Callister - An introduction - 8th edition

Chapter 22 Economic, Environmental, and
Societal Issues in Materials
Science and Engineering
(a) Photograph showing beverage cans that are made
of an aluminum alloy (left) and a steel alloy (right). The
steel beverage can has corroded significantly, and, therefore,
is biodegradable and nonrecyclable. Conversely, the
aluminum can is nonbiodegradable and recyclable
inasmuch as it experienced very little corrosion.
(b) Photographs showing a fork made of the biodegradable
polymer poly(lactic acid) at various stages of
degradation. As may be noted, the total degradation
process took about 45 days. [Figure (b) courtesy of
Roger Ressmeyer/© Corbis; Figure (c) courtesy of Jennifer
Welter.]
(a)
(b)
(c)
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