Carbon steel is used in modern industry first, the largest amount of basic materials. The world's industrial countries, in efforts to increase high-strength low-alloy steel and alloy steel production, but also paid great attention to improving the quality of carbon steel, expanding variety and scope of use. The current output of carbon steel in various countries in the proportion of the total output of steel, some remained at about *0%, it is not only widely used in buildings, bridges, railways, vehicles, ships and machinery manufacturing industries, but also in the modern petrochemical industry , ocean development, etc., have also been widely used