The history of stainless steel began 1000 years earlier than we thought

A new study by archaeologists Rahil Alipour, Thilo Rehren, and Marcos Martinón-Torres has dated back a discovery that seemed consolidated: the origins of stainless steel are in Persia, nearly a millennium earlier than previously thought.

Official history has it that two English gentlemen, Woods and Clark, filed a patent in 1872 for a weatherproof and acid-resistant iron alloy containing 35% chromium. The invention and industrialization of stainless steel are inextricably linked to the name of Harry Brearley, a metallurgist also from England, who in 1913 created a steel with 12.8% chromium and 0.24% carbon.
No one knew that the Persians had already intentionally added chromium to steel 1000 years before the British - and anyone else - tried such experiments.
Archaeologists Alipour, Rehren, and Martinón-Torres analyzed finds from the Chahak site in Iran from the 11th century BC, which show the intentional and regular addition of chromium mineral to the crucible charge, which resulted in steel containing about 1% by weight of chromium. Little, compared to the one currently used for the production of stainless steel, but enough to improve the resistance to oxidation and rust of the products.
The metal was used to make armor, tools, and weapons.


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