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1. Since what time was the preparation of metals vital to the advance of Civilization?
2. What metals did a primitive man use?
3. Why did he use gold, silver and copper?
4. How many metals do we. know today?
5. Have metals low or high melting points?
6. Are they good conductors of heat and electricity?
7.Which metal is the best conductor?
8. Does the Earth contain a large number of metals?
9. What is the most important metal?
10. How are alloys formed?
11. What properties do they possess?
12. How are metals strengthened now?
13. What depends on the availability of suitable metals and alloys?
1. Since the earliest days the preparation of metals for mechanical use was vital to the advance of civilization.
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2. Gold, silver and copper were the first to be used by a primitive man.
3. Because they were found free in nature.
4. Today we know more than sixty-five metals.
5. Metals are mostly solids at ordinary temperatures and possess comparatively high melting points with the exception of mercury.
6. They are for the most part good conductors of heat and electricity.
7. Silver is the best conductor.
8. The Earth contains a large number of metals useful to man.
9. Of all metals to be utilized in industry iron remains by far the most important.
10. To get the desirable characteristics in metals or to improve them the art to mix metals and other substances began to develop.
11. The first alloys that were formed in this way were sometimes stronger, tougher, harder and more elastic than the metals of which they were composed.
12. One of the most interesting purposes is, for instance, to make metals stronger, in other words, to strengthen them by reinforcing them with fibres.
13. Today transportation, communication, farming, construction and manufacturing all depend on the availability of suitable metals and alloys.
WORD STUDY
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un: desirable, wanted, solved, natural, limited, able
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undesirable, unwanted, unsolved, unnatural, unlimited, unable
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non: metallic, magnetic, ferrous, productive, breakable
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nonmetallic, nonmagnetic, nonferrous, nonproductive, non-breakable
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in: complete, dependent, ability, expensive, effective
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incomplete, independent, inability, inexpensive, ineffective
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im: pure, possible, perfection, patient, personal
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impure, impossible, imperfection, impatient, impersonal
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ir: regular, responsible, relative - , ,
irregular, irresponsible, irrelative - , ,
il: logical, legal - ,
illogical, illegal - ,
dis-: order, advantage, to continue, to connect, to like
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disorder, disadvantage, to discontinue, to disconnect,to dislike
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mis-: use, information, understanding, to understand
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misuse, misinformation, misunderstanding, to misunderstand
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8. , :
impure liquid -
indefinite amount -
non-ferrous metals -
irregular triangle -
inexpensive material -
non-living organism -
invisible ray -
unstable element -
non-metallic mineral -
invaluable metal -
unhardened steel -
inorganic crystal -
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9. , to make :
1. A piece of metal can be made longer and thinner when it is drawn into a fine wire and hammered into a sheet.
2. The development of physics of metals makes the field of metallurgy broader.
3. No type of heat treatment can make copper harder.
4. Such a solution will make the problem more difficult.
5. This method makes our work easier.
6. Carbon makes the physical qualities of the metal better.
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The metal is fluid. It possesses fluidity.
The metal is plastic. It possesses plasticity.
The metal is elastic. It possesses elasticity.
The metal is ductile. It possesses ductility.
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11. , :
1. to resist very high temperatures; to possess resistance to corrosion; to be resistant to deformation.
2. a strong man; a strong metal; the strength of knowledge; the strength of materials; to strengthen the resistance; to strengthen a structure
3. to conduct electricity; to conduct a research; a conductor of electricity; a conductor of a train car; the conductor of an orchestra; the conductivity of heat
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1. Above certain critical temperature, changes begin to take place in the molecular structure of a metal.
2. To prepare metals for practical use requires much knowledge and experience.
3. The aim of any research is to enlarge the possibilities which are offered by modem science.
4. In order to prevent corrosion, metals to be used in industry must be covered with special paint.
5. It is difficult to define what an amorphous material is. It may be composed of crystals which are too small to be detected.
6. This metal is too brittle to be hammered.
7. Dissimilar metals and alloys are joined to get the final product with qualities of each component. Metals and alloys to be joined are placed close together and are subjected to pressure and shock waves.
8. To strengthen metals is to reinforce them with fibres.
9. To produce changes in physical state a considerable amount of thermal energy must be supplied to metal.
10. A very good practice is to introduce the best scientific inventions into industry.
11. Toughness is the ability of a material to absorb mechanical energy by permanent deformation without breakage.
12. Steam engines were the first to be tried in aeroplanes but they were too heavy to be of any real use.
13. Steel is the metal to be formed from iron with a definite amount of carbon.
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14. If steel is heated above critical temperature, it becomes softer and much easier to be machined.
15. This alloy is not tough enough to be used in this process.
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1. Most of the metals are silvery white or grey in colour. Copper is the only red metal and gold is the only yellow one.
2. In the Universe where all is in motion and nothing is fixed, only light always has the same speed. The speed of light is the only constant quality.
3. Hardened steel is too brittle because of internal strain.
4. Aluminium has light weight and it has considerable resistance to corrosion, too.
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16. , , . .
1. The new hydroelectric station supplies energy to many industrial centres. The supplies of electrical energy in our country are very great.
2. What material will you need to build these new machine tools? A great need of metals with better properties led to creation of alloys.
3. The study of matter in a higher state of purity became a subject of vital interest to research workers. Equations that state a rule in brief form are called formulae. Our state does much for the development of science and engineering.
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The development of a number of industries is unthinkable without materials with special properties. Powder metallurgy helps to obtain such materials.
The operational principle of powder metallurgy is very well known an article of necessary size is modelled, in a mould, out of very small metal grains and is put into an electrothermic furnace where the grains get sintered together.
The coefficient of the use of metal grows by five times and the time of operation of powder articles increases greatly. The sintered articles have already shown their advantages in outer space, in deep sea conditions and inside various machines. The antivibration alloys of the "iron-copper" type made it possible to double the life of drilling tools.
This increased the labour productivity by 20 per cent. Russian scientists were the first to develop a new superhard material out of boron nitride. The priority of Russia in developing the first article out of so-called viscous ceramics has been recognized in many countries.
There is another method when powder is sprayed onto the worn-our metal parts. The spraying of powder on articles made of usual steel makes them highly heat-resistant and much stronger. Their reliability and length of service increases. The powder is pressurized, melted and sprayed in a thin layer on different metal parts. Such a coating saves
metal from corrosion for a period of 25 years.
18. , , a:
1. Powder metallurgy helps to obtain
a) conventional steel; b) drilling tools; c) superhard materials
2. The advantages of powder metallurgy are
a) to save metals from corrosion;
b) to sinter small metal grains together;
c) to increase the labour productivity;
d) to spray the powder onto other metal parts;
e) to increase the time of operation of sintered articles.
Revision Exercise
, :
1. Mendeleyev predicted that there must exist a few unknown elements with quite definite properties.
2. Our country has a lot of chemical research institutes.
3. Did it take you much time to complete the experiment last week? Yes, it took us a great deal of time.
4. I think you have to change a little the approach to the problem.
5. Russian metallurgists work a great deal to develop new metals and alloys. And still there are plenty of problems to solve in metallurgy.
6. A large number of research workers has been trained in Russia.
7. Many listeners from abroad are corresponding with Moscow Radio.
8. Much time has passed since the days when the first TV station began to operate in Russia.
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GRAMMAR STUDY
4. Participles I II :
) : to indicate indicating (Participle I)
1. to develop - developing, to contain - containing, to heat - heating, to purify - purifying, to perform - performing
2. to define - defining, to increase - increasing, to improve - improving, to rise - rising, to lecture - lecturing
3. to get - getting, to run - running, to sit - sitting, to cut - cutting
4. to tie - tying, to lie - lying, to die - dying
6) : to solve solved; to break broken (Participle II)
1. to cross - crossed, to mount - mounted, to improve - improved, to increase - increased, to purify - purified, to apply - applied
2. to make - made, to read - read, to find - found, to teach - taught, to burn - burnt, to build - built, to deal - dealt
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3. to do - done, to be been, to see - seen, to show - shown, to speak - spoken, to draw - drawn, to take - taken
4. to cut - cut, to put - put, to forecast forecast, to broadcast - broadcast, to cost - cost, to let - let
International Words
6. He , , . :
)classification-
economics -
horizontal -
literature -
metrology -
pedagogical -
publication -
theoretical -
theory -
vertical -
) analyse -
calculation -
combine -
group -
medal -
order -
organic -
sphere -
system -
7. A. .
