Mg-based Material Research Articles

Nanoporous Mg–Zn materials for efficient and controllable in-situ hydrogen generation

Mg is a research focus in the field of in-situ hydrogen generation due to its high activity, abundant reserves and mature circulation mode. However, the passivation issue of Mg bulks and the explosion risk of Mg powders hinder its practical application. In this work, we propose a novel nanoporous Mg-based material, whose nanoscale pores significantly reduce the passivation, and the self-supporting characteristic ensures its safe application. By co-depositing Mg–Zn and adjusting their ratios, three kinds of nanoporous Mg–Zn materials with different morphology and composition are obtained, that is, granular nanoporous (GNP) Mg–Zn, coral-like nanoporous (CNP) Mg–Zn and lotus root-like nanoporous (LNP) Mg–Zn materials. The GNP Mg–Zn material shows the best hydrogen generation performance among the three nanoporous Mg–Zn materials, and realizes an efficient and controllable hydrogen generation. The formation mechanism, the morphology evolution and the hydrogen generation mechanism of the nanoporous Mg–Zn materials are discussed in detail.

INFLUENCE OF MG-CYLINDERS ON BONE AND CARTILAGE IN OSTEOARTHRITIS

There are no efficient treatment options for osteoarthritis (OA) that delay further progression. Besides osteoinduction, there is growing evidence of also anti-inflammatory, angiogenetic and neuroprotective effects of biodegradable magnesium-based biomaterials. Their use for the treatment of cartilage lesions in contrast is not well-evaluated yet.Mg-cylinders were analysed in an in vitro and in vivo OA model. In vitro, SCP-1 stem cell line was analysed under inflammatory conditions and Mg-impact. In vivo, small Mg- and WE43 alloy-cylinders (1mm × 0,5mm) were implanted into the subchondral bone of the knee joint of 24 NZW rabbits after establishment of OA. As control, another 12 rabbits received only drill-holes. µCT-scan were performed and assessed for changes in bone volume and density. After euthanasia, cartilage was evaluated macroscopically and histologically after Safranin-O-staining. Furthermore, staining with CD271 directed antibody was performed to assess neuro-reactivity.In vitro, an increased gene expression of extracellular matrix proteins as collagen II or aggrecan even under inflammatory conditions was observed under Mg-impact. In vivo, µCT evaluation revealed twice-elevated values for bone volume in femoral condyles with Mg-cylinders compared to controls while density remained unchanged. Cartilage showed no significant differences between the groups. Mg- and WE-samples showed significantly lower levels of CD271+ cells in the cartilage and bone of the operated joints than in non-operated joints, which was not the case in the Drilling-group. Furthermore, bone in operated knees of Drilling-group showed a strong trend to an increase in CD271+ cells compared to both Cylinder-groups. Counting of CD271+ vessels revealed that this difference was attributable to a higher amount of these vessels.The in vitro results indicate a potential cartilage regenerative activity of the degradable Mg-based material. While so far there was no positive effect on the cartilage itself in vivo, implantation of Mg-cylinders seemed to reduce pain-mediating vessels.Acknowledgements: This work is funded by the German Research Foundation (DFG, project number 404534760). We thank Björn Wiese for production of the cylinders.

A significant comparison between magnesium-based binder and other inorganic cementitious materials for the restoration of brick-carved cultural relics

The uniqueness of brick-carved cultural relics causes a higher requirement for restoration techniques and repair materials. Considering the weather resistance and compatibility with the original substrate bricks, three types of inorganic binders were selected as alternative options for brick carving restoration: Ca-based hydraulic lime, Si-based silica sol, and Mg-based magnesium oxychloride. Multiple experiments were conducted to investigate the compatibility of the replica bricks produced using these binders. The adhesive properties and infiltration reinforcement of the binders were also taken into consideration to evaluate the feasibility of these materials’ application for the restoration of brick-carving cultural relics. The results showed that the Mg-based cementitious material led to the best performance, maintaining their original physical properties while restoring the original cohesion. A successful in situ test was conducted on the Southern Song brick carvings (1152 CE) inside the Liuhe Pagoda (Fig. 1 a) in Hangzhou.

Enhancing Multiple Properties of a Multicomponent Mg-Based Alloy Using a Sinterless Turning-Induced Deformation Technique

A magnesium-based multi-component alloy (MCA), Mg70Al18Zn6Ca4Y2, was successfully synthesized using the Turning-Induced Deformation (TID) method, with promising improvements in multiple properties such as damping capabilities, hardness (11% to 34% increase), and strength (5% to 15% increase) over its conventional cast and extruded equivalent which has already been established as a high-performance MCA exhibiting superior mechanical properties over other Mg-based materials while retaining acceptable ductility. This new TID-based MCA comes only at a slight compromise in the aspects of ductility, ignition resistance, and corrosion resistance, which was previously observed in other TID-based materials. In addition, the general microstructure and secondary phases of this MCA were retained even when using the TID method, with only minimal porosity (<1%) incurred during the process. Furthermore, the ignition temperature of the TID Mg70Al18Zn6Ca4Y2 remained very high at 915 °C, positioning it as a potential Mg-based material suitable for aerospace applications with a high ignition resistance. This is tantamount to a successful application of TID to yet another class of Mg-based materials and opening the door to future explorations of such materials.

Brushite-coated Mg–Nd–Zn–Zr alloy promotes the osteogenesis of vertebral laminae through IGF2/PI3K/AKT signaling pathway

Biodegradable magnesium (Mg) alloys have been extensively investigated in orthopedic implants due to their suitable mechanical strength and high biocompatibility. However, no studies have reported whether Mg alloys can be used to repair lamina defects, and the biological mechanisms regulating osteogenesis are not fully understood. The present study developed a lamina reconstruction device using our patented biodegradable Mg-Nd-Zn-Zr alloy (JDBM), and brushite (CaHPO4·2H2O, Dicalcium phosphate dihydrate, DCPD) coating was developed on the implant. Through in vitro and in vivo experiments, we evaluated the degradation behavior and biocompatibility of DCPD-JDBM. In addition, we explored the potential molecular mechanisms by which it regulates osteogenesis. In vitro, ion release and cytotoxicity tests revealed that DCPD-JDBM had better corrosion resistance and biocompatibility. We found that DCPD-JDBM extracts could promote MC3T3-E1 osteogenic differentiation via the IGF2/PI3K/AKT pathway. The lamina reconstruction device was implanted on a rat lumbar lamina defect model. Radiographic and histological analysis showed that DCPD-JDBM accelerated the repair of rat lamina defects and exhibited lower degradation rate compared to uncoated JDBM. Immunohistochemical and qRT-PCR results showed that DCPD-JDBM promoted osteogenesis in rat laminae via IGF2/PI3K/AKT pathway. This study shows that DCPD-JDBM is a promising biodegradable Mg-based material with great potential for clinical applications.

Phase Transformation and Performance of Mg-Based Hydrogen Storage Material by Adding ZnO Nanoparticles.

ZnO nanoparticles in a spherical-like structure were synthesized via filtration and calcination methods, and different amounts of ZnO nanoparticles were added to MgH2 via ball milling. The SEM images revealed that the size of the composites was about 2 μm. The composites of different states were composed of large particles with small particles covering them. After the absorption and desorption cycle, the phase of composites changed. The MgH2-2.5 wt% ZnO composite reveals excellent performance among the three samples. The results show that the MgH2-2.5 wt% ZnO sample can swiftly absorb 3.77 wt% H2 in 20 min at 523 K and even at 473 K for 1 h can absorb 1.91 wt% H2. Meanwhile, the sample of MgH2-2.5 wt% ZnO can release 5.05 wt% H2 at 573 K within 30 min. Furthermore, the activation energies (Ea) of hydrogen absorption and desorption of the MgH2-2.5 wt% ZnO composite are 72.00 and 107.58 KJ/mol H2, respectively. This work reveals that the phase changes and the catalytic action of MgH2 in the cycle after the addition of ZnO, and the facile synthesis of the ZnO can provide direction for the better synthesis of catalyst materials.

Role of CNT in influencing the mechanical properties of the Mg-based composites: An overview

Because of their lower density, good surface-to-volume ratio, tensile strength, and thermal conductivity, CNTs have been used to create high-strength MMC (metal matrix composite). While dealing with CNT, uniform dispersion is the most critical aspect. Therefore, proper usage of processing technique and amount of reinforcement plays a key role in providing the uniform composition of powder in the matrix throughout. Adhering/Controlling the amount of CNT in the Magnesium-based matrix material attributed to the more refine microstructures and high strength of the MMC.Among the various fabrication approaches, Powder metallurgy entails the homogenous dispersion of the CNT in the matrix materials indicating the improvement in the mechanical behavior and the micro-structure characteristics of the composite. The review papers highlight the various aspects of CNT (Carbon Nanotube) in Mg-based matrix material while dealing with microstructure and mechanical behaviour analysis of Mg-MMC.

Advancements in the Additive Manufacturing of Magnesium and Aluminum Alloys through Laser-Based Approach.

Complex structures can now be manufactured easily utilizing AM technologies to meet the pre-requisite objectives such as reduced part numbers, greater functionality, and lightweight, among others. Polymers, metals, and ceramics are the few materials that can be used in AM technology, but metallic materials (Magnesium and Aluminum) are attracting more attention from the research and industrial point of view. Understanding the role processing parameters of laser-based additive manufacturing is critical to maximize the usage of material in forming the product geometry. LPBF (Laser powder-based fusion) method is regarded as a potent and effective additive manufacturing technique for creating intricate 3D forms/parts with high levels of precision and reproducibility together with acceptable metallurgical characteristics. While dealing with LBPF, some degree of porosity is acceptable because it is unavoidable; hot ripping and cracking must be avoided, though. The necessary manufacturing of pre-alloyed powder and ductility remains to be the primary concern while dealing with a laser-based additive manufacturing approach. The presence of the Al-Si eutectic phase in AlSi10Mg and AlSi12 alloy attributing to excellent castability and low shrinkage, attaining the most attention in the laser-based approach. Related studies with these alloys along with precipitation hardening and heat treatment processing were discussed. The Pure Mg, Mg-Al alloy, Mg-RE alloy, and Mg-Zn alloy along with the mechanical characteristics, electrochemical durability, and biocompatibility of Mg-based material have been elaborated in the work-study. The review article also summarizes the processing parameters of the additive manufacturing powder-based approach relating to different Mg-based alloys. For future aspects, the optimization of processing parameters, composition of the alloy, and quality of powder material used will significantly improve the ductility of additively manufactured Mg alloy by the LPBF approach. Other than that, the recycling of Mg-alloy powder hasn't been investigated yet. Meanwhile, the post-processing approach, including a homogeneous coating on the porous scaffolds, will mark the suitability in terms of future advancements in Mg and Al-based alloys.

Mg-Ni-Nb2O5 Composite Produced by High-Pressure Torsion

A Mg-based composite material has been produced by the consolidation at room temperature of a Mg-5wt.% Ni-2wt.% Nb2O5 powder mixture subjected to high-pressure torsion (HPT), one of the processing methods to induce severe plastic deformations. The microstructure, density, and microhardness of the consolidated disks were characterized after the application of up to 30 revolutions in torsion under compression stresses of 3 and 5 GPa. According to the density measurements, the composite was consolidated in full after the application of five revolutions, although disks subjected to only one revolution exhibited densities close to the maximum measured value. On the other hand, grain size and microhardness measurements showed that differences existed at locations near the center and the periphery of the HPT-processed disks. Under the stress of 5 GPa, the grain size in the central regions stabilized at about 0.35 μm after five revolutions, while at the peripherical regions it gradually decreased with an increasing number of revolutions down to about 0.15 μm after 30 revolutions. In turn, the microhardness measured along a diametral cross section steadily increased with the number of revolutions between 1 and 10 revolutions, maintaining a gradient from the center to the periphery in all cases. With the application of 20 and 30 revolutions, only the peripheral regions increased considerably in hardness. It was discovered that the magnesium particles in the initial powder mixture had formed an oxide—hydroxide surface layer, which changed the expected final density of the consolidated material by about 2 to 4.5%. This superficial contamination of the Mg powders did not prevent the material from achieving full consolidation.

Effect of novel La-based alloy modification on hydrogen storage performance of magnesium hydride: First-principles calculation and experimental investigation

LaNi4.5X0.5(X = Fe, Co, Al, Ni) alloys are prepared and doped into MgH2 by ball milling to enhance the hydrogen storage performance, respectively. Both hydrogenation & dehydrogenation kinetics are experimentally measured, and the results indicate that LaNi4.5Fe0.5 doped MgH2 exhibits the top H2 absorption/desorption performance compared with other samples. It is worth noting that the optimal doping amount of LaNi4.5Fe0.5 is selected as 15 wt.% combined with the consideration of working temperature and H2 storage capacity. More importantly, the as-prepared MgH2-15 wt.%LaNi4.5Fe0.5 sample may rapidly introduce the equivalent H2 within 1000 s at mild temperature and pressure of 200 °C and 1 MPa, and it is completely impossible for MgH2 to occur any hydrogenation under this operation conditions. Moreover, the activation energy barriers for hydrogenation & dehydrogenation decline by 62.90% & 20.75% respectively, suggesting the successful doping and property of La-based alloy inside MgH2 as expected. In addition, a variety of as-prepared alloys are experimentally compared and discussed, and the related the heterostructure interface, electronic structure and the formation energy of H vacancy are carried out based on the first-principles calculation, which confirm that LaNi4.5Fe0.5 owns the most favorable catalytic modification effect on Mg-based material.

The effects of crystalline defects on hydrogen absorption kinetics of catalyzed MgH2 at ambient conditions

The high operation temperature has limited the practical applications of magnesium hydride. Although several techniques can significantly improve Mg hydride's high-temperature de/hydrogenation properties, the hydrogenation performance at relatively low temperatures degrades rapidly during cycling. Herein, we study the hydrogenation kinetics under ambient temperature after specific cycle numbers, and the microstructural evolution of the catalyzed Mg hydride during hydrogen sorption cycling. The results show that the average crystallite size increases with the increase of cycle numbers, and the dislocation density and microstrain decrease. However, the hydrogenation kinetic rate can be restored by subjecting the performance-degraded sample to an ultra-high-energy high-pressure planetary ball mill again. This suggests that the nanocrystalline structure with a high concentration of defects in the ball-milled Mg-based material is critical for achieving a good kinetic rate of hydrogen adsorption at room temperature. Furthermore, defect concentration effects on hydrogen absorption are more significant than crystallite size. This result provides a direction for improving Mg-based hydrogen storage materials for practical application.

Significance of Alloying Elements on the Mechanical Characteristics of Mg-Based Materials for Biomedical Applications

Magnesium alloys are widely employed in various applications due to their high strength-to-weight ratio and superior mechanical properties as compared to unalloyed Magnesium. Alloying is considered an important way to enhance the strength of the metal matrix composite but it significantly influences the damping property of pure magnesium, while controlling the rate of corrosion for Mg-based material remains critical in the biological environment. Therefore, it is essential to reinforce the magnesium alloy with a suitable alloying element that improves the mechanical characteristics and resistance to corrosion of Mg-based material. Biocompatibility, biodegradability, lower stress shielding effect, bio-activeness, and non-toxicity are the important parameters for biomedical applications other than mechanical and corrosion properties. The development of various surface modifications is also considered a suitable approach to control the degradation rate of Mg-based materials, making lightweight Mg-based materials highly suitable for biomedical implants. This review article discusses the various binary and ternary Mg alloys, which are mostly composed of Al, Ca, Zn, Mn, and rare earth (RE) elements as well as various non-toxic elements which are Si, Bi, Ag, Ca, Zr, Zn, Mn, Sr, Li, Sn, etc. The effects of these alloying elements on the microstructure, the mechanical characteristics, and the corrosion properties of Mg-based materials were analyzed. The mechanical and corrosion behavior of Mg-based materials depends upon the percentage of elements and the number of alloying elements used in Mg. The outcomes suggested that ZEK100, WE43, and EW62 (Mg-6% Nd-2% Y-0.5% Zr) alloys are effectively used for biomedical applications, having preferable biodegradable, biocompatible, bioactive implant materials with a lower corrosion rate.

Simulating In Vitro the Bone Healing Potential of a Degradable and Tailored Multifunctional Mg-Based Alloy Platform

This work intended to elucidate, in an in vitro approach, the cellular and molecular mechanisms occurring during the bone healing process, upon implantation of a tailored degradable multifunctional Mg-based alloy. This was prepared by a conjoining anodization of the bare alloy (AZ31) followed by the deposition of a polymeric coating functionalized with hydroxyapatite. Human endothelial cells and osteoblastic and osteoclastic differentiating cells were exposed to the extracts from the multifunctional platform (having a low degradation rate), as well as the underlying anodized and original AZ31 alloy (with higher degradation rates). Extracts from the multifunctional coated alloy did not affect cellular behavior, although a small inductive effect was observed in the proliferation and gene expression of endothelial and osteoblastic cells. Extracts from the higher degradable anodized and original alloys induced the expression of some endothelial genes and, also, ALP and TRAP activities, further increasing the expression of some early differentiation osteoblastic and osteoclastic genes. The integration of these results in a translational approach suggests that, following the implantation of a tailored degradable Mg-based material, the absence of initial deleterious effects would favor the early stages of bone repair and, subsequently, the on-going degradation of the coating and the subjacent alloy would increase bone metabolism dynamics favoring a faster bone formation and remodeling process and enhancing bone healing.

Development of a Model System for Gas Cavity Formation Behavior of Magnesium Alloy Implantation.

Clinical applications of magnesium (Mg)-based screws have reported gas cavity formation in the surrounding tissue, which sometimes delays the fixation of the bone fracture. The gas cavity formation is considered to depend on the balance between hydrogen generation by Mg corrosion reacting with water in the body fluid and its diffusion into the surrounding tissue by capillary flow. In order to understand the gas cavity formation behavior by Mg-based material implantation, we developed a new in vitro model system to recreate this cavity formation phenomenon: the hydrogen generation by corrosion and its diffusion into the medium. A model tissue is prepared by gelation of the cell culture medium in a sterile condition. The immersion of Mg alloy samples was performed under 5% CO2 atmosphere with periodic observation by X-ray computed tomography, which enabled us to observe gas cavity growth up to 28 d. For demonstrating the usefulness of our model system, Mg alloy samples with different corrosion rates were prepared by a biodegradable polymer coating. AZ31 screws were spin-coated by poly-l-lactide (PLLA) and classified into three groups by their coating thickness as 1.0 ± 0.0, 1.6 ± 0.2, and 2.0 ± 0.1 μm (ave. ± s.d.). Upon their immersion into the model tissue, the gas cavity volumes formed were 1.57 ± 0.23, 1.06 ± 0.22, and 0.38 ± 0.09 mm3/mm2 for 1.0, 1.6, and 2.0 μm coating samples, having the weight loss of 20.2 ± 2.93, 18.5 ± 2.84, and 11.3 ± 3.54 μg/mm2, respectively (ave. ± s.d.). This result clearly indicates the dependence of gas cavity formation on the corrosion rate of the sample. The gas cavity volume was only 3.3∼7.5% of the total hydrogen gas volume estimated based on the weight loss of the samples at 28 d, which is in the range of those calculated from the clinical report (3.2∼9.4% at 4w). This system can be an effective tool to investigate the gas cavity formation behavior and contribute to understand the mechanisms and controlling factors of this phenomenon.

Kinetic/thermodynamic study on improved hydrolysis hydrogen generation of Mg-doped bismuth series oxysalt

<p indent="0mm">Study of high efficiency hydrogen production materials has attracted many researchers’ attention. Mg-based hydrogen production material has the advantages of wide sources, mild reaction, simple process, safety control, and high hydrogen production capacity. In this article, Mg was doped with bismuth series oxysalt Bi_{<italic>x</italic>}M_{<italic>y</italic>}O_{<italic>z</italic>} (M = Ti, V, Cr, Mo, W) by high energy ball milling method to improve the performance of hydrolytic hydrogen generation for the first time. It was found that Bi₂MoO₆/CNTs enhanced the hydrogen generation performance of Mg and increased the initial hydrogen generation rate. The optimal hydrogen generation rate increased to <sc>2172.4 mL g⁻¹ min⁻¹,</sc> and the related activation energy decreased to <sc>23.6 kJ mol⁻¹.</sc> Density functional theory (DFT) calculation found that doped Bi atom enhanced the adsorption of H₂O on Mg and reduced the adsorption of H atom by changing the local charge distribution, thus promoting the hydrolysis reaction.

Evaluating metallic artefact of biodegradable magnesium-based implants in magnetic resonance imaging

Magnesium (Mg) implants have shown to cause image artefacts or distortions in magnetic resonance imaging (MRI). Yet, there is a lack of information on how the degradation of Mg-based implants influences the image quality of MRI examinations. In this study, Mg-based implants are analysed in vitro, ex vivo, and in the clinical setting for various magnetic field strengths with the aim to quantify metallic artefact behaviour. In vitro corroded Mg-based screws and a titanium (Ti) equivalent were imaged according to the ASTM F2119. Mg-based and Ti pins were also implanted into rat femurs for different time points and scanned to provide insights on the influence of soft and hard tissue on metallic artefact. Additionally, MRI data of patients with scaphoid fractures treated with CE-approved Mg-based compression screws (MAGNEZIX®) were analysed at various time points post-surgery. The artefact production of the Mg-based material decreased as implant material degraded in all settings. The worst-case imaging scenario was determined to be when the imaging plane was selected to be perpendicular to the implant axis. Moreover, the Mg-based implant outperformed the Ti equivalent in all experiments by producing lower metallic artefact (p < 0.05). This investigation demonstrates that Mg-based implants generate significantly lower metallic distortion in MRI when compared to Ti. Our positive findings suggest and support further research into the application of Mg-based implants including post-operative care facilitated by MRI monitoring of degradation kinetics and bone/tissue healing processes.

Structure Analysis of Mg-Fe-Graphite/Graphene compounds

It is investigated that the structure of Magnesium (Mg)-based compound containing Fe and graphene (GN) for Mg-based hydrogen storage material, which is one of the most prospective hydrogen storage materials because Mg possesses a larger hydrogen storage capacity (7.6 wt.%). The high dehydrogenation temperature of Magnesium hydride (MgH2) (approximately 450 ℃) should be reduced for a wide range of applications and one of the solutions would be to compound Fe and/or graphene into Mg due to decreasing the binding energy of hydrogen and Mg. Firstly, we prepared less-defected graphene by Salt-assisted Milling - Liquid Phase Exfoliation method (SM-LPE) method and evaluated the number of layers and the crystallinity with Raman spectroscopy. We estimated the GN consists of a single and/or a few layers and has high crystallinity with few defects. Secondly, we prepared the five different compounds of Mg, Fe, Graphite (Gr), and Graphene (GN) by high-energy ball milling and the different milling time. With regard to the compounds, a large amount of amorphous powder was recovered in all of the compounds to which Gr/GN was only added. In terms of the order of addition of Gr/GN, it was confirmed that the Gr/GN adhered to the Mg surface by being added at later milling, and in particular the GN was distributed throughout the sample as nano-particles.

Critical review on development of magnesium alloy as anode inMg‐Airfuel cell and additives in electrolyte

This study aimed to provide a critical review of the magnesium-air fuel cell (MAFC) system to provide readers with an overall comprehension of MAFC, which focuses on the modification of the magnesium anode and properties of saltwater as an electrolyte. Although MAFC is benign to the environment, it is well-known for its challenging corrosion issue and by-product deposition that affect its durability for commercialization and long-term application. Since that MAFC is able to use seawater as electrolyte, it has great potential to be used as an alternative energy option for the marine sector. This journal will dissect the ability of MAFC to be used as a competitive alternative energy. Over the years, researchers have adopted several approaches, such as experimenting with different types of magnesium alloy and anode fabrication techniques, to tackle corrosion problems to alter the microstructure and mechanical properties of the anode in addition to applying a coating protection and using Mg-based composite material. Furthermore, studies intriguingly and gradually focused on electrolyte formulation with different types of additives to address the debilitating precipitation issue and improve the discharge performance. Given the problems that arise in the system, currently, MAFC commercial products are only suitable as emergency back-up power. In future work, an improved storage system for MAFC should be built to accommodate the precipitation products while maintaining the desired cell performance.

Optimizing an Osteosarcoma-Fibroblast Coculture Model to Study Antitumoral Activity of Magnesium-Based Biomaterials.

Osteosarcoma is among the most common cancers in young patients and is responsible for one-tenth of all cancer-related deaths in children. Surgery often leads to bone defects in excised tissue, while residual cancer cells may remain. Degradable magnesium alloys get increasing attention as orthopedic implants, and some studies have reported potential antitumor activity. However, most of the studies do not take the complex interaction between malignant cells and their surrounding stroma into account. Here, we applied a coculture model consisting of green fluorescent osteosarcoma cells and red fluorescent fibroblasts on extruded Mg and Mg–6Ag with a tailored degradation rate. In contrast to non-degrading Ti-based material, both Mg-based materials reduced relative tumor cell numbers. Comparing the influence of the material on a sparse and dense coculture, relative cell numbers were found to be statistically different, thus relevant, while magnesium alloy degradations were observed as cell density-independent. We concluded that the sparse coculture model is a suitable mechanistic system to further study the antitumor effects of Mg-based material.

The Significant Impact of Carbon Nanotubes on the Electrochemical Reactivity of Mg-Bearing Metallic Glasses with High Compressive Strength.

Here, we elucidate the significant impact of carbon nanotubes (CNTs) on the electrochemical behavior of Mg-based amorphous composite materials that were reinforced with CNTs while using pressure die casting. The addition of 3 vol % CNTs led to an increase in the compressive strength of Mg-based amorphous material from 812 MPa to 1007 MPa, and the fracture strain from 1.91% to 2.67% in the composite. Interestingly, the addition of CNTs significantly contributed to the enhancement of corrosion resistance of Mg-based glass by ~30%. The superior mechanical properties are primarily related to the fact that the addition of CNTs hindered the growth of shear bands (cracks), while the high corrosion resistance is related to inferior wettability and the bridging effect between adherent corrosive oxide film and the matrix that provided enhanced corrosion resistance.