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Natural Fiber Based Bio-materials: A Review on Processing, Characterization and Applications
Published in Didier Rouxel, Sabu Thomas, Nandakumar Kalarikkal, Sajith T. Abdulrahman, Advanced Polymeric Materials, 2022
The pultrusion method has many advantages such as being a low-cost automated system where human involvement is minimal, producing high quality products, high surface finish of the product compared to other composite processing methods, and high production rate as it is a continuous production process. Tapered, complex shapes and thin wall parts cannot be produced by this method.
Characteristics, Fabrication, and Design of Composites
Published in Sherif D. El Wakil, Processes and Design for Manufacturing, 2019
Pultrusion is a fiber-reinforced resin-processing technique that is readily adaptable to the continuous manufacture of constant cross-sectional linear composite shapes. Rods, I-beams, angles, channel beams, and hollow tubes are commonly produced by pultrusion processing. Pultrusion is a linear-oriented processing method whereby yarns of reinforcing fiber are continuously immersed in and impregnated with a catalyzed fluid resin. As the term pultrusion indicates, these resin-impregnated continuous-fiber yarns are concurrently pulled through an elongated heated die designed so that the fiber/resin composite mass exiting the die is sufficiently cured and retains the cross-sectional shape of the die. The apparatus used in the pultrusion process is shown in Figure 9.10. In practice, prescribed lengths of the formed piece can be cut using an in-line cutoff wheel. Pultrusion is, therefore, adaptable to low-cost, continuous production of constant cross-sectional composite shapes. The process of pultrusion is critically controlled by the resin system used (e.g., unsaturated polyester, epoxy, and vinyl ester resins), the temperature and temperature profile of the heated die, and the rate of pulling through the die. You may wonder why these sections would not be produced by forward extrusion, but when you bear in mind that fibers buckle under compression, it would then be easy to realize that it is not possible to push the fibers out of the die orifice while keeping them straight and parallel.
Assessment of Shear Lag in Pultruded GFRP Bridge Decks
Published in Nigel Powers, Dan M. Frangopol, Riadh Al-Mahaidi, Colin Caprani, Maintenance, Safety, Risk, Management and Life-Cycle Performance of Bridges, 2018
Fibre-reinforced polymer (FRP) has relatively high stiffness, strength to weight ratio, and good corrosion resistance. These benefits make it become attractive to meet the increasing demand of high-performance durable materials in civil engineering. To manufacture FRP profiles, a highly automated and continuous manufacturing process known as pultrusion, is considered as the most cost-effective method (Bank 2006). Normally, glass fibres embedded with polyester or vinyl ester resin are used in pultrusion. So far, GFRP has been widely used to as a reinforcing material with concrete and steel to reduce corrosion. In bridge engineering, GFRP hybrid bridge decks or pultruded GFRP sandwich bridge decks have been designed and built for many years. It has been reported by O’Connor and Hooks (2004) that around 83 bridges in United States have been constructed or rehabilitated using GFRP decks. Also, GFRP cable-stayed footbridges were constructed in Scotland and Kolding, Denmark, respectively (Bakis et al. 2002). Furthermore, FRP bridge decks with steel girders have been used on main highway bridge in Netherland (van Ijselmuijden and Tromp 2013).
Multiphase flow simulation in injection pultrusion with variable properties
Published in Materials and Manufacturing Processes, 2020
Fausto Tucci, Renato Bezerra, Felice Rubino, Pierpaolo Carlone
From the very beginning of structural applications of advanced composites, several intriguing challenges, related to process optimization[1,2], Out-of-Autoclave (OoA) curing[3–5], drilling and machining[6–11], surface modification[12–15], to cite but a few, have been successfully faced. Nevertheless, one of the critical issues at the manufacturing stage is still related to the reduction of the void fraction and the creation of a coherent interface (or interphase) between the matrix and the reinforcement.[16] Nowadays, several industries are positively looking at pultrusion processing, among other OoA manufacturing techniques, to produce structural components.[16] Despite the geometrical limitation of pultruded parts, high productivity, excellent mechanical properties, and low costs are promoting the wider application of this process. Pultrusion is characterized by an advantageous flexibility in material selection, since it allows for the utilization of either thermoplastic or thermoset[1,16] resin systems and of different kinds of reinforcement. Recently, a remarkable effort has been directed by researchers to explore the possibility to employ biocompatible materials in order to decrease the environmental footprint.[17–19]
Investigation of 2-step technique for jute fabric reinforced polymer matrix composite
Published in The Journal of The Textile Institute, 2018
Magdi El Messiry, Rania El Deeb
Pultrusion is a continuous molding process using fiber-reinforced in polyester or other thermosetting resin matrixes. Pre-selected reinforcement materials, such as fiberglass roving, mat or cloth, are drawn through a resin bath in which all material is thoroughly impregnated with a liquid thermosetting resin. The wet-out fiber is formed to the desired geometric shape and pulled into a heated steel die. Once inside the die, the resin cure is initiated by controlling precise elevated temperatures. The laminate solidifies in the exact cavity shape of the die, as it is continuously pulled by the pultrusion machine. Fairuz, Sapuan, Zainudin, & Jaafar, 2014; Strong, 2008, showed that the cost of pultrusion production is usually less than the other methods. The objectives of this work were to investigate the factors influence of building the composite through the application of 2-step technique, fabric Pultrusion followed with composite forming, using various polymer /hardener blend ratio.
Short-beam shear fatigue behavior of round curved pultruded composite
Published in Mechanics of Advanced Materials and Structures, 2022
Maikson L. P. Tonatto, José Ricardo Tarpani, Sandro C. Amico
Pultrusion is a commonly used manufacturing technique for composite materials due to precise fiber positioning, high fiber content, low porosity and process automatization. Ordinary pultrusion is known to produce a flat profile as the material is pulled through a stationary die for curing [1–3]. In curved-pultrusion, however, the heated die tool moves back and forth along the profile acting as a reciprocating puller, and a stationary gripper, downstream in the line, opens and closes as programmed. This allows the material to be pulled around a curve.