Corten Steel Sheet Metal

When selecting Corten steel sheet metal, the choice between Corten A and Corten B depends on the application:

Choose Corten A for architectural, decorative, and landscaping uses where corrosion resistance and appearance are key
Choose Corten B for structural and heavy-duty applications requiring higher strength

Both grades provide the signature rusted patina and long-term durability, but their optimized properties make them suitable for different use scenarios.

Category: Corten Steel

Description

Corten steel sheet metal is commonly divided into two main grades: Corten A and Corten B. Both are weathering steels designed to form a protective rust layer, but they differ in composition, mechanical properties, and typical applications.

1. Chemical Composition Comparison

The main difference lies in alloying elements, especially phosphorus (P) and strength-related elements.

Element	Corten A (%)	Corten B (%)
Carbon (C)	≤ 0.12	≤ 0.19
Silicon (Si)	0.25 – 0.75	0.30 – 0.65
Manganese (Mn)	0.20 – 1.00	0.80 – 1.25
Phosphorus (P)	0.07 – 0.15	≤ 0.04
Sulfur (S)	≤ 0.03	≤ 0.03
Copper (Cu)	0.25 – 0.55	0.25 – 0.55
Chromium (Cr)	0.50 – 1.25	0.40 – 0.65
Nickel (Ni)	≤ 0.65	≤ 0.40

Key Insight

Corten A has higher phosphorus, improving atmospheric corrosion resistance
Corten B has lower phosphorus but higher strength-related elements

2. Mechanical Properties

Property	Corten A	Corten B
Yield strength	≥ 345 MPa	≥ 355 MPa
Tensile strength	480 – 630 MPa	490 – 630 MPa
Impact resistance	Limited specification	Better structural performance

3. Corrosion Resistance

Corten A:
- Better atmospheric corrosion resistance
- Ideal for decorative and architectural applications
Corten B:
- Slightly lower corrosion resistance than A
- Still excellent, but optimized for structural durability

4. Application Differences

Corten A (Weathering / Architectural Grade)

Facades and cladding
Garden planters and landscaping
Decorative panels and screens
Lightweight structures

Corten B (Structural Grade)

Bridges and heavy structures
Containers and industrial equipment
Railway wagons
Load-bearing outdoor structures

5. Key Differences Summary

Corrosion Resistance: Corten A > Corten B
Strength: Corten B > Corten A
Phosphorus Content: Higher in Corten A
Application Focus:
- A → aesthetics and weather resistance
- B → strength and structural use