In the martial arts novel "Yitian Slaughtering Dragon", the Yitian Sword and the Dragon Slaying Sword are the peerless divine soldiers on the rivers and lakes, and ordinary weapons are broken when touched, and only the Ming Sect's Sacred Fire Order can fight with one. Since ancient times, cutting gold and cutting jade and cutting iron like mud are the criteria for judging the sharpness of the sword, and once one of the two needs is met, it can be called "divine soldier". However, in ancient times, when iron smelting technology was not developed, was there really a sword that "cut iron like mud"?
The phrase "cut iron like mud" comes from the forty-first time of the Romance of the Three Kingdoms, and the original text records that the green sword cut iron like mud, and the sharpness was incomparable. According to folklore, the Green Dragon Sword has been stolen by tomb robbers, and when the thieves passed through Fuxian Lake by boat, the boat accidentally capsized, and the tomb robber and the Green Dragon Sword sank to the bottom of the lake together, and are still missing. However, although the steel sword is missing, we can get a glimpse of it from the Yue King's sword.
When the Yue King's sword was unearthed, there was almost no rust on the sword body, and the sharpness was still there. Archaeologist Tan Weisi once took the Yue Wang's sword and lightly swiped it on a stack of paper, and the result was that 26 pieces were easily broken, and the test clips were recorded in the CCTV documentary "Ancient Swords". In 1977, after the yuewang gou jian sword was tested by Fudan University, it was found that the content of tin in the blade of the sword was particularly high. You know, the casting and hardness of tin are greater than pure copper, and the sharpness can be imagined.
However, after all, the Yue King's sword is a rare divine soldier in the world, and in ancient China, the main manufacturing material of weapons was still iron. From the carbon content division, iron is divided into pig iron, wrought iron and steel, carbon content of more than 2% is called pig iron; carbon content of less than 0.05% is called wrought iron; carbon content between 0.05% and 2%, called steel. In the early days of smelting technology, iron furnaces were small, iron ore and carbon were placed in layers, and blowers were blown.
When the temperature inside the box reaches 1000 degrees, the iron blocks sink to the bottom of the furnace, and the blacksmith removes the iron after the furnace has cooled. However, at that time, iron was only a spongy wrought iron block, not only loose structure, but also contained a lot of oxides, after repeated forging, extrusion of impurities, in order to obtain a more pure wrought iron. If you want to get steel, you should use wrought iron as a raw material to continue to heat carbon absorption in the fire to increase the carbon content. After repeated pounding and removing impurities, steel can be obtained.
In general, the iron in cutting iron such as mud usually refers to wrought iron, which is very soft in texture and even the bone. In addition, the ancients did not know much about metals, becoming roughly the same, iron is called "iron", brass is also called "iron". In the "Water Margin", there is a bridge section, Yang Zhi happened to encounter The Second Bull when selling knives, and Niu Er lined up 20 copper coins in a row for Yang Zhi to cut. As a result, Yang Zhi went down with a knife, and the copper coin was divided into two halves, and Niu Er was shocked in his heart.
In fact, the tools produced by modern technology, if put into ancient times, any one piece is enough to be called "cutting iron like mud".