How did the ancients make bronze into a sharp sword?

We know that in the production of swords in the metal material, bronze is considered a low-grade weapon material, but in ancient times before the emergence of iron, bronze sword has by virtue of its sharpness, toughness of the characteristics of the battlefield galloped, mentioning the transmission to the present day the sword of King Goujian, King Wu Fuzhai sword, fishbowl sword, we are even more admired by the ancients of the wisdom and craftsmanship.

So, how did the ancients in technology and bronze material performance limitations, to improve the combat effectiveness of bronze swords?

The answer is the bronze composite production technology invented by the ancients. It greatly improved the performance of the bronze sword by adjusting the production process, and has been used to this day, and even spread to overseas, famous all over the world!

What is the composite process? What is different from the ordinary bronze sword casting method?

The casting method of composite swords is very different from that of ordinary copper swords: for ordinary swords, the body of the sword is cast once and finished; for composite swords, it is cast twice.

The following look at the bronze composite sword casting process:

①Take a special spine mold used to cast the spine of the sword, and, on both sides of the spine of the sword reserved for embedded grooves;

②The casting of the spine of the sword on the other mold, the casting of the sword blade;

③The final use of the mortise and tenon embedded casting, so that the spine of the sword and sword casting blade more precise.

Say it.

To put it more bluntly, the technical principle of the bronze composite sword is to use different compositions of bronze, embedded casting into the inside of the spine and the outside of the sword.

The blade and the spine are tightly embedded, and the surface is bright and sharp.

Because the spine and blade of the sword are made of different ratios of bronze, the surface of the sword can be seen as a result of the difference in the material is obviously different colors, so some people call the bronze composite sword "two-color sword" or "copper inlaid sword".

The middle ridge of the sword contains low tin, greatly improving the toughness of the sword, so that the sword is not easy to break; and the body of the sword contains a relatively high amount of tin, so, and greatly improve the hardness of the sword, so that the sword blade is exceptionally sharp, greatly improving the lethality of the bronze sword in combat.

The bronze composite sword is soft on the inside and steel on the outside, rigid and flexible, sharper and tougher than ordinary bronze swords. This is why the Yue Wang Goujian Sword is still sharp after thousands of years, easily cutting through twenty sheets of paper.

▲Bronze sword (modern casting)

This composite sword technology first appeared in the early Warring States period, the ancients creatively used the law of bronze alloy composition ratio, reflecting the ancient craftsman's high level of craftsmanship, but also is the ancient Chinese bronze sword from the main piercing cuts to the chopping of the technical changes.

But, in the bronze sword unearthed so far, the composite sword is still relatively small, perhaps with its complexity of the production process, such as hidden in the Palace Museum of the less Yu sword, the Yue Wangzhou sentence sword, the Hainan Provincial Museum of the Yue Wang Qi Bei ancient sword, are composite sword.

The composite technology of bronze swords was also applied to the production of iron swords in the Han Dynasty, and later, the technology of steel cladding and embedded steel was also formed and spread to Japan, and the composite structure has become the magic weapon of samurai swords proudly in the world to this day.