Page 255 - 04. Subyek Engineering Materials - Manufacturing, Engineering and Technology SI 6th Edition - Serope Kalpakjian, Stephen Schmid (2009)

234 Chapter 9 Composite Materials: Structure, General Properties, and Applications

9.5l. Design and describe a test method to determine the the following: (a) very low temperatures, (b) very high tem-
mechanical properties of reinforced plastics in their thickness peratures, (c) vibrations, and (d) high humidity.
direction. (Note, for example, that plywood is not particularly 9.56. Obtain a textbook on composite materials and inves-
strong in its thickness diection.) tigate the effective stiffness of a continuous fiber-reinforced
9.52. As described in this chapter, reinforced plastics can be polymer. Plot the stiffness of such a composite as a function
adversely affected by the environment-in particular, moisture, of orientation with respect to the fiber direction.
chemicals, and temperature variations. Design and describe test 9.57. Derive a general expression for the coefficient of ther-
methods to determine the mechanical properties of composite mal expansion for a continuous fiber-reinforced composite in
materials subjected to these environmental conditions. the fiber direction.
9.53. Comment on your observations on the design of the 9.58. It is possible to make fibers or whiskers with a varying
sailboard illustrated in Fig. 9.8. cross section, or a “wavy” fiber. What advantages would
9.54. Make a survey of various sports equipment and iden- such fibers have?
tify the components made of composite materials. Explain 9.59. Describe how you can produce some simple compos-
the reasons for and the advantages of using composites in ite materials using raw materials available around your
these specific applications. home. Explain.
9.55. Several material combinations and structures were 9.60. Gel spinning is a specialized process used in making
described in this chapter. In relative terms, identify those fibers with high strength or special properties. Search the
that would be suitable for applications involving one of technical literature and write a brief paper on this subject.