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The aim of this study is to investigate the effect of nano-SiO2 (NS) particles addition on physico-mechanical properties, microstructure evolution, and apatite-formation ability of bioactive tricalcium silicate (TCS). Furthermore, the concentrations of calcium (Ca), silicon (Si), and phosphorus (P) in phosphate buffer saline solution (PBS) after immersion of TCS-based cements with diverse additions of NS were also evaluated. The results revealed that the setting time of cement pastes lowered significantly from 72 to 51 min with the doping content of NS from 0 to 5%. The compressive strength and Vickers micro-hardness (HV) of cements with addition of 3% NS after setting for 7 days were significantly higher than those of TCS cements without NS. Furthermore, the cements could induce hydroxyapatite (HA) formation on their surfaces in PBS. The storage solution of TCS-based cements was alkaline, and the pH values changed from 12.26 to 12.65. There were no significant differences about Ca, Si, and P concentrations of PBS after immersion of TCS cement with the addition of 3% NS as compared with doping 0% NS. Our results indicated that TCS cement with addition of 3% NS had enhanced physico-mechanical properties and good HA-formation ability and may make it a potential choice for using as a novel dental material.

Ce3+-substituted Sr-ferrite powder was synthesized through low-temperature calcination ceramic method. The influence of Ce3+ substitution on the microstructure and magnetic properties of Sr-ferrite powder was discussed. Results showed that the Ce3+ ions could completely enter the ferrite lattice when the substitution amount was in the range of x = 0–0.2. The saturation magnetization and intrinsic coercivity of Sr1−xCexFe12O19 ferrites could be enhanced through Ce3+ substitution. These enhancements were attributed to the improvements in the magnetic structure and microstructure.

Cathodic plasma electrolysis (CPE) is used to create surface textures on cast iron samples for improving the tribological properties. Micro craters with confined size distribution were successfully formed by CPE process. These craters can generate extra hydrodynamic pressure that separates two sliding surfaces, increase the oil film thickness and accelerate the transition from boundary to mixed lubrication. It was found that the optimal crater size was 1.7 μm, at which the maximum lubrication efficiency was achieved. The Taguchi method was used to optimize the process parameters (voltage and roughness) for CPE surface texturing. The orthogonal array and the signal-to-noise ratio were employed to study the effect of each process parameter on the coefficient of friction. The results showed that with higher voltage and lower roughness, the lower friction coefficient can be obtained, and thus the lubrication can be more efficiently used for friction reduction.