dlsu scimatp

SCIMATP May 31, 2012

Reminder

• Join our yahoogroup

Individual Project

Scrapbook

Include the following:

1. Original Paper, signed

2. Improved Drawing of your 2062 gadget

3. Identify the important parts/components of the

gadget

4. Identify the material that you think should make

up each part

5. Include a discussion of the important properties

of each material that makes it suitable for the

gadget

Classification of Materials

Classification of Materials

• classification of materials is usually based on the

atomic bonding forces of the materials.

• General Classification

– Metals

– Ceramics

– Polymers

– Composites

– Semiconductors

ACTIVITY

• Identify whether the material given to you is a

metal, ceramic, polymer, composite, or

semiconductor

– You may ask anyone in your group to help you

• Paste your material name under the correct

heading on the manila paper pasted on the board

http://farm1.static.flickr.com/197/457746430_9d0172dcda_o.jpg

METALS

Ring: 75% copper, 25% nickel

Center: 92% copper, 6% aluminum, 2% nickel

METALS

• They have large numbers of non-localized/free

electrons.

• General Properties:

1. shiny luster

2. grayish-silver color (except gold and copper)

3. hardness (except sodium and calcium)

4. good heat and electrical conductivity

5. high melting and boiling points (except mercury)

6. malleability (can be hammered into a sheet)

7. ductility (can be pulled into a wire)

METALS

• Examples:

• Ferrous metals and alloys

(irons, carbon steels, alloy

steels, stainless steels,

tool and die steels)

• Nonferrous metals and

alloys (aluminum, copper,

magnesium, nickel,

titanium, precious metals,

refractory metals,

superalloys)

• Applications:

• coinage, jewelry,

automobiles, structural

components for

buildings, hulls of large

ships, etc.

Credit: http://www.ndt-ed.org

http://www.turkuceramics.fi/kuvat/turku-ceramics_en.jpg

CERAMICS

CERAMICS

• Ceramics are compounds between metallic and

nonmetallic elements.

• They are most frequently oxides, nitrides, and carbides

and are composed of clay minerals, cement, and glass.

• General Properties:

1. typically insulative to the passage of heat and

electricity

2. more resistant to high temperatures and harsh

environments

3. hard but very brittle

CERAMICS

• Applications:

• insulators, magnets, aerospace, biomedical,

construction, nuclear industries

• Examples

• Glasses

• Glass ceramics

• Graphite


POLYMERS

• Many of them are organic compounds that

are chemically based on carbon, hydrogen,

and other nonmetallic elements.

• They have very large molecular structures.

• Properties:

1. low density

2. may be extremely flexible

3. Good electrical resistivity

POLYMERS

• Applications:

• plastic bags, electrical and thermal insulation,

toys, pipes, flooring, clothing, paints, adhesive

• Examples:

• Thermoplastics plastics

• Thermoset plastics

• Elastomers


SEMICONDUCTORS

• have electrical properties that are

intermediate between the electrical

conductors and insulators

• the electrical characteristics are extremely

sensitive to the presence of minute

concentrations of impurity atoms

• Applications:

• integrated circuits

• Electronics

• computers Credit: http://www.ovenind.com

COMPOSITES

• Composite materials are engineered materials

that consist of more than one material type.

• They are designed to display a combination of

the best characteristics of each of the

component materials

COMPOSITES

• Applications:

• space shuttles, construction of pavement,

roads, parking lots, armor

• Example:

• Fiberglass – glass fibers are

embedded within a polymeric

material

- acquires strength

from the glass and flexibility

from the polymer

Density

Stiffness

Strength

Resistance to fracture

Electrical Conductivity

Seatwork

ELEMENT

ASSIGNMENT

• Download Atoms, Bonding and Structure v2.0

• Explore and learn

References

• Callister, William Jr. (2005) Materials Science and Engineering:

An Introduction (7th Ed.), John Wiley and Sons, Inc.

• Askeland, Donald R. and Phule, Pradeep P., (2006) The

Science and Engineering of Materials , Thomson

• Natividad, Michelle (2006) Classification of Materials. A ppt

presentation

• Powerpoint Background: http://martz90.deviantart.com/art/Blue-and-Green-

Wallpaper-210690826

For SCIMATP class Term 3, A.Y. 2011-2012

dlsu scimatp

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