Papers by Author: Zong Feng Wang

Abstract: A new glass-ceramic coating material on nickel based super alloy substrate had been found, the glass¬-ceramic coating material was developed from a glass based on MgO–Al2O3–TiO2 system. The coating material was characterized through X-ray diffractometry (XRD), scanning electron microscopy (SEM), differential scanning calorimetry (DSC), hardness, thermal expansion coefficient testing. XRD analysis of the coating materials and the resultant coatings showed presence of a number of microcrystalline phases. SEM micrographs indicated microstructure of the material. Optical micrographs showed smooth glossy impervious free surface with defects. Hardness analysis showed the glass-ceramic coating material had higher microhardness. The thermal expansion coefficient of the nimonic alloy was much higher compared to the coating material at specific temperature.

Abstract: Hybrid friction materials were manufactured with glass fiber, potassium titanate whisker and aramid fiber as reinforcement and the phenolic resin modified by lumbar pericarps oil as matrix material. The effects of load and sliding distance on friction and wear properties were studied by single variable experiments. The worn surfaces of the samples were studied by Scanning Electron Microscope (SEM). The results showed that friction coefficient and wear rate can be significantly increased when the load was increased up to 250N. The friction coefficient varied between 0.25 and 0.3 while the wear rate reduced to 0.49×10^-6 g/(N·m) in the sliding distance longer then 80m. Wear mechanism of samples were to be adhesive and abrasive wear.