Загрузил Liana Tschagan

Чистякова ресурс 1

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Министерство образования
и науки Российской Федерации
М.А. Чистякова
ENGLISH FOR METALLURGISTS
Учебный электронный текстовый ресурс
Учебное пособие по английскому языку для специальных целей
Предназначено для студентов всех уровней подготовки
направления 22.03.02 Металлургия
Екатеринбург
2016
CONTENTS
UNIT 1. THE ORIGINS OF METALLURGY ................................................................................ 4
1.
Words to remember ............................................................................................................... 5
2.
Open the brackets using Passive Voice ................................................................................ 5
3.
Questions for discussion ....................................................................................................... 6
4.
Make a summary about the main events in the history of metallurgy ................................ 6
UNIT 2. THE METALLURGICAL INDUSTRY ........................................................................ 7
1.
Make nouns from these adjectives ....................................................................................... 8
2.
Match the synonymous phrases ........................................................................................... 8
3.
Complete the sentences with the words and phrases from ex.3 .......................................... 9
4.
Open the brackets and use the Passive Voice ...................................................................... 9
5.
Questions for discussion ....................................................................................................... 9
UNIT 3. NON-FERROUS METALS .............................................................................................. 10
1.
Read the text and say what the difference between non-ferrous and ferrous metals is? . 10
2.
Words to remember ............................................................................................................. 10
3.
Answer the questions .......................................................................................................... 10
4.
Read the text about aluminium .......................................................................................... 11
5.
Match the synonymous expressions ................................................................................... 11
6.
Discuss the questions .......................................................................................................... 11
7.
Skim the following text to find out the most common uses of aluminium. ...................... 12
8.
Summarise the main uses of aluminium ........................................................................... 12
10.
Words to remember ......................................................................................................... 13
11.
Match the synonymous expressions ............................................................................... 14
12.
Answer the questions ...................................................................................................... 14
13.
Read the text about nickel and fill in the missing words ............................................... 14
14.
Answer the questions ...................................................................................................... 14
15.
Read and translate the text about precious metals. ....................................................... 15
16.
Words to remember ......................................................................................................... 15
17.
Turn British units of measurement (ft – foot and in – inch) into metric units ............ 16
18.
Match the synonymous expressions ............................................................................... 16
19.
Discuss the questions ...................................................................................................... 16
20.
Read the text about refractory metals ............................................................................ 16
21.
Words to remember ......................................................................................................... 17
22.
Discuss the questions ...................................................................................................... 17
2
23.
Read and translate the texts about tin and zinc ............................................................. 17
24.
Words to remember ......................................................................................................... 18
25.
Match the synonyms ....................................................................................................... 18
26.
Discuss the questions ...................................................................................................... 18
UNIT 4. IRON ................................................................................................................................... 19
1.
Read the text about iron paying attention to the metallurgical terms. Explain the
italicized phrases. .................................................................................................................................... 19
2.
Words to remember ............................................................................................................. 20
3.
Fill in the linking words in the following sentences: ........................................................ 20
4.
Discuss the questions .......................................................................................................... 20
UNIT 5. FERROUS METALS ........................................................................................................ 22
1.
Read the first part of the text about ferrous metals paying attention to the metallurgical
terms. Explain the italicized phrases...................................................................................................... 22
2.
Words to remember ............................................................................................................. 23
3.
Discuss the questions .......................................................................................................... 23
4.
Read the second part of the text about ferrous metals paying attention to the
metallurgical terms. Explain the italicized phrases. .............................................................................. 23
5.
Words to remember ............................................................................................................. 24
6.
Discuss the questions .......................................................................................................... 24
7.
Compare different materials. Use comparative and superlative adjectives ...................... 25
3
UNIT 1. THE ORIGINS OF METALLURGY
Metallurgy is a field of materials science that studies the physical and
chemical behavior of metallic elements, their intermetallic compounds, and their
mixtures, which are called alloys. It is also the technology of metals: the way in
which science is applied to their practical use.
The first evidence of human metallurgy dates from the 5th and 6th
millennium BC, and was found in the archaeological sites of Serbia. To date, the
earliest copper smelting is found at the Belovode site, these examples include a
copper axe from 5500 BC. Other signs of human metallurgy are found from the third
millennium BC in places like Palmela (Portugal) and Stonehenge (United Kingdom).
Silver, copper, tin and meteoric iron can also be found native, allowing a
limited amount of metalworking in early cultures. Egyptian weapons were made from
meteoric iron in about 3000 BC. However, by learning to get copper and tin by
heating rocks and combining those two metals to make an alloy called bronze, the
technology of metallurgy began about 3500 BC with the Bronze Age.
The extraction of iron from its ore into a workable metal is much more
difficult. It appears to have been invented in about 1200 BC, beginning the Iron Age.
Historical developments in ferrous metallurgy can be found in a wide variety of
past cultures and civilizations. These include the ancient and medieval kingdoms and
empires of the Middle East and Near East, ancient Iran, ancient Egypt, ancient Nubia,
and Anatolia (Turkey). Many applications, practices, and devices associated or
involved in metallurgy were established in ancient China, such as the innovation of
the blast-furnace and cast iron.
(Source: http://en.wikipedia.org/wiki/Metallurgy)
4
1. Words to remember
Compound – смесь, соединение
Alloy – сплав
Copper – медь
Silver – серебро
Tin – олово Iron – железо
Smelting, smeltery – плавильня
Ore – руда
Blast-furnace – доменная печь
Cast-iron – чугун
Bellows – воздуходувные мехи
Present Simple Passive
2. Open the brackets using Passive Voice
is
are
+ V ed/ V3
Past Simple Passive
A. The first evidence of human
was
metallurgy ____________ (find) in Serbia.
were
+ V ed/ V3
B. To date, the earliest copper smelting ____________ (find) at the
Belovode site.
C. Other signs of human metallurgy __________ (find) in Palmela and
Stonehenge.
D. Egyptian weapons ____________ (make) from meteoric iron.
E. The extraction of iron from its ore __________ (invent) in about
1200 BC.
F. Many metallurgical applications, practices, and devices ___________
(establish) in ancient China.
G. Blast furnace _______________ (invent) in China.
5
3. Questions for discussion
A. What is metallurgy?
B. What is an alloy?
C. When did metallurgy appear?
D. What did people learn to do in the Bronze Age?
E. What did people invent in the Iron Age?
F. Where can we find historical developments of ferrous metallurgy?
G. What metallurgical applications and devices were invented in ancient
China?
H. Which devices were used in ancient China to make the furnace operate?
4. Make a summary about the main events in the history of metallurgy
6
UNIT 2. THE METALLURGICAL INDUSTRY
The metallurgical industry can be broadly divided into primary, secondary and
miscellaneous metal production operations. Primary refers to the production of metal
from ore. Secondary refers to production of alloys from ingots and to recovery of
metal from scrap. Miscellaneous metal production includes industries that produce or
use metals for final products.
The task of the metallurgist is to achieve balance between material properties
such as cost, weight, strength, toughness, hardness, corrosion and fatigue resistance,
and performance in temperature extremes. To achieve this goal, the operating
environment must be carefully considered. In a saltwater environment, ferrous metals
and some aluminium alloys corrode quickly. Metals exposed to cold or cryogenic
conditions may endure a ductile to brittle transition and lose their toughness,
becoming more brittle and prone to cracking. Metals under continual cyclic loading
can suffer from metal fatigue. Metals under constant stress at elevated temperatures
can creep.
The primary metals industry consists of both ferrous and nonferrous
operations. These processes are characterised by emission of large quantities of sulfur
oxides and particulate. The major air contaminant from secondary metallurgical
process is particulate in the forms of metallic fumes, smoke and dust.
Air pollution is prevented by capturing the smoke, dust, and fumes at the
furnace and transporting these contaminants to suitable control devices.
Source: https://en.wikipedia.org/wiki/Metallurgy
7
1. Words to remember
Ingot – cлиток, брусок
Scrap – металлический лом, скрап
Toughness – упругость, прочность
Hardness – твердость, прочность
Ferrous metals – черные металлы
Non-ferrous metals – цветные металлы
Fatigue resistance – износостойкость
Ductile – гибкий, ковкий, тягучий
Brittle – ломкий, хрупкий
Cracking – трескание
Particulate - частицы
Contaminant – загрязнитель
Furnace – печь, горн
1. Make nouns from these adjectives
Strong –
Hard –
Tough –
Ductile –
Brittle –
Resistance –
2. Match the synonymous phrases
Exposed to cold
right and proper
Miscellaneous
tend to crack
Refers to
not protected from cold
Suitable
various
Prone to cracking
means
8
3. Complete the sentences with the words and phrases from ex.3
A. The metallurgical industry is divided into primary, secondary and
_______________ metal production operations.
B. Primary metallurgy ______________ the production of metal from ore.
C. Metals __________________ or cryogenic conditions lose their
toughness, becoming more brittle and _________________.
D. To prevent air pollution it is necessary to capture the smoke, dust, and
fumes
at
the
furnace
and
transport
these
contaminants
to
_____________ control devices.
4. Open the brackets and use the Passive Voice
A. The metallurgical industry_____________ (divide) into primary, secondary
and miscellaneous metal production operations.
B. Ferrous and nonferrous operations ________________ (characterise) by
emission of particulate.
C. Air pollution ___________ (prevent) by capturing the smoke, dust, and fumes
at the furnace
5. Questions for discussion
A. What is primary metallurgy?
B. What is secondary metallurgy?
C. What kind of balance should be achieved in metal production?
D. What do ferrous metals do in a saltwater environment?
E. What do metals do in cold or cryogenic conditions?
F. What are the main ecological problems in primary metal industry?
G. What is the major air contaminant from secondary metallurgical industry?
H.
What are the ways to prevent air pollution in metallurgical industry?
9
UNIT 3. NON-FERROUS METALS
1. Read the text and say what the difference between non-ferrous and ferrous
metals is?
Non-ferrous metals are metals that do not contain iron. There are two groups of
metals; ferrous and non-ferrous. Ferrous metals contain iron, for example carbon
steel, stainless steel (both alloys; mixtures of metals) and wrought iron.
Non-ferrous metals don't contain iron, for example aluminium, brass, copper
(which can be remembered as ABC) and titanium. You can also get non-ferrous
metals as alloys e.g., brass is an alloy of copper and zinc.
Non-ferrous metals are specified for structural applications requiring reduced
weight, higher strength, nonmagnetic properties, higher melting points, or resistance
to chemical and atmospheric corrosion. They are also specified for electrical and
electronic applications. (Source: engineershandbook.com›Materials/nonferrous.htm)
2. Words to remember
non-ferrous metals – цветные металлы
ferrous metals – черные металлы
iron – железо
carbon steel – углеродистая сталь
stainless steel – нержавеющая сталь
alloy – сплав
wrought iron – кованое железо
copper – медь
brass – латунь
silicon – кремний
3. Answer the questions
A. What is a non-ferrous metal? Give examples.
B. Which metals are called ferrous? Give examples.
C. What are the properties of non-ferrous metals?
D. Where are non-ferrous metals used?
10
4. Read the text about aluminium
Non-Ferrous Metals include:
Aluminum
Pure aluminum is a silvery-white metal with many desirable characteristics. It is
light, nontoxic (as the metal), nonmagnetic and non-sparking. It is easily formed,
machined, and cast. Pure aluminum is soft and lacks strength, but alloys with small
amounts of copper, magnesium, silicon, manganese, and other elements have very
useful properties.
Aluminum is an abundant element in the earth's crust, but it is not found free in
nature. The Bayer process is used to refine aluminum from bauxite, an aluminum ore.
Because of aluminum's mechanical and physical properties, it is an extremely
convenient and widely used metal.
(Source: engineershandbook.com›Materials/nonferrous.htm)
5. Match the synonymous expressions
a. desirable characteristics
is not strong enough
b. lacks strength
helpful
c. abundant element
to make pure aluminium
d. to refine aluminium from bauxite
useful properties
e. convenient
element available in large quantities
6. Discuss the questions
A. What are the properties of aluminium?
B. What is the difference between pure aluminium and its alloys?
C. How can you get aluminium from nature?
11
7. Skim the following text to find out the most common uses of aluminium.
Some Common Uses of Aluminium:
Building & Construction Industry:
─
door and window frames
─
wall cladding, roofing, awnings
Manufacture of Electrical Products:
─
high tension power lines, wires, cables
─
components for television, radios, refrigerators and air-conditioners
Cooking Utensils:
─
kettles and saucepans
Aeronautical, Aviation & Automotive Industries:
─
propellers
─
airplane and vehicle body sheet
─
gearboxes, motor parts
Leisure Goods:
─
tennis racquets, softball bats
─
indoor and outdoor furniture
(Source: engineershandbook.com›Materials/nonferrous.htm)
8. Summarise the main uses of aluminium
Aluminium is used in…
Aluminium is used to make…
12
Read the texts about copper
Copper
Copper provides a diverse range of properties: good thermal and electrical
conductivity, corrosion resistance, ease of forming, ease of joining, and colour.
However, copper and its alloys have relatively low strength at elevated temperatures.
Some copper alloys are also susceptible to stress-corrosion cracking unless they are
stress relieved.
Next to silver, copper is the next best electrical conductor. It is a yellowish red
metal that polishes to a bright metallic luster. It is tough, ductile and malleable.
Copper has an unpleasant taste and a peculiar smell. Copper is resistant to corrosion
in most atmospheres including marine and industrial environments. It is corroded by
oxidizing acids, halogens, sulphides and ammonia based solutions.
Copper and its alloys – the brasses and bronzes – are available in rod, plate, strip,
sheet, tube shapes, forgings, wire, and castings.
(Source: engineershandbook.com›Materials/nonferrous.htm.)
10. Words to remember
Cracking – трескание
Luster – блеск
Ductile – податливый, ковкий, тягучий
Malleable – ковкий, податливый
Solution – раствор
Forging – ковка
Rod – стержень
Plate – пластина
Strip – лента
Sheet – лист
Tube – труба
Wire – проволока
Casting – литье
13
11. Match the synonymous expressions
diverse
higher than normal temperature
elevated temperature
to suffer from
to be susceptible
different
marine
air, water and land around us
environment
connected with the sea
available
able to be used
12. Answer the questions
A. What are the properties of copper?
B. What are the disadvantages of some copper alloys?
C. Where are copper and its alloys used?
13. Read the text about nickel and fill in the missing words
properties
elevated
strength
Nickel
Nickel fits many applications that require specific corrosion resistance or
_________________ temperature strength. Some nickel alloys are among the
toughest structural materials known. When compared to steel, other nickel alloys
have ultrahigh________________ and high moduli of elasticity. Commercially pure
nickel has good electrical, magnetic, and magnetostrictive __________________.
(Source: engineershandbook.com›Materials/nonferrous.htm)
14. Answer the questions
A. What are the properties of nickel?
B. Where is nickel used?
14
15. Read and translate the text about precious metals.
Precious Metals
Gold is an extremely inert, soft, ductile metal that undergoes very little
work hardening. A gram of pure gold can be worked into a leaf covering 6 per
2 feet and only 0.0000033 inches thick. It is used chiefly for linings or
electrodeposits and is often alloyed with other metals such as copper or nickel
to increase strength or hardness.
Silver is a very malleable, ductile, and corrosion resistant metal that has
the highest thermal and electrical conductivity of all metals and is the least
costly of all the precious metals. Alloyed with copper, and sometimes with
zinc, silver is also used in high-melting temperature solders.
Platinum is an extremely malleable, ductile, and corrosion resistant
silver-white metal. When heated to redness, it softens and is easily worked. It
is nearly non-oxidizable and is soluble only in liquids that generate free
chlorine. Because platinum is inert and stable, even at high temperatures, the
metal is used for high-temperature handling of high-purity chemicals and
laboratory materials. Other applications include electrical contacts, resistance
wire, thermocouples, and standard weights.
(Source: engineershandbook.com›Materials/nonferrous.htm)
16. Words to remember
Lining – обкладка, облицовка
Deposit – осадок, отложение
Solder – припай
Soluble – растворимый
Liquid – жидкость
Thermocouple – термопара
15
17. Turn British units of measurement (ft – foot and in – inch) into metric
units
1 foot  30.5 cm
1 inch = 2.5 cm
6 ft = ?
0.0000033 in = ?
18. Match the synonymous expressions
Precious metal
expensive
To increase
to deal with
Costly
practical use
To handle
noble metal
Application
to become larger
19. Discuss the questions
A. What are the properties of gold?
B. Where is gold used?
C. Why is gold often alloyed with copper or nickel?
D. Which metal is less expensive of all precious metals?
E. Which precious metal is the best electrical and thermal conductor?
F. What are the properties of platinum?
G. Where is platinum used?
20. Read the text about refractory metals
Refractory Metals
Refractory metals are characterized by their extremely high melting points,
which range well above those of iron, cobalt, and nickel. They are used in demanding
applications requiring high-temperature strength and corrosion resistance. The most
extensively used of these metals are tungsten, tantalum, molybdenum, and
columbium (niobium).
(Source: engineershandbook.com›Materials/nonferrous.htm)
16
21. Words to remember
Refractory metals – огнеупорные (тугоплавкие) металлы
Melting point – точка плавления
Tungsten – вольфрам
22. Discuss the questions
A. What is a refractory metal?
B. Give examples of refractory metals.
C. What are the properties of refractory metals?
23. Read and translate the texts about tin and zinc
Tin
Tin is characterized by a low-melting point (450°F), fluidity when molten,
readiness to form alloys with other metals, relative softness, and good formability.
The metal is nontoxic, solderable, and has a high boiling point. The temperature
range between melting and boiling points exceeds that for nearly all other metals
which facilitates casting. Upon severe deformation, tin and tin-rich alloys soften.
Principal uses for tin are as a constituent of solder and as a coating for steel. Tin is
also used in bronze and pewter.
Zinc
Zinc, a crystalline metal with moderate strength and ductility, is seldom used
alone except as a coating. In addition to its metal and alloy forms, zinc also extends
the life of other materials such as steel, rubber, plastics and wood. Zinc is also used to
make brass, bronze, and die-casting alloys in plate, strip, and coil; superplastic zinc
activators and stabilizers for plastics.
(Source: engineershandbook.com›Materials/nonferrous.htm)
17
24. Words to remember
Boiling point - точка кипения
Coating – слой, покрытие
Pewter – олово, сплав олова со свинцом
Die-casting – пресс-литье
Coil – катушка
Foundry – 1) литейная, литейный завод, 2) литейное дело
25. Match the synonyms
Facilitate
main
Principal
make easier
Constituent
rarely
Seldom
component
Extend
make bigger or longer
26. Discuss the questions
A. What are the properties of tin?
B. What makes the process of casting tin easier?
C. What are the main applications of tin?
D. What are the properties of zinc?
E. When is zinc used alone?
18
UNIT 4. IRON
1. Read the text about iron paying attention to the metallurgical terms.
Explain the italicized phrases.
Iron is a chemical element with the symbol Fe (from Latin: ferrum) and
atomic number 26. It is the most common element (by mass) forming the planet Earth
as a whole, forming much of Earth's outer and inner core. It is the fourth most
common element in the Earth's crust. Iron's very common presence in rocky planets
like Earth is due to its abundant production as a result of fusion in high-mass stars.
Like other group 8 elements, iron exists in a wide range of oxidation states, −2
to +8, although +2 and +3 are the most common.
Iron metal has been used since ancient times, though lower-melting copper
alloys were used first in history. Pure iron is soft (softer than aluminium), but is
unobtainable by smelting. The material is significantly hardened and strengthened by
impurities from the smelting process, such as carbon. A certain proportion of carbon
(between 0.2 % and 2.1 %) produces steel, which may be up to 1000 times harder
than pure iron. Crude iron metal is produced in blast furnaces, where ore is reduced
by coke to cast iron, which has a high carbon content. Further refinement with
oxygen reduces the carbon content to the correct proportion to make steel. Steels and
low carbon iron alloys with other metals (alloy steels) are by far the most common
metals in industrial use, due to their great range of desirable properties.
Iron chemical compounds, which include ferrous and ferric compounds, have
many uses. Iron oxide mixed with aluminium powder can be ignited to create a
thermite reaction, used in welding and purifying ores. It forms binary compounds
with the halogens and the chalcogens.
Iron is the most widely used of all the metals, accounting for 95 % of
worldwide metal production. Its low cost and high strength make it indispensable in
engineering applications such as the construction of machinery and machine tools,
automobiles, the hulls of large ships, and structural components for buildings. Since
pure iron is quite soft, it is most commonly used in the form of steel.
Source: engineershandbook.com›Materials/ferrous.htm
19
2. Words to remember
Core – ядро
Earth’s crust – земная кора
Impurities – примеси
Crude – грубый
Coke – кокс
Refinement – очищение
Ignite – воспламенять
Welding – сварка
3. Fill in the linking words in the following sentences:
like
since
such as
though
due to
A. _________other group 8 elements, iron exists in different oxidation states.
B. Iron metal has been used since ancient times, __________ copper alloys were
used first in history.
C. Steels and low carbon iron alloys are widely used in industry _________ their
desirable properties.
D. Iron is indispensable in engineering applications ___________ the construction
of machinery and machine tools, automobiles, and structural components for
buildings.
E. ___________ pure iron is quite soft, it is most commonly used in the form of
steel.
4. Discuss the questions
A. What is iron?
B. What are the different oxidation states of iron?
20
C. What are the properties of iron?
D. When was iron first used in human history?
E. How is crude iron produced?
F. Where is iron used?
G. Why is iron so vital in engineering applications?
21
UNIT 5. FERROUS METALS
1. Read the first part of the text about ferrous metals paying attention to
the metallurgical terms. Explain the italicized phrases.
Commercially available iron is classified based on purity and the abundance of
additives. Pig iron has 3.5–5 % carbon and contains varying amounts of
contaminants such as sulfur, silicon and phosphorus. Pig iron is not a saleable
product, but rather an intermediate step in the production of cast iron and steel from
iron ore. Cast iron contains 2–4 % carbon, 1–6 % silicon, and small amounts of
manganese.
Contaminants present in pig iron that negatively affect material properties,
such as sulfur and phosphorus, have been reduced to an acceptable level. It has a
melting point in the range of 1420–1470 K. Its mechanical properties vary greatly,
dependent upon the form carbon takes in the alloy.
“White” cast irons contain their carbon in the form of cementite, or iron
carbide. This hard, brittle compound dominates the mechanical properties of white
cast irons, rendering them hard, but unresistant to shock. The broken surface of a
white cast iron is full of fine facets of the broken carbide, a very pale, silvery, shiny
material, hence the appellation.
Wrought iron contains less than 0.25 % carbon. It is a tough, malleable
product, but not as fusible as pig iron. Wrought iron is characterized by the presence
of fine fibers of slag entrapped in the metal. Wrought iron is more corrosion
resistant than steel. It has been almost completely replaced by mild steel for
traditional “wrought iron” products and blacksmithing.
Source: engineershandbook.com›Materials/ferrous.htm
22
2. Words to remember
Pig iron – чушковый чугун
Cast iron – чугун
Melting point – точка плавления
Fine facets – тонкие грани / фацеты
Fusible – плавкий
Slag – шлак
Blacksmithing – кузнечное дело; изделия кузнечного дела
3. Discuss the questions
A. What is pig iron?
B. Is pig iron good for sale?
C. What is cast iron?
D. What is white cast iron?
E. What is wrought iron?
F. What are the properties of wrought iron?
4. Read the second part of the text about ferrous metals paying attention
to the metallurgical terms. Explain the italicized phrases.
Mild steel corrodes more readily than wrought iron, but is cheaper and more
widely available. Alloy steels contain varying amounts of carbon as well as other
metals, such as chromium, vanadium, molybdenum, nickel, tungsten, etc. Their alloy
content raises their cost, and so they are usually only employed for specialist uses.
One common alloy steel, though, is stainless steel. Recent developments in ferrous
metallurgy have produced a growing range of microalloyed steels, also termed
23
'HSLA' or high-strength, low alloy steels, containing tiny additions to produce high
strengths and often spectacular toughness at minimal cost.
Apart from traditional applications, iron is also used for protection from
ionizing radiation. Although it is lighter than another traditional protection material,
lead, it is much stronger mechanically.
The main disadvantage of iron and steel is that pure iron, and most of its
alloys, suffer badly from rust if not protected in some way. Painting, galvanization,
passivation, plastic coating and bluing are all used to protect iron from rust by
excluding water and oxygen or by cathodic protection.
(Source: engineershandbook.com›Materials/ferrous.htm)
5. Words to remember
Mild steel – мягкая малоуглеродистая сталь, свариваемая сталь
Alloy steel – легированная сталь
Lead – синец
Rust – ржавчина
Galvanization – оцинковывание
Passivation – пассивация, поверхностная протравка, декапировка
Plastic coating – пластиковое покрытие
Bluing – воронение
6. Discuss the questions
A. What are the different types of steel?
B. What does “HSLA” stand for?
C. What is the main disadvantage of iron?
D. What are the ways to protect iron from rust?
Comparative and Superlative adjectives
Cheap – cheaper – the cheapest
Tough – tougher – the toughest
Costly – more (less) costly – the most (the least) costly
24
7. Compare different materials. Use comparative and superlative
adjectives
A. Mild steel is ___________ ( cheap) than wrought
a. iron.
B. Iron is ____________ (light) than lead.
C. Pure iron is ____________ (soft) than aluminium.
D. Steel may be up to 1000 times ____________ (hard) than pure iron.
E. Iron is ____________ (strong) than lead.
F. Wrought iron is ___________ (corrosion resistant) than steel.
G. Iron is the ____________ widely used of all the metals.
H. Some nickel alloys are among _____________ (tough) structural materials
known.
I. Silver is the _____________ costly of all the precious metals.
Учебный электронный текстовый ресурс
Чистякова Мария Александровна
ENGLISH FOR METALLURGISTS
Учебное пособие по английскому языку для специальных целей
Подготовка к публикации
А.В. Овчинниковой
Разрешено к публикации 08.12.2016
Электронный формат – pdf
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