International Journal of Applied Engineering Research issN 0973-4562 Volume 4 Number 10(2009)pp 1939-1954 C Research India Publications http://www.ripublication.com/ijaer.htm Fibre reinforced Composite(frc) structures with Potential Applications: Literature Review Hakim S Sultan Aljibori Mechanical Engineering Department, Faculty of Engineering University Malaya, 50603 Kuala lumpur, Malaysia Abstract Modern technology requires new materials of special properties. One of the reasons for interest in materials of unusual mechanical properties comes from the fact that they can be used as matrices to form composites with other materials of other required properties. After many years of applications, it is interesting to review the present state of a new knowledge and technology of fibre reinforcement composite(FRC) structures. The aim of the paper is to describe the present state of knowledge and technology of FRC and to discuss main directions of their applications. In general, composite and particularly composite with dispersed fibre reinforcement is becoming a high-tech material that provides excellent performance but requires competent design and execution Keywords: Composite Structures, Materials, Fibre and matrix Introduction It is reasonable to begin an introduction to composite materials by defining what these materials are. The term "Composite"refers to an assembly of different materials which when used together; a composite material is defined as a material containing at least two distinct phases on microscopic scale. These are the fibres reinforcing material and the matrix supporting the material [1]. The term"advanced composites refers to the group of materials usually used in the automotive and aerospace industr Composites to be materials in which a homogeneous matrix component is reinforced by a stronger and stiffer constituent that is usually fibrous but may have a particulate or other shape, the term FRC(Fiber Reinforced Composite)usually indicates a thermosetting polyester matrix containing fibers, and this particular composite has the lions share of today's commercial market [2]. The technological advances in various ectors have created demand for newer materials, where they are required to perforn
International Journal of Applied Engineering Research ISSN 0973-4562 Volume 4 Number 10 (2009) pp. 1939–1954 © Research India Publications http://www.ripublication.com/ijaer.htm Fibre Reinforced Composite (FRC) Structures with Potential Applications: Literature Review Hakim S. Sultan Aljibori Mechanical Engineering Department, Faculty of Engineering, University Malaya, 50603 Kuala Lumpur, Malaysia Abstract Modern technology requires new materials of special properties. One of the reasons for interest in materials of unusual mechanical properties comes from the fact that they can be used as matrices to form composites with other materials of other required properties. After many years of applications, it is interesting to review the present state of a new knowledge and technology of fibre reinforcement composite (FRC) structures. The aim of the paper is to describe the present state of knowledge and technology of FRC and to discuss main directions of their applications. In general, composite and particularly composite with dispersed fibre reinforcement is becoming a high-tech material that provides excellent performance but requires competent design and execution. Keywords: Composite Structures, Materials, Fibre and Matrix. Introduction It is reasonable to begin an introduction to composite materials by defining what these materials are. The term "Composite" refers to an assembly of different materials which when used together; a composite material is defined as a material containing at least two distinct phases on microscopic scale. These are the fibres reinforcing material and the matrix supporting the material [1]. The term "advanced composites' refers to the group of materials usually used in the automotive and aerospace industry. Composites to be materials in which a homogeneous matrix component is reinforced by a stronger and stiffer constituent that is usually fibrous but may have a particulate or other shape, the term FRC (Fiber Reinforced Composite) usually indicates a thermosetting polyester matrix containing fibers, and this particular composite has the lion's share of today's commercial market [2]. The technological advances in various sectors have created demand for newer materials, where they are required to perform
1940 Hakim S. Sultan Alibori in stringent conditions, high pressure temperature, highly corrosive environments, which the conventional materials failed to service. This has triggered the development needs for engineered materials to cater to customized needs. Industry has recognized the ability of composite materials to produce high-quality, durable, cost-effective products. In recent years there is an increasing demand in the use of composite materials for the automotive, aerospace and rail industry. The automotive and aerospace applications over the past quarter-century have been primarily in special areas such as energy absorber devices. When using composite in the body structure of a vehicle, considerable weight reductions can be achieved compared to conventional isotropic structures, which leads to reduced fuel consumption and consequently lower carbon dioxide emissions Material Constituents The major constituents in a fiber-reinforced composite material are the reinforcing fibers and the matrix. FRC can be classified into broad categories according to the matrix used: polymer, Metal, ceramic, and carbon Polymer matrix composite include thermoset or thermoplastic resins reinforced with glass fiber, carbon(graphite) aramid(Kevlar), or boron fibers. They are used primarily in relatively low temperature application. Metal matrix composite consists of metal or alloys reinforced with boron, carbon(graphite), or ceramic fibers Composite materials were developed because no single, homogeneous structural material could be found that had all of the desired attributes for a given application in the aerospace industry [3] Ibre One of the most commonly used fibers among the new composite materials is the carbon fiber. Among the advantages of carbon fibers is their exceptionally high tensile strength to weight ratio as well as tensile modulus to weight ratios, high fatigue strength and very low coefficient of linear thermal expansion. Where they can maintain their strength up to 2000oC, thus providing the dimensional stability required in space applications. Due to the high cost of these fibers: they are mostly used in the aerospace industry, where weight saving is more critical than cost. Glass fibers commonly used are the E-glass and S-lass. In addition to these glass types there are others that are not usually included in advanced composites because they are used in different fields. For example, the C-glass: is used for chemical resistance in the manufacture of tanks, ducts, blower hoods, fan housings, and other structures. where resistance to corrosion is required Another new fiber gaining wide acceptance is Kevlar. It also has a unique property to a degree which neither Carbon nor glass fibers have that is adequate fracture toughness. There are two types of Kevlar: Kevlar 29 and Kevlar 49. The Kevlar that usually finds its way into structures is Kevlar 49. It is of equal strength but has a higher modulus than Kevlar 29. Unlike Carbon fibers, Kevlar does not conduct electricity. It also has a low compressive strength and modulus compared to the high tensile properties. Kevlar acts more like a glass fiber to transmit electric radiation such as antenna windows
1940 Hakim S. Sultan Aljibori in stringent conditions, high pressure & temperature, highly corrosive environments, which the conventional materials failed to service. This has triggered the development needs for engineered materials to cater to customized needs. Industry has recognized the ability of composite materials to produce high-quality, durable, cost-effective products. In recent years there is an increasing demand in the use of composite materials for the automotive, aerospace and rail industry. The automotive and aerospace applications over the past quarter-century have been primarily in special areas such as energy absorber devices. When using composite in the body structure of a vehicle, considerable weight reductions can be achieved compared to conventional isotropic structures, which leads to reduced fuel consumption and consequently lower carbon dioxide emissions. Material Constituents The major constituents in a fiber-reinforced composite material are the reinforcing fibers and the matrix. FRC can be classified into broad categories according to the matrix used: polymer, Metal, ceramic, and carbon. Polymer matrix composite include thermoset or thermoplastic resins reinforced with glass fiber, carbon (graphite). aramid (Kevlar), or boron fibers. They are used primarily in relatively low temperature application. Metal matrix composite consists of metal or alloys reinforced with boron, carbon (graphite), or ceramic fibers. Composite materials were developed because no single, homogeneous structural material could be found that had all of the desired attributes for a given application in the aerospace industry [3]. Fibre One of the most commonly used fibers among the new composite materials is the carbon fiber. Among the advantages of carbon fibers is their exceptionally high tensile strength to weight ratio as well as tensile modulus to weight ratios, high fatigue strength and very low coefficient of linear thermal expansion. Where they can maintain their strength up to 2000°C, thus providing the dimensional stability required in space applications. Due to the high cost of these fibers: they are mostly used in the aerospace industry, where weight saving is more critical than cost. Glass fibers commonly used are the E-glass and S-lass. In addition to these glass types: there are others that are not usually included in advanced composites because they are used in different fields. For example, the C-glass: is used for chemical resistance in the manufacture of tanks, ducts, blower hoods, fan housings, and other structures, where resistance to corrosion is required. Another new fiber gaining wide acceptance is Kevlar. It also has a unique property to a degree which neither Carbon nor glass fibers have that is adequate fracture toughness. There are two types of Kevlar: Kevlar 29 and Kevlar 49. The Kevlar that usually finds its way into structures is Kevlar 49. It is of equa1 strength but has a higher modulus than Kevlar 29. Unlike Carbon fibers, Kevlar does not conduct electricity. It also has a low compressive strength and modulus compared to the high tensile properties. Kevlar acts more like a glass fiber to transmit electric radiation such as antenna windows
Fibre reinforced Composite(FRC) Structures 1941 The fiber provides virtually all of the load carrying characteristics of the composite. The desirable characteristic of most reinforcing fibers are high strength, high stiffness and relatively low density. Each type has its own advantages and disadvantages [4]. Unidirectional lamina and typical stacking sequence of composite laminates show in Figures 1 and 2 L Unidirectional continues fiber 圉圉十 Unidirectional Discontinues fiber 屡凌 L Random discontinues fiber Figure 1: Unidirectional Lamina of Composite material Figure 2: Typical Laminates of Composite material Matrix The matrix is essenti binder material of the composite. Basically, the key to composite ures is the resin matrix. The purpose of the composite matrix is to hold the together in the structure unit by virtue of its cohesive and adhesive characteristics, to transfer and distribute the applied load to and between
Fibre Reinforced Composite (FRC) Structures 1941 The fiber provides virtually all of the load carrying characteristics of the composite. The desirable characteristic of most reinforcing fibers are high strength, high stiffness and relatively low density. Each type has its own advantages and disadvantages [4]. Unidirectional lamina and typical stacking sequence of composite laminates show in Figures 1 and 2. Figure 1: Unidirectional Lamina of Composite material. Figure 2: Typical Laminates of Composite material. Matrix The matrix is essentially the binder material of the composite. Basically, the key to producing composite structures is the resin matrix. The purpose of the composite matrix is to hold the fibers together in the structure unit by virtue of its cohesive and adhesive characteristics, to transfer and distribute the applied load to and between Unidirectional continues fiber Bidirectional continues fiber Unidirectional Discontinues fiber Random discontinues fiber
1942 Hakim S. Sultan Alibori fibers, to protect them from environments and external damage, and in many cases contributes some needed property such as ductility, toughness, or electrical insulation. Experimental studies on polymers reveal that matrix behavior is dependent on time of rate and frequency of the load application and the ambient temperature [5-6]. High stiffness and strength usually require a high proportion of fibers in the composite This can be achieved by aligning a large number of fibers into a thin sheet(alumina or ply). The thickness of the lamina is usually in the range of 0. 1 to 1.0 mm. there are many Classification based on Matrices Manufacturing of Composites Various processes have been developed for manufacturing composite materials and composite structures. Composite materials are fabricated using wet lay up, filament winding. Compression molding, injection molding. Pultrusion, Prepreg, resin transfer molding, sheet molding compounds and auto clave molding. The early manufacturing opposites used a hand lay-up technique(Fig 3) Although hand lay-up is a reliable process, it is by nature very slow and labor intensive. In recent years, particularly due to the interest generated in all types of industry, there is more emphasis on the development of manufacturing methods that can support high production rates. This section describes the different processes used to fabricate composites Mold Gel Coat Resin Release Film Reinforcements Figure 3: Hand Lay up Process of Composite Structure Hand lay-up The hand lay-up is the oldest fabrication process for the advanced materials. ( Fig. 3) However, the hand lay-up is the simplest and most widely used fabrication process Essentially, it involves manual placement of dry fibre in the mould or mandrel and succeeding application of resin matrix. Then the wet composite is rolled using the hand rollers to facilitate uniform resin distribution to ensure better interaction between the reinforcement and the matrix and to achieve the required thickness the
1942 Hakim S. Sultan Aljibori fibers, to protect them from environments and external damage, and in many cases contributes some needed property such as ductility, toughness, or electrical insulation. Experimental studies on polymers reveal that matrix behavior is dependent on time of rate and frequency of the load application and the ambient temperature [5-6]. High stiffness and strength usually require a high proportion of fibers in the composite. This can be achieved by aligning a large number of fibers into a thin sheet (alumina or ply). The thickness of the lamina is usually in the range of 0.1 to 1.0 mm. there are many Classification based on Matrices. Manufacturing of Composites Various processes have been developed for manufacturing composite materials and composite structures. Composite materials are fabricated using wet lay up, filament winding. Compression molding, injection molding. Pultrusion, Prepreg, resin transfer molding, sheet molding compounds and auto clave molding. The early manufacturing method for fiber-reinforced composites used a hand lay-up technique (Fig 3). Although hand lay-up is a reliable process, it is by nature very slow and labor intensive. In recent years, particularly due to the interest generated in al1 types of industry, there is more emphasis on the development of manufacturing methods that can support high production rates. This section describes the different processes used to fabricate composites. Figure 3: Hand Lay up Process of Composite Structure. Hand Lay-up The hand lay-up is the oldest fabrication process for the advanced materials. (Fig. 3) However, the hand lay-up is the simplest and most widely used fabrication process. Essentially, it involves manual placement of dry fibre in the mould or mandrel and succeeding application of resin matrix. Then the wet composite is rolled using the hand rollers to facilitate uniform resin distribution, to ensure better interaction between the reinforcement and the matrix and to achieve the required thickness. The
Fibre Reinforced Composite(FRC) Structures 1943 layered structure is then cured In general the hand lay-up fabrication process is divided into four essential steps: mould preparation, gel coating, lay-up and curing Recently, partial automation of the hand lay-up is achieved by spray-up process. In which the application method of the resin matrix is slightly different from hand lay up. The hand lay-up fabrication process is mainly used in the application of marine and aerospace structures [7] A few examples of this processes uses are: boats, portable toilets, picnic tables, car bodies. diesel truck cabs hard shell truck bed covers and air craft skins and interiors. The hand lay-up process is labour intensive plus the plastic resins produce toxic fumes requiring well ventilated facilities and protective equipment for workers Filament windir In a filament winding process, a band of continuous resin impregnated roving or monofilaments is wrapped around a rotating mandrel and then cured either at room temperature or in an oven to produce the final product as shown in Fig 4. The mandrel the applications of filament winding are cylindrical and spherical pressure vessel can be cylindrical, round or any shape that does not have re-entrant curvature. Amor pipe lines, oxygen other gas cylinders, rocket motor casings, helicopter blades large underground storage tanks(for gasoline, oil, salts, acids, water etc. ) The process is not limited to axiS-symmetric structures: prismatic shapes and more complex parts such as tee-joints, elbows may be wound on machines equipped with the appropriate number of degrees of freedom. Modern winding machines are numerically controlled with higher degrees of freedom for laying exact number of layers of reinforcement Mechanical strength of the filament wound parts not only depends on composition of component material but also on process parameters like winding angle, fibre tension, esin chemistry and curing cycle. Typical Properties of Filament Wound Pipes(Glass Fibre reinforced) are listed in Table 2 TRAVERSE CARRIAGE PAY OUT EYE FIBRE SPOOLS Figure 4: Schematic Representation of the Wet Filament Winding Process
Fibre Reinforced Composite (FRC) Structures 1943 layered structure is then cured. In general the hand lay-up fabrication process is divided into four essential steps: mould preparation, gel coating, lay-up and curing. Recently, partial automation of the hand lay-up is achieved by spray-up process. In which the application method of the resin matrix is slightly different from hand layup. The hand lay-up fabrication process is mainly used in the application of marine and aerospace structures [7]. A few examples of this processes uses are: boats, portable toilets, picnic tables, car bodies, diesel truck cabs, hard shell truck bed covers and air craft skins and interiors. The hand lay-up process is labour intensive plus the plastic resins produce toxic fumes requiring well ventilated facilities and protective equipment for workers. Filament Winding In a filament winding process, a band of continuous resin impregnated roving or monofilaments is wrapped around a rotating mandrel and then cured either at room temperature or in an oven to produce the final product as shown in Fig 4. The mandrel can be cylindrical, round or any shape that does not have re-entrant curvature. Among the applications of filament winding are cylindrical and spherical pressure vessels, pipe lines, oxygen & other gas cylinders, rocket motor casings, helicopter blades, large underground storage tanks (for gasoline, oil, salts, acids, water etc.). The process is not limited to axis-symmetric structures: prismatic shapes and more complex parts such as tee-joints, elbows may be wound on machines equipped with the appropriate number of degrees of freedom. Modern winding machines are numerically controlled with higher degrees of freedom for laying exact number of layers of reinforcement. Mechanical strength of the filament wound parts not only depends on composition of component material but also on process parameters like winding angle, fibre tension, resin chemistry and curing cycle. Typical Properties of Filament Wound Pipes (Glass Fibre Reinforced) are listed in Table 2. Figure 4: Schematic Representation of the Wet Filament Winding Process