China has a history of five thousand years. This long history has given birth to a rich and splendid culture. Many technologies mastered by the ancients were later lost! When people lament the greatness of the ancients, they can't help but feel sorry for the loss of these technologies. A sword was discovered in the Terracotta Warriors and Horses of Qin Shihuang. The technology used in it was more than two thousand years ahead of the world. However, this technology was eventually lost in China and was patented by the Germans!
In 1974, a farmer in Lintong County, Shaanxi Province accidentally discovered pottery fragments while digging a well and reported it to the government. After excavation by the archaeological team, an unprecedented scale of terracotta warriors and horses appeared in front of people. Experts speculate that these are the burial objects of Qin Shihuang. From the terracotta warriors and horses, we can also see the majesty of Qin Shihuang's army when he unified the six countries. It is definitely called a "miracle of the world"! The Terracotta Warriors and Horses not only unearthed lifelike terracotta warriors and horses, but also discovered many advanced weapons!
A sword was found in the Qin Terracotta Warriors. We know that weapons at that time were generally made of bronze. The smelting technology of bronze is relatively simple, but bronze is relatively brittle, so bronze swords are generally short and too long. It is easy to break. A bronze sword was discovered in Pit No. 2 of the Terracotta Warriors and Horses. To the surprise of archaeological experts, this bronze sword was still perfectly preserved after more than two thousand years! After the experts removed the rust on the surface, the bronze sword immediately emitted a frightening cold light. The experts tested it and actually penetrated 12 layers of newspapers at once!
Why is this sword still as bright as new after more than 2,000 years? This not only aroused the interest of archaeologists, but also made scientists very interested. They were eager to know what methods our ancestors used at that time to ensure that the bronze sword would not rot or rust after two thousand years. Scientists used modern scientific methods to conduct testing and discovered that there was actually a 10-micron oxide film on the surface of the bronze sword, which contained 2% chromium. When Chinese scientists announced that this technology was used on the bronze swords of the Qin Terracotta Warriors and Horses, it immediately caused a shock in the world. Why is this?
It turns out that this technology is called "chromium salt oxidation treatment". It is only in modern times that countries around the world have mastered this technology to prevent metal from rusting. Germany invented this technology in 1937 and applied for a patent. Later, Americans also discovered the secret of chromium salt oxidation and applied for a patent. To implement this treatment method in foreign countries, sophisticated machines and complex processes are required. As for how the craftsmen of the Qin Dynasty discovered and used this technology for more than 2,000 years, there is no record in our history books, so we naturally have no way of knowing. What we can know is that the bronze sword treated with chromium salt has corrosion resistance and extremely strong toughness.
One of the swords crushed a 150-kilogram terracotta warrior and horse, and the sword bent more than 45 degrees. However, after the archaeological experts removed the terracotta warrior and horse, the bronze sword not only did not break, but recovered instantly. As it was, all the experts present were stunned! 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 been lost now, which is really regrettable!