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Ch 1Ch 1 -- IntroductionIntroduction

1.1-Introduction;1.2-Design, materials and manufacturing;1.3-Properties of engineering materials;

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1.5-Some trends and difficulties.

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Why should an engineer ... study materials?

1.1-Introduction.

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Design problem involving materials...selecting the right materials...manufacturing processes

Suitability to fit the design and shape Properties...(Ex. Strength and ductility)

Processing techniques

1.2-Design, materials and manufacturing.

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high temperature / corrosive environments] Aesthetic properties

Environmental and social factors Economics... ...

The more familiar an engineer with the various characteristics and structure-properties

relationship, and processing techniques; the more proficient and confident she/he to make

good choices based on the selection criteria's.

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Based on chemical make up and atomic structure materials can be classified into:

Metals: iron; aluminium; copper; gold...etc.(C,O...non metallic elements)


1.3-Properties of engineering materials.

Polymers: plastic and rubber ( organic compounds...C,H).

Extremely ductile and pliable (easily formed into complex shapes)

Ceramics and Glasses: porcelain; glass; cement.

Relatively stiff and strong, hard, ceramics are extremely brittle

(lack ductility)

Composites: composed of two or more individual materials (naturally and man made)Bone, Wood, Fibreglass, Carbon Fibre (CFRP). 4


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Materials utilized in high-tech applications...called advanced materials

It is traditional materials whose properties have been enhanced

Semiconductors: Intermediate electrical properties.

Biomaterials: Component implanted in human body.


Nano-engineered materials: Grain size 100 nanometers (500 atoms diameter).Example carbon nano-tubes.

Smart materials (intelligent materials): Have the ability to sense changes in their

environments and respond to these changes. Example shape memory alloy and

MIMS (microelectromechanicaldevices)

Nano-engineered materials and Smart materials ...Materials of the future

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Properties of materials (categories):

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Metals: Electrical conductors.Ceramics: Electrical resistive (Insulating materials).Polymers: Electrical resistive (Insulating materials).

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1.4-Cost and availability.

Choice of materials for particular application (engineering structure) can be

influenced by another factors such as...cost...availability?

Examples?

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1.5-some trends and difficulties.

Design; Properties; Manufacturing techniques; Cost; Availability;......

Mineral/material resources are not renewable (finite)...Copper, lead and silver...resources could be exhausted in our lifetime...

Energy consumed in production and processing some metals becomes anssue...

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End of Ch 1End of Ch 1

NextNext

Ch 2Ch 2 Atomic structure and bondingAtomic structure and bonding

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