1. Chemical composition: The chemical composition of steel has an important impact on its performance. Common chemical components include carbon (C), sulfur (S), phosphorus (P), manganese (Mn), silicon (Si), chromium (Cr), nickel (Ni) and other elements. The content of these elements needs to be controlled within a certain range to ensure the performance and quality of steel.
2. Mechanical properties: Also called mechanical properties, this is one of the important indicators of steel quality. Key indicators include:
• Strength: refers to the ability of a material to resist deformation or breakage. Measures of strength include yield strength and tensile strength. Yield strength is the basis for determining the strength of steel in structural design, while tensile strength reflects the maximum force that steel can withstand during stretching.
• Hardness: refers to the ability of a material surface to resist the intrusion of hard objects. Common hardness indicators include Brinell hardness, Rockwell hardness and Vickers hardness. The higher the hardness, the better the wear resistance of the steel.
• Plasticity: refers to the ability of a material to deform without breaking. Plasticity indicators such as elongation and reduction of area are used to measure the formability of steel. The higher the plasticity, the better the ductility of the steel.
• Toughness: Also called impact toughness, it refers to the ability of a material to resist impact deformation. Toughness is a measure of the impact resistance of steel. The higher the value, the stronger the steel's ability to resist movement loads.
3. Physical properties: This includes the density, thermal expansion coefficient, thermal conductivity, electrical conductivity, etc. of steel. These properties have an important impact on the application of steel in various environmental conditions.
4. Process performance: mainly measures the performance of steel during processing, such as weldability, cutting processability, etc.

1. Construction and infrastructure: Steel has a wide range of applications in the construction field, such as high-rise buildings, commercial buildings, industrial buildings and sports venues. The high strength, stiffness and durability of steel make it an ideal choice for building structures and can be used to make key components such as beams, columns, piers, steel pipe trusses, etc. At the same time, steel is also widely used in infrastructure construction, such as bridges, tunnels, airports, docks, etc.
2. Automobiles and transportation: Steel plays an important role in automobile manufacturing and transportation. It is used to manufacture automobile bodies, chassis, engines and parts, etc., to meet the needs of automobiles for lightweight, high strength and durability. In addition, steel is used in the manufacture of train tracks, ship and aircraft components.
3. Machinery and industrial equipment: Steel is an indispensable material for the manufacturing of machinery and industrial equipment. It is used in the manufacture of machine tools, cranes, mining equipment, agricultural machinery and industrial pipes, among others.
4. Home appliances and consumer goods: Steel also plays an important role in the manufacturing of home appliances and consumer goods. It is used in the manufacture of products such as kitchen appliances, refrigerators, washing machines, televisions, computers and furniture, providing materials that are beautiful, durable and easy to process.
5. Medical and life sciences: Steel is also used in the medical field, such as surgical instruments, artificial bones and artificial hearts, providing support for the advancement of medical technology.
6. Aerospace: Mainly used to manufacture aircraft, engines and their key components. Its high strength, corrosion resistance and excellent mechanical properties ensure the safety and performance of aircraft.
7. Energy field: Steel is widely used in the construction of power equipment and nuclear power plants. Because steel can withstand high temperatures and pressure, it ensures the safe operation of energy equipment. Especially in new energy fields such as wind power and nuclear power, the demand for special steel continues to grow, providing key material support for the construction of wind power generation equipment and nuclear power plants.
8. Marine engineering field: Steel plays a vital role in protecting land from floods and is often used as a key material in flood control projects. At the same time, steel is also an important material for maritime transportation. Steel ships carry the vast majority of the world's cargo, ensuring an adequate supply of goods. In addition, steel also plays a key role in the development of marine renewable energy, such as tidal energy power generation devices and offshore wind power equipment, which use steel extensively.