• ceramic • metallic • polymeric • composite
covalent
ionic
metallic
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Inorganic and Non-metallic Materials Wide term: ceramics Including: glass, cement &concrete, pottery &
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4. Material Science and Engineering Materials science & engineering (MSE): • inventing new materials • investigation of a material’s structure • improving materials by developing a deeper understanding of microstructure ~ composition ~ processing relationships.
• Physical properties: electrical, magnetic, optical, thermal
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Structure • On an atomic level, structure encompasses
the organization of atoms or molecules relative to one another. Processing • synthesis: how materials are made from naturally occurring or man-made chemicals. • processing: how materials are shaped into useful components
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3. Properties mechanical properties determine : ➢ how well the material performs in service ➢ the ease with which the material can be formed into a useful shape
Inorganic & Non-metallic, Metallic Polymers, Composites 1.3 Substances, Resources and Materials 1.4 Structure ~ Properties ~ Processing 1.5 Material Science and Engineering 1.6 Latest Development & Tendency
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1. Definition Materials: • consist of discrete discrete particles • having a submicroscopic size • their behavior is determined by atomic theories Materials are defined as:
porcelain, refractory Consisting of: metallic & nonmetallic elements Structure: crystalline or noncrystalline Properties: • high hardness • high-temperature strength • brittle • good heat and wear resistance
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Metallic Materials Properties: • good thermal and electrical conducting • not transparent to visible light • a lustrous appearance • quite strong • ductile
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Polymers consist of organic (carbon-containing) long molecular chains or networks.
Properties:
• electrical insulators
• low density
• extremely flexible
solids used by man to produce items which constitute the support for his living environment.
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2. Types of materials: based on the structure, the nature of the atomic bond
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The four basic aspects of materials science and technology
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Questions：
1. What are the differences in chemical bonding between ceramics and polymers? And what are the differences in properties between these two materials?
Structure: crystalline structure the atoms are arranged in an orderly manner.
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Types of metals: • ferrous metals: steels and cast irons • nonferrous metals: do not contain iron aluminum, copper, zinc, titanium, nickel
2. What is the same feature in microstructures for ceramics and metals? Please explain this.
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• low softening temperC, H, nonmetallic elements
Types: plastics, rubber, fiber
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Composites Consisting:
a selected filler or reinforcing material and a compatible resin binder composites do not dissolve in each other, and they can be physically identified by an interface between them.
Introduction to Materials
材料概论
September 2017
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Chapter 1 Introduction to Materials
1.1 A Brief History of Materials 1.2 Definition & Classification of Materials