Evaluation And Research Of Different Sizes Tow Of Carbon Fiber Properties

Carbon fiber reinforced resin matrix composites have many excellent performance such as lightweight, high strength, wear resistance, corrosion resistance, electrical conductivity and so on, As a new material, Carbon fiber composites have been widely applied in aerospace, sports and leisure, bridges, roads, biomedical and other aspects. However, carbon fiber is an expensive fibrous material, Prices become a major obstacle to widespread use of carbon fiber, large tow carbon fiber can be achieved purposes of reducing the production cost, Therefore, the study of large-tow has great significance. In this paper, the carbon fiber STS40-48 K that produced by Toho and PANEX35-50 K that produced by ZOLTEK and other small-tow carbon fiber are used to study the performance of different tow sizes carbon fiber. The study is mainly from the following aspects:Sizing rate is tested on different tow sizes of carbon fiber. The results showed that domestic carbon fiber sizing rate is generally higher than the rate of foreign carbon fiber sizing. For 12 K carbon fiber, domestic carbon fiber sizing rate higher than 1%, but the foreign carbon fiber sizing rate is generally less than 1%; For different sizes tow of carbon fiber, 3K carbon fiber surface sizing rate is the lowest, but 50 K carbon fiber surface sizing rate is the highest, the sizing rate of other fiber are similar.Analyzing the slurry by infrared spectroscopy, we found that all the carbon fiber surface slurry are epoxy paste except T700SC-12K-F0 E whose slurry is cyclooctanone. The slurry similarity to epoxy of domestic carbon fiber is higher than abroad.The carbon fiber surface morphology before and after desizing found that the roughness is little changed before and after the desizing. Due to the different spinning process, the surfaces are very smooth of the carbon fiber that produced by dry-jet wet spinning process to produce front and rear desizing. However, The surface trench is obvious of the carbon fiber that produced by wet spinning process before and after desizing.Single fiber strength is tested, we found that for 12 k carbon fiber that are produced by different manufacturers at home and abroad, the shape parameter of foreign carbon fiber single fiber strength is generally higher than the domestic carbon fiber shape parameters, which means that the description of single fiber strength of overseas carbon fiber is less than domestic’s, in other words, the stability of foreign carbon fiber is higher than domestic. The scale parameter of foreign carbon fiber single fiber strength is generally higher than the domestic carbon fiber’s, it means that the strength of carbon fiber is higher than the domestic carbon fiber. For different sizes of the carbon fiber tow, The shape parameter of large tow carbon fiber has a more fluctuation than the small tow carbon fiber, it means that large tow carbon fiber stability is better than small-tow carbon fiber.Statistical analysis of carbon fiber surface contact angle, it found that the surface contact angle of large tow was significantly higher than small-tow carbon fiber, it means that the wettability of small-tow carbon fiber is better than large tow carbon fiber. For 12 K carbon fiber in domestic, the contact angle of Zhongfushenying is least, and the contact angle of Zhongjiankeji is largest, in the other words, the wettability of Zhongfushenying is the best.The test of interfacial shear between carbon fiber/resin, we found that the interfacial shear performance of the carbon fiber that is produced by dry-jet wet spinning process is better than which is produced by wet spinning process; the interfacial shear performance of the domestic carbon fiber / resin are generally lower than abroad; the interfacial shear strength of large tow carbon fiber / resin is less than small tow carbon fiber.