Basic Metallurgy of Cast Iron



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Basic Metallurgy of Cast Iron



The term ‘cast iron’, like the term ‘steel’, identifies a large family of ferrous alloys. Cast irons primarily are alloys of iron that contain more than 2% carbon and form from 1 to 3% silicon. Wide variations in properties can be achieved by varying the balance between carbon and silicon, by alloying with various metallic or nonmetallic elements, and by varying melting, casting and heat treating practices.

Cast irons, as the name implies, are intended to be cast to shape rather than formed in the solid state. Cast irons have low melting temperatures, are very fluid when molten, do not form undesirable surface films when poured, and undergo slight to moderate shrinkage during solidification and cooling. However, cast irons have relatively low impact resistance and ductility, which may limit their use.

Mechanical properties of cast irons - especially strength, ductility, and modulus of elasticity - depend strongly on structure and distribution of microstructural constituents. Physical properties such as thermal conductivity and damping capacity are also strongly influenced by microstructure.

The four basic types of cast iron are white iron, gray iron, ductile iron and malleable iron. White iron and gray iron derive their names from the appearances of their respective fracture surfaces: white iron exhibits a white, crystalline fracture surface, and gray iron exhibits a gray fracture surface with exceedingly tiny facets. Ductile iron derives its name from the fact that, in the as-cast form, it exhibits measurable ductility. By contrast, neither white nor gray iron exhibits significant ductility in a standard tensile test. Malleable iron is cast as white iron, then “malleablized” - that is, heat treated to impart ductility to an otherwise exceedingly brittle material.

Besides the four basic types, there are other specific forms of cast iron to which special names have been applied. Chilled iron is white iron that has been produced by cooling very rapidly through the solidification temperature range. An area of the casting that solidifies at a rate intermediate between those of chilled iron and gray iron, and which exhibits microstructural and fracture-surface features of both types, is known as mottled iron. Compacted graphite cast iron (also known as vermicular iron) has a structure intermediate between those of gray iron and ductile iron.

 

 

Task 1.

Phonetic Exercise

 

Practise after the speaker and learn to pronounce the words given below.

 

identify /ai’dentifai/; constituents /k'n’stitju'nts/; appearance /'‘pi'r'ns/; surface

/’s':fis/; exhibit /ig’zibit/; tensile /’tensail/; malleablized / m'li'‘blaizd/; intermediate / int'‘mi:dj't/; graphite /’grж fait/; vermicular /v':’mikjul'/.

 

 

Task 2.

Lexical Exercises

Exercise 1.Find the English equivalents for the words and word

combinations given below and use them in the

sentences of your own.

 

большое разнообразие свойств; равновесие; литье; в твердом состоянии; отвердение; охлаждение; теплопроводимость; амортизация; белый чугун; серый литейный чугун; растяжение; наделять свойствами; температура отвердения.

 

Exercise 2.Match the English words and word combinations given

below with their Russian equivalents. Use them in the

sentences of your own.

 

1. cast iron 1. закаленный (отбеленный) чугун

2. fluid when molten 2. половинчатый (о чугуне)

3. ductile iron 3. их имя происходит от

4. malleable iron 4. чугун (продукт вторичной плавки)

5. chilled iron 5. жидкий (текучий) в расплавленном

состоянии

6. the solidification temperature 6. их название происходит

7. mottled iron 7. ковкий (тягучий) чугун

8. they derive their names from 8. температура отвердевания

 

Exercise 3.Answer the following questions.

 

1. How can the properties of cast irons be changed? 2. What are the characteristics of cast irons? 3. What do mechanical properties of cast irons depend on? 4. Name the four basic types of cast iron. 5. Are there any other specific forms of cast iron?

 

Exercise 4. More about word-building: Prefixes.

 

In the text given above find the words with prefixes: un-; under-; inter-; im-. Define their meanings if:

un- = not; lack of; do opposite of; release from:

do – undo = не делать

under- = beneath; lower; insufficiently:

developed – underdeveloped = плохо развитый, недоразвитый

inter- = between:

related – interrelated = взаимосвязанный

im- = in, into, against, over:

impregnate = насыщать

Here are the meanings of some words. Fill each blank with the most appropriate word.

undersell - to sell at a lower price

intervene - to come between

underpayment - bad, insufficient payment

immigrate - to move to a foreign country as a permanent resident

interval - a period between two events

1. A lot of Protestants . . . to America, because the Catholic Church was severely following them. 2. Because they buy in larger quantities at lower prices, chain stores are usually able to . . . goods to small shop-owners. 3. During the … the students had their lunch in the university canteen. 4. Because of permanent .. . . she decided to quit the job. 5. The summer vacation . . . between the close of one school year and the beginning of the next.

Exercise 5.Translate at sight

 

Uranium. The heaviest of all elements, a radio-active metal used for nuclear power production.

Cadmium. Used to electro-plate iron for rust protection. Also used for control rods in the atomic reactors of nuclear power stations.

Chromium. Used to give a shiny plating to other metals, and used in alloys of steel to produce stainless steel.

Cobalt. Used in the manufacture of steel cutting-tools. It also produces the blue used in pottery such as the famous ‘Sevres’ products.

Magnesium. Mainly used in the production of strong, light alloys such as duralumin. Also used for photographers flash bulbs. It burns in air with a brilliant, white flame.

 

 

Task 3.

Listening Comprehension

 

Listen to the lecture and answer the following questions

 

1. How many metals are used now?

2. What are the eight most widely used metals?

3. Why can’t other metals be regarded as very important engineering materials?

Task 4.

Focus on Grammar

Participle

Present Participle (I) - ing

Active Passive

Simple giving being given

Perfect having given having been given

 

Past Participle (II) -ed (III form of irregular verbs)

open - opened give - given

 

Past Participle always has a passive meaning.

1. Present Participles can be used as adjectives to describe an action which is still happening.

They watched the burning forest. Они наблюдали за горящим лесом.

На русский язык переводится причастием, деепричастием, определительным или обстоятельственным придаточным предложением.

2. Past Participles can be used as adjectives to describe the result of an action that has happened.

Тhe completed work was given to the teacher. Завершенная работа была передана преподавателю.

Обычно переводится причастием прошедшего времени или страдательным причастием.

3. Participles are often used in participle clauses to describe two actions that happen

a) at the same time: She sat by the fire reading a book.

He went to the party very well dressed.

b) one after another: Opening the bag she took out a purse.

Caught by the boy, the bird tried to fly away.

c) two actions that happen one because of another:

Not knowing what to do I just waited.

4. The subject of a participle need not be the same as the subject of the following verb, but in this case the participle must follow its noun/pronoun. This construction is not connected with the subject of a sentence and has the function of an adverbial modifier:

Theday being fine, we decided to go swimming.

Так как день был прекрасным, мы решили искупаться.

Pure ironranks ninth among the metals in degree of malleability, gold being the most malleable metal known.

По степени ковкости железо занимает девятое место среди металлов, причем золото является самым ковким из известных металлов.

 

Эти обороты называются независимыми причастными оборотами и переводятся на русский язык придаточными предложениями времени, причины, уступительными, условными с соответствующими союзами. Иногда могут переводиться самостоятельными предложениями с сочинительными союзами причем, а, и и т.д. При этом всегда необходимо помнить о контексте и общем смысле высказывания.

Exercise 1.Use simple or perfect forms of Present Participle.

 

1. She was sitting in the arm-chair, (to look) through a newspaper. 2. (To get) a letter from an unknown lady, I decided to invite her for a lunch. 3. (To enter) the room he suddenly saw that there were several unknown people in it. 4. Mother stood (to wave) her hand until we drove away. 5. Every day I see them (to pass) the house. 6. Romeo (to believe) that Julia was dead, decided to kill himself. 7. (To be) there twice, she decided to spend her vacation somewhere else. 8. She entered the hall (to accompany) by her mother. 9. (To warn) she decided not to take the risk and stayed at home. 10. Sam ,(to feel) that the interview was over, stood up.

 

 

Exercise 2.Use the present or past participle.

 

1. They watched the (to burn) forest helplessly. 2. The (to complete) letter was in front of him, but he was (to hesitate) to post it. 3. (To have) a shower, she got dressed. 4. He went to visit his aunt (to dress) as a real gentleman. 5. She gave me a drink (to make) of five different fruits. 6. (To advise) to give up work for a while, he undertook a trip to Europe. 7. During the flight I was (to read) a book. 8. He was (to dress) in a blue cotton shirt and a pair of grey trousers, (to spot) with vegetable oil.

 

 

Exercise 3.In the following pairs of sentences, the same verb is missing

twice, once used as a present participle and once as a past

participle. Insert the verbs in their correct forms.

 

1. I fell on ice, . . . my arm. Three people, . . . in an accident, were taken to hospital. (to hurt)

2. The film, . . . by Stephen Spielberg, is expected to be a great hit. They . . . beautiful silverware in Sheffield. (to make)

3. I looked at her, . . . her youth and beauty. This actress, though . . . by everybody, is very shy and modest. (to admire)

4. He walked down the road, . . . a song. This song is usually . . . by him at the beginning of a concert. (to sing)

5. Books . . . out of the library must be returned within 10 days. . . . a book from the shelf she didn’t notice that it missed several pages. (to take).

Exercise 4.Participle clauses can express the following ideas:

at the same time; because; after; if; with the result that

Which of the above ideas do the following participle clauses express?

 

1. Kissing her mother goodbye, she went off to the station. 2. Knowing how much I liked this book, she presented me with it. 3. Awakened early, he had enough time to pack. 4. Having read the book, I went to bed. 5. Having read the book, I knew all about the subject. 6. He left the house saying he would be back by dinner. 7. Taken in three times a day, this medicine will help you in a week. 8. Having spent all our money in the restaurant, we went home.

Exercice 5. Translate into Russian, paying attention to the use of the participles.

 

1. Alloy is a material consisting of two or more elements. 2. A series of alloys known as aluminium bronzes posess high strength. 3. If worked beyond certain limits, the metal will become very brittle. 4. Depending upon the kind of metal and the final shape desired, one or more rolling operations may be possible. 5. The speed-range depends on the kind of speed-change mechanism used. 6. Engineers of the company designed a press line, believed to be the first of its kind in Britain. 7. Machines and machine products have made possible a standard of living unsurpassed in history. 8. Owing to these methods it has become possible to obtain new mechanical properties of the alloy. 9. The tin strengthens and hardens copper, making it hard and resistant to wear. 10. Iron oxide is the major problem when forging steel. 11. When broken, the material has a black, silken fracture. 12. A piece of steel heated to a bright cherry red and suddenly chilled becomes extremely hard. 13. Manganese, phosphorus, sulphur and silicon are the elements separately and distinctly acting on physical properties of steel. 14. Having found out how to separate the mixture into its components, we understood that we could finish our experiment successfully. 15. Iron and sulphur being ground together, a greenish-black powder is obtained. 16. The atoms in diamond being closer to each other than in graphite, this substance is very hard.

 

Text 2

Pre- reading Task

Read the text given below and find answers to the following questions.

1. What were the first colleges of the US?

2. When was comprehensive education introduced in America?

3. Is the American system of education highly centralized?

4. Who manages secondary and high schools in the US?

5. What is a community college?

6. How long does it take to obtain a bachelor’s degree?

7. Is education free in the US?

8. What do American institutions of higher education include?

 

Education

Over 57 million students are enrolled in American schools, which range from kindergartens to high schools, small colleges, large universities, as well as a variety of institutions for adult education and vocational training. Americans place a high value on education for themselves and their children, and universal access to quality education has been one of the nation’s historic goals.

More than 100 years before the signing of the Declaration of Independence, European settlers in Massachusetts passed laws requiring all communities to hire schoolmasters; larger towns had to establish grammar schools to train children for the university. America’s first college, Harvard, was founded in Massachusetts in 1636, and the second, William and Mary, was established in Virginia in 1693.

Higher education was revolutionized in 1862 by the Morrill Act, which granted federal lands to each state for the creation of agricultural and mechanical colleges. These “land-grant” institutions legitimized vocational and technical education.

By the end of the Civil War in 1865, education was becoming available to all, and educational institutions began to shape a distinctive American culture. In the late 19th and early 20th century, the schools were instrumental in “Americanizing” the massive numbers of immigrants who arrived in the United States. Indeed, the 20th century America is the product of a nationalism defined in large part by its schools.

Perhaps the most noteworthy feature about American education is the absence of a national administration or structure. Each of the 50 states controls and directs its own schools. Most states require that children attend school from the time they reach six or seven years old until they are 16 or 17. Educational requirements are set by the state legislatures, and public schools are managed by local communities, divided into about 15,500 state school districts.

About 85 percent of American students attend public schools which are supported by state and local taxes. The other 15 percent attend private schools, for which their families choose to pay special attendance fees. Four out of five American private schools are run by churches, synagogues or other religious groups.

In addition, schools have for many years received federal aid for special purposes, such as vocational training and school lunches. In 1965 Congress approved a major program of federal support for public schools, and federal aid was extended to private schools for the first time.

After graduating from secondary school, a growing number of Americans go on to higher education. The percentage of high school graduates enrolling in public colleges, for instance, has increased from 40.4 percent in 1960 to 54.3 percent in 1984. American institutions of higher education include technical training schools, which offer programs in fields ranging from hairstyling to computer programming; community colleges, which provide two years of semiprofessional training for some students and the first two years of college for others; colleges, offering four-year bachelor degree programs; and universities, which contain one or more colleges and graduate schools offering master’s or doctoral degree programs. The factors determining an institution’s prestige are the quality of the teaching faculty; quality of research facilities; amount of funding available; and the competence and number of applicants for admission.

 

 

Task 2.

Comprehension Check

Exercise 1.Here are the answers to some questions about the text.

Make up the questions.

 

1. Americans place a high value on education for themselves and their children.

2. By the end of the Civil War in 1865 education was becoming available for all.

3. American education is not highly centralized.

4. Each of the states controls and directs its own schools.

5. Schools have for many years received federal aid for vocational training.

6. American institutions of higher education include technical training schools, community colleges; colleges offering four-year bachelor degree programs and universities.

7. The factors determining an institution’s prestige are the quality of teaching, research facilities, amount of funding available.

8. Four out of five American private schools and universities are run by religious institutions.

 

Exercise 2.Complete the statements by choosing the right variant.

 

1. Students in Russian institutions of higher education . . . on the basis of entrance examinations.

a) are accepted b) enter c) are enrolled

2. Secondary education in the US has been . . . for all since the end of the Civil War.

a) available b) possible c) difficult

3. American education is characterized by the . . . of a centralized structure.

a) presence b) absence c) establishment

4. The state . . . set all educational requirements.

a) authorities b) administration c) legislatures

5. Schools receive federal . . . for special purposes.

a) aid b) assistance c) help

6. Americans . . . a high value on education.

a) put b) give c) place

7. Most American states . . . that children start schooling at the age of 6.

a) demand b) require c) insist

8. Public schools are supported by state and . . . taxes.

a) federal b) local c) private

9. Only . . . can offer doctoral degree programs.

a) universities b) community colleges c) vocational colleges

 

Exercise 3. What makes a good teacher?

Look at the following ideas and say which ones are

important in your opinion.

A good teacher:

- knows his/her subject very well

- gives interesting lessons

- makes sure the classroom is tidy and attractive

- always prepares his/her lessons

Now work with a partner to add at least four more characteristics of a good teacher.

Exercise 4.Find the Russian equivalents to the following proverbs.

Enlarge on them.

Better unborn than untaught.

Better untaught then ill-taught.

Learn wisdom by the follies of others.

Learn to say before you sing.

 

It is interesting to know that . . .

At an American college a freshman is a first-year student; a sophomore is a second-year student; a senior is a fourth-year student. All students who graduate from the senior course and who continue studying at a university are graduate students. Some graduate students who receive scholarships are called university fellows. The fellow assists a professor in a special field of research or takes responsibility for some classroom instruction.

 

 

Oral Practice

Business Correspondence: a Letter of Application

A Job Interview

 

The letter of application is also called the covering letter and it is as important as CV. They both provide the first direct contact between a candidate and an employer. If it is not written properly, it can produce a bad impression. Usually it contains 3 or more paragraphs in which you should:

 

- confirm that you wish to apply and say where you learned about the job;

- say why you are interested in the position and relate your interests to those

of the company;

- show that you can contribute to the job by highlighting your most relevant

skills and experience;

- indicate your willingness to attend an interview (and possibly state when

you would be free to attend).

 

The opening line will be:

“Dear Sir” (addressed to a man); “Dear Madam” (addressed to a woman);

“Dear Sir or Madam” (if you don’t know who you are addressing to)

or just “Dear Mr Brown”/ “Dear Ms Smith”

Here is a sample of such a letter:

Natalie Smith

11 Blackpool Str.

Alfa Ltd

Kent

 

Dear Ms Smith,

I’m writing to you to apply for the position of Public Affairs Associate advertised in the International Herald Tribune last week.

Although I’m presently working for National Trust Fund, it has always been my intention to work in commercial environment. I would particularly enjoy the chance to work for your company and as you will notice on my enclosed curriculum vitae, the job you are offering matches my professional interests.

My work experience has familiarised me with the challenges involved in public relations today. I am sure that this together with my fluent knowledge of French would be extremely relevant to the position.

I would be pleased to discuss my curriculum vitae with you in more detail at an interview. In the meantime do not hesitate to contact me if you require further information.

I look forward to hearing from you.

Yours sincerely

Particia Flynch

11 High Street

Ramsgate EH 2 2LM

Kent

14.08.2000

Exercise 1.Write letters of application for the following positions:

1. Accountant: up too 35, degree in Finance/Economics; spoken English

Knowledge of GAAP accounting , software (is a plus)

Preparing accounting documentation & reporting to

Chief Accountant. Preparing documents for tax authorities,

salary calculation.

Contact with the banks for operations and follow up.

Salary up to $500.

 

2. Chief of Department of Bank Currency Operations:

30 - 40; university degree in Finance; fluent English;

over 3 years experience in currency operations and

international payments. Salary $1000 + bonus.

Tel: 978 - 6842

tel/fax: 978 - 8092

Exercise 2. A Job Interview

 

Ms Flynch: May I come in?

Mr Smith: Yes, please. You must be Ms Flynch. I’ve got your CV and letter

of application. What’s your background?

Ms Flynch: I’ve got an engineering degree from Imperial College and a

Diploma in Public Relations from London Chamber of

Commerce. Three-year experience with Sheffield silver-works

and two year experience in public relations.

Mr Smith: That’s fine. But you’ve got an excellent job. Why do you want to

change it?

Ms Flynch: Commercial work attracts me more. It is active and imaginative

imaginative. Besides I’m commuting to my present job.

Mr Smith: I see. Do you have any references?

Ms Flynch: Yes, I do.

Mr Smith: Fine. We’ll let you know about the results in two weeks.

Ms Flynch: And will this job include any perks? Are there chances for

promotion?

Mr Smith: Yes, you’ll have a car. The starting salary is 250 pounds a week.

 

Exercise 3.Make a dialogue of your own. A student-interviewer fills

in the interview report form

Interview Report Form

1. Job title ___________________________________________

2. Name of applicant __________________________________

3. Address ___________________________________________

 permanent accomodation  temporary accomodation

4. Age  under 20  20 - 24  25 - 30  over 30

5. Educational qualifications _____________________________

details of subjects

6. Foreign languages spoken

_______ Fluent Very good Good Fair

_______    

_______

_______

7. Work experience

industrial commercial retail

casual labour voluntary other

details _________________________-

8. General health and fitness:

excellent good fair poor

9. Hobbies

sport music theatre/cinema handicrafts

other

10. Personality

shy/nervous cold/distant relaxed/friendly

too casual/informal overconfident

11. Details of availability ____________________________

12. Starting salary offered ___________________________

 

Unit 3

Text 1

Alloy Steels

Alloy steels play an important role in all fields of industry. They are produced by the introduction of certain non-ferrous metals into low-carbon steels, notably tungsten, manganese, nickel and chromium.

One of the earliest alloy steels was introduced by R.F.Mushet who by adding tungsten to steel discovered self-hardening steel in 1868. Tools made by this method revolutionized machining processes, and it was also upon Mushet’s self-hardening steel that the experiments were based, which led to the production of the high-speed steels developed later in America.

In 1893 Robert Hadfield made an important step forward in this field by incorporating manganese in steel. This alloy was found to possess remarkable tensile strength, elongation and hardness, and became invaluable for all machinery and plant subject to abrasive action such as railway crossings, dredger buckets and the like. These types of steel, however, did not provide a steel suitable for general constructional purposes, a start in this direction being made by J.Riley of Glasgow, who in 1889 by small additions of nickel to steel markedly increased the strength and toughness without decreasing the ductility. By addition of a further alloying element, chromium, H. Brearley in 1913 founded a class of constructional steels which, in addition to strength and resistance to wear, were also resistant to corrosion.

These alloy steels heralded in the Alloy Steel Age, and so great was their development that at the outbreak of the 1939 war there were no less than 2,000 different specifications dealing solely with alloys having various proportions of nickel, chromium and small additions of other elements. With such developments as jet propulsion, nuclear fusion as a source of power and space technology, the acceleration in alloys is likely to continue.

 

Task 1.

Phonetic Exercise

Practise after the speaker and learn to pronounce the words given below:

manganese /m'ng'‘ni:z/; tungsten /’t/\ ngst'n/; chromium /’kromj'm/; revolutionize /rev'‘lu:ò'niz/; incorporate /in’ko:p'reit/; tensile /’tensail/; elongation /i:l'n’geiò'n/; abrasive / '‘breisiv/.

 

 

Task 2.

Lexical Exercises

Exercise 1.Find the English equivalents for the words and word- combinations

given below and use them in the sentences of your own.

of your own.

 

во всех отраслях промышленности; сталь с низким содержанием углерода; вольфрам; хром; марганец; революционизировать процесс обработки; растяжимость; значительно повысить твердость стали; конструкционная (строительная) сталь; возвестить; реактивное движение; слияние ядер.

 

Exercise 2. Match the English words and word combinations given

below with their Russian equivalents. Use them in the

sentences of your own.

 

1. self-hardening steel 1. предел прочности при растяжении

2. high-speed steel 2. испытывающее действие трения

3. railway crossings 3. и тому подобное

4. tensile strength 4. накануне

5. the like 5. ускорение развития сплавов

6. subject to abrasive action 6. иметь дело исключительно с

7. at the outbreak of 7. дальнейшая разработка сплавов

8. dealing solely with 8. быстрорежущая сталь

9. the acceleration in alloys 9. дисперсно-твердеющая сталь

Exercise 3.Answer the following questions.

 

1. What is the way of producing alloy steels?

2. Why was incorporating manganese in steel an important step forward?

3. Which alloy steels are good for constructional purposes?

4. Why is the acceleration in alloys likely to continue?

 

Exercise 4.Look through the text and find the words which mean

the same as:

 

a branch of industry to change completely to unite closely

appropriate to concern with exclusively

to go on

 

Exercise 5. More about word-building: Prefixes.

e-, ex- = out, from, away

emigrate = move out of the country = эмигрировать

eminent = standing out, distinguished = выдающийся

expel = drive out = исключить

 

ante- = before ; post- = after; semi- = half

anteroom = a room forming an entrance to another = прихожая, приемная

postgraduate = a person who continues studying after graduation from a university = аспирант

semicircle = half of a circle = полукруг

 

Translate at sight:

1. Workers were paid on a semimonthly basis. 2. He has missed so many lectures, I am afraid he will be expelled from the university. 3. Workers who enter a semiskilled occupation do not have to undergo a long period of training. 4. My antecedents settled in London about a century ago. 5. After college Peter hopes to do postgraduate research in Department of Materials Science. 6. Iron is extracted from a rocky material called iron ore. 7. At the end of the lesson a group gathered around the teacher in a semicircle to ask additional questions. 8. You will not have to add a postscript if you plan your letter carefully.

 

Exercise 5. Give a written Russian translation of the following passages

 

1.There are carbon steels and alloy steels. Low-carbon steels are tough, yet easy to shape. High-carbon steels are hard and brittle, but can be given sharp cutting edges. Alloy steels contain a range of metals, each giving the steel a special property. Chromium, nickel, and steel make stainless steel, which is hard-wearing and does not rust.

 

2. Steel can be shaped in a variety of ways. Rolling stretches and squeezes ingots of steel into sheets, tubes, or strips. In drawing, rolled steel is pulled through a hole to make a wire. In casting, it is left to cool in a mould. Forged steel is made by squeezing hot steel.

 

3. Most iron is converted into steel in a basic oxygen furnace. A mixture of iron and steel scrap is poured into the furnace, and a jet of oxygen is blown over it. Oxygen combines with the carbon in the iron, carrying it away as carbon monoxide. It takes a basic oxygen furnace just 40 minutes to produce 350 tonnes of steel.

4. The ladles of molten steel are poured into moulds to make ingots, or a reservoir that serves a continuous casting process. Most steel is continuously cast because it is cheaper and better quality. These blocks of steel, called billets, can then be shaped by rolling, forging or casting.

 

Exercise 6.Listen to the short lecture and answer the following questions.

 

1. What is the main difference between ferrous and non-ferrous metals?

2. What are the properties of all metals.

3. Why is cast iron chiefly used in building?

4. What is a steel frame used for?

 

 

Task 3.

Focus on Grammar

Gerund

The Gerund has exactly the same form as the present participle:

running; speaking; etc.

The perfect Gerund - having run; having spoken

The passive Gerund - being written; having been written

It can be used:

1) as subject of a sentence

Developing a new method has taken much time.

Разработка нового метода потребовала много времени.

2) after prepositions:

He is thinking of going abroad this year.

Он думает о том, чтобы поехать за границу в этом году.

She is fond of skating. Она любит кататься на коньках.

3) after certain verbs: admit, anticipate, appreciate, avoid, consider, delay, deny, dislike, enjoy, escape, excuse, fancy, finish, forgive, imagine, keep (continue), mind (object), miss, postpone, prevent, remember (recollect), resist, stop, suggest, understand.

Forgive my interrupting you. I can’t prevent his (him) going there.

Извините, что я прерываю вас. Я не могу помешать ему идти туда.

He disliked working late. Do you mind my (me) taking this book?

Он не любит работать допоздна. Вы не возражаете, если я возьму эту

книгу?

4) The perfect gerund is used when we are referring to a past action:

He denied having been there. Он отрицал, что был там.

5) A number of verbs and prepositions can be followed by posessive adjective/pronoun / noun object + gerund

I insist on his writing a letter immediately. I heard about your brother’s going

Я настаиваю на том, чтобы он немедлен- abroad. Я слышал, что ваш брат

но написал письмо. едет за границу.

In less formal English we may not use the possessive case with the gerund:

Forgive me ringing you up so early. I don’t remember my brother waking up

Извини, что звоню тебе так рано.so early. Я не помню, чтобы мой брат

так рано вставал.



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