🟧 Product Overview

ASTM A242 / Q295NH / Q355NH represents the low‑alloy weathering steel family, widely used for architectural, structural, and outdoor applications requiring long‑term corrosion resistance.

• ASTM A242 – Classic Corten A type weathering steel
• Q295NH / Q355NH – Chinese GB/T 4171 atmospheric corrosion resistant structural steels
• Performance – Excellent patina formation, stable corrosion resistance, and good weldability

This series is especially suitable for architectural façades, containers, bridges, and outdoor structures where aesthetic patina and durability are required.

🟧 Standards

• ASTM A242 – High‑Strength Low‑Alloy Structural Steel
• GB/T 4171 – Atmospheric Corrosion Resistant Structural Steel
• EN 10025‑5 (reference) – Weathering structural steels

🟧 International Weathering Steel Comparison Table

Country	Standard	Common Grades
America	ASTM A242	A242 Type 1
Europe	EN 10025‑5	S355J0W, S355J2W
China	GB/T 4171	Q295NH, Q355NH, Q355GNH
Japan	JIS G3125	SPA‑H
International	Corten Steel	Corten A, Corten B

🟧 Available Grades

• ASTM A242
• Q295NH
• Q355NH

🟧 Product Specifications & Available Sizes

Dimensions

• Thickness: 1.5 – 20 mm
• Width: 1000 – 2000 mm
• Coil ID: 508 mm / 610 mm
• Coil OD: 900 – 2000 mm
• Coil Weight: 3 – 15 MT

Regular Sizes (mm)

Size	Size
1.5 × 1250 × C	3.0 × 1500 × C
2.0 × 1250 × C	4.0 × 1500 × C
2.5 × 1500 × C	5.0 × 1500 × C

🟧 Chemical Composition (A242 / Q295NH / Q355NH – typical)

Element	Range (%)
C	≤ 0.12
Mn	0.20 – 1.60
P	0.035 – 0.150
S	≤ 0.030
Si	0.25 – 0.75
Cu	0.20 – 0.50
Cr	0.40 – 1.25
Ni	0.20 – 0.65

🟧 Mechanical Properties (A242 / Q355NH – typical)

Property	Value
Yield Strength	295–355 MPa
Tensile Strength	440–630 MPa
Elongation	≥ 20%
Atmospheric Corrosion Resistance	2–8× carbon steel
Patina Formation	Stable, protective oxide layer

🟧 Physical Properties

• Density: 7.85 g/cm³
• Modulus of elasticity: 210 GPa
• Thermal expansion: 12×10⁻⁶ /K

🟧 Manufacturing Processes

• Hot rolling
• Normalizing (optional)
• Pickling
• Leveling
• Slitting / Cutting to length
• Surface oiling

🟧 Primary Industry Usage

• Architectural façades and decorative panels
• Shipping containers
• Bridges and structural components
• Outdoor sculptures and landscape structures
• Railway vehicles
• Weather‑resistant building panels

🟧 Why Use A242 / Q295NH / Q355NH Weathering Steel Coil

• Strong atmospheric corrosion resistance
• Stable patina layer reduces maintenance
• Good weldability and processing performance
• Cost‑effective alternative to A588 series
• Suitable for both structural and architectural applications

🟧 Why Choose WelSteels

• Full range of international weathering steel coils
• Stable mechanical and corrosion‑resistant performance
• Custom coil cutting and slitting
• SGS / BV inspection available
• Export‑grade seaworthy packaging
• Reliable delivery for global projects