Stainless steel is a popular finish for appliances, sinks, and kitchenware because of its durability, corrosion resistance, and sleek appearance. Two common types of stainless steel are 347 and 304, but what’s the difference between them? We’ll explore each type of stainless steel and its distinguishing factors.
Difference Between Stainless Steel 347 and 304
Chemical Composition
Stainless steel 304 is an austenitic alloy composed of nickel and chromium. It is the world’s most commonly used stainless steel and can withstand temperatures up to 800°C. Stainless steel 347 is a stabilized form of stainless steel 304 with the addition of niobium. This niobium addition helps to prevent chromium carbide precipitation that can occur during welding.
Weldability
Concerning welding, stainless steel 347’s addition of niobium also improves its weldability, compared to stainless steel 304. While both can be welded, 347 can be welded more easily without the risk of carbide precipitation. This makes 347 an ideal choice for high-temperature applications like jet engines.
Corrosion Resistance
Both stainless steels are highly corrosion resistant, but 347 can withstand more corrosive environments than 304. Its additional niobium content allows it to resist intergranular corrosion better than 304. 347 is commonly used in chemical processing and the petrochemical industry, where it can withstand high temperatures and corrosive environments.
Strength
Stainless steel 347 is stronger than 304 due to its higher nickel and chromium content. It’s also less ductile than 304, so it can’t be formed or shaped as easily. However, its higher strength makes it ideal for high-stress applications like pressure vessels and piping.
Cost
The cost of stainless steel can vary based on various factors, such as size, quantity, and unique features. Generally, 347 stainless steel is more expensive than 304 due to its higher nickel and chromium content. However, this can vary based on market demand and availability.
Conclusion:
Stainless steel 347 and 304 are both durable and corrosion-resistant alloys, but adding niobium sets aside 347 as a more weldable and corrosion-resistant alloy. On the other hand, the higher nickel and chromium content of 347 gives it better strength compared to 304. The choice between the two will depend on your application’s specific needs and requirements, while cost, availability, and fabricating requirements should also be considered. Knowing the differences between these alloys will ultimately lead to a more informed decision and a better outcome for your projects.
