Preliminary Study On Smelting Technology Of Iron Based On The Analysis Of The Ironware Unearthed From The Mogou Site

There is always a dispute over Chinese iron smelting origin for there are few iron smelting relics being found and iron smelting relics earlier than the 8th century are never found in China. About the iron smelting technology origin, there are two different opinions: west-origin and native-origin. Archaeological data show that around 4-6 BC, iron appeared in west-Asia region, as so, some domestic and foreign scholars tend to support the west origin. However, there are two routes of its spreading:from Xinjiang through Hexi Corridor into the Central Plains; and through the steppe zone directly into the Central Plains. With the China territory early iron products continually unearthed and continuing scientific analysis, some scholars also believe that China has its own native origin of iron and iron smelting technology. About the native origin, there are still two different views:whether it appeared and developed independently or was it influenced by Chinese bronze smelting technology.To probe the Chinese iron smelting technology origin, it not only needs a systematic analysis and research on the early unearthed iron products, but also needs to explore in depth the early iron smelting technology process. At present, the earliest artificial iron products in Mogou, China, provided new substantial data for Chinese iron smelting origin. Because their composition, microstructure analysis showed that these iron products were carburized steel after hot forging processing, this was close to the time of west-Asia origin. It provides new materials for the study of the origin of Chinese iron and iron smelting technology, and it has great significance to further study the origin of Chinese iron and iron smelting technology.As it is known to all about smelting, the bloomer iron can be made of iron ore in the solid state from restoration process at about 1000℃. The scientific analysis of the data on Chinese early bronze symbiotic characteristics and copper artifacts, showed that during early Chinese copper smelting, because of the ore choosing technical limitations, certain amount of iron ore would mix into copper ore, and they were restored into raw copper and mixed into the slag. And the technology conditions of early copper smelting can achieve a temperature of 1000 ℃, making a good restoration condition. So it can be inferred, in the process of copper smelting, if by accident mixed with iron ore, there would be bloomery iron. If it can be confirmed, then it can be inferred that Chinese early iron may come from mature copper smelting technology, which is important to the origin of Chinese iron and iron smelting technology.In order to probe whether there should be bloomery iron appearance, experiments are designed imitating the early copper smelting conditions in which the mixed ore material of iron and copper are used. And the experiment products are compared with the early red copper products and ironware from Mogou. The result shows that under 950 ℃ in the restored copper furnace, there are red copper particles wrapped in slag which had to be broken to pick up the red copper particles. This is consistent with the early archaeological copper smelting recordings. In the process of breaking the slag, some gray white, hard lumps were found. Analysis of the metallographic compositions of the copper particles, the grey lumpy products and the slag showed that they were copper and iron blocks. Simulation experiment shows the smelting at about 950 ℃, regardless of the low grade copper ores or high grade copper ores, as long as there is certain amount of iron ores, in the way of copper smelting conditions, it can produce copper particles and lump bloomery iron.Scientific analysis of iron products of Mogou and simulation experiment showed that in the copper smelting process there would by chance be block iron products, and people would find and use them in the selection process. It can be inferred that the Chinese early iron smelting technology probably originated from the mature copper smelting technology, and the 14 Century BC Mogou iron smelting site should belong to the Chinese iron smelting budding stage when iron is a product by accident in the copper smelting conditions. The findings of this study provide a new clue to the Chinese iron smelting origin, and it is to advance the study of the Chinese iron smelting origin and its early development.