The quality and performance of steel is determined according to the needs, different needs, to have different elements content.
(1) carbon; the higher the carbon content, the higher the hardness is, but its plasticity and toughness are worse.
(2) sulfur; is the harmful impurities in steel, high sulfur steel in the high temperature pressure processing, easy to crack, usually called hot brittleness.
(3) p; can make steel plasticity and toughness decreased significantly, especially at low temperature is more serious. This phenomenon is called the cold brittleness. In high quality steel, phosphorus, sulfur, and to strictly control. But from on the other hand, in low carbon steel containing high sulfur and phosphorus, can make its cutting easily broken of improved steel can cutting is beneficial.
(4) manganese steel can improve the strength, can weaken and eliminate the sulfur of adverse effects, and can increase the hardenability of steel, containing a high manganese content in high alloy steel, high manganese steel) has good wear resistance and other physical properties.
(5) silicon; it can improve the hardness of the steel, but the plasticity and toughness decreased, electrical steel with a certain amount of silicon, can improve the soft magnetic properties.
(6) tungsten; can improve the hardness and thermal strength of the steel, and can improve the wear resistance of the steel.
(7) chromium can improve the steel's quenching and wear resistance, can improve the corrosion resistance of steel and oxidation.
(8) vanadium, refined steel microstructure, improve the steel strength, toughness and wear resistance. When it is in high temperature melting into the austenite, increase of steel hardenability; on the contrary, when it in the presence of carbide morphology, it will reduce its quenching permeability.
(9) molybdenum; can significantly improve the hardenability of steel and heat resistance, prevent tempering brittleness, higher remanence and coercive force.
(10) titanium can refine the grain structure of the steel, so as to improve the strength and toughness of the steel. In the stainless steel, titanium can eliminate or reduce the intergranular corrosion of the steel.
(11) nickel; can improve the strength and toughness of steel, improve the degree of high content, can significantly change some of the physical properties of steel and alloy, improve the corrosion resistance of steel.
(12) boron; when the steel contains trace amounts of (0.005% - 0.001) B, the quenching of the steel can be increased exponentially.
(13) aluminum, refined steel microstructure, aging inhibition of low carbon steel. Improve the steel toughness at low temperatures, but also improve the oxidation resistance of the steel, improve the wear resistance and fatigue strength of steel.
(14) copper; its prominent role is to improve the resistance to atmospheric corrosion of ordinary low alloy steel, especially with the use of phosphorus is more obvious.