Steel has emerged as one of the 21st century’s most important substances. Widely used in the construction industry, the majority of today’s large, modern structures, including skyscrapers, stadiums, airports and bridges, are supported by a steel skeleton.
Buildings with a concrete structure also use steel for reinforcing, and it’s widely used in the construction of railways, roads, various infrastructure projects and appliances. Everyday life as we know it wouldn’t be the same without steel.
The history of steel production can be traced back almost 4,000 years to the beginning of the Iron Age. Although historians can’t attribute the invention of steel to any one person, they have traced its production history through the ages to discover who is commonly associated with it.
Evolution of steel
The earliest archaeological samples of steel date from around 1800 BC – it has been in use since the days of the Roman Empire, through Chinese dynasties and the Spartans.
In 1300 BC, early blacksmiths were using steel after discovering iron became more durable when carbon was introduced. In 600 BC, Wootz steel was invented in ancient India by craftsmen, who smelted wrought iron with charcoal. Its distinct swirling patterns were much admired, as was the metal’s tough nature. It is still highly regarded today.
In the 3rd century AD, China became the first mass producer of steel, using a technique similar to the Bessemer process, which became popular in Europe many years later, in the 19th century.
In the 4th century AD, the famous Iron Pillar of Delhi was erected. The 23ft-high pillar was constructed to honour the Hindu deity Vishnu. Today, it’s the oldest example of rust-resistant steel still in existence.
Damascus steel was developed in the 11th century in the Middle East and was used mainly for manufacturing sword blades. In the 12th century, Sri Lanka became the largest supplier in the world of crucible steel. Manufactured by a diffusion process, this involves packing wrought iron with charcoal in crucibles or a hearth and heating it to promote the diffusion of carbon into the iron.
In 1702, coke was used for the first time to smelt iron ore. Enabling increased production, it replaced charcoal and wood, which were in short supply. Ten years later, when English inventor Thomas Newcomen built the first commercially viable steam engine, the steel and steam industries led the way for the Industrial Revolution.
During the 18th century, steel became increasingly recognised as a valuable material with a multitude of uses – commonly used for tools, armour and weapons. In 1740, English inventor Benjamin Huntsman further developed the crucible steel technique.
In 1779, production at steel mills was enhanced when they became steam-powered, so they didn’t need to be close to water for the manufacturing process, as they had in the past. The production process improved again in 1783, when English ironmaster Henry Cort invented the steel roller to enhance production techniques.
In the 1830s, America’s agriculture industry increasingly employed steel machinery, particularly for its ability to cut through dense soil. In 1855, the Bessemer process was launched – the first affordable industrial process to mass-produce steel
Produced from molten pig iron, the impurities were removed from the iron by oxidisation, with air being blown through the molten iron – steel became stronger when it was purer. In 1865, the open-hearth process was introduced, burning impurities such as excess carbon out of the pig iron, thus enabling the bulk production of steel.
Following the American Civil War, steel production grew in the 1860s with astounding speed, led by Dunfermline-born industrialist Andrew Carnegie, who moved to America in the 1840s and spearheaded the steel industry’s expansion. He became a multi-millionaire as a result, but gave much of his fortune away to charity. In the 18 years prior to his death in 1919, it was said he gave away some $350 million to worthy causes.
In 1868, Robert Mushet invented Tungsten steel, while in the 1880s, the Brooklyn Bridge became the first steel suspension bridge and the Home Insurance building in Chicago became the first steel skyscraper.
Fast forward to the 20th century, and stainless steel was invented in 1912 by metallurgist Harry Brearley, who was the son of a steelworker from Sheffield. Stainless steel is notable for its resistance to corrosion and has multiple uses – it is ideal for many applications where corrosion-resistance and strength are needed.
Rolled into sheets, bars, plates, tubing and wire, it can be used for cutlery, cookware, major appliances, surgical instruments, road tankers and as a construction material. It is used to manufacture equipment for industries such as chemical plants, paper mills, water treatment plants and storage tanks.
commonly used in food processing plants and commercial kitchens, it can be steam-cleaned and sterilised, with no need for other surface coatings.
Another popular option is carbon steel – a steel that has a carbon content of 3% to 5% of its weight. Although carbon steel dates back to 500 BC, today’s product is much more reliable than its earlier predecessors. It is commonly used for forged steel rings and blind flanges.
The developments first seen in the 1950s and 1960s, when steel was increasingly produced for consumer goods and transport, have continued ever since, with steel becoming ever-more useful in the 21st century.
Biggest steel providers
The world’s largest steel-producing company is Luxembourg-based Arcelor Mittal, which operates in more than 60 countries – it has 232,000 employees and produces one-tenth of the world’s steel, mainly supplying the construction, household, automotive and packaging markets.
The second-largest steel provider is Nippon Steel, based in Tokyo, Japan. With premises in 15 countries, it has almost 83,000 employees and provides steel for the construction, civil engineering, automobile, energy and railway sectors.