Structure Design Of Cu-balls Coated Short Carbon Fiber Composite Reinforcement And Performance Study Of The Resin Composite

Due to the excellent mechanical properties, short carbon fiber reinforced resin composite materials are widely used in the national industry fields. However, the weak interfacial bonding between the fibers and the resin, as well as fiber stress concentration, limits its further development. First researchers improved the interfacial performance through surface modification of short carbon fiber, and later a new method of desgining the interfacial shape was introduced. The interfacial shape can be controlled by preparation of the shaped short-fibers. It has been reported that shaped short-fibers can can change the stress distribution and strengthen the interfacial debonding between the fibers and the resin. The shaped short fibers played an important role of reinforcing and toughening composite material. Therefore, study on short-fiber design and preparation is significant for the development of short-fiber reinforced resin composites.In this work, Cu-SCFs composite reinforcements with ball-stick shape were prepared by electrodeposition. And most possible factors of electrodepositing Cu-balls on short carbon fibers were studied. Subsequently, the shaped short-fibers were added into resin matrix to get the shaped interface. Compared with the conventional straight short-fibers, Cu-SCFs had the best reinforcing effect and its composites had the best mechanical properties. Through the observation of fracture surface morphology, the complex fracture behaviors in the Cu-SCFs reinforced resin composites were found, including balls pull-out or at the fracture surface and remaining hole. Mechanical model analysis indicated that, on the one hand, Cu-SCFs weakened stress concentration and generated a more uniform stress distribution; on the other hand, the pull-out resistance of Cu-SCFs was greater than the straight short-fibers and much more energy was needed to destroy composite materials.In addition, because of too many bubbles, nonuniformly distributed short-fibers and less add content of short-fibers, differrent resins and molding methods were applied in the research. Through comparion of various composites in mechanical properties, the best choice was the combination of Cu-SCFs reinforcement, acrylic resin and hot pressing technology.