- Carbon, carbon content is higher, the hardness of steel is higher, but its plasticity and toughness is poor; - Sulfur: is the harmful material in steel, high sulfur steel under high temperature pressure process, easy to brittle fracture, is usually called hot brittleness; - P: can you make the plasticity and toughness of steel decreases obviously, especially at low temperature is more serious, this a kind of phenomenon is called cold brittleness. In the high-quality steel, sulfur and phosphorus to strict control, but on the other side acol surface in low carbon steel containing high sulfur and phosphorus, can make its cutting brittle, is good for improving cor steel cutting can be; - Manganese: can improve the strength of the steel, can weaken and eliminate the bad influence of sulfur, and can improve the hardenability of steel, high alloy steel (high manganese content High manganese steel) Has good abrasion resistance and other physical properties; - Silicon: it can improve the hardness of steel, but the plasticity and toughness, electrotechnical steel containing a certain amount of silicon, can improve soft magnetic properties; - W: can improve the red hardness of steel and heat intensity, and can improve the wear resistance of steel; - Cr: can improve the hardenability of steel and resistance to wear, can improve the corrosion resistance of steel and antioxidant effect; - Vanadium: can grain refining steel with the organization, improve the strength of the steel, toughness and wear resistance. When it is in high temperature melting into austenite, can increase the hardenability of steel; Conversely, when it is in the carbide form, will reduce its hardenability; - Mo: can obviously improve the hardenability of steel and heat intensity, prevent the temper brittleness, improve the remanence and coercivity; - Titanium: can grain refining steel with the organization, so as to improve the strength and toughness of the steel. In stainless steel, titanium can eliminate or reduce steel intergranular corrosion phenomenon; - Nickel: can improve strength and toughness of steel, improve the hardenability, high content, can significantly change some physical properties of steel and alloys, improve the corrosion resistance of steel; - B: when the steel contains trace amounts of ( 0. 0010. 005%) When boron steel hardenability can be exponentially increase; - Aluminum: can refining steel grain organization, aging resistance minimizing carbon steel. Improve steel toughness at low temperature, also can improve the oxidation resistance of steel, abrasion resistance and fatigue strength of steel, etc. ; - The prominent role of copper: it is to improve the ordinary atmospheric corrosion resistance of low alloy steel, especially more obvious when using with phosphorus.