Вступ до методичних рекомендацій

Ex. 13Answer the questions:

1. 
   What are the main two groups of metals?
   
2. 
   What elements do ferrous metals consist of?
   
3. 
   What is the difference between iron and steel?
   
4. 
   What is casting?
   
5. 
   What do we call the shop where metals are casted?
   
6. 
   Why is steel widely used in machine – building?
   
7. 
   What are the main types of iron castings?
   

V. Oral Practice


Ex. 14. Speak on the following problems:

1. 
   1.Casting as the process.
   
2. 
   The characteristics of grey iron casting.
   
3. 
   The comparison of grey iron casting with other casting metals.
   
4. 
   The difference between iron and steel.
   

Ex15. Topic “Ferrous metals”

Different metals are widely used in the machine-building industry. There are two groups of metals: ferrous metals and non-ferrous metals. Say a few words about ferrous metals giving information on:

1. 
   The composition of metals.
   
2. 
   The using of metals in industry.
   
3. 
   The process of casting.
   
4. 
   The shop where metals are cast.
   
5. 
   Steel and its contents.
   
6. 
   The composition of cast iron
   
7. 
   Grey iron and its characteristics.
   
8. 
   The comparison of grey iron with other casting metals.
   
9. 
   The using of malleable iron castings.
   

VI. Reading and comprehension.


Ex. 16. Read the text B without a dictionary for 7 minutes and say what problems are mentioned in the text:
Text B
Where metals come from
Metals are most often found in rocks on the Earth. Metals are sometimes found in sand because sand is rock that is worn away over a long time. Most often metals are in the form of ore. Ores are a kind of rock with very small pieces of metal inside. To get the metal out, the ore is crushed and sometimes heated or chemicals are used. The places where people get metals from the Earth are called mines. People sometimes dig mines making big holes in the ground, to get at the ore. Many things that are made of metals may, in fact, be made of mixtures of at least one metal with either other metals, or with non-metals. These mixtures are called alloys. Some common alloys are:
Steel (iron and carbon) (Carbon is a non-metal)
Brass (copper and zinc)
Bronze ( copper and tin)
People first began making things from metal over 6000 years ago, when they discovered how to get copper from its ore. They then learned how to make a harder alloy, bronze, by adding tin to the copper. About 3000 years ago, they discovered iron. By adding small amounts of carbon to iron, they found that they could make a particularly useful alloy – steel. Iron and the large family of iron alloys called steel are the most common of the commercial metals. Iron melts at 2,777 F and boils at 4,442 f. Small addition of carbon reduces the melting point.
Ore – руда crush – вижимати mine - шахта, копальня brass – жовта мідь cooper – мідь tin – олово