The role of alloy elements in tungsten steel alloys

1. Carbon (C) : with the increase of carbon content in steel, the yield point and tensile strength increase, but the plasticity and impact decrease. When the carbon content exceeds 0.23%, the welding performance of steel deteriorates, so the carbon content of low-alloy structural steel for welding generally does not exceed 0.20%. High carbon content will also reduce the atmospheric corrosion resistance of steel, high carbon steel in the open pit is easy to rust; In addition, carbon can increase the cold brittleness and aging sensitivity of steel. Tungsten steel alloy manufacturers

2. Silicon (Si) : In the process of steel making, silicon is added as a reducing agent and deoxidizer, so the sedated steel contains 0.15-0.30% silicon. If the silicon content of the steel exceeds 0.50-0.60%, silicon is considered an alloying element. Silicon is widely used as spring steel because it can significantly improve the elastic limit, yield point and tensile strength of steel. The strength of tempered structural steel can be increased by 15-20% by adding 1.0-1.2% silicon. Silicon and molybdenum, tungsten, chromium, etc. combine to improve corrosion resistance and oxidation resistance, can be made of heat-resistant steel. Low carbon steel containing 1-4% silicon, with very high permeability, used in the electrical industry to make silicon steel sheet. The increase of silicon will reduce the welding performance of steel.

3, manganese (Mn) : in the process of steelmaking, manganese is a good deoxidizer and desulfurizer, general steel manganese 0.30-0.50%. When more than 0.70% is added to carbon steel, it is considered as "manganese steel". Compared with the general steel, steel not only has enough toughness, but also has higher strength and hardness, improve the quenching of steel, improve the thermal working performance of steel, such as 16Mn steel is 40% higher than A3 yield point. Steel with manganese content of 11-14% has very high wear resistance and is used for excavator bucket, ball mill lining board, etc. The increase of manganese content weakens the corrosion resistance and welding performance of steel.

4. Phosphorus (P) : In general, phosphorus is a harmful element in steel, which increases the cold brittleness of steel, deteriorates the welding performance, reduces the plasticity, and deteriorates the cold bending performance. Therefore, it is usually required that the phosphorus content in steel is less than 0.045%, and the requirement of high-quality steel is lower.

5. Sulfur (S) : Sulfur is also a harmful element in general. Make the steel produce hot brittleness, reduce the ductility and toughness of steel, cause cracks in forging and rolling. Sulfur is also bad for welding performance, reducing corrosion resistance. Therefore, sulfur content is usually required to be less than 0.055%, and quality steel is required to be less than 0.040%. The machinability can be improved by adding 0.08-0.20% sulfur to steel, which is usually 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 can also improve the oxidation resistance and corrosion resistance of steel, so it is an important alloy element of 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 to acid and alkali, rust and heat resistance at high temperature. However, as nickel is a scarce resource, other alloying elements should be used instead of nickel chromium steel.

8, molybdenum (Mo) : molybdenum can make steel grain refinement, improve hardenability and thermal strength, at high temperature to maintain sufficient strength and creep resistance (long-term under high temperature stress, deformation, known as creep). The mechanical properties of structural steel can be improved by adding molybdenum. The brittleness of alloy steel caused by fire can also be inhibited. Redness can be improved in tool steel.

9. Titanium (Ti) : Titanium is a strong deoxidizer in steel. It can make the internal structure of steel compact, refine grain strength; Reduce aging sensitivity and cold brittleness. Improve welding performance. Intergranular corrosion can be avoided by adding appropriate titanium to Cr 18 Ni 9 austenitic stainless steel.

10, Vanadium (V) : Vanadium is an excellent deoxidizer of steel. Adding 0.5% vanadium in steel can refine grain structure and improve strength and toughness. The carbides formed by vanadium and carbon can improve the resistance to hydrogen corrosion at high temperature and pressure.

11, tungsten (W) : tungsten melting point is high, significant, is your alloy element. Tungsten carbide forms with carbon and has high hardness and wear resistance. Adding tungsten to tool steel can significantly improve the hardness and thermal strength, which can be used as cutting tools and forging dies.

12, Niobium (Nb) : Niobium can refine the grain and reduce the overheating sensitivity and tempering brittleness of steel, improve the strength, but the plasticity and toughness decreased. The corrosion resistance of hydrogen, nitrogen and ammonia at high temperature can be improved by adding niobium to common low alloy steel. Niobium can improve welding performance. Adding niobium to austenitic stainless steel can prevent intergranular corrosion.

13, cobalt (Co) : Cobalt is a rare precious metal, mostly used in special steel and alloys, such as hot steel and magnetic materials.

14, copper (Cu) : Wisco with Daye ore smelting steel, often contains copper. Copper can improve strength and toughness, especially atmospheric corrosion. The disadvantage is that it is easy to produce thermal brittleness during hot working, and the plasticity decreases significantly when the copper content exceeds 0.5%. When the copper content is less than 0.50%, the weldability is not affected.

15, aluminum (Al) : Aluminum is commonly used in steel deoxidizer. The addition of a small amount of aluminum to steel can refine the grain and improve the impact toughness, such as 08Al steel for deep drawing sheet. Aluminum also has oxidation resistance and corrosion resistance. Aluminum combined with chromium and silicon can significantly improve the high temperature non-peeling performance and high temperature corrosion resistance of steel. The disadvantage of aluminum is that it affects the hot working properties, welding properties and machining properties of steel.

16, boron (B) : Adding a trace of boron in steel can improve the density and hot rolling performance of steel, improve strength.

17, nitrogen (N): nitrogen can improve the strength of steel, low temperature toughness and weldability, increase aging sensitivity.

18. Rare Earth (Xt) : Rare earth elements refer to 15 lanthanides in the periodic table with atomic numbers 57-71. These elements are all metals, but their oxides are so earth-like that they are conventionally called rare earths. Adding rare earth into steel can change the composition, form, distribution and properties of inclusions in steel, thus improving various properties of steel, such as toughness, weldability, cold working performance. The wear resistance of ploughshare steel can be improved by adding rare earth.