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3. Fill in the gaps using the text:

  1. Gold, silver and copper were found by…

  2. Iron can be separated from its ores in reasonably… quantities and at fairly … cost.

  3. Metals have comparatively high …with the exception of mercury.

  4. Steel is still the basic material of…

  5. Bronze is used for objects intended to resist …of the atmosphere.

  6. In the ancient times, gold, silver, copper, tin, iron, lead and mercury… as …

  7. From the point of tonnage produced and used …is the world's most common metal

  8. Zinc… in its role as one of the constituents of the alloy brass.

  9. The present age is… and it is important that we should have some acquaintance with these useful substances.

  10. Seven or eight metals …until the eighteenth century.

4. Translate the following words into English:

золото, срібло, мідь, свинець, сталь, цинк, нікель, кобальт, залізо; існувати, знайомство, тепло, латунь, ртуть, ковка, точка плавлення, дорогоцінні матеріали, сплав, речовина (сполука), відокремлювати.

5. Transform sentences from Active to Passive Voice:

Example Romans cremated Julius Caesar’s body 2,000 years ago.

Julius Caesar’s body was cremated 2,000 years ago.

  1. People use steel for producing armaments.

  2. Primitive man found metals free in nature.

  3. If someone mixed tin with copper the resulting substance would be harder.

  4. The Egyptians and Assyrians made some use of iron a number of centuries before our era.

  5. Scientists developed methods for separating iron from its ores in reasonably large quantities and at fairly low cost.

  6. People knew zinc as one of the constituents of the alloy brass.

  7. Analyst can melt metals high melting point temperature.

  8. We call bronze an important material in the scientific and technical progress.

6. Make up Passive tense forms with the following words:

Example: to do

Indefinite

Continuous

Perfect

Present

is done

is being done

have been done

Past

was done

was being done

has been done

Future

will be done

-----------

will have been done

to knew, to change, to use, to increase, to find, to mix, to give, to develop, to separate, to call, to produce.

Part 2. Mechanical Properties

1. Read and translate the following words and words-combinations:

properties, important, strength, elasticity, extension or compression, per unit, permanently, associated, stretching, indentation, toughness, durability, creep, humidity.

2. Read and translate the text.

Mechanical properties are those associated with how a material reacts when subjected to external forces. It is important that you understand the effect of force upon materials. Force will cause material to become stressed. Stress relates to how much load is applied to a given area. Strain is another result of the application of force. This is defined as the amount of distortion (extension or compression) that takes place per unit of length.

Strength is the ability of a material to withstand force without breaking or permanently bending. Figure 1.5 shows how different types of strength resist different types of force.

Elasticity is the ability of a material to bent and flex when subjected to a force and then to return to its previous form when the force is removed. Structures such as bridges and tall building must have a degree of elasticity.

Plasticity is the ability of a material to be changed permanently in shape (deformed) by the application of an external force without breaking or fractures. Most materials become more plastic when heated. The extent to which a material's shape can become changed by hammering, rolling or pressing is called malleability. Another associated term is ductility; this is the ability to undergo cold plastic deformation by bending or stretching. All ductile materials are malleable, but all malleable materials are not necessarily ductile.

Hardness is the ability to resist abrasive wear, indentation and deformation. This is the important property of cutting tools such as turning tools, drills, files and saws.

Toughness is the ability to withstand sudden stress in the form of shocks or blows without fracturing, and also to resist cracking when subjected to bending forces. Repeated bending will cause the toughness of some materials to break down such that they will eventually fracture.

Brittleness is the opposite of toughness. A brittle material will not withstand shocks or bending without fracture.

Durability is the ability to withstand wear, tear and deterioration with time. Durability refers to both the mechanical properties and the appearance of the surface, particularly of metals, is corrosion. Plastic materials are generally less prone to corrosive effects and are therefore durable.

Stability is the ability to resist changes in shape and size over time. Wood is particularly unstable and tends to warp and twist with changes in humidity. Metals and some plastics tend to gradually deform when subjected to stress over long periods; this process is known as creep.