STEEL PROFESSIONAL ENGLISH IN USE FOR ENGINEERING

 

PROFESSIONAL ENGLISH IN USE FOR ENGINEERING UNIT 12. STEEL

 

A Carbon steels This extract from an article in an engineering journal is about different types of steel. B Alloy steels The article goes on to look at alloy steels. The second main category of steel is alloy steels, which consist of iron, carbon and one or more alloying metals. Specific grades of alloy steel include: ·         Low alloy steels, which contain 90% or more iron, and up to approximately 10% of alloying metals such as chromium, nickel, manganese, molybdenum and vanadium. ·         High strength low alloy steels (HSLA), which contain smaller quantities of the above metals (typically less than 2%). C Corrosion One weakness of mild steel is that it corrodes – its surface progressively deteriorates due to a chemical reaction. This reaction takes place between the iron in the steel and the oxygen (O2) in the air, to form iron oxide. When     EXERCISES 12.1 Decide whether the sentences below are true or false, and correct the false sentences. Look at A and B opposite to help you. 1. Steel is an alloy of iron and carbon. 2. Mild steel is a high carbon steel. 3. Alloy steels contain carbon. 12.2 Complete the table with words related to corrode, oxide and rust. Then use the words to complete the sentences below. There is more than one possible answer. Look at C opposite to help you. 1. When steel is exposed to air and water, it ____________. 12.3 Complete the article about a special type of steel, using words from A, B and C opposite. Weathering steel The perennial problem with mild (1)_________ is that it (2)_________ when exposed to air and water. Generally the only solution is either to apply a protective coating, or to use another (3)_________ of steel that is resistant to the (4)_________ process – the most well-known being (5)_________ steel, which contains significant quantities of (6)_________ and, often, nickel.

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