Stainless Steel Grades Explained: 304, 316, and Beyond
Stainless Steel Grades Explained
Stainless steel comes in numerous grades, each designed for specific applications. Understanding these grades helps you select the right material for your project.
What Makes Steel "Stainless"?
Stainless steel contains at least 10.5% chromium, which forms a protective oxide layer that resists corrosion. Additional elements enhance specific properties.
Grade 304 (18/8)
Composition: 18% chromium, 8% nickel
Properties:
- Excellent corrosion resistance
- Good formability
- Weldable
- Non-magnetic (annealed)
Applications:
- Kitchen equipment
- Food processing
- Architectural trim
- Chemical containers
Grade 316 (Marine Grade)
Composition: 16% chromium, 10% nickel, 2% molybdenum
Properties:
- Superior corrosion resistance
- Excellent for marine environments
- Resistant to chlorides
- Higher cost than 304
Applications:
- Marine hardware
- Medical devices
- Chemical processing
- Coastal construction
Grade 430 (Ferritic)
Properties:
- Lower cost
- Magnetic
- Good formability
- Less corrosion resistant
Applications:
- Automotive trim
- Appliance panels
- Indoor applications
Grade 2205 (Duplex)
Properties:
- High strength
- Excellent corrosion resistance
- Good weldability
Applications:
- Oil and gas industry
- Pressure vessels
- Marine structures
Selection Guide
Choose 304 for general purpose, 316 for marine/chemical exposure, 430 for cost-sensitive indoor use.