Composition and Properties of 321 Stainless Steel

When we talk about stainless steel, 321 stainless steel is one of the most eye-catching varieties. This material is favored by various industries because of its unique chemical composition and excellent performance. Today, let’s uncover the mystery of 321 stainless steel together, learn more about the composition and properties of 321 stainless steel, and see why it stands out among many stainless steel.

What is the chemical composition of 321 stainless steel?

The main chemical components of 321 stainless steel include:

1. Iron (Fe): About 60-75% of the total mass of the alloy.
2. Nickel (Ni): Approximately 8-11%. Improves the corrosion resistance of the alloy.
3. Chromium (Cr): Approximately 17-20%. Increases the hardness, wear resistance, and corrosion resistance of the alloy.
4. Manganese (Mn): about 2%. Improves the strength and toughness of the alloy.
5. Silicon (Si): about 1%. It has an impact on the cold workability of the alloy.
6. Carbon (C): limited to less than 0.08%. The hardness and strength of the alloy are controlled.
7. Phosphorus (P) and sulfur (S): Both are limited to low levels to avoid negative effects on the corrosion and mechanical properties of the alloy.

These chemical components work together to let 321 stainless steel have good corrosion resistance, heat resistance, mechanical strength, and good welding performance.

What are the mechanical properties of 321 stainless steel?

321 stainless steel is a high-strength and corrosion-resistant stainless steel. It has excellent mechanical properties, mainly including the following aspects:

1. Tensile strength: At room temperature, the tensile strength of 321 stainless steel is about 515MPa.
2. Yield strength: At room temperature, the yield strength of 321 stainless steel is about 205MPa.
3. Elongation: The elongation of 321 stainless steel is about 40%, indicating its good ductility.
4. Hardness: The hardness of 321 stainless steel is about HB217.

It should be noted that the mechanical properties of 321 stainless steel will change with the influence of processing methods, heat treatment, and other factors.

What are the physical properties of 321 stainless steel?

321 stainless steel has good physical properties, which are mainly as follows:

1. Density: The density of 321 stainless steel is about 7.93g/cm³.
2. Melting point: The melting point of 321 stainless steel is about 1398℃.
3. Thermal conductivity: The thermal conductivity of 321 stainless steel is about 16.2 W/(m.K) at room temperature.
4. Thermal expansion coefficient: The linear expansion coefficient of 321 stainless steel is about 16.5×10^-6 /K.
5. Magnetism: 321 stainless steel is a non-magnetic material and will not generate magnetism in a magnetic field.

It should be noted that the physical properties of 321 stainless steel will also change with the influence of material status, processing methods, and other factors.

Applications of 321 Stainless Steel

321 stainless steel is mainly used in outdoor machinery for the chemical, coal, and petroleum industries with high requirements for resistance to grain boundary corrosion, heat-resistant parts for building materials, and parts that have difficulty in heat treatment, such as:

1. Petroleum waste gas combustion pipeline
2. Engine exhaust pipe
3. Boiler shell, heat exchanger, heating furnace components
4. Diesel engine silencing components
5. Boiler pressure vessel
6. Chemical transport vehicle
7. Expansion joint
8. Spiral welded pipe for furnace pipes and dryers
9. Aircraft

Conclusion

Thank you for reading our article and we hope it can help you to have a better understanding of the composition and properties of 321 stainless steel. If you want to learn more about 321 Stainless Steel, we’d advise you to visit Sino Stainless Steel for more information.

As a leading supplier of stainless steel products across the world, Sino Stainless Steel offers customers high-quality stainless steel products such as 321 Hot-rolled Stainless Steel Plate,  Stainless Steel Angles, Stainless Steel Channels, 201 Stainless Steel Strips & 304 Stainless Steel Strips, 430 Stainless Steel Plates, Stainless Steel Hexagon Bars, Hot-rolled Stainless Steel, Colored Stainless Steel Sheets, Cold-rolled Precision Stainless Steel, Stainless Steel Wire, and Embossed Stainless Steel Plates.