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IV. Say if the following statements are true or false. Correct the false statements.

1. Copper was extracted by man more than 10,000 years ago.

2. Copper alloys appeared because there was shortage of pure copper.

3. Copper metals are important functional and decorative materials today.

4. In the 19th century the demand for copper greatly decreased.

5. The resources of copper will be worked out in the near future.

6. If Egyptian plumbing is recycled a lot of copper can be obtained.

V. Agree or disagree with these statements. Give reasons for your answer.

1. Copper metals possess valuable properties.

2. Technological progress increases the demand for copper.

3. There is no need to save copper resources.

4. Copper can and should be recycled.

VI. Complete the diagram that classifies the following engineering materials. The diagram should have three levels.

alloys

copper

brass

pure metals

metals

bronze

tin

VII. Give a title to the text.

Activity

I. a) Divide into groups and fill in the table using the information from the text and your background knowledge.

Copper Metals

Area of Application

Example

Necessary Properties

Medical Engineering

biostatic, corrosion-resistant

b) Compare your results. Which group has the longest list?

II. You have been invited to a conference on the advances in Materials Science. Prepare a report on the topic. "Present-day application of copper" and deliver it in class. Choose the most interesting one.

Writing

I. Study the table and write a paragraph about the appli­cations and properties of various copper alloys.

Name

Metals present

Uses

Aluminium bronze

Copper, aluminium

High tensile strength, can be cold-worked or cast, resistant to corrosion

Bell metal

Copper, tin (30%), lead

Casting bells

Brass

Copper, zinc

Cast and cold-worked in gears

Bronze

Copper, tin

General

Cupro-nickel

Copper, nickel (15-30%)

Very ductile, doesn't lose strength or crack when its shape is changed

Gunmetal

Copper, tin, zinc

Cast into gears, bearings

Phosphor bronze

Copper, tin, phosphorus (not a metal)

Cast to form gears and bearings where resistance to corrosion and wear is needed, as in sea water

II. Translate the passage into Ukrainian. Use the dictionary if necessary.

Aluminium bronze is among the most varied and metallurgically interesting copper alloys. This metal is the first choice – and some­times the only logical choice – for demanding applications owing to the exceptional mechanical and chemical qualities it offers, such as great strength, high hardness, excellent corrosion resistance (espe­cially in seawater and similar environments), wear resistance and superior bearing qualities as well as favourable castability, machin-ability, ductability and nonmagnetic behaviour.

Evidently, all these properties are best applied where other materials can fail too soon or will be more expensive. Aluminium bronzes find widespread applications in petrochemical plants; power generation, aircraft, automotive, railway and marine engi' neering; in iron and steel making, electrical manufacturing and building industries.

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