FEM Analysis of Textile Reinforced Composite Materials Impact Behavior

Composite materials reinforced with textile fabrics represent a complex subject. When explaining these materials, one must consider their mechanical behavior in general, and impact resistance in particular, as many applications are characterized by dynamic strains. Impact characteristics must be considered from the early stages of the design process in order to be controlled through structure, layer deposition and direction. Reinforcement materials are essential for the quality and behavior of composites, and textile reinforcements present a large range of advantages. It takes a good understanding of the requirements specific to an application to accurately design textile reinforcements. Currently, simulations of textile reinforcements and composites are efficient tools to forecast their behavior during both processing and use. The paper presents the steps that must be followed for modelling the impact behavior of composite materials, using finite element analysis (FEM). The FEM model built using Deform 3D software offers information concerning the behavior structure during impact. The behavior can be visualized for the structure as a whole and, for different sections, be considered significant. Furthermore, the structure’s strain can be visualized at any moment. In real impact tests, this is not possible due to the very short time interval and the impossibility to record inside the structure, as well as to record all significant stages using conventional means.

Friction Characterization of UHMWPE Cross-Ply Composite Sheets for Thermoforming Processes

Thermoforming is an attractive process for the low-cost high-volume manufacture of textile-reinforced composite structures with complicated geometries. Tool/ply and ply/ply frictions play critical roles during forming. The friction between the binder ring and the blank induce an in-plane tensile stress that mitigates wrinkling. Unwanted wrinkling can develop across the part if the in-plane stresses are too low but tearing of the material can occur if the applied stresses are too high. Understanding the role that friction plays during thermoforming can give insight on how to mitigate these manufacturing-induced defects in the part. In the current work, the coefficients of friction for two unidirectional cross-ply ultra-high molecular weight polyethylene (UHMWPE) materials are characterized as a function of pressure, fiber orientation, side of material, and pulling rate for [0/90/0/90] cross-ply sheets. The materials are tested at multiple fiber orientations to understand the influence that fiber direction has with respect to the coefficients of friction and on each respective side of the material to understand how surface topology influences the coefficients of friction. The results of the testing are found to correlate with modified Hersey numbers.

Unstructured Uncertainty Based Modeling and Robust Stability Analysis of Textile-Reinforced Composites with Embedded Shape Memory Alloys

This paper develops the mathematical modeling and deflection control of a textile-reinforced composite integrated with shape memory actuators. The mathematical model of the system is derived using the identification method and an unstructured uncertainty approach. Based on this model and a robust stability analysis, a robust proportional–integral controller is designed for controlling the deflection of the composite. We showed that the robust controller depends significantly on the modeling of the uncertainty. The performance of the proposed controller is compared with a classical one through experimental analysis. Experimental results show that the proposed controller has a better performance as it reduces the overshoot and provide robustness to uncertainty. Due to the robust design, the controller also has a wide operating range, which is advantageous for practical applications.

Sustainable mineral coating of alkali-resistant glass fibres in textile-reinforced mortar composites for structural purposes

The mechanical performance of a silica-based mineral nano-coating applied to alkali-resistant glass textile-reinforced composite materials aimed at structural strengthening is investigated experimentally. The silica nano-film is directly applied to the alkali-resistant glass fabric by sol–gel deposition. Two lime mortars are adopted as embedding matrix, which differ by the ultimate compressive strength and elongation. Uni-axial tensile tests of prismatic coupons are carried out according to the ICC AC434 guidelines. Remarkable strength and ductility enhancements could be observed in the silica-coated group, as compared to the uncoated group, for both mortar types. Digital image correlation, electron scanning and optical microscopy provide evidence of improved interphase strength. X-ray diffraction of the anhydrous mortars brings out the role of the mineralogical composition of the embedding media on the overall bonding properties of the composites. Consideration of design limits and energy dissipation capabilities reveals the crucial role of matrix ductility in bringing the contribution of interphase enhancement to full effect. We conclude that best performance requires optimizing the pairing between fabric-to-matrix adhesion and matrix ductility.

Experimental Analysis and Simulation of Novel Technical Textile Reinforced Composite of Banana Fibre

The use of natural fibres allows reducing environmental impact, due to their natural renewable origin and the lower energy needed for their production and processing. This work presents the mechanical characterization of a newly developed technical textile, with banana fibre treated by enzymes, comparing experimental results with numerical simulation based on the definition of the unit cell at micromechanical level. The experimental test shows that the composite with the fabric of banana fibre presents worse mechanical behaviour than the one with commercial flax fibre. The presence of wool, necessary for producing the yarn, reduces the mechanical properties of the banana textile. The numerical simulation had an acceptable error compared with the experimental results, with a global average error of 9%, showing that the predictive modelling based on the multiscale method is suitable for the design process of this kind of composite.

Textile-Reinforced Composites for the Automotive Industry

In the last decades, automotive industry has especially focused on developing and applying new materials and technologies for enhancing the comfort and security levels in the vehicles, but on the other hand for reducing the weight of the means of transportation in order to decrease the energy consumption. In this concept, textile-reinforced composite structures come in possession of one of the most favored materials in the automotive industry by satisfying these demands. In this chapter, usage of textile-reinforced composites in the automotive industry has been elucidated under three main sections: textile reinforced composites for 1) automobiles, 2) mass transportation vehicles, and 3) trucks. The aim of this chapter is to discuss the subject in detail by giving technical information about particular vehicle parts and composite structures utilized in the automotive industry and academia.