Materials Science and Engineering for the 1990s Maintaining Competitiveness in the Age of Materials (1989) / Chapter Skim
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1. What is Materials Science and Engineering
1. What is Materials Science and Engineering
Pages 19-34
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From page 19... ...
Only in the last 25 years, and especially in the last decade, has the intellectual foundation of the field that we call materials science and engineering begun to take shape and to achieve recognition. This has occurred just as the field itself is expanding greatly and contributing significantly to society.
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From page 20... ...
This efficiency depends directly on the temperature at which the device can operate well; thus materials that are strong at high temperatures are desired. Superalloys can now operate at temperatures of over 2000°F, and advanced ceramics may push engine operating temperatures to 2500°F (Figure 1.2~.
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From page 21... ...
Today, permanent magnets have magnetic strengths more than 100 times greater than those available at the turn of the century (Figure 1.3~. These and other magnetic materials are making possible smaller, more powerful motors and better and smaller sound systems, and they are carrying out many other hidden tasks in modern machines and devices.
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From page 22... ...
22 MATERIALS SCIENCE AND ENGINEERING FOR THE 1990s 45 40 35 30 a, 28 o ~ 24 I m 20 16 12 8 4 FIGURE 1.3 Progress in the flux-magnetization product (a measure of the strength of a permanent magnet in megagauss oersteds) of magnetic materials over time.
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From page 23... ...
The technical difficulties that prevent the general use of these materials today are precisely those connected with synthesis and processing that contribute the principal challenge to materials science and engineering as a whole. · Scientists and technicians improved the transparency of silica glass slowly over the centuries from 3000 B.C.
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From page 24... ...
This achievement is a triumph for both materials scientists and materials engineers, who have mastered the complex interacting relationships between phenomena, materials, and processing. · Innovations in materials processing have had enormous impacts on the factory floor.
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From page 25... ...
32:64-71.) Materials science and engineering influences our lives each time we buy or use a new device, machine, or structure.
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From page 26... ...
26 ,-1 '\ ~ G E | ~ ~ l ~ ~\< o Ci' o o~ , ~ m CO CD C' =0 O ~ cn O O ~ m · O 1 71 1 , , CO 0 0 U
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From page 27... ...
MATERIALS SCIENCE AND ENGINEERING AS A FIELD What is the nature of materials science and engineering, a field that so profoundly affects the quality of our lives in so many different ways? The intellectual core and definition of the field stem from a realization concerning the application of all materials: whenever a material is being created, developed, or produced, the properties or phenomena the material exhibits are of central concern.
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From page 28... ...
The field of materials science and engineering has evolved along many parallel and intertwined paths associated with academic disciplines, R&D laboratories, and the factory floor. It draws on areas as diverse as quantum mechanics on the one hand and societal needs, including manufacturing, on the other.
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From page 29... ...
Condensed-matter physicists, solid-state chemists, and synthetic chemists form the bridge between fundamental science and a subset of that science on which modern materials science and engineering rests. These sciences aim to increase knowledge, and especially understanding, of structure, phenomena, behavior, or synthesis.
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From page 30... ...
By the early 1970s, a painstaking materials science effort lasting more than 60 years had led to metallic compounds that remained superconducting at up to 23 K, an average increase of about 0.3 K/yr. No further progress occurred until 1986, when researchers studying entirely different classes of compounds discovered superconductivity at up to 39 K
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From page 31... ...
(a) Semiconductor devices in which the quantum Hall effect is observed hold current-carrying electrons within a thin layer of semiconducting crystal.
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From page 32... ...
Similarly, building and processing of modern composite materials require an understanding of surface science and molecular bonding as well as a strong engineering foundation. Future development of superconducting materials is also essentially dependent on materials science and engineering because such advances require expertise in understanding materials phenomena and their relationship to structure and defects in the structure, to processing (which influences the structure)
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From page 33... ...
Even though an individual may identify with a physics, metallurgy, or other department in a university emphasizing a particular aspect of the field, it is implicitly and increasingly recognized that important contributions will come from various disciplines working together. The interdisciplinary nature of materials science and engineering and its growth as a field have also been recognized in the professional world outside academia.
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From page 34... ...
Opportunities for research are discussed from two perspectives: Chapter 3 describes needs for new materials and for novel methods of processing in terms of the functional roles of materials; Chapter 4 describes research opportunities in the context of the four basic elements of materials science and engineering, thus emphasizing the intellectual coherence of the field while also stressing the essential connection between basic research and progress in developing materials. Educational challenges posed by the national need to encourage such progress and to ensure an adequate supply of well-trained materials researchers are considered in Chapter 5, which briefly assesses resources available for educating materials scientists and engineers at various levels of the U.S.
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