Iron smelting industry:

Iron was used in the Western Zhou Dynasty;

The softening treatment technology of cast iron was invented in the Spring and Autumn Period and the Warring States Period, which was a great achievement in the history of iron smelting in the world, more than 2000 years earlier than in Europe.

Han Dynasty: During the Western Han Dynasty, the iron smelting industry was divided into official and private. Coal became the fuel for ironmaking, and people invented quenching technology; DuDu invented the water platoon in the Eastern Han Dynasty, which made China lead the world in iron smelting for a long time. Wanhe Palace is a famous iron smelting center;

Sui and Tang dynasties: cutting, grinding, welding and other processes were widely used;

Liao-Jin period: the level of iron smelting in Liao-Jin was high;

In the middle and late Ming Dynasty, the iron smelting industry in Foshan, Guangdong Province produced six or seven thousand kilograms of iron a day.

Understanding: In the era of agricultural civilization, the development of iron smelting industry is an obvious sign of the progress of productive forces, which has effectively promoted social change and progress.