Thursday, July 25, 2019
Fibre Reinforced Plastics Essay Example | Topics and Well Written Essays - 3000 words
Fibre Reinforced Plastics - Essay Example These set of additions impart a new identity to the composite in terms of heat resistance, strength and stiffness. Individually the mechanical properties of these additives might not be of an appreciable value but on combining to form a composite matrix these properties are magnified. The ultimate mechanical property of the composite of course depends upon the manner in which these fibres are arranged in the matrix and the manufacturing method followed in producing the composite. Both these applications; Aerospace and Formula-1 deal with mechanisms to reduce the weight of the body and increase the aerodynamic profile of the surface. These functions would ultimately define the fuel efficiency and the speed of the aircraft or the Formula-1 car. (Cripps David, 2000) Research currently being undertaken seeks to refine the existing manufacturing processes to reduce the weight of the composite further but at the same time maintaining structural integrity. Advantages of using FRP 1. This of fers a wide range of corrosion resistance over acids, chlorides and other oxidizers. 2. Since its offer no galvanic potential it negates the requirement of sacrificial anodes for cathodic protection. (The composite advantage, 2004) 3. The strength to weight ratio is quite large. 4. It can operate over a wide range of temperatures; from low temperature cryogenic temperature applications to high temperatures in the range of 350 to 400? F. (The composite advantage, 2004) 5. It provides safe working environment as it is fire resistant. 6. The inherent nature of the material and the adaptability of the manufacturing process make it suitable for creating large complex shapes in situ. 7. Both the installation costs and maintenance costs are lower. (The composite advantage, 2004) The Manufacturing Process There are number of manufacturing processes that are used in producing Fibre Reinforced Plastics. These include the 1. Hand Lay-Up process 2. Spray Lay-Up process 3. Vacuum Bagging 4. Fila ment Winding 5. Pultrusion However the manufacturing process that is usually used in the manufacturing of components and structural parts of aircrafts and F1 racing cars include the following (Cripps David, 2000) 1. Resin Transfer Molding (RTM) 2. Vacuum Assisted Resin Transfer Moulding (VARTM) 3. Prepegs 4. Resin Film Infusion. (RFI) 1. Resin Transfer Moulding (RTM) - This is a closed moulding process done under low pressure. The volume of composite produced is somewhere between that generated in a contact moulding process and that of a compression moulding process. The strands of reinforcement that is completely dried out are neatly arranged in the lower part of the mould. Glass reinforcements of various shapes can also be used along with the fiber matrix to ensure that complex mould shapes can be generated. Source: Cripps David, 2000, Reinforced Transfer Moulding The mating part or the upper portion of the mould is then closed onto the bottom half of the bold leaving a cavity whi ch eventually takes the shape of the structure this process is trying to manufacture. The thermosetting resin is then injected into this cavity space. It is necessary to ensure that sufficient amount of this resin is used to avoid the formation of voids, cavities or edge imperfections caused due to low quantity of resin. (Rice Brian and Lee William, n.d ) To assist in this filling process and guarantee that all areas of this cavity are filled, vacuum can be used which draws the resin to all parts of the cavity and ensures a perfect fill. This process is also known as the Vacuum Assisted R
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