In this review article, the methods, such as chemical reduction, deposition-precipitation reduction, chemical vapor deposition, and thermal annealing for the synthesis of intermetallic compounds are briefly described. These different synthesis methods possess intrinsically advantages and shortcomings, therefore, suitable methods may be selected according to the actual requirements in practical applications. Catalytic activities of intermetallic compounds for the reactions of oxidation, hydrogenation, and reforming are summarized, from which it is found that intermetallic compounds are a kind of highly efficient catalytic materials, and their high catalytic performance is associated with the ordered atom arrangement, electronic effect, geometric effect, steric effect, and synergistic action. In addition, the future investigation work on such materials is also envisioned.

Composites of BiOCl-RGO were synthesized via a two-step hydrothermal method. Firstly plain BiOCl was synthesized in the mixed solution of ethylene glycol and deionized water, the acquired nanosphere-like BiOCl of about 400 nm in diameter composed of many nanosheets. Then the RGO carrier was deposited onto the plain BiOCl to prepare BiOCl-RGO nanocomposites. The composites were characterized by Raman spectroscopy, XRD, XPS, SEM and TEM. The photocatalytic property of the composites was evaluated by degrading methyl orange. The results show that the temperature of hydrothermal process significantly affects the photocatalytic property of the composites. The composite of BiOCl -graphene prepared at 140°C shows the highest photocatalytic performance.

High strength Ti-reinforced Cu40Zn brass alloy was prepared by powder metallurgy. The effect of Ti addition on the microstructure, interfacial structure, phase composition and mechanical properties of the brass was investigated. Results show that Ti exists in Cu40Zn matrix as sub-micron Cu₂Ti₄O particles and Ti nanoclusters, which can significantly improve the mechanical properties of Cu40Zn by means of second-phase strengthening, fine-grain strengthening and processing hardening. Cu40Zn-1.9Ti has good comprehensive performance: the yield strength, tensile strength, elongation at break and hardness are 375 MPa, 602 MPa, 17.7% and 163 HV respectively.

Poly-p-phenylene benzobisoxazole (PBO) fibers surface were treated by oxygen dielectric barrier discharge (DBD) plasma to improve the interfacial adhesion between PBO fibers and bismaleimide (BMI) resin. The inter laminar shear strength (ILSS) of PBO/BMI composites greatly increased from 43.9 MPa to 62.0 MPa after oxygen plasma treatment for 24 s with the optimal parameter of 30 W/m³. After oxygen DBD plasma treatment the O content on the surface of PBO fibers increased significantly, but that of N did not change much, even decreased after being overtreated. The content of functional groups -O-C=O group increased from 0 to 3.16%, while the content of -C-O- increased significantly. The oxygen DBD plasma treatment produced a lot of bumps and ravines on the surface of PBO fibers. The surface morphology of the fibers becomes complex and their surface roughness was enhanced to certain extent. The increase of surface oxygen content, as well as the change of surface morphology and roughness are the important reasons for the increase of ILSS value of PBO/BMI composites. In addition, appropriate DBD plasma treatment will not have a significant adverse impact on the tensile strength of PBO fibers, will not affect its role in composite materials.

The effect of residual carbon on the microstructure of the primary and secondary recrystallization of the grain-oriented silicon steel was investigated, whereas, the carbon content of the steel was controlled via varying the steam amount in the gas mixture 25%H₂+75%N₂ for the annealing process. The results show that the average grain size of primary recrystallization decreased and the grain size difference between the surface portion and the center portion increase with the increase of residual carbon content in the steel subjected to decarburization annealing. The texture of primary recrystallization changed from strong {111}<110> or {111}<112> into strong {112}<110> , while the texture of some Goss grains in 1/4 layer or {111}<112> grains was also altered. The steel subjected to high temperature annealing had imperfect secondary recrystallization and bad magnetic properties when the carbon content in the sample was higher than 0.0200%. Phase transformation is the main reason that led to the above phenomena.

The microstructure and performance of a novel DM steel for hot forging dies were systematically investigated by means of scanning electron microscopy (SEM), transmission electron microscope (TEM), X-ray diffractometer (XRD) and thermal fatigue tester. Results show that the laminar M₃C carbides gradually transform into blocky carbides M₇C₃ inside the martensitic slabs, while carbides M₇C₃ and M₂₃C₆ are found at boundaries of slabs. Based on the Uddeholm self-restricting thermal fatigue test results, the short cyclic thermal fatigue performance was controlled by dislocation rearrangement and annihilation. Whereas, the long cyclic one was affected by the temper resistance of the DM steel and strongly depended on the carbide morphology and their resistance to over-ageing. In addition, the free energies of formation for carbides M₃C, M₇C₃ and M₆C in the DM steel are 236.4, 212.0, and 228.9 kJ/mol, respectively. The mechanism of carbides evolution during the thermal stability test is consistent with thermal fatigue test, the transformation of the carbides follows the sequence as M₃C→M₇C₃→M₆C.

The effect of Cu content and sintering temperature on the friction and wear properties of powder-metallurgical Fe-Cu based composites was investigated. The results show that the wear resistance first increases with the increase of Cu content within a range of 20%~60% Cu. Then the wear resistance reaches the optimum with the average friction coefficient of 0.172 and wear loss of 0.007 g for the composite with 40% Cu. However, the wear resistance begins to decrease when the Cu content further increases. Similarly, the wear resistance first increases with the increase of sintering temperature within the range of 1096~1296^oC. Then the wear resistance achieves the optimum with the average friction coefficient of 0.123 and wear loss of 0.0018 g for the composite sintered at 1196^oC. When sintering at higher temperatures, the wear resistance decreases again. During sintering with optimal process parameters, the molten Al may form solid solution with Fe and Cu, which improves the density and strength of the composite. Meanwhile, the decomposition of MnS yields atomic Mn, which mainly forms solid solution with Fe. Also, a part of C in the composite also forms solid solution with Fe. The above facts may in turn generate the solid solution strengthening of the Fe-Cu based alloy. Besides, there exists residual elemental carbon in the Fe-Cu based alloy, which enhances the lubrication of the alloy. After sintering, the grains of Cu become finer presenting as a network in the Fe based matrix. The excellent wear resistance of Fe-Cu based composite can be attributed to the special functions of the individual component of the composite.

The creep deformation behavior and relevant microscopic deformation mechanisms of Ti65 alloy were investigated via tensile creep test by stresses in the range of 120~160 MPa at 600~650^oC and TEM observation. The results show that the primary creep deformation mechanism is dominated by the process of climbing-controlled dislocations crossing the α₂ phases and the creep mechanism in the steady-state creep stage is dominated by the process of diffusion-controlled dislocation climbing at the α/β interfaces, and the stress index of steady-state creep stage varies from 5 to 7. The hindering of dislocation motions by α₂ phases is the dominating process to strengthen the high-temperature creep resistance of Ti65 alloy during the primary creep stage. The silicide precipitates distributed along α/β phase boundaries, impede the dislocation motions and restrict the grain boundary slip (GBS), which is the dominating strengthening mechanism during the steady-state creep stage.