| This dissertation is composed of two parts: study on the forming processing of Poly Aryl Ether Ketone matrix thermoplastic composites, and study on the fusion bonding technologies.In the first part, Ring-Opening Polymerization of cyclic poly aryl ether ketone and its application in forming carbon fiber reinforced thermoplastic composites have been investigated firstly. The melt viscosity of the cyclic oligomer is very low which is necessary to impregnate the carbon reinforcement well. K2CO3 is chosen as catalyst which is accessible and nontoxic. In order to distribute the catalyst homogeneously in the oligomer, K2CO3 powder is mechanically pre-mixed with the oligomer and then uniformly sprayed on the carbon reinforcements which are compression-molded to make composite laminates on hot-press via the ring-opening polymerization. As a control, the carbon reinforcements are also immersed in an aqueous solution of K2CO3 for surface impregnation firstly, and then dry-sprayed with pure oligomer and also compression-molded by a similar manner, which gets higher mechanical properties. The results indicate that the ring-opening polymerization method is useful and effective to forming thermoplastic composites, but still a long way to practical applications.Second, the thermoplastic forming and crosslinking treating processing of the Controllable Crosslinking Poly Aryl Ether Ketone (CCPAEK) matrix composites is studied. The Melt Index data show that the fluidity of CCPAEK is enhanced quickly at about 340℃. It contains active groups and can be crosslinked by heating or irradiation methods. But heating treatment reduces the mechanical properties of the thermoplastic composite for complex subsidiary reactions. The Electron Beam irradiation characters of the CCPAEK are studied and the thermoplastic composite specimens are EB irradiated at a certain dosage. The influences of EB irradiation on the structure and properties of the composites are studied. The glass transition temperatures (Tg) of the irradiated couples are found enhanced limitedly by means of Differential Scanning Calorimeter (DSC) and Dynamic Mechanical ThermalAnalysis (DMTA). The flexural strength of EB treated specimen increases while the flexural module and the short beam shear strength change unobviously. From Scanning Electron Microscope (SEM) photos it is found that the irradiation has almost no influence on the interfacial structures of the composites.The third, processing of thermoplastic blends matrix composites is experimentally investigated. The methods and theories of polymer blends are introduced into preparation of thermoplastic prepregs and composites. Nanocaly is used as modifier to control the content of thermoplastic matrix in winding process to prepare prepregs. The mechanical properties of blends matrix composites approach those of monocomponent PEEK matrix composites, and the glass transition temperatures of blends matrix composites are enhanced obviously. The processing of thermoplastic blends matrix composites is rather simple and versatile to different purposes and systems.In the second part, the resistance implant welding of thermoplastic composites is studied. The carbon fiber reinforced thermoplastic prepregs are used as resistance implant heating elements. The results show that the 3085/PEK-C prepreg heating elements have uniform conductivities and good single-layer heating ability. It is also founded that the directions of the unidirectional heating element prepregs influence the strength of welds. Because of the nonhomogeneity of resistance implants, the welding strength is limited.The thermoplastic composites inherit electroconductivity from carbon fiber reinforcement to a certain extent. Therefore the thermoplastic composites themselves could act as heating elements for self-resistance welding. The experimental results show that the contact resistance between carbon fibers is the main part of the total transverse resistance of the composite laminates, which is influenced by the processing conditions and fiber...
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