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Material Science - Coggle Diagram
Material Science
Type of Materials
Metals & Alloys
• Pure metals include: Iron, aluminium,
zinc, copper, magnesium, titanium,
nickel etc
• Alloys: combination of two or more
metals – steel, cast iron, brass – to
provide improvement in particular
property of permit better combination
of properties.
ceramics
Raw materials consist of metals and nonmetals
compound (C, N, O, P, S)
• Eg: Bricks, glasses, tableware, refractory
(material with high melting point thermal
shock resistance) and abrasives
• E.g. Al (metal) but Al2 O3 (ceramic) – different
properties
polymers
• Produced by creating large molecular structures from
organic molecules (polymerization)
Examples: rubber, plastics and
adhesives
• Two types
Thermoplastic - long molecular chains are not rigidly
connected
Thermosetting- molecular chains are tightly linked
semiconductors
• Conductivity between metals (106 ohm-1 m-1 )
and insulators ((10-10 – 10-20 ohm-1 m-1)
can be controlled (doping)
• Application– essential for electronics devices
(diodes, transistors, ICs)
• Examples:
Elementals Si, Ge,
Compounds : GaAs, InP
• Brittle
composites
• Formed from two or more materials producing
properties that cannot be obtained by any single
material
• Examples: concrete, plywood and fiberglass
(glass fibers embedded in a polymer matrix)
• Can produce lightweight, strong, ductile, high
temperature-resistant
• Essential in advanced aircraft and aerospace –
carbon-fiber-reinforced polymers
Structure of Materials
Electronic Structures
A system that is comprised of many parts
The manner in which the different parts of the material/system are put together
The parts of the system that are distinguishable through composition, size, shape, etc.
The physical disposition of the parts of the system
Atomic Arrangement
Regular atomic arrangement : metals, semiconductors, many ceramics,
some polymers
• No orderly arrangement : ceramics, polymers amorphous
(glassy) -> behave differently from crystalline materials
• Influences mechanical properties
(microstructure) – Grain
structurefound in most metals, semiconductors, ceramics and occasionally in
polymers
• size and shape of the grains play a key role in determining
mechanical property
material with a specific grain size and shape or one grain
(single crystal) shows certain property
e.g. silicon chips for IC, metals for jet engine parts
(macrostructure) – Phase structure
each phase has its unique atomic arrangement and properties
• control of the type, size, distribution, and amount of these
phases can control properties of material
• phases can be determined using x-ray diffraction
General Properties of Materials
Mechanical Properties
Describe how a material responds to an
applied force
Determine the ease with which a material can
be deformed into a useful shape
– forging, drilling and forming
a. Strength (modulus of elasticity)
• tensile strength
• yield stress
b. Ductility (modulus of elasticity)
• % elongation
• % reduction in area
c. Stiffness (modulus of elasticity)
• resistance to bending
d. Fatigue
• continating force
• endurance limit
• fatigue life
Physical Properties
a. Density
b. Electrical properties
• response towards electrical field
• conductivity
• dielectric constant
• dielectric strength
• Ferroelectricity
• piezoelectricity
Chemical Property
Related to chemical changing of chemica rl eidaectniotinty and
• Electronegativity
• Ionization potential
• pH balance
