Ferrous metals

In studying engineering processes an engineer who is to build a machine must select suitable materials for each machine member. One must know the characteristics of engineering materials. These are as follows: strength, stiffness, ductility, toughness, elasticity, fatigue resistance, shock resistance, corrosion resistance, wear resistance, hardness resistance, frictional qualities, machinability, casting and forging properties. They depend upon the chemical composition and the physical structure of the material.

From the point of tonnage produced and used, iron is the world's most common metal, fallowed in turn by copper, zinc, lead and aluminium.

Cast iron is a general term applied to iron-carbon alloys containing more than 1.7 per cent of carbon. Cast iron without the addition of alloying elements is weak in tension and shear, strong in compression and has low resistance to impact. It is obtained from the cupola furnace where pig iron is remelted in contact with coke. Grey cast iron has the carbon present in the free or graphite state and is soft, easily machined, and only moderately brittle. White cast iron has most of the carbon in the combined state and is therefore hard and brittle. Malleable cast iron is made by heating white iron castings for a period of several days in airtight pots filled with an oxide of iron.

Steel is a ferrous material with a carbon content from 0.1% to 1,0%. Semisteel is a name to a metal made by melting 20 to 40 p. c. of steel scrap with cast iron in the cupola. Steel castings are more expensive but stronger and tougher.

Wrought iron is quite ductile and can be easily rolled, drawn, forged and welded. It has high resistance to corrosion. The carbon content is generally less than 0.1% and the material must contain not less than 1% slag.

Cast steel normally contains about 0.5% of carbon, and is used to replace cast iron when castings of considerable strength are required. Forged steel is steel that has been hammered, drawn, pressed or rolled in the process of manufacturing of a particular part.

2. Знайти суфіксальні та префіксальні терміни і визначити способи їх перекладу.

3. Скласти міні-словник.

Контрольні питання

1. Що потрібно враховувати для правильного перекладу описів технічних приладів та агрегатів?

2. Які особливості перекладу суфіксальних та префіксальних термінів?

3. Терміни з якими суфіксами передаються транскодуванням?

Література: [8, с. 102-125; 11, с. 46-48].