Chapter 1:Introduction to Composite Materials /25 Many of the world's roads and bridges are badly corroded and in need of constant maintenance or replacement. Composites offer much longer life with less maintenance due to their corrosion resistance. Repair,upgrading,and retrofit of bridges,buildings,and parking decks Fig.1.30 Infrastructure applications filament winding for golf shafts.Lighter,stron- forming is a snowboard,which typically involves ger skis and surfboards also are possible using the use of a sandwich construction (composite composites.Another example of a composite ap- skins with a honeycomb core)for maximum spe- plication that takes a beating yet keeps on per- cific stiffness
Chapter 1: Introduction to Composite Materials / 25 Fig. 1.30 Infrastructure applications filament winding for golf shafts. Lighter, stronger skis and surfboards also are possible using composites. Another example of a composite application that takes a beating yet keeps on performing is a snowboard, which typically involves the use of a sandwich construction (composite skins with a honeycomb core) for maximum specific stiffness
26/Structural Composite Materials Corrosion resistance also offers the construction industry advantages Shown here:Pultruded fiberglass rebar strengthens concrete:fiberglass is also used in some shingling material With the number of mature tall trees dwindling,the use of composites for electrical towers and light poles is greatly increasing. Fig.1.31 Construction applications Although metal and ceramic matrix com- are used where high temperatures are involved. posites are normally very expensive,they have However,the much higher temperatures and found uses in specialized applications such pressures required for the fabrication of as those shown in Fig.1.34.Frequently,they metal and ceramic matrix composites lead
26 / Structural Composite Materials Although metal and ceramic matrix com posites are normally very expensive, they have found uses in specialized applications such as those shown in Fig. 1.34. Frequently, they are used where high temperatures are involved. However, the much higher temperatures and pressures required for the fabrication of metal and ceramic matrix composites lead Fig. 1.31 Construction applications With the number of mature tall trees dwindling, the use of composites for electrical towers and light poles is greatly increasing
Chapter 1:Introduction to Composite Materials /27 Composites are being used for wind turbine blades to improve energy generation efficiency and reduce corrosion problems. Fig.1.32 Composite clean energy generation to very high costs,which severely limits their tance.They are used in aerospace,automotive, application. marine,sporting goods,and,more recently,infra- Composites are not always the best solution. structure applications.The major disadvantage An example is the avionics rack for an ad- of composites is their high cost.However,the vanced fighter aircraft shown in Fig.1.35.This proper selection of materials(fiber and matrix). part was machined from a single block of alu- product forms,and processes can have a major minum in about 8.5 hours and assembled into impact on the cost of the finished part. the final component in five hours.Such a part made of composites would probably not be cost competitive. REFERENCES Advanced composites are a diversified and growing industry due to their distinct advantages 1.M.E.Tuttle,Structural Analysis of Poly- over competing metallics,including lighter meric Composite Materials,Marcel Dekker, weight,higher performance,and corrosion resis- Inc.,2004
Chapter 1: Introduction to Composite Materials / 27 Fig. 1.32 Composite clean energy generation to very high costs, which severely limits their application. Composites are not always the best solution. An example is the avionics rack for an advanced fighter aircraft shown in Fig. 1.35. This part was machined from a single block of aluminum in about 8.5 hours and assembled into the final component in five hours. Such a part made of composites would probably not be cost competitive. Advanced composites are a diversified and growing industry due to their distinct advantages over competing metallics, including lighter weight, higher performance, and corrosion resistance. They are used in aerospace, automotive, marine, sporting goods, and, more recently, infrastructure applications. The major disadvantage of composites is their high cost. However, the proper selection of materials (fiber and matrix), product forms, and processes can have a major impact on the cost of the finished part. References 1. M.E. Tuttle, Structural Analysis of Polymeric Composite Materials, Marcel Dekker, Inc., 2004
28 Structural Composite Materials Composites improve the performance of sports equipment. Fig.1.33 Sporting goods applications Metal Matrix Composite Metal Matrix Composite Electronic Components Structural Components Carbon-Carbon Brakes Ceramic Matrix Ceramic Exhaust Nozzles Fig.1.34 Metal and ceramic matrix composite applications
28 / Structural Composite Materials Fig. 1.33 Sporting goods applications Fig. 1.34 Metal and ceramic matrix composite applications
Chapter 1:Introduction to Composite Materials /29 Number of Pieces......6 Number of Tools...........5 Design and Fabrication hr (Tools).........30 Fabrication hr..8.6 Assembly Man-hours....5.3 Neight(b）.8.56 Fig.1.35 Composites are not always the best choice.This avionics rack machined from an aluminum alloy block would not be cost-competitive if made of composites.Source:The Boeing Company 2.M.C.Y.Niu,Composite Airframe Struc- SELECTED REFERENCES tures,2nd ed.,Hong Kong Conmilit Press Limited,2000 High-Performance Composites Sourcebook 3.R.E.Horton and J.E.McCarty,Damage 2009,Gardner Publications Inc Tolerance of Composites,Engineered Ma- S.K.Mazumdar,Composites Manufacturing: terials Handbook,Vol 1,Composites,ASM Materials.Product.and Process Engineer- International.1987 ing,CRC Press,2002
Chapter 1: Introduction to Composite Materials / 29 2. M.C.Y. Niu, Composite Airframe Structures, 2nd ed., Hong Kong Conmilit Press Limited, 2000 3. R.E. Horton and J.E. McCarty, Damage Tolerance of Composites, Engineered Materials Handbook, Vol 1, Composites, ASM International, 1987 Fig. 1.35 Composites are not always the best choice. This avionics rack machined from an aluminum alloy block would not be cost-competitive if made of composites. Source: The Boeing Company Selected References • High-Performance Composites Sourcebook 2009, Gardner Publications Inc • S.K. Mazumdar, Composites Manufacturing: Materials, Product, and Process Engineering, CRC Press, 2002