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Technological developments in the processing of staple carbon fiber disclosed that producing hybrid yarn with improved homogeneity, uniformity, compactness and orientation can fully utilize the potential in high-performance composites. Therefore, developing hybrid yarn structures through yarn formation technology has become an emerging trend in the past few years. The present paper aims to highlight the recent development in the yarn formation technology for producing innovative yarn structures from staple carbon and thermoplastic fibers for high-performance fiber-reinforced plastics. For this purpose, pre-spinning, spinning and post-spinning operations of yarn formation technology are reviewed to technological aspects and processing of staple carbon fiber. Furthermore, recent developments in developing flyer, friction and wrap-spun hybrid yarn for high-performance composites are also presented in this paper. An attempt is carried out to develop the relationship between hybrid yarn structures and composite properties. The comparison of tensile properties of thermoplastic plastic composites shows that composite based on hybrid yarn structure possesses 300% and 700% higher tensile strength compared to nonwovens and injection molding composites. [ABSTRACT FROM AUTHOR]

There is considerable need for research into the application potential of adaptive fiber-reinforced plastics based on shape memory alloys, in particular with regard to industry-specific solutions. Hence, this paper presents the activation time- and voltage amplitude-dependent deformation behavior of adaptive fiber-reinforced plastics incorporating shape memory alloy. In order to attain this goal, shape memory alloy was textile-technically converted into shape memory alloy hybrid yarn using the friction spinning technology. Subsequently, the manufactured hybrid yarn was integrated into the reinforcing fabric in the warp direction using weaving technology. To increase the deformation potential of the adaptive fiber-reinforced plastic, a hinged woven fabric was developed by floating of the warp yarn. The functionalized preform was infused by the Seemann Corporation Resin Infusion Molding Process. Later, an extensive electro-mechanical characterization of the adaptive fiber-reinforced plastic by varying electrical power resulting from the varying voltage amplitude and activation time was completed. The maximum deformation of adaptive fiber-reinforced plastics was achieved at an electrical power of 95 W (50 V/1.9 A) and 60 s of thermal induced activation. [ABSTRACT FROM AUTHOR]

The application of shape memory alloys (SMAs) for the development of adaptive fiber-reinforced plastics has been expanding steadily in recent years. In order to prevent matrix damage and optimize the actuating potential of SMAs during the process of thermally induced activation, a barrier layer between SMAs and the matrix of fiber-reinforced plastics is required. This article approaches the textile technological development of SMA hybrid yarns as a core–sheath structure using friction spinning technology, whereby the SMA serves as the core. Four types of hybrid yarns are produced by varying the number of process stages from one to three, as well as the core and sheath materials. The decoupling of the SMA from fiber-reinforced plastics is crucial for optimizing the actuating potential of SMA, thus it is tested by means of the pull-out test. Although the material loss coefficient increases by raising the number of process stages, the three-stage processing of SMA hybrid yarn with an additional glass roving is found to be the most suitable variation for decoupling SMA from the matrix of fiber-reinforced plastics. [ABSTRACT FROM AUTHOR]

Fiber-reinforced plastics (FRPs) with adaptive properties make lightweight structures feasible that not only possess a high mechanical force absorption but are also able to adapt their mechanical characteristics, such as geometry and rigidity, to external influences. Within the framework of the basic research presented here, new adaptive FRPs are developed on a basis of textile reinforcement semi-finished products integrated with actuators made from shape-memory alloys (SMAs). The realization of adaptive FRPs requires not only knowledge of the material-specific actuatory properties of the functional materials. It also necessitates the development of textile-technical solutions fully exploiting the actuatory potential of the SMAs within the composite. Promising approaches are hybrid yarn structures based on friction spinning technology. In order to reduce the great experimental effort, modeling and simulation of the SMA's material behavior and of the adaptive FRPs' complex composite behavior are carried out by means of finite element methods. It is shown that the developed actuators generate sufficiently high tensions of about 700–800 N/mm2, to bend the FRP specimen up to 45°. [ABSTRACT FROM AUTHOR]