Vocabulary

Fibre – волокно, нить Fibreglass – стеклопластик Specific strength – удельная

прочность

Reinforced – упрочненный Expansion – расширение Specific stiffness – удельная

жесткость

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The combinations of two or more different materials are called compo-site materials. They usually have unique mechanical and physical properties because they combine the best properties of different materials. For exam-ple, fibre-glass reinforced plastic combines the high strength of thin glass fibres with the ductility and chemical resistance of plastic. Nowadays com-posites are being used for structures such as bridges, boat-building etc.

Composite materials usually consist of synthetic fibres within a matrix, a material that surrounds and is tightly bound to the fibres. The most widely used type of composite materials is polymer matrix composites (PMCs). PMCs consist of fibres made of ceramic materials such as carbon or glass embedded in a plastic matrix. Usually the fibres make up about 60 per cent by volume. Composites with metal matrices or ceramic matrices are called metal matrix composites (MMCs) and ceramic matrix composites (CMCs), respectively.

Continuous-fibre composites are generally required for structural appli-cations. The specific strength (strength-to-density ratio) and specific stiff-ness (elastic modulus-to-density ratio) of continuous carbon fibre PMCs, for example, can be better than metal alloys have. Composites can also have other attractive properties, such as high thermal or electrical conductivity and a low coefficient of thermal expansion.

Although composite materials have certain advantages over conventional materials, composites also have some disadvantages. For example, PMCs and other composite materials tend to be highly anisotropic – that is, their strength, stiffness, and other engineering properties are different depending on the orientation or the composite material. For example, if a PMC is fabricated so that all the fibres are lined up parallel to one another, then the PMC will be very stiff in the perpendicular direction. The designer who uses the composite materials in structures subjected to multidirectional forces, must take these anisotropic properties into account. Also, forming strong connections between separate composite material components is difficult.

The advanced composites have high manufacturing costs. Fabricating composite materials is a complex process. However, new manufacturing techniques are developed. It will become possible to produce composite ma-terials at higher volumes and at a lower cost than is now possible, accelerat-ing the wider exploitation of these materials.

1. What is called composite materials?

2. What are the best properties of fiberglass?

3. What do composite materials usually consist of?

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4. What is used as matrix in composites?

5. What is used as filler or fibers in composites?

6. What are composite materials with ceramic and metal matrices called?

7. What are the advantages of composites?

8. What are the disadvantages of composites?

9. Why should anisotropic properties of composites be taken into ac-count?

Participle I,II

Participle I	Participle II
Verb + ing	Regular verb + ed or V3
Taking	Taken
doing	Done

6. Put the verbs in the correct form.

1 The project _____ (develop) by our specialists is being revised by our director.

2 The woman _____ (speak) now is our new manager.

3 This engine _____ (invent) by our engineers from R&D department is a breakthrough.

4 The scientists_____ (conduct) the research are not able to meet the deadline.

5 New materials ______ (produce) at the plant are very popular with car makers.

6 Some of the questions _____ (put) to the foreman were very impor-tant.

7 The translation _____ (make) yesterday was not correct.

The Participle has two syntactic functions:

	An Attribute	An Adverbial Modifier
Building	The young man building our house with me is my brother. Молодой человек, кото-рый строит дом вместе со мной, мой брат.	He made his living building summer hous-es or garages for people. Он зарабатывал на жизнь, строя людям коттеджи и гаражи.

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Being built Built Having built Having been built

The white stone house being built near the park is a new building of our Art museum. Белокаменное сооруже-ние, строящееся у пар-ка, – новое здание наше-го музея изобразитель-ных искусств. They are reconstructing the house built in the 18th century. Они реставрируют зда-ние, простроенное в XVIII веке. – –

Being built with great skill and care, the man-sion has been used by the family for centu-ries. Так как особняк был построен (будучи простроенным) очень искусно, он служит семье уже несколько веков. If built of the local stone, the road will serve for years. Если построить доро-гу из этого местного камня, она будет служить долгие годы. Having built the house, he began building a green house. Построив дом, он принялся за теплицу. Having been built of concrete, the house was always cold in winter. Так как дом был по-строен из бетона, в нем всегда было холодно зимой.

7. Translate the sentences from Russian into English.

1. He left the office at three o‟clock, saying he would be back at five.

2. Having signed the letter the manager asked the secretary to send it off at once.

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3. Informed of the arrival of the ship, they sent a car to the port.

4. Being checked with great care, the report didn‟t contain any errors.

5. These machines will be sent to the plant being constructed in this re-gion.

6. When writing an essay we must use new words and phrases.

7. The figures mentioned in his article were published in the newspaper. 8. Receiving the telegram, he rang the manager up.

8. Paraphrase the sentences using participles instead of underlined parts.

Model: When he discovered that he had a talent for physics, he gave up his job to enter university.

Discovering that he had a talent for physics, he gave up his job to enter university.

As he had done the task, he left the office. Having done the task, he left the office.

1. When the editor learned that his newspaper had been taken by another publisher, he resigned from his position.

2. I declined his offer of a loan and said that I didn‟t like owing people money.

3. The demonstrator who protested violently was led away by the police. 4. When I visit a strange city, I like to have a guide-book with me.

5. Now that I have heard your side of the question, I am more inclined to agree with you.

6. As he had been warned that bad weather lay ahead, the ship‟s captain changed the course.

9. Write a short (about 200 words) passage about new materials and their properties that you will deal with in your future profession.

UNIT 5. SAFETY AT WORK

Focus: Safety at work.

Grammar focus: The Absolute Participial Construction.

Skills focus: Reading for specific information, enlarging vocabulary with words connected with safety at work and developing listening and speaking skills.

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1. Where would you find the notices below? How do you say these things in your language?

a. Don‟t lean out of the windows. b. Beware of the dog.

c. All visitors must sign up. d. Keep clear.

2. Match the meanings of the signs (1-4) with the shapes (a-d) and co-lours (e-h).

meaning

1. you mustn‟t do this 2. you must do this

3. there is a danger 4. this material

is dangerous

shape a. triangle

b. circle with diagonal line c. square

d. circle

colour

e. yellow and black f. red and white

g. blue and white h orange and black

a b c d e f

g h i j k

3. What do the signs mean? Where would you find them? Match the sentences with the signs?

1. Be careful.

2. Beware of industrial vehicles. 3. Don‟t smoke here.

4. Don‟t walk here. 5. Risk of death.