5. , :
1. What is the most important metal?
2. What mechanical properties of metals do you know?
3. What is strength?
4. What is ductility? 5. What is malleability?
a. The capacity of a metal to be permanently deformed in tension without breaking. b. Iron.
c. The capacity of a metal to be deformed by compression without rupture.
d. The property of a metal to resist to external loads.
e. Hardness, ductility and malleability.
6. , :
1. The most important metal in use today is.... a) carbon;
b) iron;
c) some other metal.
2. Ductility is the capacity of a metal... a) to be permanently deformed in tension
without breaking;
3. Malleability is the capacity of a metal b) to be permanently deformed by
compression without rupture;
4. The strength of a metal is the property c) to resist to external loads and stresses.
2
1. :
1. ferrous rnetals a.
2. cast iron b.
3. carbon content c.
4. alloy steel d.
5. carbon steel e. ( )
6. strength f.
7. hardness g.
8. ductility h.
9. machinability i.
10. resistance to wear j.
11. conductivity k.
12. iron l.
13. silicon m.
14. alloy n.
15. rust-resistant o.
2. :
metal, element, industry, steel, material, industrial, electronic, magnetic, type, chemical, mechanical, rocket, automobile.
3. :
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 kinds 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. Strength, 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.
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7. According to their chemical and mechanical properties steels may be used in different branches of industry, for example, in machinebuilding, rocket engineering, automobile industry, etc.
1,4,5,6.
5. , :
1. What elements do ferrous metals consist of?
2. What is carbon steel?
3. What are alloy steels?
4. What are the most important properties of steel?
5. In what branches of industry are steels used?
a. Steels in which in addition to carbon an alloying element is present
b. In machinebuilding, automobile industry, etc.
c. Of iron combined with carbon, silicon and other elements.
d. It contains only iron and carbon.
e. Strength, ductility and machinability.
6. , :
1. Alloys consist of.... a) steel and cast iron;
b) iron and stainless steel,
c) simple metal and some other element.
2. Carbon steel contains.... a) steel and cast iron;
b) iron, carbon, an alloying element;
3. Alloy steels include.... c) only iron and carbon
4. The most important properties of steel are a) electrical conductivity, resistance to wear,
magnetic properties;
b) strength, ductility, machinability.
3
1. :
1.lustre a.
2. property b.
3. quantity c.
4. conductivity d.
5. solid e.
6. brittle f.
7. undergo g.
8. to protect h.
9. environment i.
10. alloy j.
11. poor conductor k.
12. distinction l.
13. strength m.
14. hardness n.
2. :
metal, metallic, electricity, electric, fact, group, rocket, element, material, corrosion, chemical, electromechanical, organic, barrier, ii
3. :
METALS AND NONMETA15
1. There are some distinctions between metals and nonmetals, are distinguished from nonmetals by their high conductivity for h electricity, by metallic lustre and by their resistance to electric Their use in industry is explained not only "By those properties 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
3. The so-called precious metals include silver, gold, platinum and palladium. The light metals are aluminium, berillium 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 brittle materials without metallic lustre and are usually poor conductors of electricity. Nonmetals show greater variety of chemical properties than common metals do.
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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.
