7th Experimental Archaeology Conference Abstract – Adrian Wrona
The production of high carbon steel directly in bloomery process. Theoretical bases and metallographic analyses of the experiment results
The Department of History, The Jan Kochanowski University in Kielce, Poland
The problem of steel making in antiquity has been intriguing the researchers who specialize in the ancient metallurgy for decades. In the course of research different explanations prevailed in the scholarship. Recent experiments of the iron smelting clearly shows that the same mechanism like in the carburizing in so-called “Aristotle furnace” may occur in appropriate conditions during the smelting operation. It is basically the same operation as the one described by O. Evenstad and Japanese oroshigane process. This consists of a superficial melting of iron fraction situated near the tuyere, which actually became a cast iron and formed a multilayer clot with varied carbon content after falling to the furnace bottom. Then, in high temperature, the carbon from eutectic structures diffuses to the surrounding areas and increases carburization degree in the whole cross-section of bloom. Steel with a high carbon content were obtained during two smelting operations performed in recent year. The occurrence of the above process may be confirmed by the presence of the eutectic structures on the surface of iron parts which did not integrate with the proper bloom. The results of the metallographic studies will be presented as well as the description of the conducted experiments. Author is also going to discuss a further questions and problems related to the topic.