Inquiry Now

ASME SA588 Grade B (SA588GRB) Weathering Steel Plate

Q: What is the service life of weathering steel?

Inland, dry environments: 50+ years (maintenance-free); industrial/suburban environments: 30–50 years; coastal areas with low salt spray: 15–25 years (additional corrosion protection required in areas with high salt spray).

Q: Can weathering steel be used in coastal areas or environments with high salt spray levels?

Use with caution. In environments with high salt spray levels or high chloride ion concentrations, the rust layer on standard weathering steel is easily penetrated, accelerating corrosion and potentially leading to pitting or perforation.

Q: What are the welding properties of weathering steel?

It has good welding properties and can be welded using conventional processes such as manual arc welding and gas shielded arc welding.

Q: Does weathering steel require painting?

In normal atmospheric conditions (urban or rural), painting is not required; a stable passivation layer will form after 6–18 months of exposure, providing a corrosion resistance lifespan of 80–100 years.High-humidity / highly corrosive environments (coastal areas, industrial acid rain, salt spray zones): It is recommended to apply a thin coat of weathering primer initially or to carry out regular maintenance to prevent the early loss of the rust layer.Concealed / damp, poorly ventilated areas: Waterproofing and anti-corrosion coating must be applied to prevent localised rusting from worsening.

Q: How long does it take for a rust layer (oxidation layer) to form on weathering steel?

The rate at which the oxidation layer forms depends on climatic conditions. In outdoor environments with significant fluctuations between dry and wet conditions, it typically takes between six months and two years for a stable, dark brown protective layer to form. During the initial stage, rust streaks may form, so care should be taken to protect the surrounding building surfaces.

ASME SA588 Grade B (SA588GRB) Weathering Steel Plate

info@yx-steel.com 8615837212056 Get a Quote

ASME SA588 Grade B (SA588GRB) is a high-strength low-alloy weathering steel (corten steel) standard from the American Society of Mechanical Engineers (ASME). Its core advantages include excellent atmospheric corrosion resistance, good weldability, and mechanical properties. It is widely used in outdoor structural components such as bridges, buildings, and towers, enabling long-term service without the need for complex anti-corrosion treatments.

Standard :
ASME SA588/SA588M
Grade :
SA588 Grade B (SA588GRB)
Thickness :
6.0 - 200.0 mm
Width :
1500.0 - 4050.0 mm
Length :
3000.0 - 15000.0 mm

Special thickness, width, and length can be negotiated separately.
We also provide customized processing services.If you have any questions, please contact us.

Overview

ASME SA588 Grade B (SA588GRB) is a high-performance structural steel plate that integrates high strength, excellent weathering resistance, and unique aesthetic value. It is an ideal choice for modern "maintenance-free" or "low-maintenance" steel structure designs, particularly in bridges and buildings. While ensuring structural safety, it significantly reduces lifecycle maintenance costs.

Grade	SA588 Grade B (SA588GRB)
Standard	ASME SA588/SA588M: High-strength low-alloy structural steel plate, sheet, and strip with atmospheric corrosion resistance
Delivery Conditions	Hot Rolled (HR), Normalized (N), Thermo-Mechanical Control Process (TMCP).
Core Features	Excellent atmospheric corrosion resistance (4 - 6 times higher than ordinary carbon steel).
Weldability	Good weldability, use low hydrogen welding processes and matching welding materials (such as the AWS E7018 series) to prevent weld cracking and maintain corrosion resistance in the weld area.
Machinability	It can be processed by conventional methods such as flame cutting, plasma cutting, cold bending, and drilling. Cold work formability is good.
Quality Control	Provide the material certificate. If required, Charpy V-notch impact test, and Z-direction property test (Grades Z15/Z25/Z35) can be added.
Application Scenarios	Bridges, building structures, towers, containers, outdoor mechanical components (requiring atmospheric corrosion resistance without the need for painting).

Key Features and Advantages

1. High Strength:

Minimum yield strength of 50 ksi (345 MPa) and minimum tensile strength of 70 ksi (485 MPa).

Under the same load conditions, compared to ordinary A36 steel (yield strength of 36 ksi), it allows for the use of less material, enabling lighter and more streamlined structural designs.

2. Excellent Weathering Resistance:

In rural, urban, and most industrial atmospheric environments, its corrosion resistance is 4 to 6 times that of ordinary carbon steel (such as A36).

This makes it highly suitable for painting-free structural applications, reducing long-term maintenance costs (no need for repeated painting) while offering a unique and aesthetically pleasing appearance.

3. Good Weldability and Workability:

It exhibits excellent weldability and can be processed using most common welding methods. However, attention must be paid to using matching welding materials and appropriate welding techniques to maintain the corrosion resistance of the welded areas.

Chemical Composition

Grade	SA588 Grade B (SA588GRB)
Element	C	Si	Mn	P	S	Ni	Cr	Cu	V	Mo	Nb
Content (max, %)	0.20	0.15 - 0.50	0.80 - 1.25	0.040	0.050	0.50	0.40 - 0.65	0.25 - 0.40	0.01 - 0.10	-	-

Carbon Equivalent: CEV ≤ 0.47%

Calculate using the International Institute of Welding (IIW) formula: CEV = C + Mn/6 + (Cr+Mo+V)/5 + (Ni+Cu)/15

Mechanical Properties

Grade	Thickness (t) [mm]	Tensile Strength [min, MPa]	Yield Point [min, MPa]	Elongation in 200mm [min, %]	Elongation in 50mm [min, %]
SA588 Grade B (SA588GRB)	t ≤ 100	485	345	18	21
	100 < t ≤ 125	460	315	-	21
	125 < t ≤ 200	435	290	-	21

Applications

Due to its high strength and excellent corrosion resistance, SA588 Grade B (SA588GRB) Weathering Steel Plate (Corten Steel Plate) is widely used in:

1. Bridge Structures: Box girders, trusses, bridge piers, pedestrian overpasses, etc., particularly for landscape bridges that aim for maintenance-free or low-maintenance solutions.

2. Building Structures: Exposed building frames, roof structures, building facades, decorative elements, etc. Its distinctive rust-colored appearance is highly favored by architects.

3. Transmission Towers and Steel Structures: Reduces maintenance requirements in highly corrosive environments.

4. Heavy Equipment and Machinery: Chemical equipment, port machinery, construction machinery, etc., where high strength and certain weather resistance are required.

5. Landscape Design: Outdoor art and sculptures, etc., utilizing the unique rust color to create aesthetic effects.

6. Others: Storage tanks, exhaust systems, marine facilities (additional anti-corrosion treatment required).

Other Information

Usage Precautions

1. Initial run-off rust: Before the rust layer stabilizes (typically requiring several wet-dry cycles, approximately 1-3 years), liquid containing rust may run off the steel surface, potentially staining surrounding walls, pavements, etc. Drainage or protective measures should be considered during design.

2. Unsuitable for specific environments: In persistently humid, high-salt (e.g., the spray zone of coastlines), or heavily chemically polluted environments, its weathering advantages may be significantly reduced, and protective coating may even be necessary.

3. Welding process: Low-hydrogen welding processes and compatible welding materials (such as the AWS E7018 series) must be used to prevent weld cracking and maintain the corrosion resistance of the welded area.

Comparison with Other ASME SA588/SA588M Grades

Feature	Grade A	Grade B	Grade C	Grade K
Core Features	Cost-effective weathering steel	Vanadium/Niobium micro-alloyed	Easy welding	High toughness, easy welding
Carbon Content	≤0.19%	≤0.20%	≤0.15%	≤0.17%
Key Elements	No V/Nb requirement	Contains V, (Nb)	Low C, Contains V, (Nb)	Low C, contains Mo and Nb
Strength Level	≥345 MPa	≥345 MPa	≥345 MPa	≥345 MPa
Toughness	Moderate	Good	Good	Excellent (especially at low temperatures)
Weldability	Good	Good	Excellent (low or no preheat required)	Excellent (low or no preheat required)
Main Applications	General weathering structures	Common bridges or buildings	Large bridges or buildings	Low-temperature, seismic, critical structures
Cost	Low	Medium	Medium	High

International Standard Equivalence

* Approximate correspondence, verification with specific technical requirements is necessary.

Standard	Grade	Difference Description
GB/T 4171 (China)	Q355NH	Corrosion resistance and mechanical properties are similar; Q355NH has a slightly lower carbon equivalent, offering better weldability.
EN 10025-5 (Europe)	S355J2W	Weathering grade corresponds; S355J2W has an impact test temperature of -20°C, consistent with SA588 Grade B.
JIS G 3114 (Japan)	SM490AW	Mechanical properties match; SM490AW has slightly lower corrosion-resistant element content, suitable for mild corrosive environments.
ASTM A588/A588M (USA)	A588 Grade B	Fully equivalent to ASME SA588 Grade B (ASME standard originates from ASTM, applicable for pressure equipment scenarios).

FAQ

Q1:

What is the service life of weathering steel?

Inland, dry environments: 50+ years (maintenance-free); industrial/suburban environments: 30–50 years; coastal areas with low salt spray: 15–25 years (additional corrosion protection required in areas with high salt spray).

Q2:

Can weathering steel be used in coastal areas or environments with high salt spray levels?

Use with caution. In environments with high salt spray levels or high chloride ion concentrations, the rust layer on standard weathering steel is easily penetrated, accelerating corrosion and potentially leading to pitting or perforation.

Q3:

What are the welding properties of weathering steel?

It has good welding properties and can be welded using conventional processes such as manual arc welding and gas shielded arc welding.

Q4:

Does weathering steel require painting?

In normal atmospheric conditions (urban or rural), painting is not required; a stable passivation layer will form after 6–18 months of exposure, providing a corrosion resistance lifespan of 80–100 years.

High-humidity / highly corrosive environments (coastal areas, industrial acid rain, salt spray zones): It is recommended to apply a thin coat of weathering primer initially or to carry out regular maintenance to prevent the early loss of the rust layer.

Concealed / damp, poorly ventilated areas: Waterproofing and anti-corrosion coating must be applied to prevent localised rusting from worsening.

Q5:

How long does it take for a rust layer (oxidation layer) to form on weathering steel?

The rate at which the oxidation layer forms depends on climatic conditions. In outdoor environments with significant fluctuations between dry and wet conditions, it typically takes between six months and two years for a stable, dark brown protective layer to form. During the initial stage, rust streaks may form, so care should be taken to protect the surrounding building surfaces.