The wettability of the metal/SiC system is not always excellent, resulting in the limitation of the widespread use of SiC ceramic. In this paper, three implantation doses of Si ions (5 × 1015, 1 × 1016, 5 × 1016 ions/cm2) were implanted into the 6H-SiC substrate. The wetting of Cu-(2.5, 5, 7.5, 10) Sn alloys on the pristine and Si-SiC were studied by the sessile drop technique, and the interfacial chemical reaction of Cu-Sn/SiC wetting couples was investigated and discussed. The Si ion can markedly enhance the wetting of Cu-Sn on 6H-SiC substrate, and those of the corresponding contact angles (θ) are raised partly, with the Si ion dose increasing due to the weakening interfacial chemical reactions among four Cu-Sn alloys and 6H-SiC ceramics. Moreover, the θ of Cu-Sn on (Si-)SiC substrate is first decreased and then increased from ~62° to ~39°, and ~70° and ~140°, with the Sn concentration increasing from 2.5%, 5% and 7.5% to 10%, which is linked to the reactivity of Cu-Sn alloys and SiC ceramic and the variation of liquid-vapor surface energy. Particularly, only a continuous graphite layer is formed at the interface of the Cu-10Sn/Si-SiC system, resulting in a higher contact angle (>40°).

Silicon carbide (SiC) reticulated porous ceramics were prepared by organic foam impregnation, using polyurethane sponges as template and deionized water or alcohol as slurry solvent. The sintering behavior, microstructures and apparent density of struct of the SiC reticulated porous ceramics fabricated using the aqueous slurry under different sintering aids and sintering process and the alcohol slurry were investigated comparatively. The experimental results showed that both the microstructures and apparent density of the samples fabricated by Y2O3+AlN as sintering aid were better than those Al2O3 as sintering aid while the aqueous slurry, and the samples fabricated by two-step process (firstly heated to 700 oC in air furnace, and then sintered at 1800 oC in Ar atmosphere) while Y2O3+AlN as sintering aid obtained the optimal properties. In particular, the samples fabricated by the alcohol slurry and reaction sintering process were provided better properties than the aqueous slurry.

The diamond honing oilstone was fabricated by hot-pressing at 550–650 °C and 25 MPa pressure for 4 min, using Cu–Sn based alloys as binder metal and uncoated or W-coated diamond grains as abrasive material. The microstructures and phase compositions of the honing oilstone were examined and analyzed by SEM and XRD. Effects of the oilstone composition, sintering temperature and volume fraction of diamond grains on the mechanical properties of diamond honing oilstone were investigated. The experimental results show that the interfaces between the diamond grains and metal matrices of all the oilstone samples are smooth and no defects are observed in the metal matrices. The bending strength and rockwell hardness of the honing stones increase with the sintering temperature increasing from 550 °C to 650 °C, and the bending strength decrease with the increase of diamond grains faction. The minimum grinding ratio is obtained as the diamond was W-coated, which can be attributed to the improved interfacial bonding derived from the W coating.

A three dimensional (3D) SiC/Cu-Si composite with bicontinuous structure was fabricated by spontaneous infiltration method, using porous recrystallized SiC ceramic with porosity of 37% as 3D network reinforcement and Cu alloy (Cu-18Si) as matrix. The phase composition, microstructure, and thermo-physical properties of the as-prepared 3D-SiC/Cu-Si composite were investigated. The experimental results showed that the Cu-18Si alloy could fully penetrate into the porous SiC ceramic at 1600 °C for 2 h spontaneously. SiC and Cu15Si4 phases were identified in the as-prepared composites. The interfacial bond between SiC and Cu-Si alloy was tightly and no severe interfacial reaction was observed. The thermal conductivity and coefficient of thermal expansion of the as-prepared 3D-SiC/Cu-Si composite were changed from 89.8 to 55 W·m-1·K-1 and 7.512 to 9.64×10-6 °C-1 with the temperature increased from room temperature to 500 °C, respectively.

The Mo-Ni (Co)-Si metallizing coatings on the SiC ceramic substrate were prepared by vacuum cladding process. The wetting and spreading of molten Al on coated SiC ceramic substrates at 900 oC were investigated by the sessile drop technique, and the interfacial behavior of the Al/coated SiC wetting couples was analyzed. The experimental results showed that the final contact angle of Al/M20NiSi coated SiC was close to 0o. With the increase of Mo content in the Mo-Ni-Si coating, the shape of the sessile drop became very irregular due to the strong interactions between the Al drop and the coating, so it was unable to precisely characterize the contact angles of Al/Mo30NiSi and Al/Mo40NiSi systems. The final contact angle of Al/Mo10CoSi coated SiC system was also close to 0o, however, the final contact angle of Al/Mo20CoSi coated SiC system climbed to ~42o with the Mo content increasing from 10 at.% to 20 at.%. The significant increase of contact angle may be caused by the accumulation of Mo near the triple line which can impede the spreading of Al drop.