Ferrous metals and steels.

1. Ferrous metals consist of iron combined with carbon, silicon and other elements. But carbon is 

the most important element in ferrous alloys.

2. Ferrous metals are used in industry in two forms: steel and cast iron, which differ in the  

quantity of carbon content.

3. Alloys consist of a simple metal combined with some other element. Steel is a ferrous material 

having some carbon content. There are two kids of steel: carbon steel and alloy steels.

4. Carbon steel should contain only iron and carbon without any other alloying element.

5. Alloy steels are those in which in addition to carbon an alloying element is present. These 

alloying elements have an effect on the properties of steel. They increase its strength and 

hardness, for example, high percentage of chromium makes steel rust-resistant, and we call it

“stainless steel”.

6. Strengthm, ductility and machinability are the most important industrial and commercial

properties of steel. Such properties as resistance to wear, electrical conductivity, magnetic

properties are important in special uses of metals.

7. According to their chemical and mechanical properties steel may be used in different branches 

of industry, for example, in machinebuilding, rocket engineering, automobile industry, ets.

Answer the questions:

1. What elements do ferrous metals consist of?
2. What is carbon steel?
3. What are alloy steel?
4. What are the most important properties of steel?
5. In what branches of industry are steels used?

Find Russian words in the right column:

1. ferrous                       a. проводимость

2. cast iron                     b. углеродистая сталь

3. carbon content           c. износостойкость

4. alloy steel                  d. прочность

5. carbon steel               e. обрабатываемость             

                                          (на станке)

6. strength                      f. жесткость

7. hardness                     g. железо

8. ductility                      h. сплав

9. machinability              i. черные металлы

10. resistance to wear     j. чугун

11. conductivity             k. содержание

                                           углерода

12. iron                           l. ковкость

13. silicon                      m. легированная  

                                            сталь

14. alloy                         n. кремний

15. rust-resistant            o. нержавеющий

 

Complete the following sentences:  

1. The most important metal a) carbon;

in use today is …                 b) iron;

                                             c) some other  metal.

 

2. Ductility is the capacity  a) to be 

of a metal …                     permanently                                                     

                                              deformed

                                              in tension without                             

                                              breaking;

 

3. Malleability is the capa- b) to be permanently

 city of a metal …                 deformed

                                              by compression              

                                         without

4. The strength of a metal   rupture;

is the property …                    c) to resist to externa

                                               and stresses.

 

Text 5.

Metals and nonmetals.

1. There are some distinctions between metals and nonmetals. Metals are distinguished from nonmetals by their high conductivity for heat and electricity, by metallic luster and by their resistance to electric current. Their use in industry is explained not only by those properties, but also by the fact that their properties, such as strength and hardness, can be greatly improved by alloying them with other metals.

2. There are several important groups of metals and alloys. The common metals such as iron, copper, zinc, etc are produced in great quantities.

3. The so-called precious metals include silver, gold, platinum and palladium. The light metals are aluminium, beryllium and titanium. They are important in aircraft and rocket construction.

4. Many elements are classified as semimetals (bismuth, for example) because they have much poorer conductivity than common metals.

5. Nonmetals (carbon, silicon, sulphur) in the solid state are usually brittie materials without metallic lustre and are usually poor conductors of electricity. Nonmetals show greater variety of chemical properties than common metals do.

6. Metals can undergo corrosion, changing in this case their chemical and electromechanical properties. In order to protect metals from corrosion the products made of metals and steel are coated by some films (coatings). Organic coatings protect metals and steel from corrosion by forming a corrosion-resistant barrier between metal or steel and the corrosive environment.

Answer the questions:

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