Chromium steel, commonly known as steel, is considered a recent construction invention, but new evidence suggests that ancient Persians stumbled upon an early version of this alloy about 1,000 years ago. Which is surprising for archaeologists.
According to the new, the old Percy dates back to the 11th century AD. In the early 1930’s, alloys made of chromium steel were made Search Published today in the Journal of Archeology. This steel was probably used to make swords, daggers, weapons and other things, but these metals also contained phosphorus, which made them weak.
Rachel Alipore, lead author of the new study and an archaeologist at University College London, said in an email: “This special crucible steel made from fans contains about 1% to 2% chromium and 2% phosphorus.
Archaeologists and historians, up to this point, were absolutely certain that chromium steel (not to be confused with chrome – that’s it). Something else) Was a recent invention. And in fact, as we know it was developed in the 20th century today and contains far more chromium than steel produced by the ancient Persians. Alipore said the ancient Persian chromium steel was “not absurd.”
The new paper provides the earliest evidence of the consistent and deliberate addition of a chromium mineral, possibly chromite, to a chromium steel charge – resulting in the deliberate production of a low-chromium steel, the researchers wrote. ,” the study.
The translation of medieval Persian manuscripts led the research team to Chahak, an archeological site in southern Iran. Chahak was an important center for steel production, and is the only archeological site in Iran with evidence of steel making, in which iron is combined with long tular bular crucibles, other minerals and organic matter, which Is. Then seal and heat in a furnace. After cooling, the crucifix is broken and a pot is removed. This technique was important in many cultures, including the Vikings.
“Crucible steel is generally a very high quality steel,” said Alipore. “It does not contain impurities and is ideal for the production of weapons and ammunition and other equipment.”
The main handwriting used in the study was written by the Persian polymath Abu-Rehan Biruni, dating to the 10th or 11th century AD. Entitled “Al-Jamhir F-Marifah Al-Jawahar” (translated in “A Brief to Know Gems”), the manuscript offers instructions on how to make crucible steel, but also includes a mysterious compound. Ruskhtaj (Meaning “burn”), which researchers described and later identified as a chromite sand.
Crucible residue containing embedded part of slag. (Image: Raheel Alipur / UCL Archeology)
Excavation at Chahak has resulted in the discovery of residual coal in the old crucible slag (waste material left over from the separation of the metal). The radiocarbon dating of this coal dates back to the 10th and 12th centuries AD. Received a date range between. A scanning electron microscope was used to analyze the slag samples, which showed traces of ore mineral chromite. Finally, the analysis of the steel particles found in the slag shows that the fan crucible steel contains between 1% and 2% chromium by weight.
“Chromium crucible steel made in Chahik is known to contain only chromium of its kind, an element that is important to us in the production of modern steels such as tool steel and stainless steel,” said Alipore. Told. “Fan chromium crucible steel would be similar to modern tool steel in terms of its properties,” and “the strength and hardness of the chromium material would increase the properties required for tool making.”
“Persian crucible steel artifacts can be found in museums around the world, and we already know that soluble steel was used to make wired weapons, armor, antiques and other tools,” he said. Chahak is also mentioned in historical manuscripts as a place where blades and swords were made, but the accounts also state that the blades were sold at a very high price, but they were fragile, so they Lost value.
Phosphorus, which was detected during the analysis, was added to reduce the melting point of the metal, but also to reduce some hardness, which would later weaken the metal.
A large portion of the steel stuck in the crucible slag. (Image: Raheel Alipur / UCL Archeology)
Nevertheless, the research points to a specific Persian tradition of steel making, which in itself is very important. To the best of the author’s knowledge, the special chromium material found in fan steel can be used to distinguish it from other artistic objects.
“The previous evidence of steel studied by scholars relates to steel production centers in India, Sri Lanka, Turkmenistan and Uzbekistan,” Alipore said. “None of them detect chromium. Therefore, chromium as an essential component of fan crucible steel production has not yet been identified in any other known crucible steel industry. “In which he said:” This is very important, because now we can find this element in the important things of steel and find them in their production center or method. “
To this end, researchers are hoping to share their findings with museum experts and help date and identify objects with this unique chromium steel signature.
