Interfacial Structure And Properties Of Carbon Fiber Reinforced Aluminum Matrix Composites Fabricated By Hot Pressing

Carbon fiber reinforced aluminum matrix composites have been widely used in aerospace fields due to the advantages of aluminum and carbon fiber. However, at low temperature non-wetting and interface reaction at high temperature have restricted the development of Carbon fiber reinforced aluminum matrix composites severely. Researchers make efforts to solve this problem through surface modification of carbon fiber and using short fiber, while little research has been done into no coating carbon fiber and carbon fiber woven.Based on this case, Non-coated carbon fiber woven reinforced aluminum matrix composites was fabricated by Hot pressing in this article. Micro structure evolution of the Non-coated carbon fiber woven reinforced aluminum matrix composites after different preparation processes were studied thoroughly by Optical microscopy (OM), X-ray diffraction (XRD), scanning electron microscopy (SEM) and energy spectrum analysis (EDS). The mechanical properties of composites in different conditions were tested. The relations between microstructure evolution and mechanical properties of Non-coated carbon fiber woven reinforced aluminum matrix composites were discussed. The main results can be summarized as follows. (1) Carbon fiber reinforced aluminum matrix composites has been fabricated by using pure aluminum as metal substrate and non-coated carbon fiber woven as reinforcement by Hot pressing at600℃、620℃、640℃and660℃.(2) The microscopic analysis of interface structure of composites fabricated at different temperatures shows that:as the temperature increases, the interfacial bonding state has a parabolic trend and the interface structure is best at640℃. In this preparation process, the composites expose a perfect interface with no macroscopic cracks, holes and other defects on the interface and AI4C3brittle phase is not detected. The interfacial bonding is mainly interfacial diffusion dissolving bonding together with mechanical interlocking supplemented.(3) Through the research of interface bonding and tensile properties of composites fabricated at different temperature, as the temperature rises, the interface bonding and tensile properties increase firstly and then decreases. The comprehensive performance arrive at maximum when the composites fabricated at640℃. The interfacial bonding strength increased of5.43MPa and the tensile strength increased103.5MPa.(4) The tensile properties of composites with different layers shows that: With the increase of fiber layers, the tensile strength of carbon fiber reinforced aluminum matrix composites straight increase, when the fiber layer added to three, the composites tensile strength increased by50.5%, and elongation increased by86.8%.(6) The research of microstructural aspects of fracture surfaces show that: the strength of composites with moderate interface bonding is enhanced by a large number of fibers being pulled out and debonding between the substrate and carbon fibers. However, when the interface combined too strong, the fiber can not be pulled out to absorb the energy consumption, which makes the composites low stress damage, reducing the strength of the composite plate.