Stainless Steel 300 vs 400 – What’s the Difference?

In our daily lives, stainless steel stands out as a unique material, renowned for its durability, corrosion resistance, and versatility. Within this vast category, two families of stainless steel are particularly noteworthy: the 300 series and the 400 series. While both offer excellent properties, there exist significant differences between them. So, stainless steel 300 vs 400 – what’s the difference? In this article, we delve into the distinct features of stainless steel 300 and 400 series to provide a comprehensive understanding of their differences.

Stainless Steel 300 vs 400 – What’s the Difference?

Stainless Steel 300 vs 400 – 1. Composition

The fundamental difference between the 300 and 400 series of stainless steel lies in their alloy composition. The 300 series, also known as austenitic stainless steel, is primarily composed of iron, chromium (at least 18%), and nickel (typically 8-10%). The addition of nickel is crucial, as it stabilizes the austenitic structure, ensuring ductility and corrosion resistance even at elevated temperatures.

On the other hand, the 400 series, or ferritic stainless steel, contains iron, chromium (at least 12%), and possibly other elements like carbon, silicon, and manganese. This series lacks the nickel content, which gives the 300 series its unique properties. Instead, the 400 series relies on chromium for corrosion resistance, forming a protective oxide layer on the surface.

Stainless Steel 300 vs 400 – 2. Properties

The compositional differences lead to distinct properties in the 300 and 400 series. Austenitic stainless steel (300 series) is known for its exceptional ductility, toughness, weldability, and corrosion resistance. The high nickel content ensures good resistance to chloride-induced corrosion, making it suitable for marine and chemical processing applications. Additionally, the 300 series offers good magnetic properties, with some grades being partially or fully magnetic.

In contrast, ferritic stainless steel (400 series) exhibits higher strength and hardness compared to the 300 series. It is less ductile and more brittle, but still maintains good corrosion resistance, especially in oxidizing environments. The absence of nickel in the 400 series makes it more cost-effective than the 300 series, but it also reduces its resistance to chloride-induced corrosion. This series is typically non-magnetic, with some exceptions.

Stainless Steel 300 vs 400 – 3. Applications

The unique properties of the 300 and 400 series stainless steel make them suitable for different applications. The 300 series, with its excellent corrosion resistance and ductility, is widely used in the construction of kitchen appliances, surgical instruments, chemical processing equipment, and marine components. It is also commonly found in architectural applications like railings and cladding.

The 400 series, on the other hand, finds its primary applications in automotive components, kitchenware, and other structural applications where cost is a key factor. Its higher strength and resistance to oxidizing environments make it suitable for automotive exhaust systems and other components exposed to high temperatures. Additionally, the 400 series is often used in knife blades and surgical instruments due to its hardness and edge retention.

Conclusion

In summary, the 300 and 400 series of stainless steel differ significantly in composition, properties, and applications. The 300 series, with its high nickel content, offers excellent corrosion resistance, ductility, and weldability, making it suitable for demanding applications in various industries. The 400 series, with its higher strength and cost-effectivenesss, finds applications in structural components and other areas where corrosion resistance is less critical. 

Thank you for reading our article and we hope it can help you to have a better understanding of the differences between Stainless Steel 300 vs 400. If you are looking for Stainless Steel 300 and 400 products suppliers online now, please don’t hesitate to contact Sino Stainless Steel.

As a leading supplier of stainless steel products from Shanghai China, Sino Stainless Steel provides customers with high-quality stainless steel sheets, stainless steel tubes, stainless steel pipes, stainless steel strips, stainless steel coils, stainless steel plates, and stainless steel bars at a very competitive price.