Re: I thought steel was the other way around
Wiley Horne
Yes, that’s what the Bessemer process does.
What I understand: Before there was Bessemer, there were the Hittites in Anatolia developing iron-making starting around 2000BC—the beginning of the Iron Age. The ore smelting did produce a brittle product—blooms or pigs—with all sorts of inclusions, including too much carbon. They had the problem that Bessemer later solved. To get something usable out of the blooms, the blooms were reheated, hammer forged, reheated again, more forging—all to reduce the carbon and other inclusions—in short, to refine the iron and make it more ductile and usable. The product of the reheating and forging was wrought iron.
The wrought was highly variable, of course. In medieval times, the Swedes developed a standard wrought of high-quality—the ‘osmunds’. It was standardized in weight and purity to the point that it became a sort of barter currency as well as a high-value export.
Steel thus developed from carburizing (or recarburizing) the wrought iron. There appear to be numerous variations on the transition from cast to wrought to steel—I’ve read that the Han Chinese mixed cast and wrought iron to get to the right C content for steel.
An early commercialization was ‘wootz’ steel made in Southern India, shipped over the seas starting as early as 600BC, as well as transported over the Silk Road, to the known world.
I was curious about Roman swords: Starting 16BC, mountain districts in modern Austria and Slovenia were added to the Roman Empire as Noricum. Steel was made in Noricum, and was highly regarded as sword material.
Wiley