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To enhance the tribocorrosion properties of chemically bonded phosphate ceramic coating (CBPCC), GO-ZnO was prepared and added into CBPCC. And the tribocorrosion behaviour of CBPCC was investigated. Results show that, with the introduction of GO-ZnO, the open circuit potential of CBPCC shifts in a positive direction and corrosion current density decreases. In addition, the total material loss, the total mechanical wear loss and the total electrochemical corrosion loss of CBPCC all decrease with the increase of GO-ZnO. The wear track of CBPCC after tribocorrosion without GO-ZnO is rough and porous, while the wear track becomes smooth and dense with the incorporation of GO-ZnO. The material in wear track is anchored by GO-ZnO due to the strong bond between GO-ZnO and CBPCC, which decreases the wear loss. Because of the extra force from the tribocorrosion experiment, the material anchored by GO-ZnO forms to a dense structure which prevents electrolyte diffusion into CBPCC. Moreover, GO-ZnO can block the electrolyte diffusion pathway and make it more tortuous. The resistance to the electrolyte diffusion decreases the corrosion current density and the increased wear loss due to electrochemical corrosion.

GO-Al2O3 hybrid material was prepared to enhance the bond strength between GO and chemically bonded ceramic coating (CBCC). TEM and FTIR results indicate that nano Al2O3 is successfully grafted to the surface of GO via chemical bonds. Besides, the tribological behavior of CBCC with GO-Al2O3 hybrid material was investigated. The results show that the friction coefficient and wear rate of CBCC decrease with the introduction of GO-Al2O3 hybrid material. In addition, the formation of debris becomes difficult as the cohesive strength of CBCC increases with the introduction of GO-Al2O3 hybrid material, which can improve the wear resistance of CBCC. Furthermore, because less debris on the worn surface makes bigger real contact surface against the counter ball than that of CBCC without GO-Al2O3 hybrid material, the contact stress obviously decreases, contributing to high wear resistance.

To investigate the mechanical behaviour of graded chemically bonded ceramic coating, four types of ceramic coatings were prepared in this study, and a graded coating was designed using the four coa...

To investigate tribological behavior of graphene reinforced chemically bonded ceramic coatings at different temperatures, tribological tests at room temperature, 200 °C and 500 °C were carried out. Results show that the fracture toughness and the hardness of the coating are improved with the introduction of graphene. Besides, the friction coefficient of the coating decreases with the addition of graphene at the room temperature and 200 °C. The coating without graphene achieves the similar friction coefficient at all temperatures. However, the coating with graphene achieves the lowest friction coefficient at 200 °C, and achieves the highest at 500 °C. In addition, the wear rate of the coating decreases with the increase of graphene. Besides, the wear rate at 200 °C is almost similar with that at room temperature. In contrast, the wear rate at 500 °C is much larger than those at room temperature and 200 °C. The mechanisms for graphene to decrease the friction coefficient and improve the wear resistance of chemically bonded ceramic coatings at evaluated temperatures are clarified.

To solve the heat dissipation problem of high power integrated electronic equipment, a micro heat pipe radiator proposed by the composite plane wall algorithm the thermal resistance has been calculated, an equivalent thermal conductivity of plate heat pipe was determined. The distribution temperature at different heating power was obtained. The comparison was shown that the advantage of heat transfer of the novel micro heat pipe was more visible, and the average temperature of the substrate surface was lower 7 °C than that of the traditional micro heat pipe. By simulation, it was shown that the micro heat pipe effectively diffuses concentrated heat flux and had a proper and uniform temperature characteristic at high heat flux. The variation trend of chip temperature and heat resistance of radiator was carried out by analyzing the effects of heating power on heat transfer performance of the radiator respectively and avoiding the thermal stress concentration of the substrate.

A heat pipe substrate module diffused heat by phase change was designed, and transient thermal properties of the vapor chamber were analyzed. The time of the vapor chamber to get steady-state mainly depends on the heat transfer coefficient. As the heat transfer coefficient increases, the time to reach steady state is shorter. Reducing the temperature drop of the vapor chamber core portion can effectively improve thermal performance for the vapor chamber. The transient temperature rise of vapor chamber tube core is smaller than that of the pure copper substrate module and the air heat pipe substrate module with fixed thermal resistance, it is beneficial to overcome the power “swell” and improve thermal shock resistance of the power device. The thermal resistance of the heat sink accounts for more than 70% of the thermal resistance of the entire heat dissipation module. The transient thermal performance of the vapor chamber and the power module integrated packaged can ensure thermal diffusion efficient and smooth operation.

A kind of novel heat pipe construction was put forward for using solar hot water heating system. An advantage of two-phase heat transfer devices was it can eliminating the entrainment effect because of separated vapor and liquid flow channel. Due to this feature, the novel heat pipe is a perfect product for using the heating systems. But, solar energy utilization is generally restricted by climate factors, leading to overheating in summer and freezing in winter. A new gas–liquid separator type heat pipe heating system based on this problem design is presented. Besides, different types, quantities and area tests were conducted in order to compare the surface temperature of heating concrete block. It indicated that the heat pipe has better thermal conductivity and low thermal resistance. And it can be used to reduce the heating temperature of water, so as to achieve energy-saving purpose. The results show that high-efficiency heat exchanger and rapid thermal response of the copper-water heat pipe heating system. It will be meaningful for improving the thermal efficiency and comfort of the indoor human body, at the same time conducive to safe and efficient operation of the heating system.

The heat pipe radiator has become an effective way to solve the heat dissipation problem of electronic components due to its advantages of good reliability and high-heat dissipation efficiency. So it is necessary to explore the thermal performance of heat pipe radiators.In this paper,gravity radiators with two,four,and six heat pipes are used as the research object.The thermal performance of the three heat pipe radiators with different numbers of heat pipes is compared and analyzed through experiments.It mainly includes the influence of a different number of heat pipes on the heat dissipation power, thermal resistance,temperature uniformity, start-up time and other parameters of the radiator.Research shows that the number of heat pipes is one of the main factors affecting the thermal performance of a radiator. The more heat pipes,the better the thermal performance.

A compact wide passband three-pole LTCC filter is presented; its electrical size is reduced by exploiting quarter substrate integrated waveguide (QMSIW) and eighth-mode SIW (EMSIW) cavities, which is smaller than conversional SIW. The filter is designed on multilayer ceramic, which make the filter further compact. The filter was simulated by full wave simulator. The simulated results show the filter has wide passband, which is centered at 11.2 GHz with 23.6% bandwidth. The volume of the filter is only 8.0×5.0×0.6mm3.