V. Fill in the gaps.

1. Ferrous metals are … of iron … carbon, manganese, silicon and other components.

2. People use various metals … machine-building … .

3. We can divide all … elements … metals and non-metals.

4. Steel and cast iron are … the group of … metals.

VI. Fill in the table with the following engineering materials: iron, glass, aluminium, wood, cast iron, plastic, copper, steel, rubber.

	METALS	NON-METALS
a) FERROUS	1. 2. 3.	1. 2. 3. 4.
b) NON-FERROUS	1. 2.

Activity

I. Ask your groupmates what materials the following objects are made of.

a beaker, a bolt, a pipe, a wire, a cylinder, gloves, shelves, nuts, screws

II. Give answers to the given questions and reproduce the dialogue with your partner.

• There are two kinds of engineering materials, aren't there?

• … .

• What are they?

• … .

• Can you give me any examples of non-metals?

• Sure. … .

• Are engineering materials widely used?

• Certainly. … .

III. Name the objects around you and say what materials they are made of.

Writing

I. Describe this tank according to the information from the table.

	part of the tank	material	its quality
	1. sides 2. lid 3. pipe at the top 4. pipe at the bottom	steel rubber plastic copper	strong tough light heavy

II. Translate the passage into Russian.

Chemical elements are metals or non-metals. They are widely used in making tools, instruments and devices. Metals and non-metals have different properties.

The combination of metals and non-metals is known as an alloy. For example, steel is an alloy of iron and carbon. The alloy of copper and zinc is known as brass. The properties of alloys are often better than the properties of their constituents. That is why the majority of engineering products are made of various alloys.

Section b. Properties of Engineering Materials Lead-in

I. A) Why is it important for an engineer to know the properties of engineering materials?

b) List the properties you know. Compare your list with that of your fiend.

II. A group of students is at the practical class now. Listen to their conversation and learn how we can compare properties of various materials.

1. Paul: Alex, help me, please. This pipe is very heavy.

Alex: Is it really? What material is it made of?

Paul: Actually, it is made of metal.

Alex: Why is it made of metal?

Paul: Well, because it is a strong material. In any case, it is stronger and more rigid than rubber.

Alex: Is it an expensive material?

Paul: Yes, it is. It is the most expensive material, as a matter of fact.

2. Alice: Paul, take that pipe, please. It is rather light.

Paul: Oh! It is very light. What material if it made of?

Alice: It is made of plastic.

Paul: Why is it made of plastic?

Alice: Well, it is a rigid material, but it is less flexible than rubber. In fact, it is the lightest and the least expensive material.