Si₃N₄/TaC composite MAO coatings were fabricated by microarc oxidation (MAO) on a Ti–6Al–4V (TC4) alloy in a phosphate-based electrolyte containing Si₃N₄/TaC mixed particles. The influence of the amount of Si₃N₄/TaC particles on the microstructure, composition, tribological behavior, and corrosion properties of the MAO coatings has been investigated. Morphological research of the MAO coatings was carried out using scanning electron microscopy (SEM), with the surface porosity analyzed by ImageJ software. X-ray diffraction (XRD) was used for the detection of the phase characteristic of the MAO coatings, and an abrasive wear test and electrochemical measurements were conducted in the artificial seawater solution by the ball-on-disc friction tester and the electrochemical workstation, respectively. The results showed that Si₃N₄/TaC particles could be successfully incorporated into the composite coatings, and the addition of Si₃N₄/TaC particles greatly reduced the porosity of the coatings, thus improving both tribological and corrosion properties of the composite MAO coatings. The composite MAO coating with the addition of 1 g/L Si₃N₄ + 0.5 g/L TaC particles showed the best tribological property and the optimum corrosion properties.

By contrast with the traditional method of adding hard particles into micro arc oxidation (MAO) coating to improve its wear performance, this study introduced copper into the MAO coating on TC4 alloy by adding copper pyrophosphate to enhance the wear property in a marine environment and the antibacterial property. The results demonstrated that the MAO coating with copper pyrophosphate addition showed a porous structure, and Cu was mainly concentrated around micropores. CuO and Cu₂O were formed in this MAO coating. This MAO coating with Cu had a high bonding strength to the substrate. Although the hardness of the coating with Cu had been reduced, it could reduce the friction coefficient and enhance the wear property in simulated seawater due to the lubrication of Cu. Furthermore, this MAO coating with Cu addition had obvious antibacterial and bactericidal effects due to the antibacterial effect of Cu.

Biomorphic SiC fabric ceramic was synthesised by in situ reactive molten silicon infiltration process using artificial ramie fibres’ template, phenolic resin, and silicon. The phase compositions, microstructure, and physical characteristics of the biomorphic fabric ceramic were characterised and tested. The results show that the final ceramic retains the ramie fabric structure, and presents duplex microstructure including biomorphic SiC fibres and network SiC ceramic around the biomorphic fibres. This biomorphic SiC fabric ceramic is constituted by 95.8% of SiC, has a low density of 1.02 g cm⁻³ and a high porosity of 63.7%, and shows low linear shrinkages and better electrical resistivity along the fibre axis. The uniform and fine SiC particles with the size of ∼4 µm indicate that the reaction–formation mechanism is the dissolution of carbon and the precipitation of SiC, without a second precipitation.

This paper studies the plastic behavior of the ZK61M magnesium alloy through a combination method of experiments and theoretical models. Based on a dog-bone specimen under different loading directions, mechanical tests under uniaxial tension were carried out, and the hardening behavior was characterized by the Swift–Voce hardening law. The von Mises yield function and the pressure-coupled Drucker yield function were used to predict the load–displacement curves of the ZK61M magnesium alloy under various conditions, respectively, where the material parameters were calibrated by using inverse engineering. The experimental results show that the hardening behavior of the ZK61M magnesium alloy has obvious anisotropy, but the effect of the stress state is more important on the strain hardening behavior of the alloy. Compared with the von Mises yield function, the pressure-coupled Drucker yield function is more accurate when characterizing the plastic behavior and strain hardening in different stress states of shear, uniaxial tension, and plane strain tension for the ZK61M alloy.