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What is steel?
Steel is an alloy of iron and carbon containing less than 2% carbon and 1% manganese and small amounts of silicon, phosphorus, sulphur and oxygen. Steel is the most important engineering and construction material in the world. It is used in every aspect of our lives, from automotive manufacture to construction products, from steel toecaps for protective footwear to refrigerators and washing machines and from cargo ships to the finest scalpel for hospital surgery.
Who invented steel?
A British inventor called Henry Bessemer is generally credited with the invention of steel in 1856. He founded the Bessemer Steel Company in Sheffield, England, but up to 1859 the company made a loss. By the time the patent ran out in 1870 he had made more than 1 million pounds sterling. Steel is still produced using technology based upon the Bessemer Process of blowing air through molten pig iron to oxidise the material and separate impurities.
How is steel made?
Steel is made via two basic routes - from raw materials - iron ore, limestone and coke by the blast furnace and basic oxygen furnace route or from scrap via the electric arc furnace (EAF) method. The raw material approach is known as the integrated route and about 60% of steel produced today is made by this method. The second technique is much easier and faster since it only requires scrap steel. Recycled steel is introduced into a furnace and re-melted along with some other additions to produce the end product. About 34% of steel produced in 2003 was produced via the EAF route.
What is a flat steel product?
A flat steel product is a plate product or a (hot or cold) rolled strip product. Typically steel is rolled between sets of rollers to produce the final thickness. Plate products vary in dimensions from 10 mm to 200 mm and thin flat rolled products from 1 mm to 10 mm. Plate products are used for ship building, construction, large diameter welded pipes and boiler applications. Thin flat products find end use applications in automotive body panels, domestic 'white goods' products, 'tin cans' and whole host of other products from office furniture to heart pacemakers.
What is a long steel product?
A long product is a rod, a bar or a section - typical rod products are the reinforcing rods for concrete, engineering products, gears, tools etc. are typical of bar products and sections are the large rolled steel joists (RSJ) that are used in building construction projects. Wire-drawn products and seamless pipes are also part of the long products group.
What is a mini-mill?
A mini-mill is a molten steel producing process that feeds scrap steel into an electric arc furnace to re-process the material into finished steel for new applications. (See 'How is steel made?' above).
Where is steel produced?
Steel is produced in more than 50 countries worldwide and on every continent except Antarctica.
How much steel is produced worldwide?
In 2007, world crude steel output was 1,343.5 million metric tonnes. This was an increase of 7.6%
on 2006. In 2003, more than 960 million metric tonnes of steel was produced worldwide. The list
outlined below provides the production statistics for a selection of other materials.
- Aluminium: 21.9 million metric tonnes (2002)
- Copper: 14.9 million metric tonnes (2002)
- Gold: 2,600 metric tonnes (2003)
- Portland Cement: 87.8 million metric tons (2000)
- Timber: 300 million m³ (2001)
Figure 1: Crude Steel Production Growth Trend
Which company produces the most steel?
ArcelorMittal Steel produced 117.2 million metric tons (mmt) of crude steel in 2006. Nippon Steel
(34.7 mmt) and JFE (32.0 mmt) were the second and third largest steel-producing companies respectively.
Which country makes the most steel?
In 2006, China produced 422.7 million metric tons (mmt) of crude steel. The top ten steel producing
countries in 2006 were:
- China 422.7 mmt
- Japan 116.2 mmt
- United States 98.6 mmt
- Russia 70.8 mmt
- South Korea 48.5 mmt
- Germany 47.2 mmt
- India 44.0 mmt
- Ukraine 40.9 mmt
- Italy 31.6 mmt
- Brazil 30.9 mmt
In 2003, China produced more than 220 million tons of crude steel making it the first country to exceed
200 million tons of crude steel in a year.
Can you recycle steel?
Of the 960 million tons of steel produced in 2003, more than 60% of it was produced from recycled steel. Steel is the world's most recycled material; indeed one of the two major steel production techniques uses exclusively 100% recycled steel. The additional good news is that the properties of steel remain unchanged no matter how many times the steel is recycled. The steel in your car body might have been a panel from a washing machine in a previous life and even that panel might have been a drink can! In 2001 in North America more than 14.5 millions cars were recycled which is 27 cars per minute! In the United Kingdom 2.5 million refrigerators are replaced annually. In 2002 in South Africa, 64% of all beverage cans were recycled. The country consumes about 3 billion cans annually!
What about environmental protection and sustainability?
Steel is a material, which is very friendly to the environment. This is not only because it is completely recyclable, but also possesses great durability, and compared to other materials, requires relatively low amounts of energy in its production. Innovative lightweight construction, such as in automobile and rail vehicle construction help to save energy and resources, as well. The steel industry has made immense efforts to limit environmental pollution in the last decades. This made it possible to decrease energy consumption and carbon dioxide emissions by one-half of what it was in the 60's, and dust emissions have been reduced by even more! What's more: A wind or solar power plant cannot even exist without steel.
Why does steel rust?
Many elements and materials go through chemical reactions with other elements. When steel comes into contact with water and oxygen there is a chemical reaction and the steel begins to change to its original form - iron oxide. In most modern steel applications this problem is easily overcome by coating. Paint is used in automobiles, enamel is used in refrigerators and other domestic appliances and in other cases elements such as nickel and chromium are added to make stainless steel, which can help prevent rust.
How many different types of steel are available?
Steel is not a single product. There are currently more than 3,500 different grades of steel with many different properties - physical, chemical, environmental, 75% of which have been developed in the last 20 years. If the Eiffel Tower were to be rebuilt today the engineers would only need one-third of the amount of steel, modern cars have new steels with higher strength reducing the overall shell weight by 25%.
from: Worldsteel.org |
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