Kun Qiao

A Study on the Comparison between Different Matrixes Used for Carbon Fiber Reinforced Composite Core

The comparison between carbon fiber reinforced different matrixes composites was studied in this work. Carbon fiber reinforced phenolic resin composite and carbon fiber reinforced benzoxazine resin composite were made by pultrusion processing. Bending strength test and charpy impact strength test were taken to characterize the toughness of different composites, and scanning electronic micro-scopy(SEM) was applied to evaluate the interfacial properties between carbon fiber and different matrixes. It was shown that compared with carbon fiber reinforced phenolic composite, carbon fiber reinforced benzoxazine composite had better performance in toughness and interfacial property. Bending strength and toughness were mainly depending on the property of matrixes, interfacial property was determined by carbon fiber and matrixes.

Application of Acoustic Emission Technology in Material Detection

The principle of acoustic emission (AE) technology was introduced in this work, as well as the application and the achievements of AE in recent years, such as the utilization in unidirectional carbon fiber reinforced composite. References for in-depth research of material properties and failure mechanism were provided in this article.

Effect of Different Layers of Glass Cloth on Carbon Fiber Reinforced Hybrid Composite Core

The effect of different layers of glass cloth on carbon fiber reinforced hybrid composite core is studied in this work. Carbon fiber reinforced hybrid composite of different glass cloth content is made by pultrusion processing. Three point bending test and charpy impact test are taken to evaluate the toughness of different composite, and scanning electronic micro-scopy (SEM) and photograph are carried out to characterize the structure of different composite after destroyed. It is shown that, though at the cost of drop of tensile strength, the increase of glass cloth content in carbon fiber reinforced hybrid composite core improves the flexural strength and impact resistant, and does not affect the microscope destroy pattern and the microscopic structure of failure samples.

The Oxidation Erosion in Carbon Materials for CZ Furnace

In this work, on the basis of carbon materials microstructure and morphology, we study on the influence of carbon fiber content , graphite degree and metal impurities on oxidation performance of carbon materials. The result of oxidation test shows that there are more crystal defects at the interface of carbon fiber and carbon matrix, and oxidation activity of carbon atoms near the area of crystal defects is higher than others.Carbon materials with higher fiber content and higher graphite degree, has a better anti-oxidation performance. The presence of impurities, especially metal impurities play a catalysis role in oxidation of carbon materials. After purification, impurities escape from the graphite microcrystal,resulting that the distortion of lattice decreased, that cause the better anti-oxidation performance.

Surface Modification of Aramid Fiber by NaOH Solution with Different Concentrations

Aramid fiber (AF) was treated by NaOH solution of various concentrations with supersonic vibration at room temperature. The density of NaOH solution was the main parameter. Elongation at break and break strength were tested. The chemical composition of AF was characterized by elemental analysis. The surface of AF was examined by scanning electronic microscopy (SEM). It was shown that elongation at break of treated AF was not decreased, and break strength was a little increased, first increases and then decreases as the concentration of NaOH solution raising. It was also found that the surface of AF after modified was a little rougher. Low concentration of NaOH solution was fit to modify AF.

Study on the Densification Process of the High Density Graphite Materials

The densification process is the key step in the producing of the high density graphite materials. This paper depend on the DSC-TGA analysis of the green petroleum coke to explore the roasting curve. The impregnating process parameters were optimized through orthogonal experimental design. Results show that the green petroleum coke polymerization severe between 200 to 600°C, the coking of volatile has basically completed and the system start densification in 600-850°C.Keeping Nitrogen pressure 1.5Mpa and impregnation temperature 200°Cfor 60min are the first optimization process parameters of impregnation.