Experimental analysis and computational modelling of stress corrosion cracking and its influence on the structural integrity and mechanical properties of the magnesium alloy WE43
Main Article Content
Abstract
Magnesium alloys have been widely studied as biodegradable metals due to their low density and fast dissolution properties, making them a promising alternative for use as medical support implants. Their compatibility and degradation in the human body eliminate the need for a second surgery. However, magnesium alloys must maintain their mechanical integrity during the healing period. Despite their generally low corrosion resistance, they are highly susceptible to stress corrosion, which can lead to premature and sudden fractures of the implant. This susceptibility poses a significant challenge to their widespread use, underscoring the importance of analyzing their behavior in corrosive environments to understand their effects on mechanical properties and structural integrity. Computational modeling, particularly using "Digital Twin," plays a crucial role in orthopedic implant design, allowing for easier and faster optimization of the final shape based on criteria such as strength and stiffness, while ensuring compatibility with the bone healing process. This study aims to characterize and experimentally analyze the effects of stress corrosion on the WE43 alloy. Constant load tests were conducted using a portable and adaptable device equipped with compression springs to apply tensile force. Specimens were immersed in Simulated Body Fluid (SBF) to replicate the corrosive environment. A numerical corrosion model was developed to predict strength and mass loss, considering the effect of local stress on corrosion rate. The calibration of material model parameters was based on experimental results, with the numerical approach extendable to generic geometries. Consequently, the proposed numerical model proved to be an efficient tool for evaluating the structural integrity of biodegradable magnesium alloys and bone-implant assemblies, offering potential for use in designing optimized orthopedic implants. The study concluded that the simultaneous effect of stress and the corrosive environment (stress corrosion) was the primary cause of mechanical property loss.
Article Details
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References
2. Li L, Gao J, Wang Y. Evaluation of cyto-toxicity and corrosion behavior of alkali- heat-treated magnesium in simulated body fluid. Surface and Coatings Technology. 2004;185 (1):92-98.
3. Staiger MP, Pietak AM, Huadmai J, Dias G. Magnesium and its alloys as orthopedic biomaterials: A review. Biomaterials. 2006;27 (9):1728-1734.
4. Saris NEL, Mervaala E, Karppanen H, Khawaja JA, Lewenstam A. Magnesium: An update on physiological, clinical and analytical aspects. Clinica Chimica Acta. 2000;294(1):1-26.
5. Choudhary L, Raman RS. Magnesium alloys as body implants: Fracture mechanism under dynamic and static loadings in a physiological environment. Acta Biomaterialia. 2012;8(2):916-923.
6. Gastaldi D, Sassi V, Petrini L, Vedani M, Trasatti S, Migliavacca F. Continuum dam- age model for bioresorbable magnesium alloy devices—Application to coronary stents. Journal of the mechanical behavior of biomedical materials. 2011;4(3):352–365.
7. Esmaily M, Svensson J, Fajardo S, et al. Fundamentals and advances in magnesium alloy corrosion. Progress in Materials Science. 2017;89:92-193.
8. Song G, Atrens A. Understanding magnesium corrosion—a framework for improved alloy performance. Advanced engineering materials. 2003;5(12):837–858.
9. Pereira GS, Koga GY, Avila JA, et al. Corrosion resistance of WE43 Mg alloy in sodium chloride solution. Materials Chemistry and Physics. 2021;272:124930.
10. Seitz JM, Lucas A, Kirschner M. Magnesium-based compression screws: a novelty in the clinical use of implants. Jom. 2016;68:1177–1182.
11. Windhagen H, Radtke K, Weizbauer A, et al. Biodegradable magnesium-based screw clinically equivalent to titanium screw in hallux valgus surgery: Short term results of the first prospective, randomized, controlled clinical pilot study. Biomedical engineering online. 2013;12:62.
12. Winzer N, Atrens A, Song G, et al. A critical review of the stress corrosion cracking (SCC) of magnesium alloys. Advanced Engineering Materials. 2005;7(8):659–693.
13. Abdalla M, Joplin A, Elahinia M, Ibrahim H. Corrosion Modeling of Magnesium and Its Alloys for Biomedical Applications: Review. Corrosion and Materials Degradation. 2020;1 (2):219–248.
14. Gao Y, Wang L, Li L, et al. Effect of stress on corrosion of high-purity magnesium in vitro and in vivo. Acta Biomaterialia. 2019;83:477-486.
15. Fairman L, West JM. Stress corrosion cracking of a magnesium aluminium alloy. Corro- sion Science. 1965;5(10):711–716.
16. Grogan J, O’Brien B, Leen S, McHugh P. A corrosion model for bioabsorbable metallic stents. Acta Biomaterialia. 2011;7(9):3523-3533.
17. Ismail Bin Ismayatim I. Finite Element Analysis of Corroded Pipelines. 2009.
18. Maier P, Griebel A, Scheffler O, Schaffer J. Remaining strength of cold drawn and aged WE43 wires after corrosion. European cells materials. 2015;30:47.
19. Choudhary L, Singh Raman R, Hofstetter J, Uggowitzer PJ. In-vitro characterization of stress corrosion cracking of aluminium-free magnesium alloys for temporary bio-implant applications. Materials Science and Engineering: C. 2014;42:629-636.
20. Mardina Z, Venezuela J, Sjafrizal T, Shi Z, Dargusch MS, Atrens A. The influence of strain rate and annealing heat treatments on the corrosion and mechanical properties of WE43 and Zn7Ag biodegradable wires for application in soft tissue reconstructions. Materials Today Communications. 2023;35:105809.
21. Oyane A, Kim HM, Furuya T, Kokubo T, Miyazaki T, Nakamura T. Preparation and assessment of revised simulated body fluids. Journal of Biomedical Materials Research Part A. 2003;65A(2):188-195.
22. Saconi F. Caracteriza¸c˜ao experimental e modelagem num´erica do efeito da corros˜ao simulada nas propriedades mecˆanicas da liga de magn´esio biodegrad´avel WE43 para aplica¸c˜oes ortop´edicas. PhD thesisUniversidade de S˜ao Paulo 2021.
23. Boland EL, Shirazi RN, Grogan JA, McHugh PE. Mechanical and corrosion testing of magnesium WE43 specimens for pitting corrosion model calibration. Advanced Engi- neering Materials. 2018;20(10):1800656.
24. Dietzel W, Srinivasan PB, Atrens A. Testing and evaluation methods for stress corrosion cracking (SCC) in metals. in Stress Corrosion Cracking:133–166Elsevier 2011.
25. Yang Sj, Li Yd, Dong Py, Li Jm, Cao C, Ma Y. Effect of Annealing Process on the Microstructures and Mechanical Properties of AZ31B/A356 Composite Plate Fabricated by Cast Rolling. Materials Research. 2019;22 (4):e20190001.
26. Gu X, Zhou W, Zheng Y, et al. Corrosion fatigue behaviors of two biomedical Mg alloys – AZ91D and WE43 – In simulated body fluid. Acta Biomaterialia. 2010;6(12):4605-4613.
27. Fairman L, Bray H. Transgranular see in Mg-Al alloys. Corrosion Science.1971;11(7): 533–541
28. Stampella R, Procter R, Ashworth V. Environmentally-induced cracking of magnesium. Corrosion Science. 1984;24(4):325–341.
29. Wu W, Gastaldi D, Yang K, Tan L, Petrini L, Migliavacca F. Finite element analyses for design evaluation of biodegradable magnesium alloy stents in arterial vessels. Materials Science and Engineering: B. 2011;176(20):1733–1740.