In the 1990s, the price of steel plummeted: 1.992 led to the mushrooming of 8,000 development zones in China, and the steel soared to 3,900 yuan per ton in the following year, and then fell to 1.700 in 1.997.

Steel is the general name of iron-carbon alloy with carbon content of 0.02%-2. 1 1%. The chemical composition of steel varies greatly. Steel containing only carbon element is called carbon steel (carbon steel) or ordinary steel. In actual production, steel often contains different alloying elements, such as manganese, nickel and vanadium, according to different uses. The application and research of steel has a long history, but before the invention of bainite steelmaking in the19th century, the production of steel was a high-cost and inefficient work.