1. Carbon (C) Carbon determines the hardness of the steel quenching, high carbon content, high quenching hardness, but is easy to quench.

2. Silicon (Si) steel eliminates the strength and hardening of the steel, and the sedative effect can be removed during steelmaking.

3. Manganese in manganese (MN) steel is improved hardenability, and reduce the critical cooling rate, manganese forming a solid solution in ferrite during heating, and can improve the speed of steel.

4. Chromium in chromium (CR) steel is required to increase the heating temperature and extend the heating time, and there is an unfavorable side of the sensing quenching. However, chromium increases the hardenability of steel (similar to manganese), and chrome steel has high mechanical properties in the conditioning condition.

5. The molybdenum energy in molybdenum (MO) steel can improve the hardenability, and the molybdenum is small in the steel retaining.

6. Sulfur (s) Steel, the sulfide, the test, proves that when the content of sulfur is reduced, the elongation and the section shrinkage are improved, and the impact toughness value increases.

7. Phosphorus in the phosphorus (P) steel does not form a phosphemical, but it is easy to cause serious segregation, so it is a harmful element.