The Effect of Sulfur on the Properties of Steel
Sulfur is an elemental element that is naturally present in some grades of steel but is more commonly added as an adjuvant to increase both the strength of the finished product as well as its hardness and wear resistance. This article will discuss the effects of sulfur on the properties of steel.
Impact on Strength
The steel grade of the steel is determined by its chemical composition, which includes a variety of elements such as carbon, manganese, phosphorus, and sulfur. When sulfur is added to steel, the addition will have a direct effect on its strength. The general consensus is that adding up to 0.2% of sulfur to the steel will increase its tensile strength and yield point. This can be beneficial when painting or coating past the yield point of the steel as it can reduce paint peeling and cracking due to excessive stretching.
Impact on Hardness
The addition of sulfur to steel can also improve its hardness and wear resistance. By adding up to 0.2% sulfur to steel, the surface hardness can be increased to approximately 40-45 HRC, significantly increasing the durability and wear resistance of the material. This improved hardness can result in improved performance after machining as it can lead to improved tool life, as well as increased accuracy of the finished products.
Impact on Corrosion Resistance
Sulfur can also have an impact on the corrosion resistance of steel. Generally, the addition of sulfur to steel can reduce corrosion resistance and has been shown to increase the rate of corrosion when exposed to certain corrosive environments, such as seawater. However, when combined with certain alloys, such as chromium, sulfur can provide an added layer of corrosion protection and effectively increase the corrosion resistance.
Conclusion
In conclusion, sulfur plays an important role in the properties of steel, as it can affect the strength, hardness, and corrosion resistance of the material. By adding up to 0.2% sulfur to steel, the strength, hardness, and wear resistance can be increased, resulting in improved performance and extended service life. However, it is important to note that the addition of sulfur can decrease the corrosion resistance of steel and should be used in conjunction with other elements if corrosion resistance is required.
