The secrets behind Wootz steel

Iron ore has been part of steel making for thousands of years, but questions remain about how ancient civilisations managed to make steel of such exceptional grades and qualities, such as Wootz steel, Damascus steel and Crucible steel, considering their basic tools. But as modern metallurgy continues to advance, we’re discovering more about the methods and materials the first steelmakers used and learning that their techniques were far from primitive.

What is Wootz steel?

While it might make a great brand name, Wootz Steel is probably a mispronunciation or poor translation of the word ‘utsa’ – a Sanskrit word for fountain or ukku/uruku – the word for steel in the Indian language of Kannada and old Tamil respectively. Wootz steel refers to an ultra-high grade of carbon steel, containing between 1-2% carbon. It is Wootz steel that is thought to be behind the famed Damascus blades.

Originating from India and Sri Lanka, excavations have shown that Wootz steel was being made as early as 300BC and was fabricated using the crucible process. A crucible is a container that can be used in very hot temperatures. For a crucible to be used to melt steel, it needs to get to a temperature of between 1300-1400 degrees centigrade. In 300BC, the crucible used for making Wootz steel would have been made of clay. It’s now widely recognised that the crucible steel was being produced across large parts of India, Pakistan and Sri Lanka. Crucible steel is the term given to any steel produced using this method.

How was it made?

It was during the early European expeditions to the sub-continent in the 1800s when detailed descriptions were recorded about how Wootz steel was made, as Europeans attempted to understand how such high quality steel could have been produced during ancient times using the crucible method of steel making.

Following a number of attempts using the same method back in England but failing to get the same result, scientists discovered that it was the carbon content of the steel that contributed to its extraordinary strength more than the method of steel making. Wootz steel continued to be studied right up until the 1900s but it wasn’t until the 20th century that another unique quality of Wootz steel revealed itself.

Why is it relevant today?

In studying the properties of Wootz steel, the superplasticity quality of high carbon steel was discovered. Steel with a carbon content of 1.2-2% can be superplastic. Superplasticity occurs at high temperatures and superplastic materials, such as Wootz Steel and Damascus Steel can be formed into complex shapes.

Today, ultra-high carbon steel (UHCS) is still valued for its superplastic properties and is used in the aerospace and automotive industries as well as for traditional uses, such as knives, axels and punches that are used in metal forming.

Despite the vast technological advances that have been made over 2300 years since Wootz steel was first used to make the highly prized Damascus blade, we’re using the 21st century version of ultra high carbon steel for much the same purpose today.

The remarkable properties of steel make it one of the most versatile and resilient materials on earth. At ShapeCUT, we keep over 5,000 tonnes of steel plate stock in our warehouse, covering all grades, sizes and thicknesses, as well as non-standard sizes. Our range of steel cutting and shaping services are performed by modern efficient machines, operated by our highly trained and trusted team of fabricators, focussed on delivering the best quality steel cutting and shaping services for our customers. For more information about our profile cutting services, contact us today.

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