The curing behavior of a fiber-reinforced polymer composite part is interesting for both the industrial and scientific community, for it is related to process optimization, quality upgrade, and material characterization. The study at hand focuses on the potential of temperature measurements as a means to monitor curing; kinetic analysis which conventionally is being done for small neat resin samples in a thermally stable environment (laboratory instruments), is in this study implemented for actual scale composite samples in an environment with significant thermal gradients (manufacturing). To ensure the success of this transition, live temperature data and kinetic parameters derived from DSC of composite samples were used as input to the kinetic equations. Process monitoring with thermocouples that was compared with dielectric constant monitoring and conventional kinetic analysis confirmed the validity of the method. An application with infrared thermography determined the impact of heat insulators within the composite (e.g. delaminations) on the superficial curing degree.

Thermoplastic tapes have found a prominent place in automated tape placement (ATP), due to their reduced processing time. ATP also offers significant reduction in labour; however, the most attractive aspect is the use of its welding properties. Welding or diffusion bonding is necessary for two thermoplastic materials to bond to each other through the combined effect of heating and consolidation pressure. The work published in this article shows how various thermoplastic tape materials with different material properties are bonded to each other using a direct flame-type ATP process. Contact angle and differential scanning calorimetry measurements help understanding of the processing needs of the considered materials. The samples obtained after ATP are sent for peel testing using a wedge peel test principle, so that the force required to separate the bonding is identified. A T-peel test/pull test is also employed to cross-compare peel results obtained through wedge peel testing. The main aim of the work is to study the quality of connection between the two plies with different material interfaces and also how friction might contribute to peel force when wedge peeling is used. A numerical model is also implemented to show the effects of this friction.

Binder applications have found their place in liquid composite molding processes, as they simplify preprocessing steps such as preforming and subsequent handling. Moreover, binders can modify mechanical behavior of finished fiber reinforced plastic parts. Besides the obvious potentials, topics such as the impregnation behavior become more complicated due to binders. The present paper addresses the issue of estimating permeability values of epoxy powder bindered non-crimp fabrics, after considering different test fluids and their behavior under standard laboratory conditions as well as manufacturing-oriented conditions. Test fluid properties, especially surface energy as well as viscosity development with respect to temperature were provided, thereby highlighting a more complete picture of the flow situation during resin transfer molding processes. In contrary to former scientific studies, the influence of test fluids seems to have more influence when investigating Bindered Preforms.

The importance of preforming techniques is constantly increasing due to the fast development of liquid composite moulding processes. Besides traditional preforming methods such as tufting and stitching, tackifier based methods have developed rapidly. This paper presents a new methodology utilising 3D-printer technology for fabrics, through preform manipulation and thus enabling in-plane permeability property customisation. Two patterns of 45° and 90° with respect to the predominant permeability direction were printed onto the fabric consisting of parallel thermoplastic polymer melt strands. After a hot pressing stage the resulting preforms were characterised in terms of their in-plane permeabilities with an optical permeameter and compared to the original material's permeabilities. Furthermore a parameterised model is proposed describing the phenomena causing the manipulation by introducing a scale matrix for translating the original material's permeabilities into the permeabilities of the manipulated preforms.

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