7/31/2019 Production technology Ch09

1/12

Kalpakjian SchmidManufacturing Engineering and Technology 2001 Prentice-Hall Page 7-1

CHAPTER 9

Composite Materials: Structure, GeneralProperties, and Applications

7/31/2019 Production technology Ch09

2/12

Kalpakjian SchmidManufacturing Engineering and Technology 2001 Prentice-Hall Page 7-2

Application of Advanced Composite Materials

Figure 9.1Application ofadvancedcompositematerials in

Boeing 757-200commercialaircraft. Source:BoeingCommercialAirplaneCompany.

7/31/2019 Production technology Ch09

3/12

Kalpakjian SchmidManufacturing Engineering and Technology 2001 Prentice-Hall Page 7-3

Methods of Reinforcing Plastics

Figure 9.2 Schematicillustration of methodsof reinforcing plastics

(matrix) with (a)particles, and (b) shortor long fibers orflakes. The four layersof continuous fibers inillustration (c) areassembled into a

laminate structure.

7/31/2019 Production technology Ch09

4/12

Kalpakjian SchmidManufacturing Engineering and Technology 2001 Prentice-Hall Page 7-4

Types and General Characteristics ofComposite Materials

TABLE 9.1

Material Characteristics

Fibers

Glass High strength, low stiffness, high density; lowest cost; E (calcium aluminoborosilicate) and S(magnesia-aluminosilicate) types commonly used.

Graphite Available as high-modulus or high-strength; low cost; less dense than glass.

Boron High strength and stiffness; highest density; highest cost; has tungsten filament at its center.Aramids (Kevlar) Highest strength-to-weight ratio of all fibers; high cost.

Other fibers Nylon, silicon carbide, silicon nitride, aluminum oxide, boron carbide, boron nitride, tantalum

carbide, steel, tungsten, molybdenum.

Matrix materialsThermosets Epoxy and polyester, with the former most commonly used; others are phenolics,

fluorocarbons, polyethersulfone, silicon, and polyimides.Thermoplastics Polyetheretherketone; tougher than thermosets but lower resistance to temperature.

Metals Aluminum, aluminum-lithium, magnesium, and titanium; fibers are graphite, aluminum oxide,

silicon carbide, and boron.

Ceramics Silicon carbide, silicon nitride, aluminum oxide, and mullite; fibers are various ceramics.

7/31/2019 Production technology Ch09

5/12

Kalpakjian SchmidManufacturing Engineering and Technology 2001 Prentice-Hall Page 7-5

Strength and Stiffness of Reinforced Plastics

Figure 9.3 Specific tensile strength (tensile strength-to-density ratio) and specific tensile modulus(modulus of elasticity-to-density ratio) for various fibers used in reinforced plastics. Note the widerange of specific strengths and stiffnesses available.

7/31/2019 Production technology Ch09

6/12

Kalpakjian SchmidManufacturing Engineering and Technology 2001 Prentice-Hall Page 7-6

Typical Properties of Reinforcing Fibers

TABLE 9.2

Type

Tensile

strength

(MPa)

Elastic

modulus

(GPa)

Density

( kg/m3) Relative cost

Boron 3500 380 2600 Highest

Carbon

High strength 3000 275 1900 Low

High modulus 2000 415 1900 Low

GlassE type 3500 73 2480 Lowest

S type 4600 85 2540 Lowest

Kevlar

29 2800 62 1440 High

49 2800 117 1440 High

Note: These properties vary significantly depending on the material and method of preparation.

7/31/2019 Production technology Ch09

7/12

Kalpakjian SchmidManufacturing Engineering and Technology 2001 Prentice-Hall Page 7-7

Fiber Reinforcing

Figure 9.4 (a) Cross-section of a tennis racket, showing graphite and aramid (Kevlar) reinforcing fibers. Source:J. Dvorak, Mercury Marine Corporation, and F. Garrett, Wilson Sporting Goods Co. (b) Cross-section of boron

fiber-reinforced composite material.

7/31/2019 Production technology Ch09

8/12

Kalpakjian SchmidManufacturing Engineering and Technology 2001 Prentice-Hall Page 7-8

Effect of Fiber Type on Fiber-Reinforced Nylon

Figure 9.5 The effectof type of fiber onvarious properties offiber-reinforced nylon(6,6). Source: NASA.

7/31/2019 Production technology Ch09

9/12

Kalpakjian SchmidManufacturing Engineering and Technology 2001 Prentice-Hall Page 7-9

Fracture Surfaces of Fiber-Reinforced EpoxyComposites

(a) (b)

Figure 9.6 (a) Fracture surface of glass-fiber reinforced epoxy composite. The fibers are10 m (400 in.) in diameter and have random orientation. (b) Fracture surface of agraphite-fiber reinforced epoxy composite. The fibers, 9 m-11 m in diameter, are inbundles and are all aligned in the same direction. Source: L. J. Broutman.

7/31/2019 Production technology Ch09

10/12

Kalpakjian SchmidManufacturing Engineering and Technology 2001 Prentice-Hall Page 7-10

Tensile Strength of Glass-Reinforced Polyester

Figure 9.7 The tensile strengthof glass-reinforced polyester as afunction of fiber content andfiber direction in the matrix.Source: R. M. Ogorkiewicz, TheEngineering Properties ofPlastics. Oxford: Oxford

University Press, 1977.

7/31/2019 Production technology Ch09

11/12

Kalpakjian SchmidManufacturing Engineering and Technology 2001 Prentice-Hall Page 7-11

Example of Advanced Materials Construction

Figure 9.8 Cross-section of acomposite sailboard, an exampleof advanced materialsconstruction. Source: K.Easterling, Tomorrows Materials

(2d ed.), p. 133. Institute ofMetals, 1990.

7/31/2019 Production technology Ch09

12/12

Kalpakjian SchmidManufacturing Engineering and Technology 2001 Prentice-Hall Page 7-12

Metal-Matrix Composite Materials andApplications

TABLE 9.3

Fiber Matrix Applications

Graphite Aluminum

Magnesium

Lead

Copper

Satellite, missile, and helicopter structures

Space and satellite structures

Storage-battery plates

Electrical contacts and bearings

Boron AluminumMagnesium

Titanium

Compressor blades and structural supportsAntenna structures

Jet-engine fan blades

Alumina AluminumLead

Magnesium

Superconductor restraints in fission power reactorsStorage-battery plates

Helicopter transmission structures

Silicon carbide Aluminum, titanium

Superalloy (cobalt-base)

High-temperature structures

High-temperature engine components

Molybdenum, tungsten Superalloy High-temperature engine components