Corrosion Modeling of Magnesium and Its Alloys for Biomedical Applications: Review

Abstract

Biodegradable metals have been under significant research as promising alternatives to the currently in-use nonbiodegradable materials in the field of supportive medical implants. In this scope, magnesium and its alloys were widely investigated due to their superior biocompatibility over other metals. Most of the research effort in the literature has been focused on assuring the biocompatibility, improving mechanical properties, and tailoring the corrosion rate of magnesium-based implants. Furthermore, considerable research was done to develop numerical models towards an inexpensive and fast designing tools capable of simulating the degradation/corrosion behavior of magnesium-based implants. Due to the complexity of the degradation process and the various factors that can be involved, several hypotheses were introduced to provide a realistic simulation of the corrosion behavior in vitro and in vivo. A review of the current literature hypothesis and different modeling constitutive equations for modeling the corrosion of magnesium alloys along with a summary of the supplementary experimental methods is provided in this paper.

Automated ex-situ detection of pitting corrosion and its effect on the mechanical integrity of rare earth magnesium alloy - WE43

“…A theoretical uniform corrosion is practically non-existent for light weight metal alloys, as microstructural inhomogeneities and impurities are introduced during the manufacturing process. Consequently, non-uniform corrosion phenomena such as pitting corrosion subsequently takes place on the material surface [11][12][13][14][15][16]. Pitting corrosion, which describes the locally varying corrosion rate, induces high variation of mechanical integrity of medical implants, which has limited their implementation in load-bearing applications Peer review under responsibility of KeAi Communications Co., Ltd. [17,18].…”

Computational modeling of degradation process of biodegradable magnesium biomaterials

“…The developed model falls in the categories of physical models of the corrosion process, which provide more insights of the process in comparison to the phenomenological models. The reason is that the phenomenological models focus on the elimination of elements to capture the loss of materials, which makes it impossible to model the formation of new chemical compounds or interaction of species [42]. The physical models, like the one developed in this study, are capable of capturing the underlying chemical interactions.…”

A Physical Approach to Simulate the Corrosion of Ceramic-Coated Magnesium Implants

“…The corrosion process in magnesium alloys can be summarized as two stages; the first short-term stage is the reaction-controlled period governed by the total chemical reaction in Equation (2). At this stage, corrosion products of magnesium hydroxide form on the surface and provide partial protection against the corrosive environment.…”

“…Bone fractures have a high incidence and are treated by osteosynthesis, which includes implanting fixation devices to hold the adjacent bone fragments still until the completion of the healing process [1]. The market size for these devices in the United States reached $6.9 billion in 2017 [2]. Bio-inert metals with high corrosion resistance such as stainless steel and titanium alloys have been the conventional materials used to make these fixation devices due to their strength and biocompatibility.…”