Metallurgy is a science dealing with the constitution, structure and properties of metals and alloys, and the processes by which they are obtained from ores and adapted for the use of man.
It is based on the laws of physics and chemistry dealing with the fundamentals of matter and energy and the changes which occur in matter.
1. What does the science of metallurgy deal with?
2. What kind of processes does metallurgy concern?
3. What laws is it based on?
4. What do those laws deal with?
Physical metallurgy deals with the correlation between the structures of metals and alloys, as revealed bу the microscope, and their properties, as these properties are affected by the method of manufacture, by heal treatment, chemical composition and hot or cold working of the metals.
1. What does physical metallurgy deal with?
2. How can the structure of a metal be revealed?
3. What affects the properties of a metal?
Extractive metallurgy deals with such operations as mining the ores, concentrating them by some suitable means, and then smelting them to separate the metals.
from the elements with which they are chemically combined. For example, iron ores are first mined, then washed to remove a large part of the earthy impurities with .which they are associated. After this concentration these iron ores (generally oxides) are smelted in a blast furnace, which separates the oxygen from the iron. Pig iron, the product of the blast furnace, then goes to the foundry, or to some steel or wrought iron process at which point we are in the province of physical metallurgy.
What operations does extractive metallurgy deal with?
What is a blast furnace designed for?
What is the product of a blast furnace?
4. Which metallurgy, physical or extractive, does the process of steelmaking belong to?
In order to grasp clearly the subject of metallurgy it is necessary that the fundamentals of physics and chemistry applying to metallurgy be well understood.
Energy may be defined as capacity for doing work, when by work is meant the act of producing a change of the state of matter against a resistance opposing that change.
Heat is one of the best known forms of energy. Its capacity for doing work is utilized in the steam engine, the melting furnace, heat-treating furnace, etc. The quantity of-heat in a given piece is indicated by its temperature and the temperature in turn, is measured with a thermometer (for low temperatures) or with a pyrometer, by means of a thermocouple (for high temperatures).
1. What is energy? What do you mean by work when defining energy?
2. What is heat? Where is its capacity for doing work utilized in metallurgy?
3. What is indicated by temperature? What instrument is it measured with?
Matter is simply defined as that which occupies space. Matter is constantly undergoing changes. These are: (1) physical changes which do not affect the composition of matter, and (2) chemical changes which do affect its composition. The substances taking part in chemical changes are defined as chemical compounds or elements.
Chemical compounds are substances which are homogeneous throughout their masses and which cannot be separated by mechanical means. They are combinations of fundamental substances called "elements".
Elements are those substances which have so far resisted all attempts at further decomposition.
The elements have been given values based on the relative combining weight, using hydrogen as unity, which values are known as atomic weights and which permit the calculations of the weights of reacting substances-and the products formed.
What is matter?
Which changes of matter are called physical and which, chemical?
What are chemical compounds?
What are chemical elements and their atomic weights?
What calculations do the atomic weights permit?
There are two kinds of chemical reactions: exothermic, characterized by the evolution, of heat, and endothermic, by absorption of heat. .
The most important reactions from a metallurgical viewpoint are oxidation and reduction. Oxidation can be; defined as the combination of a substance with oxygen, and reduction as the giving up of oxygen by a substance.
Chemical elements can be classified in two groups according to whether their normal compounds are acid or basic. It is important in metallurgical processes that the acid and basic substances be clearly known. Acids and bases react to form new substances called "salts".
In order to prevent undesired reactions it is necessary in metallurgical processes that acid substances be used; in contact with acid furnaces, that is, silica-lined furnaces; and that basic substances be used in conjunction with basic furnaces, having magnesite or dolomite linings.
What two kinds of chemical reactions do you know?
What is oxidation? Is oxidation an exothermic' or endothermic reaction?
What is reduction?
4. What rule is strictly observed in metallurgical processes to prevent undesired reactions?
IV. Подберите пары синонимов:
A: constitution; to occur; to affect; manufacture; treatment; to apply; to define; to oppose; to indicate; to combine
B: composition;. to associate; to influence; working; to use; to resist; to happen; production; to explain; to show.
V. Подберите пары антонимов:
A: compound; combination; evolution; oxidation; exothermic; to remove; to separate; relative; to melt; to prevent
B: element; to help; absolute; to solidify; endothermic; to combine; absorption; decomposition; reduction; to add.
VI. Переведите словосочетания:
физические свойства металлов и сплавов; получение металла из руд; определить структуру металла при помощи микроскопа; способ производства; горячая и холодная обработка металлов; добывать руды; плавить железные руды в доменной печи; процесс получения сварочного железа; использовать способность теплоты совершать работу; паровой двигатель, плавильные печи и печи для термообработки; измерять высокие температуры с помощью термопары; дать определение материи; занимать пространство; воздействовать на химический состав вещества; вычисление веса реагентов и получение веществ (продуктов); соединение с кислородом; отдача кислорода; предотвратить нежелаемые реакции; футерованные кремнием печи; основные печи, имеющие магнезитовую или доломитовую футеровки.
VII. Подтвердите следующие утверждения, используя предложения из текста.
1. Metallurgy is a science.
2. Heat is one of the best known forms of energy.
3. It is important in metallurgical processes that acid and basic substances be clearly known.
VIII. Задайте вопросы к выделенным словам.
1. Metallurgy is based on the laws of physics and chemistry.
2. Metallurgy deals with the fundamentals of matter and energy.
3. The structures of metals and- alloys are revealed by the microscope.
4. The properties of metals and alloys are affected by very many methods.
5. Iron ores are washed to remove earthy impurities
6. After this concentration the iron ores are smelled in a blast furnace.
7. Energy is defined as capacity for doing work.
8. The quantity of heat in a given piece is indicated its temperature.
9. Matter is undergoing changes.
10. Chemical compounds are homogeneous throughout their masses.