Unit three engineering materials

Text 1 Metals

Просмотрите текст и выполните следующие задания.

I. Используя специализированный англо-русский словарь по технологии машиностроения и металлообработке, переведите следующие слова и словосочетания и запомните их:

strength

toughness

steel

alloy (v., n.)

to mix

to work

to machine

machining resistance

to treat, treatment

corrosion resistant

hardening (n.)

tempering (n.)

annealing (n.)

II. Переведите следующие именные группы, обращая внимание на перевод слов в функции определения:

metal object; aluminium bronze; wear resistance; heat treatment

III. Укажите способ словообразования следующих слов и переведите их на русский язык:

generally, appearance, toughness, resistant, resistance, requirement, specification, harden

IV. Назовите приставки в следующих словах. Переведите слова на русский язык:

non-metal, non-conductor, recycle, reuse, mismachined, misadjustment, pretreatment, preload

V. Найдите в первом абзаце предложение, в котором глагол "to have" является модальным, и переведите его на русский язык.

VI. Найдите в первом абзаце предложения с конструкцией "There + be" и переведите их.

VII. Выпишите из третьего абзаца предложение с местоимением "it", определите его функцию и переведите вместе с относящимися к нему словами.

VIII. Выпишите из текста все сказуемые в страдательном залоге, в составе которых есть модальный глагол "can", и переведите их вместе с относящимися к ним подлежащими.

IX. Выпишите из второго абзацаинфинитив в функции определения и переведите его вместе с определяемым существительным.

X. Найдите в четвертом абзацеинфинитивы, определите их функции и переведите вместе с относящимися к ним словами.

XI. Переведите следующие предложения, обращая внимание наинфинитив:

a. 1. Machining resistance of metals depends upon other substances to be present in them.

2. Engineering metals to be discussed have wide industrial applications.

3. It is to be noted that the metals to be used in the experiment must be corrosion resistant.

b. 1. Some metals have to be melted at very high temperatures.

2. Very few objects are made of pure tin, but it is used to make bronze.

3. Copper and aluminium are often mixed together to form an alloy called aluminium bronze.

4. Annealing had to be carried out to make the metal softer.

XII. Переведите текст с учетом выполненных заданий. Первый и второй абзацы переведите письменно.

1. Engineers have to know the best and most economical materials to use. Engineers must also understand the properties of these materials and how they can be worked. There are two kinds of materials used in engineering — metals and non-metals. Why does man use metals still so much today when there are other materials especially plastics? A material is generally used because it offers the required strength and other properties at minimum cost. Appearance is also an important factor. The main advantage of metals is their strength and toughness. Concrete may be cheaper and is often used in building, but even concrete depends on its core of steel for strength.

2. Plastics are lighter and more corrosion-resistant, but they are not usually as strong. Another problem with plastics to be solved is what to do with them after use. Metal objects can often be broken down and the metals recycled; plastics can only be dumped or burned.

3. It is to be noted that not all metals are strong, however. Copper and aluminium, for example, are both fairly weak — but if they are mixed together, the result is an alloy called aluminium bronze which is much stronger than either pure copper or pure aluminium. Alloying is an important method of obtaining whatever special properties are required: strength, toughness, wear resistance, magnetic properties, machining resistance, etc.

4. The properties of a metal can be further improved by use of heat treatment, hardening, tempering, annealing, etc. For example, hardening is used to make metals harder. Tempering makes them softer and less brittle. Annealing is carried out to make a metal soft so that it can be machined more easily. In this way, metallic materials can be produced to meet every kind of engineering specification and requirement.