Alloy steel S355J2W

The chemical composition of S355J2W steel plate is mainly composed of a variety of elements. The following are its main elements and their content ranges:

Carbon (C): less than or equal to 0.16%
Silicon (Si): less than or equal to 0.5%
Manganese (Mn): 0.5%~1.5%
Phosphorus (P): less than or equal to 0.025%
Sulfur (S): less than or equal to 0.025%
Nickel (Ni): less than or equal to 0.65%
Chromium (Cr): 0.4%~0.8%
Molybdenum (Mo): less than or equal to 0.3%
Copper (Cu): 0.25%~0.55%
Niobium (Nb): 0.015%~0.06%
Vanadium (V): 0.02%~0.12%
The content of these elements determines the strength, toughness, corrosion resistance and other properties of the steel plate. Among them, the carbon content is low and the alloying element content is moderate, which makes the S355J2W steel plate have good comprehensive mechanical properties and welding performance.

There are significant differences between alloy steel and ordinary steel in many aspects.

First of all, from the composition point of view, in addition to iron and carbon, alloy steel also contains other alloying elements, such as chromium, molybdenum, manganese, nickel, silicon, etc. These elements can significantly improve steel's performance characteristics, including strength, hardness and corrosion resistance. In contrast, the main components of ordinary steel are only iron and carbon, with the carbon content generally not exceeding 2%, which makes the performance of ordinary steel relatively average.

Secondly, from a performance perspective, alloy steel has special properties such as high strength, high toughness, wear resistance, corrosion resistance, low temperature resistance, and high temperature resistance. The improvement of these properties is mainly due to the addition of alloy elements and appropriate processing technology. Although ordinary steel also has high strength, good toughness, wear resistance and corrosion resistance, its performance is not superior compared to alloy steel.

In addition, the uses of the two are also different. Due to its excellent properties, alloy steel is widely used in various fields that require high material performance, such as petroleum, chemical industry, aerospace, etc. Ordinary steel is more used in some ordinary manufacturing industries.

To sum up, there are obvious differences between alloy steel and ordinary steel in terms of composition, performance and use. When choosing which steel to use, comprehensive considerations should be made based on specific needs and scenarios.