(1) carbon; the higher carbon content, the higher the hardness of steel, but its plasticity and toughness of the worse.
(2) sulfur; is the steel of harmful debris, a higher sulfur content of steel for pressure processing at high temperatures, easy to rattle, often called hot shortness.
(3) P; make the plasticity and toughness of steel decreased significantly, particularly at low temperatures is more serious, a phenomenon called cold brittleness.In the high-quality steel, sulfur and phosphorus must be strictly controlled.But on the other hand to see, in low carbon steel with high sulfur and phosphorus, can easily cut them off, to improve the machinability of steel can be beneficial.
(4) manganese; can increase the strength of steel, can weaken and eliminate the adverse effects of sulfur, and can increase the hardenability of steel, high manganese content of high-alloy steel (high manganese steel) has a good abrasion resistanceand other physical properties
