1 Sum up the information of the text, complete the table:

Materials		Advantages		Drawbacks
in English	in Russian	in English	in Russian	in English	in Russian
Low carbon steel Medium carbon steel High carbon steel Copper Tin Zinc Lead Nickel Gold Aluminium

2 Complete the sentence according to the text.

Ferrous alloys are specified for more engineering applications than all non-ferrous metals combined …

a) as they have a variety of preferable properties and a low cost.

b) as they are strong, stiff and stainless.

c) because the amount of carbon influences its properties considerably.

BUSINESS ACTIVITY

Complete the dialogue:

A: “Excuse me. Can I see John Marshall?”

B: “_____________”.

I’m afraid, Mr. Marshall is out.

We don’t have such people.

Who’s asking?

What?

Unit 3 casting text 1 Engineering Castings

Iron is a common element in the earth's crust, but it almost always occurs as a compound: it is very rare to find it naturally as metallic iron. It's not known when human beings first discovered how to smelt iron ore to produce useable iron. The oldest-known iron objects, found at two sites on the banks of the Nile, are beads made of iron derived from meteorites, which date from around 6,000 years ago. "Meteoric iron" was widely known throughout the ancient world, where it was cold-worked (if it didn't break in the process) to produce spear tips and ornaments. The Egyptians even called this material the 'metal of heaven' because of its association with meteorites.

The History of Castings

This association with the heavens also probably gave rise to the stories of sword-smiths and the weapons they produced having mystical properties. Initially this iron was an extremely expensive metal to produce, indeed when King Tutankhamen died, about 1400 BC, he was buried with one of the most lavish funerals of all time. When it was discovered in 1922, the tomb contained more gold than the Royal Bank of Egypt at the time. Tutankhamen had with him a truly royal weapon: an iron dagger with a hilt and sheath of gold decorated with rock crystal.

The Iron Age in Britain covered the period from about 700 BC to 43 AD following the Bronze Age and before the Roman period when the working and use of iron gradually spread throughout Britain. The use of iron was to a large extent limited to prestigious or ritual objects for much of this period. Only in the later Iron Age did iron become relatively commonplace in everyday use. The earliest iron objects were swords, with other weapons, engineering castings and tools following afterwards. Technological innovation gathered pace and during the latter part of the period saw the introduction of the potter's wheel, the simple lathe and iron-tipped ploughs. The demand for cast iron engineering castings increased dramatically during the industrial revolution as production methods were refined and the quality of cast iron became more reliable.

Increasing Uses of Engineering Castings

The understanding of how iron could be refined and how the finished poured metal could be controlled using varying levels of carbon, silicon and temperatures lead to more and more uses being found for it in the engineering castings sector. Further refinement of techniques helped cast iron to replace some of the traditional forged steel engineering castings, since it was, by now, cheaper to produce and easier to work with. It was against this backdrop that Coupe Foundry was founded, with the primary object of producing cast iron engineering castings. Architectural castings, agricultural castings, ornamental castings and decorative castings were added to the company's portfolio soon after the company formed.

The 1914-1918 war years lead to a further increase in demand for engineering castings for machinery to produce weapons and ammunition. One of the benefits of using cast iron in engineering castings is that the carbon in the solidified iron acts in a similar way to a lubricant, this makes it ideal for applications such as machine tables and slides. Further expansion of the engineering cast iron foundry industry took place during the Second World War when demand increased dramatically for engine blocks and associated engineering castings.

In 1943 at the International Nickel Company Research Laboratory, Keith Dwight Millis made a ladle addition of magnesium (as a copper-magnesium alloy) to cast iron. The solidified castings contained not graphite flakes, but nearly perfect spheres of graphite. Ductile iron or e.g. iron as it is more commonly known, was born! The term S.G. derives from the full name, Spheroidal Graphite, which in turn describes in simplistic terms the difference between the irons, in that the flakes of carbon traces in cast iron are transformed into spheres or globules in S.G. The late 1950's and early 1960's saw the development of S.G. (ductile) irons which gave a large increase in tensile strengths and elongation.

The Development of Engineering Castings

These new grades of iron, the higher grades of which could be flame hardened to increase working life, lead designers to specify it in engineering castings instead of the traditional steel grades which were more expensive to produce. The development of these new grades of S.G. (ductile) irons also coincided with the increasing popularity of the polystyrene, (or full mould) moulding technique, which encouraged the production of more complex engineering castings and automotive press dies. More recently irons with high nickel and/or chrome content, together with highly specialised irons such as high silicon and compacted irons have been added to the range to enable cast iron engineering castings to compete with traditional steel casting applications.