Alloys: Wootz Steel

A high-carbon crucible steel, the history of wootz steel dates back to over 2,000 years ago in the south of India. Though the exact timeline of this alloys invention is unknown, historical records suggest it existed as early as 300-500 BCE. The word wootz is an anglicized version of ukku or urukku, what the steel was known as by the locals in the Dravidian languages.

Wootz steel is characterized by a banded microstructure. Higher carbon varieties contain carbides in a martensitic or pearlitic structure, while lower carbon varieties contain ferrite and pearlite bands (because of its age, there is no set composition for wootz steel). Distinct patterns known as wave, ladder, and rose patterns can be created based on processing. Damascus steel, meanwhile, is merely wootz steel that has been forged into sword blades, and acquired its name from wootz steel that was imported to the city of Damascus before being further processed.

India maintained secrecy around the production of wootz steel for centuries, and thus managed to maintain their status as the primary producer until the 19th century, when Europeans began to produce it as well. The crucible process used to create it involves heating the iron for several days in a clay crucible before slow cooling.

Sources/Further Reading: (Images 1 and 3 - Ancient Origins) (Image 2 - Wikipedia) (ThoughtCo.) (Noblie) (Indian Institute of Science) (Matthew Forde Military Antiques) (Ancient Science) (National Institute of Advanced Studies, Bangalore)