ASTM A240 Standard Specification for Chromium and Chromium-Nickel Stainless Steel Plate, Sheet, and Strip for Pressure Vessels and General Applications

ASTM A240 is the standard specification covering chromium and chromium-nickel stainless steel plate, sheet, and strip intended for pressure vessels and general applications.

It is one of the most widely referenced stainless steel material standards for industrial fabrication, petrochemical equipment, pressure vessels, storage tanks, structural components, and general corrosion-resistant applications.

ASTM A240 defines chemical composition limits, mechanical property requirements, heat treatment conditions, surface finish classifications, dimensional tolerances, and inspection standards.


What Is ASTM A240?

ASTM A240 is issued by ASTM International and applies to flat-rolled stainless steel products, including:

  • Plate

  • Sheet

  • Strip

The specification establishes requirements for:

  • Chemical composition

  • Mechanical properties

  • Heat treatment

  • Surface finish

  • Testing and certification

Unlike ASTM A312 (pipe) and ASTM A213 (tube), ASTM A240 applies to flat products used for fabrication and pressure-retaining components.


Scope of ASTM A240

ASTM A240 covers stainless steel materials intended for:

  • Pressure vessels

  • Storage tanks

  • Structural components

  • Industrial fabrication

  • Corrosion-resistant equipment

It includes both:

  • Austenitic stainless steels

  • Ferritic stainless steels

  • Martensitic stainless steels

  • Duplex stainless steels

The standard focuses on material properties prior to fabrication.


Product Forms Covered

ASTM A240 applies to:

Stainless Steel Plate

Typically thicker materials used in pressure vessels and heavy fabrication.

Stainless Steel Sheet

Thinner flat products used in industrial and architectural applications.

Stainless Steel Strip

Narrow-width products for specialized manufacturing.

Dimensional tolerances for flat products are often governed by ASTM A480/A480M.


Grades Covered Under ASTM A240

ASTM A240 includes a wide range of stainless steel grades.

Austenitic Grades

  • Type 304 / 304L

  • Type 316 / 316L

  • Type 321

  • Type 347

These grades provide excellent corrosion resistance and formability.

Ferritic Grades

  • Type 409

  • Type 430

Used in moderate corrosion environments and automotive applications.

Martensitic Grades

  • Type 410

  • Type 420

Heat-treatable grades offering higher strength and hardness.

Duplex Grades

  • UNS S31803 / S32205 (2205)

  • UNS S32750 (2507)

Provide high strength and superior resistance to chloride corrosion.


Chemical Composition Overview

Type 304

  • Chromium (Cr): 18–20%

  • Nickel (Ni): 8–11%

  • Carbon (C): ≤ 0.08%

Type 316

  • Chromium (Cr): 16–18%

  • Nickel (Ni): 10–14%

  • Molybdenum (Mo): 2–3%

Duplex 2205

  • Chromium (Cr): 22–23%

  • Nickel (Ni): 4.5–6.5%

  • Molybdenum (Mo): 3–3.5%

Exact chemical limits must comply with the latest ASTM A240 edition.

Grade UNS C Mn P S Si Cr Ni Mo N Cu Other/Notes
304 S30400 0.08 2.00 0.045 0.030 0.75 18.0–20.0 8.0–11.0 0.10
316 S31600 0.08 2.00 0.045 0.030 0.75 16.0–18.0 10.0–14.0 2.00–3.00 0.10
321 S32100 0.08 2.00 0.045 0.030 0.75 17.0–19.0 9.0–12.0 0.10 Ti 5×(C+N) min, 0.70 max
347 S34700 0.08 2.00 0.045 0.030 0.75 17.0–19.0 9.0–13.0 Nb 10×C min, 1.00 max
309S S30908 0.08 2.00 0.045 0.030 0.75 22.0–24.0 12.0–15.0
310S S31008 0.08 2.00 0.045 0.030 1.50 24.0–26.0 19.0–22.0
430 S43000 0.12 1.00 0.040 0.030 1.00 16.0–18.0 0.75
410 S41000 0.08–0.15 1.00 0.040 0.030 1.00 11.5–13.5 0.75
31803 S31803 0.030 2.00 0.030 0.020 1.00 21.0–23.0 4.5–6.5 2.5–3.5 0.08–0.20
32205 S32205 0.030 2.00 0.030 0.020 1.00 22.0–23.0 4.5–6.5 3.0–3.5 0.14–0.20
32750 S32750 0.030 1.20 0.035 0.020 0.80 24.0–26.0 6.0–8.0 3.0–5.0 0.24–0.32 0.50 max
32760 S32760 0.030 1.00 0.030 0.010 1.00 24.0–26.0 6.0–8.0 3.0–4.0 0.20–0.30 0.50–1.00 W 0.50–1.00

Mechanical Property Requirements

ASTM A240 specifies minimum mechanical properties including:

  • Tensile strength

  • Yield strength

  • Elongation

For example:

Type 304 plate typically requires:

  • Tensile strength ≥ 515 MPa

  • Yield strength ≥ 205 MPa

Duplex grades provide significantly higher yield strength compared to austenitic grades.

Mechanical values may vary depending on thickness and heat treatment condition.


Heat Treatment Requirements

Flat-rolled stainless steel products under ASTM A240 are typically supplied in the annealed condition.

Heat treatment ensures:

  • Proper microstructure

  • Corrosion resistance

  • Adequate ductility

  • Dimensional stability

For martensitic grades, additional hardening and tempering may be applied depending on application requirements.


Surface Finish Classifications

ASTM A240 products may be supplied with different surface finishes, including:

  • No.1 (Hot-rolled, annealed, descaled)

  • 2B (Cold-rolled, annealed, pickled)

  • BA (Bright annealed)

  • Polished finishes

Surface finish selection depends on fabrication and application requirements.


Testing and Inspection Requirements

ASTM A240 requires:

  • Tension test

  • Hardness testing (where applicable)

  • Dimensional inspection

  • Surface quality inspection

Material Test Certificates are typically provided according to EN 10204 3.1 or 3.2.


ASTM A240 vs ASTM A480

Feature ASTM A240 ASTM A480
Focus Material specification General requirements & tolerances
Product Plate, sheet, strip Flat-rolled stainless steel
Role Defines grades & properties Defines tolerances & general requirements

ASTM A480 is commonly referenced alongside ASTM A240.


ASTM A240 vs ASTM A312

Feature ASTM A240 ASTM A312
Product Form Plate / Sheet Pipe
Application Fabrication Pressure piping
Dimension Standard Thickness & width NPS & Schedule

Typical Applications of ASTM A240 Material

  • Pressure vessels

  • Storage tanks

  • Chemical processing equipment

  • Industrial fabrication

  • Structural components

  • Architectural applications

ASTM A240 stainless steel is widely selected where corrosion resistance and formability are required.


Frequently Asked Questions

What is the difference between ASTM A240 and A480?

ASTM A240 defines material grades and properties, while ASTM A480 covers general requirements and tolerances for flat-rolled stainless steel.

Does ASTM A240 include 304 and 316?

Yes, 304 and 316 are among the most commonly specified grades under ASTM A240.

Is ASTM A240 used for pressure vessels?

Yes, it is widely used for pressure vessel fabrication.

Does ASTM A240 include duplex stainless steel?

Yes, duplex grades such as 2205 and 2507 are included.


Download ASTM A240 Standard Specification (Reference PDF)

A reference overview PDF is available below.

For the official and latest complete standard, please refer to ASTM International.

[Download ASTM A240 PDF]

Related Products

ASTM A240 304L Plate

ASTM A240 316L Plate

ASTM A240 321 Sheet

ASTM A240 UNS S31803 Plate

ASTM A240 UNS S32750 Plate