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Modification of bioceramics by ion implantation of magnesium (Mg) is of interest as Mg is the fourth abundant cation in the human body. In this work, magnesium was ion-implanted into a ZrO₂ based bioceramic stabilized with Y₂O₃ and Al₂O₃. Both Mg-implanted and unimplanted samples were soaked in a simulated body fluid (SBF) for a period of time. The deposits on the surface of various samples were characterized with scanning electron microscope (SEM), X-ray diffraction (XRD), and Fourier transform infrared spectroscopy (FTIR). We find that the Mg-implanted ZrO₂ shows better bioactivity than the plain bioceramic. These results indicate that Mg-implantation can improve the bioactivity of the ZrO₂ based bioceramic. Mechanisms governing the improvement are discussed in this paper.

AZ91D magnesium alloys with and without dispersed SiC particles were oxidized between 420 and 500°C in air. They oxidized to fine MgO oxide grains containing dissolved ions of Al. Their oxidation rates increased almost linearly, with an increase in the oxidation temperature and time. SiC particles did not oxidize during oxidation, and increased the oxidation resistance of the alloy through diminishing the exposed surface area. With the increase in the amount of the dispersed SiC particles from 5 to 10, and to 20 wt.%, the oxidation resistance progressively increased.

The need of engineered materials with high strength to weight ratio was instrumental for the development of a novel magnesium metal–metal composite with the addition of titanium (reinforcement) and aluminum (alloying element) through disintegrated melt deposition technique. The X-ray diffraction analysis and scanning electron microscopy analysis used to explore the metallurgical insights of the developed magnesium metal–metal composite. Wear tests were carried out with pin-on-disc equipment by varying the input parameters load and sliding velocity over a sliding distance of 2000m. Wear was obtained as the output from the experiments, and the same was analyzed through Pareto analysis of variance, to identify the significant parameters. Also, a fuzzy logic-based model was developed to predict the wear behavior of the metal–metal composite. The wear mechanisms involved in the dry sliding wear behavior were analyzed through worn surface analysis and wear debris analysis.

Magnesium is reinforced with three different weight percentages (5%, 10% and 15%) of SiC particles (200 mesh size) by stir casting technique to fabricate Mg/SiC_p composites. The Scanning Electron Microscope (SEM) images, micro and macro hardness of three different composites are investigated. The comparison of micro and macro hardness clearly shows that increase in the weight percentage of SiC contributed to increase in hardness. However, uniform dispersion of SiC can be achieved while adding 5% SiC in the composite. Then, the Box Behnken experimental design in response surface methodology is employed for machining 3mm diameter hole in the Mg/SiC_p samples using EDM. The second-order model for Material Removal Rate (MRR) and Tool Wear Rate (TWR) are developed with the influencing parameters of weight percentage of SiC, current, pulse on time and pulse off time. The parameter optimization yields maximum MRR and minimum TWR.

In this work, the dry sliding wear behaviors of pure monolithic magnesium and magnesium–titanium dioxide (Mg–TiO₂) composites were studied using pin-on-disc tribometer against an oil-hardened nonshrinking die steel (OHNS) counter-disc with a normal load of 0.5–2kg and a sliding velocity of 1.5–2.5$\mathrm{\text{m}}\cdot {\mathrm{\text{s}}}^{-1}$ with the sliding distance and wear track diameter of 1500m and 90mm, respectively. The pin samples were characterized for their microstructural, nanomechanical and tribological properties such as wear rate, coefficient of friction and wear fractographs. Scanning electron microscopy (SEM) was used to analyze the worn-out surfaces of each pin sample in order to identify the different types of wear and wear mechanisms and the chemical constituents of each element were quantified by energy-dispersive spectroscopy. The influence of TiO₂ reinforcements on the nanomechanical behavior was studied by nanoindentation technique. As compared with pure Mg, the nanoindentation strengths of Mg–1.5TiO₂, Mg–2.5TiO₂ and Mg–5TiO₂ composites were found to increase by 11.9%, 22.2% and 35.8%, respectively, which was due to the addition of TiO₂ particles and also due to the good bonding at the interface of TiO₂ and magnesium particles. From the wear test results, a significant change in wear rate was observed with the change in normal load than that of sliding speed, whereas a significant change in coefficient of friction was noticed with the changes in both normal load and sliding velocity. The dominant wear mechanisms involved under the testing conditions were identified through plotting the contour maps and SEM fractographs. Also, from the fractographs it was noticed that delamination and plowing effect have been the significant wear mechanisms observed during low wear rate of samples, whereas melting, delamination and oxidation wear have been observed during high wear rate of pure Mg and its composites.

The current scenario focuses on lightweight and better energy-absorbing structural materials for critical engineering applications in aerospace, automobiles, marine, electronic, and implant materials for biomedical industries. The magnesium-based syntactic foams are the preferred choice of material in the same category due to their lightweight, higher plateau strength, better damping characteristics, and excellent energy absorption behavior. Many works were reported based on the polymer and aluminum-based syntactic foams and their developments. However, the rapidly increasing interest in magnesium-based syntactic foams and the adoption of the applications are still at a nascent stage. This proposed review work comprehensively insights the magnesium-based syntactic foam; various hollow filler material usages and summarizes the influence of physical and mechanical behavior on processing routes and future research opportunities for applications.

The present study proposes a constitutive model for deformation twinning which takes into account the twin degrees of freedom via incompatibility tensor model based on Field Theory of Multiscale Plasticity (FTMP). The model is introduced in the hardening law in the FTMP-based crystalline plasticity framework, which is further implemented into a finite element code. Deformation analyses are made for pure single crystal magnesium with HCP structure, and the descriptive capabilities of the proposed model are confirmed based on critical comparisons with experimental data under plain–strain compression in multiple orientations, available in the literature. The simulated results are demonstrated to successfully reproduce the unique stress–strain responses induced by twinning. The evolution of the relative activities of the various slips, and twin mechanisms for each orientation are extensively examined.