Translate the sentences from English into Russian. Pay attention to the use of the Participle, the Gerund, the Infinitive Constructions and the Modal Verbs.

1. Of all the elements alloyed with iron carbon is considered to be the most important one for controlling hardness, strength and wear resistance. 2. Steel to be hardened is to be heated to the hardening temperature recommended and held for a sufficient period to allow steel to be fully austenitized. 3. High hardness produced by quenching steel being accompanied by excessive brittleness, the task of the designer is to obtain the desired hardness without losing too much of toughness. 4. To select the proper medium steel should be quenched in to obtain the desired degree of hardness the designer is to remember that steel must be quenched rapidly enough to completely suppress the formation of pearlite. 5. The increase in volume during the transformation of austenite setting up very high stresses, there is always a danger of cracking or warping in water-quenched steel containing over 0,55 per cent carbon. 6. To remove residual stresses the yield stress is to be lowered by raising the temperature to that at which residual stresses are expected to produce plastic flow. 7. Stress relief involving the conversion of elastic to plastic strain, some distortion always accompanies the process. 8. If produced by plastic deformation such as forming, machining and grinding, internal stresses can be removed by an annealing process known as stress relief. 9. A redistribution of stress within a component to be stress-relieve has been found to occur as the surface layers are removed by machining.

9. a) Read the text.

Quenching media

Water is the most common quenching medium used in the hardening of carbon and low alloy steels. In order that the quenching rate be great enough to consistently harden carbon steel the water should be agitated during the quenching operation. Agitation of the cooling medium allows a more uniform and faster cooling action.

A 5-10 per cent sodium chloride brine solution usually gives more rapid and uniform than does straight water (только вода). Brine quenching removes heat from specimens much more rapidly than when a water quench is used.

A 3-5 per cent sodium hydroxide quenching bath has also been found to be good medium for carbon steels. The bath cools even faster than the sodium chloride bath; however, it must be used with caution since sodium hydroxide (caustic soda) may cause burns (ожоги) and may cause blindness (слепота) if splashed into the eyes.

Oil is frequently used as a quenching medium for hardening carbon steels of thin sections such as knives, razor blades, or spring wire. Its quenching rate results in the formation of martensite. Oil is also widely used for quenching heavy sections of alloy and tool steels. Oil is also widely recommended as a quenching medium in preference to water whenever possible because its use results in less danger of cracking, lees distortion, lower residual quenching stresses.

 

b) Choose the correct variant to complete the phrase.

1. In water quenching, water should be agitated

a) to produce greater hardness;

b) to make the quenching operation faster;

 

2. As compared with quenching in straight water, quenching in 5-10 per cent sodium chloride brine-solution can be described as

a) an operation mostly used for heavy sections of alloy stools;

b) more rapid and uniform operation;

 

3. Oil is considered to be a more efficient quenching medium than water because:

a) it decreases cracking and distortion

b) it is used for hardening heavy sections of carbon steels.

 

c) Scan the text “Quenching media” and tell your classmates about:

1. The rate and uniformity of cooling.

2. The field of application.

3. Advantages or disadvantages as compared with other quenching media.

 

Part II

1. Learn the words:

alloying element	легирующий элемент
arrest temperature	температурная остановка
brittleness	хрупкость, ломкость
carbon steel	углеродистая сталь
cast iron	(литейный) чугун
critical point	критическая точка
critical temperature	критическая температура
iron–based alloy	сплав на железной основе
maraging steel	мартенситностареющая сталь
normalized steel	нормальноцементируемая сталь, сталь с нормальной перлитной структурой
precipitation	осаждение, выпадение
spring	пружина
tensile strength	предел прочности, растяжение
transformation temperature	температура перехода, температура фазового структурного изменения
yield strength	предел текучести

 

2. Guess the meaning of the following words:

Technique, period, austenite, finished product, microstructure, elasticity, chromium, effect, carbon steel, concentration, molybdenum, variation.