified Simulated Body Fluid

2014 ◽  
Vol 891-892 ◽  
pp. 267-272 ◽  
Author(s):  
Sajjad Jafari ◽  
R.K. Singh Raman
Keyword(s):  
Magnesium Alloy ◽  
Simulated Body Fluid ◽  
Magnesium Alloys ◽  
Corrosion Fatigue ◽  
Body Fluid ◽  
Fatigue Behaviour ◽  
New Paradigm ◽  
Metallic Implants ◽  
Alloy Az91d ◽  
Cast Magnesium

Use of Magnesium alloys as body implants are breaking into a new paradigm of biomedical engineering as they are biocompatible, biodegradable and have mechanical properties close to that of bone. Even though corrosion fatigue (CF) and stress corrosion cracking (SCC) failures are among the most common concerns for metallic implants, CF behaviour of magnesium alloys in physiological environments has received little attention. This article reports the CF results of a common cast magnesium alloy (AZ91D) in modified simulated body fluid (m-SBF). Results showed that there was a remarkable difference in fatigue strength of Mg alloys when tests were performed in m-SBF.

scholarly journals Management of Airframe In-Service Pitting Corrosion by Decoupling Fatigue and Environment

2021 ◽  
Vol 2 (3) ◽  
pp. 493-511
Author(s):  
Loris Molent ◽  
Russell Wanhill
Keyword(s):  
Corrosion Fatigue ◽  
Pitting Corrosion ◽  
Structural Integrity ◽  
Corrosion Damage ◽  
Fatigue Loading ◽  
Cost Driver ◽  
Service Environments ◽  
Corrosion Pits ◽  
The Impact ◽  
Fatigue Corrosion

Corrosion-induced maintenance is a significant cost driver and availability degrader for aircraft structures. Although well-established analyses enable assessing the corrosion impact on structural integrity, this is not the case for fatigue nucleation and crack growth. This forces fleet managers to directly address detected corrosion to maintain flight safety. Corrosion damage occurs despite protection systems, which inevitably degrade. In particular, pitting corrosion is a common potential source of fatigue. Corrosion pits are discontinuities whose metrics can be used to predict the impact on the fatigue lives of structural components. However, a damage tolerance (DT) approach would be more useful and flexible. A potential hindrance to DT has been the assumption that corrosion-induced fatigue nucleation transitions to corrosion fatigue, about which little is known for service environments. Fortunately, several sources indicate that corrosion fatigue is rare for aircraft, and corrosion is largely confined to ground situations because aircraft generally fly at altitudes with low temperature and humidity Thus, it is reasonable to propose the decoupling of corrosion from the in-flight dynamic (fatigue) loading. This paper presents information to support this proposition, and provides an example of how a DT approach can allow deferring corrosion maintenance to a more opportune time.

358 Corrosion Fatigue Behaviour of Magnesium Alloys with Anodic Oxide Films in Distilled Water

2007 ◽  
Vol 2007.56 (0) ◽  
pp. 165-166
Author(s):  
Takashi OHASHI ◽  
Yoshihiko UEMATSU ◽  
Keiro TOKAJI ◽  
Kazuhito Nishinaka ◽  
Masahiro Akimoto
Keyword(s):  
Magnesium Alloys ◽  
Corrosion Fatigue ◽  
Oxide Films ◽  
Anodic Oxide ◽  
Fatigue Behaviour ◽  
Distilled Water ◽  
Anodic Oxide Films

scholarly journals Soil microbiomes mediate degradation of vinyl ester-based polymer composites

2020 ◽  
Vol 1 (1) ◽  
Author(s):  
Adam M. Breister ◽  
Muhammad A. Imam ◽  
Zhichao Zhou ◽  
Md Ariful Ahsan ◽  
Juan C. Noveron ◽  
...  
Keyword(s):  
Polymer Composites ◽  
Polymer Composite ◽  
Structural Integrity ◽  
Abiotic Factors ◽  
High Strength ◽  
Strength Properties ◽  
Naturally Occurring ◽  
Structural Applications ◽  
Acrylate Esters ◽  
Bacterial Groups

AbstractPolymer composites are attractive for structural applications in the built environment due to their lightweight and high strength properties but suffer from degradation due to environmental factors. While abiotic factors like temperature, moisture, and ultraviolet light are well studied, little is known about the impacts of naturally occurring microbial communities on their structural integrity. Here we apply complementary time-series multi-omics of biofilms growing on polymer composites and materials characterization to elucidate the processes driving their degradation. We measured a reduction in mechanical properties due to biologically driven molecular chain breakage of esters and reconstructed 121 microbial genomes to describe microbial diversity and pathways associated with polymer composite degradation. The polymer composite microbiome is dominated by four bacterial groups including the Candidate Phyla Radiation that possess pathways for breakdown of acrylate, esters, and bisphenol, abundant in composites. We provide a foundation for understanding interactions of next-generation structural materials with their natural environment that can predict their durability and drive future designs.

Modification in Texture of Magnesium by the Addition of Rare Earth Elements and its Influence on Mechanical Properties

2012 ◽  
Vol 736 ◽  
pp. 307-315 ◽  
Author(s):  
Murugavel Suresh ◽  
Satyam Suwas
Keyword(s):  
Mechanical Properties ◽  
Rare Earth ◽  
Magnesium Alloys ◽  
Aluminium Alloys ◽  
Room Temperature ◽  
Main Obstacle ◽  
Rare Earth Addition ◽  
Structural Applications ◽  
Re Elements ◽  
The Relationship

Mg alloys show limited room temperature formability compared to its lightweight counterpart aluminium alloys, which is a main obstacle in using this metal for most of the structural applications. However, it is known that grain refinement and texture control are the two possibilities for the improvement of formability of magnesium alloys. Amongst the approaches attempted for the texture weakening, additions through of rare-earth (RE) elements have been found most effective. The relationship between the texture and ductility is well established. In this paper, the effect of rare earth addition on texture weakening has been summarized for various magnesium alloys under the two most common modes of deformation methods.

Sign in / Sign up

Export Citation Format

Share Document