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Unit 2
Ferrous –Metals

1. 
   Language
   

Ex. 1. Remember the following words and word combinations:

machine-building industr y engineering metal ferrous metal non-ferrous metal tool – steel iron cast iron grey iron alloy cast iron malleable iron casting foundry mould shop alloy part content carbon silicon phosphorus manganese sulphur to reduce to solidify to confine to machine to anneal to pour bed plate wheel grade strength shrinkage brittle on account of

машинобудування технічний метал чорний метал кольоровий метал інструментальна сталь залізо чавун сірий чавун легірований чавун ковкий чавун відливка, виливання ливарний завод ливарна форма цех сплав, сплавляти деталь зміст вуглець кремній фосфор марганець сірка зменшувати затвердіти обмежувати піддавати мех. обробці випалювати, відпускати виливати підпорна плита колесо якість, сорт сила, міцність стиснення, всідання крихкий, ламкий через, як наслідок

машиностроение технический метал черный метал цветной метал инструментальная сталь железо чугун серый чугун легированный чугун ковкий чугун отливка, литье литейный завод литейная форма цех сплав, плавить деталь содержание углерод кремний фосфор марганец сера уменьшать затвердевать ограничивать подвергать мех.обработке отжигать, отпускать лить, отливать опорная плита колесо качество, сорт сила, прочность сжатие, усушка, усадка хрупкий, ломкий из-за вследствие

Ex. 2. Read the following international words and guess their meaning.
Process, airplane, type, machinery, limit, percentage, numerous, to adapt, variety, hydraulic, cylinder, agriculture, proportion, manufacture, object, nature, shock, state.


Ex. 3 Translate these words into English:
природа, виробництво, предмет, поштовх ( струс), стан, багато численний, межа, тип, різноманітність.


Ex. 4 Put these words according to the alphabet and translate:
Strong, brittle, present, melt, hard, rapidly, weak, future, difficult, solidify, easy, slowly, casting.


ІІ. Reading


Ex.5. Read and translate the text “Ferrous metals”.


Text A
Ferrous metals
Different metals are widely used in the machine-building industry. Metals applied for industrial purposes are called “engineering metals”. There are two groups of metals: ferrous metals and non-ferrous metals.
Ferrous metals consist of iron combined with carbon, silicon, phosphorus and other elements. Carbon is the most important of all elements present in ferrous alloys. Ferrous metals are used in industry in two general forms; steel and cast iron, which differ in the quantity of carbon content. Metals are usually melted and poured into a form which is called a “mould”. This process is known as casting. The cast metal is shaped in the mould where it cools and solidifies. Thus one can cast different objects known as castings. The shop where metals are cast is called a “foundry”. Steel is iron with a very little carbon content (from 0.05 to 1.7 per cent) which makes it much stronger than iron and is therefore widely used in machine – building. But very much carbon content makes steel brittle, which reduces its strength. Therefore the carbon content in steel is confined to certain limits.
Cast iron contains a higher percentage of carbon than steel does. Grey iron foundries are the most numerous, because grey iron can be cast into any shape and size. Grey iron is also adapted to a great variety of castings, such as automobile, gas, steam, and hydraulic engine cylinder, bed plates for machines, car wheels and so on. Grey iron castings can be made so hard that ordinary tool steel will not cut them or, on the other hand, so soft that they can be readily machined. However, in comparison with other casting metals grey iron is weak and will not stand great shock. The alloy of grey castings is composed of iron, carbon, silicon, phosphorus, manganese, and sulphur. These elements are used in different proportions depending on the grade of castings.
Alloy grey iron is one of the latest alloys developed and has a promising future. Malleable iron castings are being increasingly used every year in the manufacture of machinery. Malleable iron castings are being increasingly used every year in the manufacture of machinery. Malleable iron can be cast into very large bodies on account of its shrinkage and because of the difficulty on annealing. It is the most easily machined of all ferrous alloys. It has to be melted very hot and poured very rapidly, because it solidifies quickly. Malleable iron castings are used in agriculture machinery, railroad equipment, automobile parts and many other products.