ASTM A240/A240M is the internationally recognized standard specification published by ASTM International, covering chromium, chromium-nickel, and chromium-manganese-nickel stainless steel plate, sheet, and strip for pressure vessels and general applications. The companion specification ASME SA-240 adopts identical technical requirements for ASME Boiler and Pressure Vessel Code (BPVC) compliance.
HT PIPE supplies ASTM A240 / SA-240 compliant flat products across austenitic, ferritic, martensitic, and duplex grades, with full Mill Test Certificates (MTC) per EN 10204 3.1.
1. Standard Scope & Designation
ASTM A240/A240M covers flat-rolled stainless steel in three product forms:
| Form |
Thickness |
Width |
Notes |
| Plate |
≥ 5 mm (3/16 in.) |
≥ 250 mm (10 in.) |
Hot-rolled or cold-rolled, ≥ 5 mm thick |
| Sheet |
< 5 mm (3/16 in.) |
≥ 600 mm (24 in.) |
Cold-rolled typical; widths ≥ 600 mm |
| Strip |
< 5 mm (3/16 in.) |
< 600 mm (24 in.) |
Slit from coil or direct rolled; narrow widths |
Scope Statement (ASTM A240-24a): "This specification covers chromium, chromium-nickel, and chromium-manganese-nickel stainless steel plate, sheet, and strip for pressure vessels and for general applications. The steel is to conform to the requirements specified in this specification and to those in Specification A480/A480M."
| Designation |
Issuing Body |
Unit System |
Primary Application |
Latest Edition |
| ASTM A240 |
ASTM International |
Inch-Pound |
General industrial, pressure vessels |
A240/A240M-24a |
| ASTM A240M |
ASTM International |
SI (Metric) |
General industrial, pressure vessels |
A240/A240M-24a |
| ASME SA-240 |
ASME (BPVC Sec. II Part A) |
Both |
ASME Code pressure vessels & boilers |
2023 Edition |
| EN 10028-7 |
CEN (Europe) |
SI |
Pressure vessel flat products (EU equivalent) |
EN 10028-7:2016 |
2. Stainless Steel Grades Covered
ASTM A240 covers more than 40 stainless steel grades organized into four metallurgical families:
2.1 Austenitic Grades (300 Series & High-Alloy)
| Grade / Type |
UNS No. |
Key Alloying Feature |
Typical Application |
| 304 / 304L / 304H |
S30400 / S30403 / S30409 |
18Cr-8Ni / Low C / High C |
General industry, food, chemical |
| 316 / 316L / 316H / 316Ti |
S31600 / S31603 / S31609 / S31635 |
16Cr-10Ni-2Mo; Mo variants |
Marine, pharma, chemical process |
| 317 / 317L |
S31700 / S31703 |
18Cr-11Ni-3Mo |
Pulp & paper, FGD systems |
| 321 / 321H |
S32100 / S32109 |
Ti-stabilized |
High-temperature service, exhaust |
| 347 / 347H |
S34700 / S34709 |
Nb+Ta-stabilized |
High-temp pressure vessels, aerospace |
| 310 / 310S / 310H |
S31000 / S31008 / S31009 |
25Cr-20Ni, heat resisting |
Furnace parts, heat exchangers |
| 904L |
N08904 |
20Cr-25Ni-4Mo-1.5Cu |
H₂SO₄ environments, offshore |
| 254 SMO |
S31254 |
20Cr-18Ni-6Mo (6% Mo) |
Seawater, bleach, chloride-rich media |
2.2 Ferritic Grades
| Grade |
UNS No. |
Cr Content |
Typical Application |
| 409 |
S40900 |
10.5–11.75% |
Automotive exhaust, mufflers |
| 430 |
S43000 |
16–18% |
Automotive trim, kitchen equipment |
| 439 |
S43035 |
17.0–19.0% |
Hot water tanks, solar heaters |
| 444 |
S44400 |
17.5–19.5% |
Water heaters, food processing |
| 446 |
S44600 |
23–27% |
High-temp oxidation resistance |
2.3 Martensitic Grades
| Grade / Type |
UNS No. |
C Content |
Typical Application |
| 403 |
S40300 |
≤0.15% |
Turbine blades, compressor parts |
| 410 / 410S |
S41000 / S41008 |
≤0.15% / ≤0.08% |
Cutlery, pump shafts, valves |
| 420 |
S42000 |
0.15–0.45% |
Surgical instruments, knife blades |
| 440A / 440C |
S44002 / S44004 |
0.60–0.75% / 0.95–1.20% |
Bearings, nozzles, high-hardness parts |
2.4 Duplex & Super-Duplex Grades
| Grade / Designation |
UNS No. |
PREN* |
Typical Application |
| 2205 (Duplex) |
S31803 / S32205 |
~35 |
Oil & gas, chemical, desalination |
| 2507 (Super Duplex) |
S32750 |
~43 |
Offshore, subsea, seawater injection |
| Zeron 100 (Super Duplex) |
S32760 |
~41 |
High-chloride environments |
| LDX 2101 (Lean Duplex) |
S32101 |
~26 |
Storage tanks, structural |
*PREN = %Cr + 3.3×%Mo + 16×%N (Pitting Resistance Equivalent Number)
3. Chemical Composition — Key Grades (ASTM A240 / A240M-24a, Table 1)
Values are maximum unless shown as a range. "—" = not required / not applicable.
| Grade |
C % |
Mn % |
Si % |
P % |
S % |
Cr % |
Ni % |
Mo % |
N % |
Other |
| 304 |
0.07 |
2.00 |
0.75 |
0.045 |
0.030 |
17.5–19.5 |
8.0–10.5 |
— |
0.10 |
— |
| 304L |
0.030 |
2.00 |
0.75 |
0.045 |
0.030 |
17.5–19.5 |
8.0–12.0 |
— |
0.10 |
— |
| 304H |
0.04–0.10 |
2.00 |
0.75 |
0.045 |
0.030 |
18.0–20.0 |
8.0–10.5 |
— |
— |
— |
| 316 |
0.07 |
2.00 |
0.75 |
0.045 |
0.030 |
16.0–18.0 |
10.0–14.0 |
2.00–3.00 |
0.10 |
— |
| 316L |
0.030 |
2.00 |
0.75 |
0.045 |
0.030 |
16.0–18.0 |
10.0–14.0 |
2.00–3.00 |
0.10 |
— |
| 316H |
0.04–0.10 |
2.00 |
0.75 |
0.045 |
0.030 |
16.0–18.0 |
10.0–14.0 |
2.00–3.00 |
— |
— |
| 321 |
0.08 |
2.00 |
0.75 |
0.045 |
0.030 |
17.0–19.0 |
9.0–12.0 |
— |
0.10 |
Ti: 5×C–0.70 |
| 347 |
0.08 |
2.00 |
0.75 |
0.045 |
0.030 |
17.0–19.0 |
9.0–13.0 |
— |
— |
Nb+Ta: 10×C–1.00 |
| 310S |
0.08 |
2.00 |
1.50 |
0.045 |
0.030 |
24.0–26.0 |
19.0–22.0 |
— |
— |
— |
| 904L |
0.020 |
2.00 |
1.00 |
0.040 |
0.030 |
19.0–23.0 |
23.0–28.0 |
4.0–5.0 |
0.10 |
Cu: 1.0–2.0 |
| 410 |
0.15 |
1.00 |
1.00 |
0.040 |
0.030 |
11.5–13.5 |
0.75 |
— |
— |
— |
| 430 |
0.12 |
1.00 |
1.00 |
0.040 |
0.030 |
16.0–18.0 |
0.75 |
— |
— |
— |
| 2205 |
0.030 |
2.00 |
1.00 |
0.030 |
0.020 |
22.0–23.0 |
4.5–6.5 |
3.0–3.5 |
0.14–0.20 |
— |
| 2507 |
0.030 |
1.20 |
0.80 |
0.035 |
0.020 |
24.0–26.0 |
6.0–8.0 |
3.0–5.0 |
0.24–0.32 |
— |
Note: Product analysis limits per ASTM A240 Table 1. Heat analysis limits may differ slightly. Full product analysis ranges and additional grades in the official ASTM A240-24a standard.
4. Mechanical Property Requirements (ASTM A240 Table 2)
All values are minimum requirements in the annealed condition. Per ASTM A240/A240M-24a.
| Grade |
UNS |
Tensile Strength min
MPa (ksi) |
Yield Strength 0.2%
min MPa (ksi) |
Elongation
min % |
Hardness max
HRB / HBW |
| 304 |
S30400 |
515 (75) |
205 (30) |
40 |
92 / 200 |
| 304L |
S30403 |
485 (70) |
170 (25) |
40 |
92 / 200 |
| 304H |
S30409 |
515 (75) |
205 (30) |
40 |
92 / 200 |
| 316 |
S31600 |
515 (75) |
205 (30) |
40 |
95 / 217 |
| 316L |
S31603 |
485 (70) |
170 (25) |
40 |
95 / 217 |
| 316H |
S31609 |
515 (75) |
205 (30) |
40 |
95 / 217 |
| 321 |
S32100 |
515 (75) |
205 (30) |
40 |
95 / 217 |
| 321H |
S32109 |
515 (75) |
205 (30) |
40 |
95 / 217 |
| 347 |
S34700 |
515 (75) |
205 (30) |
40 |
95 / 217 |
| 347H |
S34709 |
515 (75) |
205 (30) |
40 |
95 / 217 |
| 310S |
S31008 |
515 (75) |
205 (30) |
40 |
95 / 217 |
| 904L |
N08904 |
490 (71) |
215 (31) |
35 |
90 / 200 |
| 410 |
S41000 |
450 (65) |
205 (30) |
20 |
96 / 217 |
| 430 |
S43000 |
450 (65) |
205 (30) |
22 |
89 / 183 |
| 2205 |
S32205 |
620 (90) |
450 (65) |
25 |
31 HRC / 293 |
| 2507 |
S32750 |
800 (116) |
550 (80) |
15 |
32 HRC / 310 |
Hardness columns: HRB / HBW for austenitic and ferritic; HRC / HBW for duplex grades.
5. Heat Treatment Requirements
| Grade Family |
Condition |
Heat Treatment |
Cooling |
| Austenitic (304, 316, 321, 347…) |
Annealed |
Solution anneal at 1010–1120°C (1850–2050°F) min |
Rapid quench — water or air |
| Ferritic (409, 430, 444…) |
Annealed |
Anneal at 760–900°C (1400–1650°F) |
Air cool or water quench |
| Martensitic (410, 420…) |
Annealed |
Anneal at 750–900°C (1380–1650°F) |
Furnace cool to ≤600°C, then air |
| Duplex (2205, 2507…) |
Solution Annealed |
Solution anneal at 1020–1100°C (1870–2010°F) |
Rapid water quench required |
Note: All ASTM A240 material must be supplied in the annealed (or solution-annealed for duplex) condition unless otherwise agreed. Cold-worked or alternative heat-treated conditions require explicit order notation.
6. Testing & Inspection Requirements
| Test |
Requirement |
Reference Standard |
| Chemical Analysis (Heat) |
One per heat / melt |
ASTM A240 Table 1 |
| Chemical Analysis (Product) |
Per heat, Cr / Ni / Mo / C minimum |
ASTM A240 Table 1 (product tolerance) |
| Tensile Test |
One longitudinal specimen per lot |
ASTM A370 |
| Hardness Test |
One per lot; Brinell or Rockwell |
ASTM E18 / E10 |
| Intergranular Corrosion |
For 304 / 316 standard grades when specified |
ASTM A262 Practice A, B, C, or E |
| Detrimental Intermetallic Phase |
Required for duplex 2205, 2507 |
ASTM A923 |
| Grain Size |
ASTM No. 7 or finer — "H" grades |
ASTM E112 |
| Visual & Dimensional |
Per A480/A480M requirements |
ASTM A480/A480M |
7. Dimensions & Tolerances (ASTM A480/A480M)
| Form |
Thickness Range |
Width Range |
Finish |
| Hot-Rolled Plate |
3.0–300 mm |
1000–3000 mm |
No.1 / Pickled & Annealed (1D) |
| Cold-Rolled Sheet |
0.3–5.0 mm |
1000–2000 mm |
2B, 2D, BA, No.4, HL, 8K Mirror |
| Hot-Rolled Coil / Strip |
0.5–20 mm |
Up to 2200 mm |
No.1, 1D |
| Cold-Rolled Strip |
0.002–5.0 mm |
5–900 mm |
2B, BA |
Thickness tolerances per ASTM A480/A480M tables. Plate: ±0.30 mm typical for t ≤ 6 mm. Stricter tolerances available on request.
8. Industries & Applications
| Industry |
Recommended Grades |
Typical Components |
| Chemical & Petrochemical |
304, 316L, 904L, 2205 |
Reactor vessels, storage tanks, heat exchangers, piping |
| Oil & Gas |
316L, 2205, 2507 |
Pressure vessels, separators, scrubbers, offshore equipment |
| Desalination / Marine |
316L, 904L, 2507, 254SMO |
Seawater heat exchangers, evaporators, brine tanks |
| Power Generation |
321H, 347H, 316H, 310S |
Boiler cladding, steam superheaters, nuclear components |
| Food, Pharma & Biotech |
304L, 316L |
Hygienic vessels, clean-in-place systems, fermenters |
| Architecture & Construction |
304, 316 |
Facades, roofing, structural panels, cladding |
9. ASTM A240 vs ASME SA-240 — Key Differences
| Criteria |
ASTM A240 |
ASME SA-240 |
| Issuing Body |
ASTM International |
ASME (BPVC Section II, Part A) |
| Scope |
General industrial & pressure vessel |
ASME Code pressure vessels, boilers, nuclear |
| Technical Requirements |
Full specification |
Identical (adopted from ASTM A240) |
| Material Test Report |
Standard mill certificate |
Certified MTR with full traceability |
| Authorized Inspection |
Not required |
Required per ASME BPVC |
| Code Stamp Equipment |
Not required |
Required for U-Stamp / S-Stamp vessels |
Dual Certification: Most stainless steel plate can be dual-certified as both ASTM A240 and ASME SA-240 without additional cost, provided it meets both specifications. This is standard practice for material used in fabricated pressure equipment.
10. Related Standards
| Standard |
Scope |
Relationship to A240 |
| ASTM A480/A480M |
General Requirements for Flat-Rolled Stainless Steel |
Governs tolerances, finish, test methods |
| ASTM A370 |
Mechanical Testing of Steel Products |
Tensile test method required by A240 |
| ASTM A262 |
Sensitization / Intergranular Corrosion Test |
Common supplementary requirement |
| ASTM A923 |
Detrimental Intermetallic Phase in Duplex SS |
Required for 2205, 2507 when specified |
| ASME SA-240 |
BPVC Section II Part A — pressure vessel plate |
ASME adoption, same material + extra docs |
| EN 10028-7 |
Flat products for pressure vessels — Stainless (EU) |
European equivalent; cross-reference via UNS |
| JIS G4304 / G4305 |
Hot/Cold-rolled SS plate, sheet, strip (Japan) |
Japanese equivalent; common grade mapping |
11. How to Order — Required Information
| No. |
Item |
Requirement / Example |
| 1 |
Specification |
ASTM A240 / ASME SA-240 |
| 2 |
Grade |
e.g., Type 316L (UNS S31603) |
| 3 |
Condition |
Annealed (default); specify if other condition required |
| 4 |
Form |
Plate / Sheet / Strip |
| 5 |
Dimensions |
Thickness × Width × Length (mm or in.) or coil weight |
| 6 |
Surface Finish |
No.1, 2B, 2D, BA, No.4, HL, 8K Mirror, etc. |
| 7 |
Supplementary Tests |
A262 (IGC), NACE MR0175, PMI, UT, impact testing |
| 8 |
Certification |
EN 10204 3.1 Certified Mill Test Report |
| 9 |
Quantity |
Weight (kg / metric ton) or piece count |
12. Frequently Asked Questions
Q: What is ASTM A240?
ASTM A240 (Standard Specification for Chromium and Chromium-Nickel Stainless Steel Plate, Sheet, and Strip for Pressure Vessels and for General Applications) is an ASTM International specification that defines chemical composition, mechanical property minimums, heat treatment, testing, and marking requirements for stainless steel flat-rolled products.
Q: What grades does ASTM A240 include?
ASTM A240 covers over 40 grades: austenitic (304, 304L, 316, 316L, 321, 347, 310S, 904L, 254SMO), ferritic (409, 430, 444), martensitic (410, 420), and duplex/super-duplex (2205/S32205, 2507/S32750). Refer to Table 1 of the standard for the complete listing.
Q: Is ASTM A240 the same as ASME SA-240?
Technically identical in chemistry and mechanical properties. ASME SA-240 is ASTM A240 adopted into ASME BPVC Section II Part A. SA-240 additionally requires Certified Material Test Reports (CMTR) and authorized inspection for ASME code-stamped pressure vessels. Most mills supply dual-certified A240/SA-240 material.
Q: What are the mechanical properties of ASTM A240 316L?
ASTM A240 Type 316L (UNS S31603): minimum tensile strength 485 MPa (70 ksi), yield strength 0.2% offset min. 170 MPa (25 ksi), elongation min. 40% in 2 inches, hardness max. 95 HRB / 217 HBW.
Q: Can ASTM A240 plate be used in pressure vessels?
Yes — ASTM A240 is specifically intended for pressure vessel and general applications. For ASME Code-stamped equipment (U-Stamp), material must also satisfy ASME SA-240 documentation requirements including CMTR and authorized inspector review.
Q: What is the difference between 304 and 316L under ASTM A240?
Type 304 (S30400) is the standard 18Cr-8Ni general-purpose austenitic grade. Type 316L (S31603) adds 2–3% molybdenum for significantly improved pitting and crevice corrosion resistance in chloride and acidic environments, and limits carbon to ≤0.030% for superior weldability. 316L is preferred in marine, pharmaceutical, and chemical processing applications.
Request a Quote — ASTM A240 Stainless Steel Plate / Sheet / Strip
HT PIPE supplies ASTM A240 / SA-240 material across all major grades with EN 10204 3.1 CMTRs. Competitive lead times from affiliated mills in China.
