Stainless steel is a common metal material with corrosion resistance, high strength, and high-temperature resistance, so it is widely used in many industrial fields. 304 and 304L stainless steel are two of these common alloys that differ in chemical composition and properties. This article will explore the difference between 304 and 304L stainless steel in detail to help readers better understand and choose the material that suits their needs.
The Difference Between 304 and 304L Stainless Steel
Differences in Chemical Composition:
304 stainless steel: 304 stainless steel is a common 18-8 stainless steel that contains 18% chromium and 8% nickel. In addition, it also contains up to 0.08% carbon, 2% manganese, and small amounts of elements such as silicon, phosphorus, sulfur, and nitrogen.
304L Stainless Steel: 304L Stainless Steel is a low-carbon version of 304 Stainless Steel. In contrast, 304L stainless steel has a lower carbon content of up to 0.03%. This reduced carbon content helps reduce carbide deposits that develop during welding, thereby improving corrosion resistance.
Differences in Corrosion Resistance:
304 stainless steel: 304 stainless steel has good corrosion resistance and can resist general atmospheric corrosion, chemical corrosion, and corrosion in fresh water and steam.
304L Stainless Steel: Due to the low carbon content and reduced carbide deposition during welding, 304L stainless steel has better corrosion resistance in welded joints and other high-temperature environments. It is suitable for equipment and piping systems working in corrosive environments.
Differences in Welding Performance:
304 stainless steel: 304 stainless steel has good welding performance and can be connected by common welding methods (such as arc welding, TIG welding, etc.). However, carbide deposits may occur during welding, reducing corrosion resistance.
304L stainless steel: 304L stainless steel has better welding performance due to the advantage of low carbon content. Reduced carbide deposition in welded joints improves corrosion resistance after welding.
Differences in Fields of Application:
304 stainless steel: Due to its good corrosion resistance and mechanical properties, 304 stainless steel is widely used in fields with high requirements such as manufacturing chemical equipment, food processing equipment, and pressure vessels.
304L stainless steel: Due to its superior corrosion resistance in welded joints and high-temperature environments, 304L stainless steel is often used in welded components, petrochemical equipment, heat exchangers, and piping systems in high-temperature environments.
Differences in Price:
In terms of price, 304L stainless steel is higher than 304 stainless steel. 304L stainless steel is a low-carbon stainless steel, which is mainly suitable for welding processes. When welding, the use of 304L stainless steel can effectively reduce welding corrosion.
According to the hardness standard, 304 stainless steel is better than 304L stainless steel, because the level of carbon content directly affects the hardness of stainless steel. There is also 304H stainless steel series, H means high carbon content.
In Conclusion:
There are certain differences between 304 stainless steel and 304L stainless steel in terms of chemical composition, corrosion resistance, welding performance, and application fields. Selecting the right material for specific needs is critical to ensuring the performance of devices and structures. In practical applications, the required corrosion resistance, welding performance, and operating environment should be carefully evaluated, and 304 or 304L stainless steel should be selected according to specific requirements to ensure the best performance and reliability.
In daily production applications, material substitution is often involved. In people’s minds, it is only natural for the material to “replace the low with the high, and replace the thin with the thick”. In fact, this view is wrong. Substitution of materials needs to be divided into situations, such as 304 stainless steel, 304L stainless steel, and 304H stainless steel. Generally speaking, 304L stainless steel products have lower carbon content than 304 stainless steel and have better corrosion resistance. Therefore, 304L stainless steel products can be used instead of 304 stainless steel materials.
In fact, the strength of 304 stainless steel is higher than that of 304L stainless steel. When designing according to 304 stainless steel, replacing it with 304L stainless steel will result in insufficient strength. Also, when the service temperature of austenitic stainless steel is higher than 525¡æ, the carbon content in the steel should not be less than 0.04%. 304L stainless steel cannot be used at this time.
Huaxiao is one of 304 2b stainless steel sheet suppliers in China.
Therefore, it is wrong to think that 304L stainless steel products can be used in place of 304 stainless steel products. Whether it can be used is related to the occasion of use, and in accordance with the regulations, we have no right to “substitute materials”. Only the original design department can have the right to work on the “substitution of materials”. Please remember this!
We commonly use 304 stainless steel, and the processed stainless steel products can pass the 72-hour salt spray test.