Stainless Steel Used in Industry - Which Grades Are Worth Choosing?
Stainless steel is a vital material in many industries due to its corrosion resistance, strength, and versatility. Choosing the right grade of stainless steel for industrial applications depends on several factors, including the specific requirements of the application, environmental conditions, and mechanical properties. Here are some of the most commonly used stainless steel grades in industry and their applications:
1. Austenitic Stainless Steels (300 Series)
304 stainless steel, also known as 18/8, is the most widely used austenitic stainless steel. It contains approximately 18% chromium and 8% nickel. This grade is highly resistant to corrosion and oxidation, making it ideal for a wide range of applications, including kitchen equipment, chemical processing, and food and beverage industry components. Its excellent formability and weldability are additional benefits.
316 stainless steel is similar to 304 but with an addition of 2-3% molybdenum. This enhancement improves corrosion resistance, especially against chlorides and other industrial solvents. It is commonly used in marine environments, pharmaceutical manufacturing, and medical devices. Its high resistance to pitting and crevice corrosion makes it suitable for harsh chemical environments.
2. Ferritic Stainless Steels (400 Series)
430 stainless steel contains 16-18% chromium and is known for its good corrosion resistance and formability. It is less expensive than 300 series Stainless Europe steels due to the absence of nickel. This grade is often used in automotive trim, kitchen appliances, and other household items. It is also magnetic, which can be a necessary property for certain applications.
3. Martensitic Stainless Steels (400 Series)
410 stainless steel contains about 11.5-13.5% chromium and offers a good balance of strength and moderate corrosion resistance. It can be heat-treated to enhance its hardness and is commonly used in cutlery, surgical instruments, and valves. While it is less corrosion-resistant than austenitic grades, its high strength and wear resistance are advantageous in applications requiring durability.
420 stainless steel is similar to 410 but with higher carbon content, which provides increased hardness and strength after heat treatment. It is widely used in applications like surgical instruments, knives, and dental tools.
4. Duplex Stainless Steels
2205 duplex stainless steel contains approximately 22% chromium, 5% nickel, and 3% molybdenum. It combines the best properties of austenitic and ferritic stainless steels, offering high strength, excellent corrosion resistance, and resistance to stress corrosion cracking. This grade is used in chemical processing, oil and gas industry, and marine applications.