Carburized Steels (GB 3203-82)
Carburized steels, also known as carbonized steels, are steels that have been subjected to a process of carburization in order to increase their resistance to wear, corrosion and fatigue. Carburization is a process of chemical reaction that takes place at elevated temperatures, and involves the addition of carbon to the iron-based alloy. The result of carburization is a strengthened and hardened material, that is capable of withstanding high loads and extreme temperature variations.
Carburized steels are widely used in industries such as aerospace, marine, automotive, chemical and industrial applications. The steel is often used as an outer wear surface on structural components, such as gears and bearings, due to its increased resistance to abrasion and corrosion. In addition, carburized steels offer improved mechanical properties, increased dimensional stability and greater strength at elevated temperatures.
Carburized steels have the highest strength and hardness of all metals, and are therefore highly preferable for applications that require the use of materials that can withstand frequent wear and tear. Carburized steels can be designed for specific tasks, such as for a cylinder head for an automotive engine that requires increased hardness, impact resistance and fatigue performance.
Carburization involves careful control of temperature, as it can cause defects in the steel, such as a decrease in corrosion resistance, cracking or deterioration in mechanical or thermal properties. The carburization process is typically done in an atmosphere of hydrogen and carbon compounds, which is why it is essential to ensure the proper selection and preparation of alloyed steels for carburization.
In GB 3203-82, carburized steels are classified in accordance to their metallurgical structure, hardness and chemical composition. The standard includes several grades of steel, ranging from low to high strength. The steel grades are divided into four categories, according to their strength: grade 16, grade 25, grade 36 and grade 45. The higher the grade, the higher the strength and the greater the ductility and toughness.
Carburized steels have a range of applications, including in the manufacturing of ball bearings, engine parts, tools, shafts, and various other industrial components. They are used in a wide variety of industries, including aerospace, automotive, chemical and rail. Carburized steels are considered to be the ideal material for certain applications, due to their enhanced properties, such as resistance to wear and tear, high strength, excellent fatigue resistance and high thermal conductivity.
