Introduction to Materials
Science and Engineering
Learning Objectives :
Upon completion of this chapter, the student
should be able to:
• List six different property classifications of
materials that determine their applicability.
• Cite the four components that are involved in the
design, production, and utilization of materials.
• Cite three criteria that are important in the
selection process.
Materials Science and Engineering
Materials Science – investigating relationships
that exist between the structure and properties of
materials.
Materials Engineering – is, on the basis of these
structure-property correlations, designing or
engineering the structure of a material to produce
a pre-determined set of properties
Materials in day to day life
Materials: The Milestones of Progress
• Development and advancement of Human societiesclosely related with materials
• Civilizations have been named based on the level of their
materials development – Stone age, Bronze age etc.
Quest for newer materials:
The driving force for the progress- stone age to modern
age
Quest for more advanced materials
needs as the civilization progressed.
to meet the growing
Stone age
Stone age – People living in caves and hunting
with stone-made weapons
200,000 BC
Discovery of fire – Said to be the most significant
discovery in human civilization. However, till the time
the fire was controlled to contain and utilize the heat,
it was not significant.
Containing the fire – Was not possible without
materials. Started with clay (a ceramic material) pots
and now we have all kinds of means to control and
contain fire.
Introduction of metals
First metals to be discovered – Copper and Gold
Material processing - Annealing and Shaping. Throwing
copper into camp fire and hammering in early days
Melting and casting of metals. Melting of Gold to give it
different shapes
Reduction of copper from its ore – Nile Valley The
dawn of metallurgy.
Perhaps discovered by chance much before by early
potters
Discovery of Alloy - Metal Combinations
The discovery of alloy – combination of
metals
Mixing of Tin with Copper – Bronze
Copper ore invariably contains some Tin – Mixing of
different ores having different Tin content produced
the first Bronzes.
Iron and Steel – Building blocks of human civilization
Iron wheels – discovery of iron making.
Revolution in warfare and cultivation
Invention of Blast furnace – Production of pig iron
from ores
Sir Henry Bessemer (1813-1898) Bessemer
steel making patent
20th Century
Many other steel making processes
Early 20th Century – The golden era
1890 - 1910 AD
Hall process- Electrochemical process for
extraction of Aluminium from Alumina
(Al2O3)
Revolution in Transportation –
Discovery of automobiles and Aero
plane
Process for making Nylon –
Introduction of plastics
The Electronic Revolution
Zone refining – A
metallurgical process to
produce ultra pure Si
Ultra pure Si through zone refining – Si
chip, the heart of electronics. Smaller and
smaller Si wafers - Miniaturization
Superconductors
High temperature ceramic MRI Machine, Brain Scan –
superconductors
Advancement in Medical
science
Magnetic Levitation: Maglevtrain
:– 300 – 500 kmph
Why do we need to study Materials Science and
Engineering?
Processing/Structure/Properties/Performance
Correlations
• Structure of a material usually relates to the
arrangement of its internal components which
can be further classified into four categories
described in the next section.
• A property is a material trait in terms of the kind
and magnitude of response to a specific imposed
stimulus.
Structure
•Macroscopic – viewable with the un-aided eye
•Microscopic – groups of atoms that are
normally agglomerated together
•Atomic – organization of atoms or molecules
•Sub atomic – electrons and nuclei (protons
and neutrons)
In addition to structure and properties,
two other important components are involved
in the science and engineering of materials –
namely, processing and performance. With
regard to the relationships of these four
components, the structure of a material will
depend on how it is processed. Furthermore,
a materials performance will be a function of
its properties.
Processing
Structure
Properties
Performance
Classification of Materials
1.) Metals
Materials in this group are composed of one
or more metallic elements and often also
nonmetallic elements. Atoms in metals and their
alloys are arranged in a very orderly manner, and
in comparison to the ceramics and polymers, are
relatively dense.
2.) Ceramics
Ceramics are compounds between metallic
and nonmetallic elements; they are most
frequently oxides, nitrides and carbides. For
example, common ceramic materials include
aluminum oxide, silicone dioxide, silicon carbide,
etc. Ceramic materials are more resistant to high
temperatures and harsh environments than
metals and polymers.
3.) Polymers
Polymers include the familiar plastic and
rubber materials. Many of them are organic
compounds that are chemically based on carbon,
hydrogen and other nonmetallic elements. These
materials typically have low densities, whereas
their mechanical characteristics are generally
dissimilar to the metallic and ceramic materials –
they are not as stiff nor as strong as these other
material types.
4.) Composites
A composite is composed of two or more
materials, which come from metals, ceramics and
polymers. The design goal of a composite is to
achieve a combination of properties that is not
displayed by any single material, and also to
incorporate the best characteristics of each of the
component materials.
5.) Advanced Materials
Materials that are utilized in high-technology
applications are termed as advanced materials.
These materials are typically traditional materials
whose properties have been enhanced, and also
newly developed, high-performance materials.
These type of materials is further classified into
four kinds, namely, semiconductors, biomaterials,
smart materials and nanomaterials.
a.) Semiconductors
Have electrical properties that are
intermediate between the electrical conductors
(metals and alloys) and insulators (ceramics and
polymers)
b.) Biomaterials
Biomaterials are employed in components
implanted into the human body to replace
diseased or damaged body parts.
c.) Smart Materials
The adjective “smart” implies that these
materials are able to sense changes in their
environment and then respond to these changes
in predetermined manners.
d.) Nanomaterials
Nanomaterials may be one of the four basic
materials, however, unlike those other materials,
they are not distinguished on the basis of their
chemistry, but rather, size.
Summary:
• One aspect of materials science is the
investigation of relationships that exist between
the structures and properties of materials. By
structure we mean how some internal
component(s) of the materials is (are) arranged.
In terms of (and with increasing) dimensionality,
structural elements include subatomic, atomic
microscopic, and macroscopic.
• On the basis of chemistry and atomic structure,
materials are classified into three general
categories: metals (metallic elements), ceramics
(compounds between metallic and nonmetallic
elements), and polymers (compounds composed
of carbon, hydrogen, and other nonmetallic
elements.) In addition, composites are composed
of at least two different material types.
• Another materials category is the advanced materials
that are used in high-tech applications. These include
semiconductors (having electrical conductivities
intermediate between conductors and insulators),
biomaterials (which must be compatible with body
tissues), smart materials (those that sense and
respond to changes in their environments in
predetermined manners), and nanomaterials (those
that have structural features on the order of a
nanometer, some of which may be designed on the
atomic/molecular level)
Good, better, best. Never let it rest. Until your good is better and your better is best.
- St. Jerome
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