The evolution process of welding

Welding technology emerged with the smelting and production of metals such as copper and iron, as well as the application of various heat sources. The main welding methods in ancient times were casting welding, brazing, forging welding, and riveting welding. 2500 BC ago, the Babylonians and Indus civilizations had already reached a high level of hot and cold processing of copper and iron metals, and were able to manufacture metal utensils using welding methods such as forging and casting, and engraved with text. The representative culture at this time is the Harappan culture.
The iron edged copper axe made in the Shang Dynasty of China is a cast and welded piece of iron and copper, with a surface where the fusion line between copper and iron is winding and well joined. During the Spring and Autumn Period and the Warring States Period, there were many coiled dragons on the bronze pedestal of Jiangu in the tomb of Marquis Yi of Zeng, which were connected by segmented brazing. After analysis, the composition used is similar to that of modern soft solder. Swords and knives made during the Warring States period have steel blades and wrought iron backs, usually forged and welded by heating. According to the book "Tian Gong Kai Wu" written by Song Yingxing during the Ming Dynasty, in ancient China, copper and iron were heated together in a furnace and forged into knives and axes; Sprinkle yellow mud or finely sieved Chenjiubi soil on the interface and weld large ship anchors in sections. In the Middle Ages, weapons were also made by forging and welding in Damascus, Syria.