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The infiltration casting method is used for the preparation of three-dimensional co-continuous network structure of graphite/cast steel composite material in atmospheric pressure. Using modal analysis method, flake graphite cast iron specimen and composite sample are compared about damping factors. The results show that amplitude attenuation of the composite material is more quickly than that of flake graphite cast iron specimens. Supported in two rigid points state, the first step damping ratio of the composite material is 2.1 times of flake graphite cast iron. At the same time, its tensile strength is 1.54 to 1.68 times that of flake graphite cast iron, its hardness reaches more than 86%, and its bulk density is reduced to less than 94%. The composite not only has good vibration damping and anti-friction performance, but also has comprehensive mechanical properties exceeding the level of flake graphite cast iron. It is possible to replace flake graphite cast iron for manufacturing important mechanical equipment castings such as fuselage and guide rail to obtain better anti-wear / vibration damping effect.

The infiltration casting method is used for the preparation of three-dimensional co-continuous network graphite / cast steel composite material in atmospheric pressure. The friction and abrasion behavior of composite specimen in condition of dry sliding friction are investigated by peg-tray friction abrasion tester. The anti-wear mechanism of composite material is discussed. The results show that the relative wear resistance of the composite material is 6.5～7.1 times of graphitic cast iron, and average friction coefficient is 60.5～73.3% of graphitic cast iron. The composite material provides with good self-lubricating and anti-friction property in condition of dry sliding friction.

Melt electrospinning, a technique that has gained increasing attention since it easily can generate continuous ultrafine fibers directly from polymer melts without the use of any solvent. Therefore, it is considered as a safe, cost effective, and environmental friendly technique. However, with all those great advantages, the technique still suffers some drawbacks such as: large fiber diameter and low throughput. The hot air assisted melt differential electrospinning (MDES) is a new technique invented by our research team that can solve or eliminate those drawbacks. The most important features of our used apparatus are: Needleless nozzle that could generate multiple Taylor cones around the bottom edge of the nozzle, which can result in a high throughput. The stretching force acting on the jets can be further strengthened by an air current provided by an air pressure gun. Interference between the high voltage supply and temperature sensors could be prevented through the grounding of the nozzle. The ultrafine pp webs produced using the same apparatus was in the micro/nano scale with a diameter of 600nm-6um and a smooth surface. Porosity of the webs ranges from 86.5%-99.4% when different collecting devices are used. The resultant ultrafine webs were applied in three areas: oil sorption, water treatment, and hydrophilic PP membrane. The results were very promising as for oil the sorption capacity was 129.0g/g; for water treatment, the rejection rate for 3um particles was 95%. And for the hydrophilic PP membrane, the water sorption capacity was 12.3 g/g.