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TiC particles have been synthesized in common straight steels with three different carbon contents by in situ reaction during melting process. Experimental results show that the distribution of TiC particles in the steels containing 0.55 mass%C and 0.8 mass%C is uniform, however, slight segregation of TiC particles has been observed in the steel containing 1.4 mass%C. With the formation of TiC more ferrite precipitates from the steel with 0.55 mass%C, while the TiC formation inhibits the precipitation of secondary cementite in the steel containing 1.4 wt%C. In the present investigation a proper technique of heat treatment has been designed, after which good mechanical properties as well as high wear resistance have been obtained from the steel with TiC additions. However the effect of TiC addition on wear resistance is weakened with the increase of carbon concentration.

The microstructure and localized corrosion behavior of the 7050‐T6 Al alloys treated with different quench transfer time were investigated. Optical microscope observations show that the volume fraction of the recrystallized grains increases slightly with prolonging quench transfer time. Scanning electron microscope observations reveal that the stable η (MgZn2) phase nucleates and precipitates on grain boundaries in the process of transferring to quench. Further observations, using transmission electron microscope, found that the size, nearest neighbor distance, and copper content of the grain‐boundary precipitates increase with quench delay. As a result, the open‐circuit potentials and charge transfer resistance (Rt) of the alloys reduce with increasing transfer time, while the susceptibility to intergranular corrosion (IGC) and strength loss after exfoliation corrosion tests increase sharply. In addition, the IGC network appearance changes from large network to fine network structure, due to the different temperature range where very rapid η phase precipitation takes place between on grain boundaries and on sub‐grain boundaries.

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Mesoporous (MSU) Ce 0.5 Zr 0.5 O 2 mixed oxide with a high specific surface area has been synthesized under weak acidic condition in the presence of an anionic surfactant, sodium dodecylbenzenesulfonate. The effect of the pH value on the formation of mesostructure and the thermal stability of the material has been evaluated. The products were characterized by transmission electron microscopy, powder X-ray diffraction and nitrogen adsorption-desorption measurements. The results showed that the as-prepared Ce 0.5 Zr 0.5 O 2 mixed oxide possessed a specific surface area of 163.3 m 2 •g -1 , which had a cubic fluorite-type structure and possessed specific surface areas of 148.4 and 62.4 m 2 •g -1 after calcination at 500 and 800 ℃ for 2 h, respectively. The material showed excellent thermal stability.

LATP-based composite electrolytes were prepared by sintering the mixtures of LATP precursor and La2O3 nano-powder. Powder X-ray diffraction and scanning electron microscopy suggest that La2O3 can react with LATP during sintering to form fine LaPO4 particles that are dispersed in the LATP matrix. The room temperature conductivity initially increases with La2O3 nano-powder addition showing the maximum of 0.69 mS∙cm−1 at 6 wt.%, above which, conductivity decreases with the introduction of La2O3. The activation energy of conductivity is not largely varied with the La2O3 content, suggesting that the conduction mechanism is essentially preserved despite LaPO4 dispersion. In comparison with the previously reported LATP-LLTO system, although some unidentified impurity slightly reduces the conductivity maximum, the fine dispersion of LaPO4 particles can be achieved in the LATP–La2O3 system.