Read the text and translate two passages in written form

«MECHANICAL PROPERTIES Of MATERIALS»

Materials Science and Technology is the study of ma­terials and how they can be fabricated to meet the needs of modern technology. Using the laboratory techniques and knowledge of physics, chemistry, and metallurgy, scientists are finding new ways of using metals, plastics and other materials.

Engineers must know how materials respond to exter­nal forces, such as tension, compression, torsion, bend­ing, and shear. All materials respond to these forces by elastic deformation. That is, the materials return their original size and form when the external force disap­pears. The materials may also have permanent deforma­tion or they may fracture. The results of external forces are creep and fatigue.

Compression is a pressure causing a decrease in vol­ume. When a material is subjected to a bending, shear­ing, or torsion (twisting) force, both tensile and compressive forces are simultaneously at work. When a metal bar is bent, one side of it is stretched and subjected to a tensional force, and the other side is compressed.

Tension is a pulling force; for example, the force in a cable holding a weight. Under tension, a material usu­ally stretches, returning to its original length if the force does not exceed the material's elastic limit. Under larger tensions, the material does not return completely to its original condition, and under greater forces the mate­rial ruptures.

Fatigue is the growth of cracks under stress. It oc­curs when a mechanical part is subjected to a repeated or cyclic stress, such as vibration. Even when the maximum stress never exceeds the elastic limit, failure of the ma­terial can occur even after a short time. No deformation is seen during fatigue, but small localized cracks develop and propagate through the material until the remain­ing cross-sectional area cannot support the maximum stress of the cyclic force. Knowledge of tensile stress, elastic limits, and the resistance of materials to creep and fatigue are of basic importance in engineering.

Creep is a slow, permanent deformation that results from a steady force acting on a material. Materials at high temperatures usually suffer from this deformation. The gradual loosening of bolts and the deformation of components of machines and engines are all the exam­ples of creep. In many cases the slow deformation stops because deformation eliminates the force causing the creep. Creep extended over a long time finally leads to the rupture of the material.

 

2. Answer the following questions:

1. What are the external forces causing the elastic deformation of materials? Describe those forces that change the form and size of materials.

2. What are the results of external forces?

3. What kinds of deformation are the combinations of tension and compression?

4. What is the result of tension? What happens if the elastic limit of material is exceeded under tension?

5. What do we call fatigue? When does it occur? What are the results of fatigue?

6. What do we call creep? When does this type of per­manent deformation take place? What are the results of creep?

 

3. Translate into English the following sentences:

1. Упругая деформация — это реакция всех мате­риалов на внешние силы, такие, как растяжение, сжа­тие, скручивание, изгиб и срез.

2. Усталость и ползучесть материалов являются результатом внешних сил.

3. Внешние силы вызывают постоянную деформа­цию и разрушение материала.

4. Растягивающие и сжимающие силы работают одновременно, когда мы изгибаем или скручиваем материал.

5. Растяжение материала выше предела его упру­гости дает постоянную деформацию или разрушение.

6. Когда деталь работает долгое время под цикли­ческими напряжениями, в ней появляются небольшие растущие трещины из-за усталости металла.

7. Ползучесть — это медленное изменение размера детали под напряжением.

 

 

4. Find the following in the text:

1. отвечать требованиям современной технологии

2. используя лабораторные методы

3. новые способы использования металлов

4. сжатие, растяжение, изгиб, кручение, срез

5. возвращать первоначальный размер и форму

6. внешняя сила

7. постоянная деформация

8. уменьшение объема

9. растягивающие и сжимающие силы

10. превышать предел упругости материала

11. повторяющиеся циклические напряжения

12. разрушение материала

13. развитие и распространение мелких трещин

14. сопротивление материалов ползучести и устало­сти

 

 

Choose the right variants.  

1. … put my money there if I didn`t think it was safe.

 

A.wouldn`t

B.hadn`t

C.didn`t

D. will

E.would

 

 

2.If I were you, I … to a doctor.

 

A.should go

B.went

C.shall go

D. am going

 E.go

 

3.The vase is beautiful. You … another one to match if you tried.

 

A.wouldn`t find

B.won wouldn`t find `t find

C.wouldn`t have found

D.don`t find

E.hadn`t found

 

 

4.If you … earlier you would have caught the train.

 

A.leave

B.would leave

C.will leave

D.had left

E.left

 

5.If you … the article I recommended, you`d know how to answer such questions.

 

A.read

B.would read

C.had read

D.are reading

E.will read

 

 

6.If the task … easy, I could do it.

 

A.was

B.had been

C.is

D.were

E.would be

 

 

7.They are husband and wife now. If she … so clever and kind, he wouldn`t … her.

A.would be/have married

B.was not/marry

C.were/marry

D.hadn`t been/marry

E.were not/have married

 

 

8.I wouldn`t have a headache now if I … a sleepless night.

 

A.had

B.would have

C.hadn`t had

D.had had

E. were having

 

 

9.Most people who … to Kazakhstan … agree that the Republic is more beautiful in real life

 

A.has been/would

B.have been/would

C.have been/had

D.was/would

E.is/would

 

 

10.I can`t buy it. I haven`t got enough money.

 

A.I will buy it if I will have enough money.

B.If I had had enough money, I would have bought it.

C.I would buy it if I had enough money

D.I would buy it if I have enough money

E.If I had enough money, I`ll buy it.

 

Translate into English using Complex Object

Она хотела, чтобы ее сочинение проверили сейчас же.

Я не хочу, чтобы это платье порвали.

Он не хотел, чтобы ему стригли волосы.

Я хочу, чтобы мой велосипед привезли с дачи.

Я хочу, чтобы этот ковер расстелили на полу в гостиной.

Он не хотел, чтобы трогали его вещи.

Вы хотите, чтобы эту картину повесили над камином?