Return To posts

Guide to Stainless Steel Grades

Guide to Stainless Steel Grades

Guide to Stainless Steel Grades

Stainless steel is one of the world’s most popular metals. This substance possesses visual and chemical advantages that manufacturers use for countless industrial and consumer products.

What Is Stainless Steel?

Stainless steel is an alloy of iron, carbon and chromium. Though all stainless steel comprises at least 10.5% chromium, other ratios depend on its grade and application purposes. The chromium content protects the metal’s surface by preventing air and moisture contact, which causes rust and corrosion.

You can add other elements to stainless steel to further enhance its corrosion resistance, temperature endurance, formability, strength and weldability. Common additives include alloys like nickel, manganese, nitrogen, copper, molybdenum, sulfur and silicon.

Types of Stainless Steel

There are various classifications of stainless steel that manufacturers can choose from to achieve specific functions. There are over a hundred different stainless steel grades that fall within four primary categories.

200-300 Series Austenitic Stainless Steel

Austenitic stainless steel is the most common type. This metal comprises a high chromium and nickel content, giving it excellent surface quality and corrosion and heat resistance. 

Austenitic stainless steel is highly malleable, easy to weld and typically more expensive than other stainless steel grades. Though austenitic steel is nonmagnetic when annealed, it can be become magnetic when cold worked, depending on its nickel content and composition.

Numerous applications use austenitic stainless steel, including:

 

  • Houseware.
  • Industrial piping.
  • Automotive components.
  • Cookware.
  • Sanitary applications.
  • Aircraft fittings.
  • Architecture.
  • Food processing.

 

400 Series Ferritic Stainless Steel

Ferritic stainless steels are magnetic substances with high chromium and low carbon compositions, which prevent corrosion, cracking and scaling at high temperatures. Ferritic steel is useful for products that are frequently exposed to corrosive materials. Due to their low nickel content, ferritic materials are less expensive than other stainless steels.

 Some of the many ferritic stainless steel applications include:

 

  • Washing machines.
  • Boilers.
  • Indoor architecture.
  • Automotive components and systems.
  • Cookware.
  • Caskets.
  • Refrigerator doors.
  • Bolts, nuts and screws.

 

400 Series Martensitic Stainless Steel

Martensitic steel is among the lesser-known types of stainless steel. This grade has a similar chromium level to ferritic stainless steel with a higher carbon content for increased strength, hardness and heat resistance. This magnetic steel is more challenging to weld and has a lower corrosion resistance than other materials.

Common uses for martensitic stainless steel include:

 

  • Knives.
  • Turbine parts.
  • Cutlery.
  • Hospital equipment.
  • Pump and boat shafts.
  • Marine hardware.
  • Ball bearings.
  • Mine ladder rungs.

 

Duplex Stainless Steel

Duplex is a recently discovered stainless steel that combines austenitic and ferritic steel. It claims advantages of both grades, including high strength, flexibility and cracking, bending and corrosion resistance. Duplex stainless steel is stronger than its austenitic and ferritic counterparts and is well-suited for forming and welding.

Duplex stainless steel is often used in the following industries:

 

  • Paper
  • Shipbuilding
  • Petrochemical
  • Pulp
  • Marine
  • Chemical
  • Underwater oil

 

Partner With a Full-Service Metal Manufacturing Company Today

Reach out to PBZ Manufacturing with your questions about stainless steel and your project. As Pennsylvania’s one-stop shop for metal manufacturing, we have comprehensive capabilities to take any project from planning to completion.

Leave us a message today to get started with our services!

Contact us and put our resourcefulness to work for you.
You'll hear back from us within 4 business hours.

Stay Connected.

Join our email list for our latest news and updates!