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MODULE 3. ENGINEERING MATERIALS




 

Exercise 1. Read and guess the meanings of the new words. If you have some difficulties use the dictionary at the end of this book.

1) access. The earliest humans had an access to a very limited number of materials.

2) property. A lot of materials with specialized properties were produced.

3) to encompass. Material science encompasses various classes of materials.

4) alloy. Metallic materials include metals and alloys.

5) ferrous metals. Metallic materials which contain iron are called ferrous metals.

6) non-ferrous metals. Metallic materials which do not contain iron are called non-ferrous metals.

7) cast iron. The most common ferrous metals are cast iron and steel.

8) to influence. Different elements in alloys influence properties of materials.

9) brittleness. Large amount of carbon in cast iron increases its brittleness.

10) to rust. Steel containing nickel or chromium does not rust.

11) tungsten. Steels which contain tungsten or cobalt are extremely hard.

12) copper. Aluminium and copper are widely used.

13) ductile, malleable. Copper is a ductile and malleable metal.

14) frequent. Copper is a frequent element of various metal alloys.

15) brass, tin, lead. Brass contains copper and zinc, bronze contains copper and tin/lead.

16) representative. Polymers are representatives of non-metallic materials.

17) rubber. One of the best known natural polymers is rubber.

18) thermoplastics, thermosets. Plastics can be divided into thermoplastics and thermosets.

19) to mould. Thermoplastics can be heated and moulded numerous times.

20) indispensable. The properties of plastics are indispensable.

21) flexible. Plastics are flexible.

22) relevantly. Plastics are relevantly cheap.

23) subsequent cooling. Ceramic materials are formed by the action of heat and subsequent cooling.

24) clay. Clay was one of the earliest materials used to produce ceramics.

25) stiff. Ceramics tend to be strong, stiff, brittle, and chemically inert.

26) to vary. Ceramics properties vary widely.

27) insulator. Porcelain is widely used to make electrical insulators.

28) available. A lot of engineering materials are available to engineer.

29) to choose. Engineers have to choose the engineering materials.

30) purpose. The engineering materials should be chosen for the given purpose.

 

Exercise 2. Read the international words, mind the stress.

Material, role, civilization, natural, technology, class, traditional, group, metal, polymer, ceramics, nickel, cobalt, aluminium, structure, component, corrosion, thermal, electrical, element, zinc, bronze, polymer, synthetic, plastic, category, industry, product, form, element, reaction.

 

Exercise 3. Read the sentences, point out the Verbals: Infinitive, Gerund, Participle I, Participle II. Give the Russian equivalents. If you have some difficulties use the grammar reference at the end of the book.

1. Metallic materials containing iron are called non-ferrous metals. 2. Clay being one of the earliest materials was used to produce ceramics. 3. The engineers have changed the technological process of producing this material without using this scheme. 4. While describing alloys it is possible to use the term ‘metals’. 5. The engineer has to choose the material best suited to serve the given purpose.

 

Exercise 4. Make up your own sentences with the Verbals according to the models.

Model A: Materials which can be used in this production process are usually

metals.

Materials to be used in this production process are usually metals.

Materials used in this production process are usually metals.

1. Thermoplastics which can be heated numerous times are available of different types. 2. Plastics which can be divided into thermoplastics and thermosets are representatives of non-metallic materials. 3. Civilizations which are named by the level of their material development are the Stone Age, the Bronze Age, and the Iron Age.

Model B: To produce new materials is very important.

Producing new materials is very important.

1. To use the term ‘metals’ is possible. 2. To choose the material for the production process is not easy. 3. To mould thermoplastics is common in the production processes.

Model C: When they were changing the technological process, they chose another

material.

(When) Changing the technological process they chose another material.

1. When you are describing metallic materials, you may use the term ‘metals’. 2. When you are studying the history of civilizations, you get to know that some of them were named by the level of their materials development. 3. When they were making an experiment, they used these data.

Model D: Though the letter was written, it was not sent.

Though written the letter was not sent.

1. Though this alloy is used in the production of this tool, it will not have a wide application in the future. 2. Though cast iron is considered rather brittle, it has a wide application. 3. Though thermosets are moulded only once, they have a wide application.

 

Exercise 5. Read the text, try to focus on its essential facts and choose the most suitable heading given below for each paragraph.

1) Metallic Materials

2) Ceramics

3) Various Classes of Materials

4) Polymers

5) Choosing Materials

 

DIFFERENT KINDS OF ENGINEERING MATERIALS

 

Materials played a major role in the development of societies. Civilizations were named by the level of their materials development, e.g. the Stone Age, the Bronze Age, and the Iron Age. The earliest humans had an access to only a very limited number of natural materials. Modern technologies have made it possible to produce new materials. More than 50,000 materials with specialized properties have been developed by now. Materials science encompasses various classes of materials, but the traditional groups of engineering materials are metallic materials (metals and alloys) and non-metallic materials (polymers, ceramics, etc.).

Metallic materials include ferrous (those that contain iron) and non-ferrous (those that do not contain iron) metals. It should be noted that while describing alloys which are metallic materials it is possible to use the term ‘metals’. The most common ferrous metals are cast iron and steel, which are both alloys. Different elements in alloys influence properties of materials: large amount of carbon in cast iron increases its brittleness; stainless steels containing nickel or chromium do not rust; steels, which contain tungsten or cobalt, are extremely hard, etc. The most widely used non-ferrous metals are aluminium and copper. Aluminium alloys are widely used in engineering structures where light weight or corrosion resistance is required. Copper is a ductile, malleable metal with a very high thermal and electrical conductivity. It is a frequent element of various metal alloys: brass (copper and zinc), bronze (copper and tin/lead).

Polymers are representatives of non-metallic materials. One of the best known natural polymers is rubber. However, most of the polymers used in industry are not natural but synthetic; they are generally called ‘plastics’. Plastics can be divided in two categories: thermoplastics and thermosets. Thermoplastics can be heated and moulded numerous times. Common engineering thermoplastics are ABS (acrylonitrile butadiene styrene); polycarbonate; PVC (polyvinylchloride). Thermosets can be heated and moulded only once, they cannot be remoulded. The most common engineering thermosets are epoxy resins and polyamides. The properties of plastics are indispensable: they are lightweight, hard, easy to shape and colour, flexible, non-rusting, relevantly cheap, etc.

Ceramic materials are inorganic, non-metallic materials which are formed by the action of heat and subsequent cooling. Clay was one of the earliest materials used to produce ceramics, but many different ceramic materials are now being used in domestic and industrial products. Ceramics are strong, stiff, brittle, chemically inert. They are non-conductors of heat and electricity, but still their properties vary widely. For example, porcelain is widely used to make electrical insulators, but some ceramic compounds made from a metal and a non‑metal are superconductors.

Thus, at present a lot of engineering materials are available to engineer, who has to choose the one best suited to serve the given purpose.

 

Exercise 6. Share your vision about engineering materials using the following phrases: in my opinion, if I am not mistaken, as far as I remember, etc.

1. What technologies made it possible to produce new materials?

2. What groups can engineering materials be divided into?

3. What ferrous metals do you know?

4. What non-ferrous metals do you know?

5. What properties of ferrous metals can you name?

6. What are the most important properties of aluminium?

7. Where are aluminium alloys used?

8. What copper alloys do you know?

9. What are the most common representatives of non-metallic materials?

10. What is the difference between thermoplastics and thermosets?

11. Can you name common engineering thermoplastics?

12. Why are the plastics properties indispensable?

13. How are ceramics formed?

14. Are ceramics good conductors of heat and electricity?

15. What should an engineer take into consideration while choosing a material for the given purpose?

 

Exercise 7. Complete logically the following sentences.

1. Materials played …

2. Civilizations were named by …

3. The earliest humans had an access to…

4. Modern technologies have made …

5. Materials science encompasses …

6. The traditional groups of engineering materials are …

7. Metallic materials include …

8. Polymers are …

9. Plastics can be divided into …

10. Ceramics are …

 

Exercise 8. Translate the following sentences from Russian into English. You will have a story on the topic as a pattern.

1. Современные технологии сделали возможным производство новых материалов. 2. К настоящему времени созданы более 50 000 материалов с определенными свойствами. 3. Металлы и неметаллы - традиционные группы конструкционных материалов. 4. Металлические материалы включают черные и цветные металлы. 5. Самые распространенные черные металлы – чугун и сталь. 6. Самые широко используемые цветные металлы – алюминий и медь. 7. Полимеры – представители неметаллических материалов. 8. Синтетические полимеры могут быть разделены на две категории: термопластические и термореактивные пластмассы. 9. Свойства пластмасс незаменимы: они легкие, твердые, нержавеющие, хорошо формуются и красятся. 10. Керамические материалы также являются представителями неметаллических материалов, и их свойства имеют большой диапазон.

 


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