1974 a farmer in Lintong county, Shaanxi province accidentally found pottery pieces while drilling a well and reported them to the government. After the excavation of the archaeological team, an unprecedented terracotta warriors and horses appeared in front of people. Experts speculate that this is the funerary object of Qin Shihuang. From the Terracotta Warriors, we can also see the majestic posture of the army when Qin Shihuang unified the six countries, which is definitely a "world miracle"! Terracotta Warriors not only unearthed lifelike terracotta warriors and horses, but also found many advanced weapons!
A sword was found in the terracotta warriors and horses of Qin Dynasty. As we know, weapons at that time were generally made of bronze. The smelting process of bronze is relatively simple, but bronze is fragile, so bronze swords are generally short. If they are too long, they will break easily. A bronze sword was found in pit 2 of Terracotta Warriors. To the surprise of archaeologists, this bronze sword is still well preserved after more than 2000 years! After the experts removed the soil rust from the surface, the bronze sword immediately gave off a frightening cold light. Experts tested it, and it actually penetrated the 12 newspaper at once!
Why is this sword as bright as new after more than 2000 years? This not only aroused the interest of archaeologists, but also interested scientists. They are eager to know what methods our ancestors used at that time to ensure that bronze swords would not rot and rust after two thousand years. Scientists use modern scientific methods to detect, only to find that there is actually a layer of 10 micron oxide film on the surface of bronze sword, which contains 2% chromium. When scientists in China announced that this technology had been used in the bronze swords of Qin Terracotta Warriors, it immediately caused a worldwide shock. Why?
It turns out that this technology is called "chromium salt oxidation treatment", and all countries in the world have mastered this technology in modern times to keep metals from rusting. Germany invented this technology in 1937 and applied for a patent, and then Americans also discovered the mystery of chromium salt oxidation and applied for a patent. In order to realize this treatment method abroad, it is necessary to use sophisticated machines and complex technological processes. As for how the craftsmen of the Qin Dynasty discovered and used this technology for more than two thousand years, it is not recorded in our history books, so it is naturally impossible to know. It can be known that the bronze sword treated with chromium salt has strong corrosion resistance and toughness.
One of the swords crushed a terracotta warrior weighing150kg, and the blade was bent over 45 degrees. However, after the archaeologists removed the Terracotta Warriors, the bronze sword was not broken, but instantly restored to its original state, and the experts present were dumbfounded! With such advanced weapons, it is no wonder that Qin Shihuang was able to unify the six countries. It's a pity that these advanced technologies have long been lost. What a pity!