Stainless steel is a versatile material widely used in various industries, from construction and transportation to food processing and medical equipment. One type of stainless steel gaining popularity due to its exceptional properties is 2507 stainless steel (SS).
It is a super duplex stainless steel with superior strength, stability against corrosion, and durability compared to other types of stainless steel.
In this article, we will go through SS 2507’s characteristics, feasibility, and uses in detail. Whether you are a manufacturer, engineer, or just someone interested in learning about new materials, this article will provide you with everything you need to know about this material.
What is 2507 SS?
2507 SS is a type of super duplex stainless steel that combines austenitic and ferritic stainless steel. It is also known as UNS S32750 or simply 2507 in the manufacturing industry.
This material has a high level of chromium, molybdenum, and nitrogen content which provides it with excellent resistance to corrosion, pitting, and crevice corrosion.
Its super duplex structure gives it higher strength and better stability against stress corrosion cracking than other stainless steel. It has good weldability and formability, too.
Physical Characteristics of 2507 Stainless Steel
As a super duplex stainless steel, 2507 possesses several exceptional properties. Some critical properties of 2507 stainless steel include high strength, excellent corrosion resistance, good weldability and formability, and outstanding resistance to pitting and crevice corrosion.
1. The Components and Microstructure of 2507 Stainless Steel
The composition of 2507 SS includes a combination of austenitic and ferritic stainless steel; it typically contains around 25% chromium, 7% nickel, 3.5% molybdenum, and 0.25% nitrogen, along with other elements such as copper and tungsten.
The microstructure of 2507 stainless steel consists of an equal mixture of austenite and ferrite, giving it its super duplex structure.
2. Corrosion Resistance Properties
The high nitrogen content in this stainless steel contributes to its superior corrosion- resistance. 2507 stainless steel is highly stable to corrosive forces, especially in harsh environments such as seawater and chloride-containing solutions.
It offers excellent protection against pitting and crevice corrosion, making it ideal for marine, chemical processing, and oil and gas industries.
3. Strength and Toughness
This stainless steel is a high-strength material that withstands extreme temperatures and pressures. It has excellent toughness and resistance to stress corrosion cracking, making it suitable for harsh environments.
Additionally, its super duplex structure provides higher strength and better resistance to fatigue than other types of stainless steel.
4. Weldability and Fabrication Properties
2507 stainless steel has good weldability and can be easily fabricated using standard techniques. However, it is essential to use low heat input during welding to avoid the formation of harmful intermetallic phases.
The material can be cut, formed, and shaped using standard fabrication techniques, and it can be easily machined using conventional methods.
5. Heat Resistance Properties
SS 2507 stainless steel has excellent heat resistance properties, making it suitable for high-temperature applications. It can withstand temperatures up to 600°C (1112°F) without degrading significantly or losing its mechanical properties.
6. Comparison with Other Stainless Steels
Compared to other grades, 2507 offers superior strength, chemical and structural stability, and durability.
- It is more stable against corrosion than 316L and provides enhanced stability against stress corrosion cracking than 904L.
- It has better weldability than 2205 duplex stainless steel, making it easier to fabricate and work with.
- Compared to 2205 duplex stainless steel, 2507 SS has better weldability, making it easier to fabricate and work with. Additionally, you can machine it conveniently using conventional methods.
- It also has better heat resistance properties than 316L stainless steel, making it suitable for high-temperature applications.
Applications and Uses of 2507 Stainless Steel
Here are the details of some applications of 2507 SS in various industries.
1. Oil and Gas Industry
The oil and gas industry demands materials that withstand harsh environments, including high pressures, temperatures, and corrosive fluids. SS 2507 is an ideal choice here because its strong and offers excellent resistance to corrosive forces.
It is commonly used in offshore platforms, pipelines, subsea equipment, umbilical lines, subsea manifolds, drill pipes, risers, and blowout preventers.
Compared to other types of stainless steel, such as 316L and 904L, it offers better resistance to pitting, crevice corrosion, and stress corrosion cracking.
These properties allow it to function efficiently in offshore environments exposed to saltwater, carbon dioxide, and hydrogen sulfide. Additionally, it can maintain its strength and toughness even at low temperatures, which makes it suitable for use in deepwater drilling applications.
2. Chemical Processing Industry
Materials used here are exposed to harsh, corrosive environments. SS 2507 is an ideal material for pressure vessels, reactors, heat exchangers, piping systems, and sulfuric acid production.
Its high corrosion resistance properties make it resistant to strong acids and bases, including sulfuric acid, hydrochloric acid, and sodium hydroxide.
It has excellent resistance to stress corrosion cracking and can maintain its strength and toughness at high temperatures, which makes it ideal for use in high-temperature and high-pressure applications.
3. Marine Industry
This material is utilized in the marine industry to withstand saltwater environments, extreme temperatures, and harsh weather conditions. It is used in propeller shafts, rudders, offshore mooring equipment, luxury yachts, cruise ships, handrails, lighting fixtures, and exhaust systems.
Compared to other types of stainless steel, 2507 has better corrosion resistance in seawater environments and can maintain its strength and toughness even at low temperatures. This makes it an ideal material for marine applications, as it can withstand exposure to saltwater and maintain its structural integrity over time.
4. Pulp and Paper Industry
This particular grade of stainless steel is used in the pulp and paper industry inside digesters, bleaching towers, pulp washers, blades, and knives for paper cutters and slicers.
Its high strength and toughness make it an ideal material for these applications, and its corrosion resistance makes it resistant to the harsh chemicals used in the manufacturing process.
Compared to other stainless steel grades, 2507 has better resistance to stress corrosion cracking, which makes it ideal for use in pulp and paper manufacturing environments where high levels of stress are typical.
2507 stainless steel can also maintain its strength and toughness at high temperatures.
5. Construction Industry
The superior strength and corrosion resistance of this stainless steel makes it a popular material for use in the construction industry. It is used to construct structural supports, roofing, and facades. It is also used to make components for chemical and marine environments.
In addition to roofing and structural supports, 2507 stainless steel is also used in building facades. The material’s unique aesthetic properties, including its ability to maintain its appearance over time, make it an excellent choice for high-end building facades.
Disadvantages of Using 2507 Stainless Steel
It is crucial to consider the potential disadvantages when deciding whether to use SS 2507 material for a particular application.
Cost, machinability, weldability, and availability should all be considered. Here are the details.
- Cost: This material is typically pricier than other stainless steels, such as 304 or 316, mainly due to its alloying elements and complicated manufacturing processes
- Machinability: Machining can be challenging and time-consuming due to its high strength and toughness.
Cutting and sawing, turning, drilling, milling, and grinding are all effective methods for machining this material, but they require careful attention to detail and a good understanding of its properties.
- Weldability: While 2507 stainless steel is generally considered good weldability, it can be more challenging to weld compared to other types of stainless steel. This is due to the high level of alloying elements in the material, which can affect the heat input required for welding and the formation of the weld.
- Availability: 2507 stainless steel may not be as readily available as other types of stainless steel, which can make it more challenging to source and may lead to longer lead times and higher costs.
Endnote
SS 2507 stainless steel is a durable and versatile material. Its exceptional corrosion resistance, high strength, toughness, heat resistance, and aesthetic appeal make it an ideal choice in various industries.
While it does have some potential disadvantages, such as lower machinability and higher cost compared to other stainless steel grades, the benefits of using this material often outweigh these drawbacks.
Overall, this grade of stainless steel is a high-performance material with exceptional durability, strength, and corrosion resistance for many years, making it an excellent choice for demanding applications.
If you’re considering investing in stainless steel products, 2507 SS should be on your radar.
Contact us today to learn more about 2507 stainless steel and order your sheets!
FAQs
1. How is 2507 Stainless Steel Manufactured?
The manufacturing process of 2507 stainless steel involves the following steps:
Step 1: Melting
The raw materials, such as iron, nickel, chromium, and molybdenum, are melted in an electric arc furnace or an induction furnace.
Step 2: Refining
The molten metal is then refined in a lathe furnace to remove its impurities.
Step 3: Casting
The refined metal is cast into ingots or billets of desired size and shape.
Step 4: Hot rolling
The ingots or billets are heated between 1150-1250°C and then hot rolled into bars or plates.
Step 5: Cold rolling
The hot-rolled bars or plates are cold-rolled to thin them to the desired dimensions.
Step 6: Heat Treatment
The final step is annealing the stainless steel at a high temperature (around 1050°C) to improve its mechanical properties and resistance to corrosion.
2. What are the environmental impacts of 2507 stainless steel?
On the positive side, SS 2507 is durable, long-lasting, and recyclable, which reduces the need for frequent replacement and waste.
However, its production requires a significant amount of water and energy and releases pollutants that contribute to climate change, air pollution, and water depletion.
3. What is the cost of 2507 stainless steel?
The cost of 2507 stainless steel can vary depending on several factors, such as market demand, quantity ordered, your supplier’s pricing policy, and the cost of raw materials. Currently, the cost of 2507 stainless steel is 7300 USD/Ton.
