1. Carbon (C) : the yield point and tensile strength of steel increase with the increase of carbon content, but the plasticity and impact are reduced, when the carbon content is over
When the welding performance of steel is over 0.23%, [SCALE STEEL]the carbon content of low alloy structural steel used for welding is generally not more than 0.20%.
High carbon content will reduce the atmospheric corrosion resistance of steel, in the open yard of high carbon steel is easy to rust; In addition, carbon can increase Cold brittleness and aging sensitivity of steel.
2. Silicon (Si) : in the process of steel making, [SCALE STEEL]add silicon as a reducing agent and deoxidizer, so the killed steel contains 0.15-0.30% silicon.
If the silicon content in the steel exceeds 0.50-0.60%, silicon is considered an alloying element. Silicon can significantly improve the elastic limit, yield point and Tensile strength, so widely used as spring steel. Adding 1.0-1.2% silicon to quenched and tempered structural steel can increase the [SCALE STEEL]strength by 15-20%.
The combination of silicon and molybdenum, tungsten, chromium, etc., has the effect of improving corrosion resistance and oxidation resistance, and can make heat-resistant steel. Low silicon content of 1-4% Carbon steel, with high permeability, used for making silicon steel sheet in electrical industry. The increase of silicon will reduce the welding performance of steel.
3. Manganese (Mn) : in the process of steel making, manganese is a good deoxidizer and desulfurizer, general steel contains [SCALE STEEL]manganese 0.30-0.50%. in When carbon steel is added more than 0.70%, even if "manganese steel", more than the general amount of steel not only has enough toughness, and has a higher
Strength and hardness, improve the quenchability of steel, improve the hot working performance of steel, such as 16Mn steel is 40% higher than A3 yield point. 11%-14% manganese steel with extremely high wear resistance, used for excavator bucket, [SCALE STEEL]ball mill liner, etc. The increase of manganese content weakens the corrosion resistance of steel and reduces the welding performance.
4. Phosphorus (P) : in general, phosphorus is a harmful element in steel, increase the cold brittleness of steel, so that the welding performance deteriorates, reduce Plastic, so that the cold bending performance deteriorates. Therefore, phosphorus content in steel is usually less than 0.045%, and high quality steel is required to be lower.
5. Sulfur (S) : Sulfur is also a harmful element in general. Make steel produce hot brittleness, reduce the ductility and toughness of steel, in Cracks are caused by forging and rolling. Sulfur is also detrimental to welding performance, reducing corrosion resistance. So sulfur content is usually less than 0.055%, high quality steel requirements [SCALE STEEL]less than 0.040%. Adding 0.08-0.20% sulfur to steel can improve machinability Often called free cutting steel.
6. Chromium (Cr) : in structural and tool steels, chromium can significantly improve strength, hardness and wear resistance, but at the same time reduce plasticity and Toughness. Chromium also improves the oxidation resistance and corrosion resistance of steel, so it is an important alloying element in stainless steel and heat-resistant steel.
7. Nickel (Ni) : nickel can improve the strength of steel, while maintaining good plasticity and toughness. Nickel has high corrosion resistance[SCALE STEEL] to acid and base Strength, rust resistance and heat resistance at high temperature. However, as nickel is a scarce resource, other alloying elements should be used as far as possible Nickel chrome steel.
8. Molybdenum (Mo) : Molybdenum can refine the grain of steel, improve hardenability and thermal strength performance, and maintain sufficient strength and resistance at high temperature Creep ability (long-term under high temperature stress, deformation, called creep). The mechanical properties of structural steel can[SCALE STEEL] be improved by adding molybdenum. It can also inhibit the brittleness of alloy steel due to fire. Redness can be improved in tool steel.
9. Titanium (Ti) : titanium is a strong deoxidizer of steel. It can make the inner structure of steel compact, refine grain force; Reduced age sensitivity And cold brittleness. Improve welding performance. Intergranular corrosion of [SCALE STEEL]cr 18 ni 9 austenitic stainless steel can be avoided by adding appropriate ti.
10. Vanadium (V) : vanadium is an excellent deoxidizer of steel. Adding 0.5% vanadium to steel can refine grain structure and improve strength and toughness. vanadium
The carbides formed with carbon can improve the resistance to hydrogen corrosion at high temperature and pressure.
11. Tungsten (W) : tungsten melting point is high, significant, is expensive alloy elements. Tungsten forms tungsten carbide with carbon[SCALE STEEL] and has high hardness and resistance Grinding. The addition of tungsten to tool steel can significantly improve the red hardness and thermal strength, used as cutting tools and forging dies.
12. Niobium (Nb) : Niobium can refine grain and reduce steel overheating sensitivity and temper brittleness, improve strength, but the plasticity and toughness The decline. Adding niobium to ordinary low alloy steel can improve the corrosion resistance of atmospheric and high temperature hydrogen, nitrogen and ammonia. [SCALE STEEL]Niobium can Improve welding performance. Intergranular corrosion can be prevented by adding niobium into austenitic stainless steel.
13. Cobalt (Co) : Cobalt is a rare precious metal, mostly used in special steels and alloys, such as hot steel and magnetic materials.
14. Copper (Cu) : Wisco with daye ore smelting steel, often contain copper. Copper improves strength and toughness, especially for atmospheric[SCALE STEEL] corrosion The corrosion performance. The disadvantage is that it is easy to produce hot brittleness during hot working, and the plastic content of copper exceeds 0.5% is significantly reduced. When copper content is less than 0.50% has no effect on weldability.
15. Aluminum (Al) : aluminum is commonly used in steel deoxidizer. Adding a small amount of aluminum to steel can refine grain size and improve impact toughness, such as 08Al steel for deep drawing sheet. Aluminum also has oxidation resistance and corrosion resistance, aluminum combined with chromium, silicon, can significantly improve steel High temperature performance and high temperature corrosion resistance. The shortcoming of aluminum is affecting the hot working property, welding property and cutting property of steel Machining performance.
16. Boron (B) : adding trace boron to steel can improve the density and hot rolling properties of steel, improve the strength.
17. Nitrogen (N): nitrogen can improve the strength of steel, low temperature toughness and weldability, increase the aging sensitivity. Formation of bubbles and porosity.
18. Rare Earth (Xt) : Rare earth elements refer to the 15 lanthanide elements in the periodic table with atomic numbers from 57 to 71. Actually these elements are metals, but their oxides are so earth-like that they are commonly called rare earths. Adding rare earths to steel can change the steel- The composition, morphology, distribution and properties of inclusions improve various properties of steel, such as toughness, weldability, cold workability can add rare earth into ploughshare steel can improve wear resistance.