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ENGI 7007: Ocean Engineering Materials

Lecture 1: Chapter 1

Dr. Amy Hsiao Spring 2013

Chapter 1

Materials for Engineering

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Retrieved as Google image: http://www.ibiblio.org/jimmy/folkden-wp/?p=7408, April 30, 2012

Introduction: Marine Materials Concepts

Metallurgical analysis

Chemical analysis

Contemporary 1020 steel (low-carbon steel, 0.20 wt% carbon)

Mechanical behavior

Yield strength

Elongation at failure

Grain size

Ductile-to-brittle transition temperature

Charpy Impact tests

Mn:S content (alloying)

Impact energy

Longitudinal and transverse directions

Iron rivets

Temperature

Materials selection

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Materials Science &

Engineering

Performance

Properties

Process

Structure

Materials Science Paradigm

Example: Beverage Bottles

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Structure Properties Relationship

Structure Properties Relationship

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Figure 1.1 The evolution of engineering materials with time. Note the highly nonlinear scale. (From M. F. Ashby, Materials Selection in Mechanical Design, 2nd ed., Butterworth-Heinemann, Oxford, 1999.)

Everyday Materials

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The Periodic Table

Figure 1.4 Periodic table of the elements. Those elements that are inherently metallic in nature are shown in color.

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Figure 1.2 The Golden Gate Bridge north of San Francisco, California, is one of the most famous and most beautiful examples of a steel bridge. (Courtesy of Dr. Michael Meier.)

Amy Hsiao

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Rosie the Riveter in front of the USS Pampanito (USS-383)

Figure 1.7 Periodic table with ceramic compounds indicated by a combination of one or more metallic elements (in light color) with one or more nonmetallic elements (in dark color). Note that elements silicon (Si) and germanium (Ge) are included with the metals in this figure but were not included in the periodic table shown in Figure 1.4. They are included here because, in elemental

form, Si and Ge behave as semiconductors (Figure 1.16). Elemental tin (Sn) can be either a metal or a semiconductor, depending on its crystalline structure.

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Figure 1.5 Some common ceramics for traditional engineering applications. These miscellaneous parts with characteristic resistance to damage by high temperatures and corrosive environments are used in a variety of furnaces and chemical processing

systems. (Courtesy of Duramic Products, Inc.)

Figure 1.6 High-temperature sodium vapor lamp made possible by use of a translucent Al2O3 cylinder for containing the sodium vapor. (Note that the Al2O3 cylinder is inside the exterior glass envelope.) (Courtesy of General Electric Company.)

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Figure 1.8 Some common silicate glasses for engineering applications. These materials combine the important qualities of transmitting clear visual images and resisting chemically aggressive environments. (Courtesy of Corning Glass Works.)

Figure 1.8 Schematic comparison of the atomic-scale structure of (a) a ceramic (crystalline) and (b) a glass (noncrystalline). The open circles represent a nonmetallic atom, and the solid black circles represent a metal atom.

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Figure 1.10 The small cable on the right contains 144 glass fibers and can carry more than three times as many telephone conversations as the traditional (and much larger) copper-wire cable on the left. (Courtesy of the San Francisco Examiner.)

Space Shuttle Discovery Thermal Protection Systems

(photo credit: Adriane Faust, April 2012)

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Figure 1.14 Example of a fiberglass composite composed of microscopic-scale reinforcing glass fibers in a polymer matrix. (Courtesy of Owens-Corning Fiberglas Corporation.)

Figure 1.15 Kevlar reinforcement is a popular application in modern high-performance tires. In this case, the durability of sidewall reinforcement is tested along concrete ridges at a proving ground track. (Courtesy of the Goodyear Tire and Rubber

Company.)

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Figure 1.12 Periodic table with the elements associated with commercial polymers in color.

Figure 1.11 Miscellaneous internal parts of a parking meter are made of an acetal polymer. Engineered polymers are typically inexpensive and are characterized by ease of formation and adequate structural properties. (Courtesy of the Du Pont Company,

Engineering Polymers Division.)

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Figure 1.13 Since its development during World War II, nylon fabric remains the most popular material of choice for parachute designs. (Courtesy of Stringer/Agence France Presse/Getty Images.)

Figure 1.16 Periodic table with the elemental semiconductors in dark color and those elements that form semiconducting compounds in light color. The semiconducting compounds are composed of pairs of elements from columns III and V (e.g., GaAs) or

from columns II and VI (e.g., CdS).

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Figure 1.17 (a) Typical microcircuit containing a complex array of semiconducting regions. (Photograph courtesy of Intel Corporation) (b) A microscopic cross section of a single circuit element in (a). The dark rectangular shape in the middle of the

micrograph is a metal component less than 50 nm wide. (Micrograph courtesy of Intel Corporation)

Figure 1.18 The modern integrated circuit fabrication laboratory represents the state of the art in materials processing. (Courtesy of the College of Engineering, University of California, Davis.)

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Ceramics

(Ionic & covalent bonding):

Metals

(Metallic bonding):

Polymers (Covalent & Secondary):

Large bond energy large Tm

large E

small a

Variable bond energy moderate Tm

moderate E

moderate a

Directional Properties Secondary bonding dominates

small Tm small E

large a

SUMMARY: PRIMARY BONDS

Tm is larger if Eo is larger.

PROPERTIES FROM BONDING: TM

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L F

Ao = E

Lo

Elastic modulus

E is larger if Eo is larger.

PROPERTIES FROM BONDING: E

Coefficient of thermal expansion, a

a is larger if Eo is smaller.

= a(T2-T1) L

Lo

coeff. thermal expansion

PROPERTIES FROM BONDING: a