C hapter 4 Material Classes, structure, and properties
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Examples of ceramic materials are glasses, bricks, stones, and porcelain. Because of their ionic and covalent types of bonds, ceramic
materials are hard, brittle, and good insulators. In addition, they
have very good corrosion resistance properties.
polymeric Materials
Polymeric materials consist of long molecules composed of many
organic molecule units, called mer (therefore the term polymer).
Polymers are typically divided into natural polymers such as wood,
rubber, and wool; biopolymers such as proteins, enzymes, and cellulose; and synthetic polymers such as Teflon and Kevlar. Among
the synthetic polymers there are elastomers, which exhibit large
elongations and low strength, and plastics, which exhibit large variations in properties. Polymeric materials are in general good insulators and have good corrosion resistance.
Composite Materials
Composite materials are formed of two or more materials with very
distinctive properties, which act synergistically to create properties
that cannot be achieved by each single material alone. Typically,
one of the materials of the composite acts as a matrix, whereas the
other materials act as reinforcing phases. Composite materials can
be classified as metal-matrix, ceramic-matrix, or polymer-matrix.
For each of these composite materials, the reinforcing phases can
be a metal, a ceramic, or a polymer, depending on the targeted
applications.
electronic Materials
The electronic class of materials is a bit broader than the previous
classes because electronic materials can encompass metals, ceramics, and polymers, such as the metal copper that is used as interconnects in most electronic chips, the ceramic silica that is used
as optical fibers, and the polymer polyamides, which are used as a
dielectric. However,the term electronic material is used to describe
materials that exhibit semiconductor properties. The most important of these materials is silicon, which is used in practically all
electronic components. Other materials such as germanium and
gallium arsenide are also part of this class.
Biomaterials
The biomaterials class is related to any material, natural or synthetic, that is designed to mimic, augment, or replace a biological
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Examples of ceramic materials are glasses, bricks, stones, and porcelain. Because of their ionic and covalent types of bonds, ceramic
materials are hard, brittle, and good insulators. In addition, they
have very good corrosion resistance properties.
polymeric Materials
Polymeric materials consist of long molecules composed of many
organic molecule units, called mer (therefore the term polymer).
Polymers are typically divided into natural polymers such as wood,
rubber, and wool; biopolymers such as proteins, enzymes, and cellulose; and synthetic polymers such as Teflon and Kevlar. Among
the synthetic polymers there are elastomers, which exhibit large
elongations and low strength, and plastics, which exhibit large variations in properties. Polymeric materials are in general good insulators and have good corrosion resistance.
Composite Materials
Composite materials are formed of two or more materials with very
distinctive properties, which act synergistically to create properties
that cannot be achieved by each single material alone. Typically,
one of the materials of the composite acts as a matrix, whereas the
other materials act as reinforcing phases. Composite materials can
be classified as metal-matrix, ceramic-matrix, or polymer-matrix.
For each of these composite materials, the reinforcing phases can
be a metal, a ceramic, or a polymer, depending on the targeted
applications.
electronic Materials
The electronic class of materials is a bit broader than the previous
classes because electronic materials can encompass metals, ceramics, and polymers, such as the metal copper that is used as interconnects in most electronic chips, the ceramic silica that is used
as optical fibers, and the polymer polyamides, which are used as a
dielectric. However,the term electronic material is used to describe
materials that exhibit semiconductor properties. The most important of these materials is silicon, which is used in practically all
electronic components. Other materials such as germanium and
gallium arsenide are also part of this class.
Biomaterials
The biomaterials class is related to any material, natural or synthetic, that is designed to mimic, augment, or replace a biological