A588 steel plate is a structural steel that Kloeckner Metals routinely stocks in coil, cut to length, hot rolled, and discrete formats nationwide.

Download Spec Sheet

Typical Standards

Sizes Routinely Stocked (Imperial)
FormatsThickness WidthLength
Coil3/16" - 1/2"48", 60", 72", 84", 96" Any
Cut to Length3/16" - 1/2"84", 96" Any
Hot Rolled (Strip Mill)3/16" - 1/2"48", 60", 72"Any
Discrete (Mill Rolled)48", 60", 72"96" 240" - 480"

General Info About A588 Steel

A588 is a high strength, low alloy steel plate that was developed for use cases demanding higher strength and a longer life cycle. A588 is known for its atmospheric corrosion resistance thanks to a natural patina of rust that forms when exposed to outdoor weather conditions.

More Details About A588 Steel

  • Advantages/Disadvantages

    The biggest advantage to A588 is its atmospheric corrosion resistance for which it was specially formulated. It is substantially better than other structural steels like A36 or A572.

  • Industries

    A588 steel was developed primarily for industries requiring outdoor structural steel solutions, wherever there is a need for a combination of lighter weight, higher durability, and exceptional corrosion resistance.

  • Applications

    You will primarily find A588 steel plate in welded bridges, buildings, and other structures.




  • Machining

    Grades A and B both have good material machinability.

  • Welding

    A588 welds similar to low carbon steels like ASTM A36 and ASTM A572. Due to A588’s specific coloring, you will need to consider color matching when welding.

Chemical Properties (Grade A)

0.19%0.80 - 1.25%0.030%0.030%0.03 - 0.65%0.40%0.40-0.65%0.25-0.40%0.02-0.10%

Chemical Properties (Grade B)

0.20%0.75 - 1.35%0.030%0.030%0.15 - 0.50%0.50%0.40-0.70%0.20-0.40%0.01-0.10%

Chemical Properties (Grade K)

0.17%0.50 - 1.20%0.030%0.030%0.25 - 0.50%0.40%0.40-0.70%0.10%0.30-0.50%0.005-0.05%

Mechanical Properties (Grade A)

Mechanical Properties
Tensile Strength, Ultimate400 - 550 MPa58,000 - 79,800 PSI
Tensile Strength, Yield250 MPa36,300 PSI
Elongation at Break (in 200 mm)20.0%20.0%
Elongation at Break (in 50 mm)23.0%23.0%
Modulus of Elasticity200 GPa29,000 KSI
Bulk Modulus (Typical for Steel)140 GPa20,300 KSI
Poissons Ratio0.2600.260
Shear Modulus79.3 GPa11,500 KSI

Frequently Asked Questions About A588

  • What grades is ASTM A588 available in?


    ASTM A588 is available in 3 grades, A, B, and K.

  • Is A588 weathering steel?


    With the addition of copper, nickel, and chromium alloys, ASTM A588 is specially designed for projects with high exposure to atmospheric conditions. In fact, its advantage over similar steels like A572 is its weathering ability. For that reason, A588 is also known as a weathering steel. The surface oxidation of weathering steel—what gives it its distinctive rusty appearance when unpainted—typically takes six months, but surface treatments can accelerate the oxidation to as little as a few hours.

  • Does A588 need to be painted?


    Because of its strong, innate resistance to corrosion, A588 can be used in its bare, or unpainted, condition.

  • How is A588 related to Cor-Ten®?


    Cor-Ten® is a trade name for atmospheric corrosion resistant steel with the same specifications as A588. As it became more popular over the years, mills began to develop their own versions, at which point ASTM created standard specifications for it, what we now know as A588.


Related Blog Posts

How to Calculate the Weight of a Steel Plate

To calculate the weight of a steel plate, you need to answer a few...

Read More

10 Questions to Ask a Structural Steel Fabricator

When starting a new commercial or residential project, you will want the right structural...

Read More

A Quick Guide to Annealing: What is Annealed Metal?

Annealing is a specific process of heat treatment that alters the properties of metal....

Read More

The 3 Stages of Heat Treatment

Overview of Heat Treatment  All of the typical processes performed on metals produce heat, whether it’s welding...

Read More

The 4 Types of Heat Treatment Steel Undergoes

In our last blog post, we covered the three stages of heat treatment that...

Read More

What’s the Difference Between ASTM A36 and ASME SA36?

The American Society for Testing and Materials (ASTM) A36 and the American Society for...

Read More

Additional Steel Plate Grades

ABS A and ABS B are types...
ABS A131 AH36 | DH36 | EH36 | FH36
Higher-strength ABS shipbuilding steel comes in six...
API 2H Grade 50
API 2H Grade 50 is a structural...
AR450 | AR450F
AR450, or AR450F steel, is a high-carbon...
AR400 | AR400F
AR400, or AR400F steel, is a high-carbon...
AR500 | AR500F
AR500, or AR500F steel, is a high-carbon...
A633 is high-strength low alloy structural steel...
A285 is a carbon steel intended for...
AR600 steel is a durable high-carbon alloy...
AR200 | AR225 | AR235 | AR Medium
AR200, AR225, and AR235, all under the...
MIL A 12560
MIL-A-12560 is a military spec armor steel...
UL NIJ Ballistic Tested Plate
Kloeckner Metals supplies UL NIJ Ballistic Tested...
MIL-A-46100 is a military spec armor steel...
A710 is a low-carbon, high-strength alloy steel...
A283 is a low carbon structural steel...
SA612 is a high strength carbon steel...
SA537 is a heat treated steel plate...
SA516 is the most popular pressure vessel...
1045 is a medium tensile steel that...
33 Max
33 Max is carbon plate that has...
Kloeckner Metals routinely stocks A656 in four...
A871-65 is an HSLA structural steel plate...
4140 steel is a chromium, molybdenum, manganese...
C1020—also called 1020 steel plate—is a low...
A709 is a high-strength, low-alloy steel plate...
A514 steel plate—also known as T1 steel—is...
A516 Grade 70
A516 is the most popular pressure vessel...
Kloeckner Metals routinely supplies A572, a high-strength,...
A36 steel is a staple in the...


Outdated or Unsupported Browser Detected

The Kloeckner Metals website uses modern technologies. Unfortunately, your browser doesn't support those technologies.

Download the latest version of one of these browsers to experience the site:

Do Not Remind Me Later