US standard ASTM A240 and European standard EN 10088-2 cover the same category: corrosion-resistant stainless steel plate and strip. So correspondences like 304 ↔ 1.4301 and 316L ↔ 1.4404 are commonly used in the industry. But "can correspond" does not mean "completely equivalent." Writing only the three characters "304" in a contract is the most dispute-prone approach.
One-Sentence Judgment
Mutual recognition is possible, but you must specify the execution standard + grade + condition. The correct way is "316L, ASTM A240" or "1.4404, EN 10088-2." When only "316L" is written, once chemical composition or mechanical properties fall in the difference zone between the two standards, each party has its own justification.
Common Grade Cross-Reference
- 304 ↔ 1.4301; 304L ↔ 1.4307
- 316 ↔ 1.4401; 316L ↔ 1.4404
- 316Ti ↔ 1.4571 (commonly used in Europe; the corresponding grade in A240 is 316Ti)
- 321 ↔ 1.4541
- 2205 duplex steel ↔ 1.4462
- 310S ↔ 1.4845
Three Details That Actually Differ
① Chemical composition ranges. Largely consistent but boundaries do not fully overlap (individual grades have different upper/lower limits for nickel/chromium and different ways of writing the carbon upper limit). If procurement accepts only according to one standard while the supplier produces according to the other, measured values may "pass A, fail B."
② Mechanical property units and values. US standards use ksi, European standards use MPa; the definition of yield strength (0.2% offset) is consistent but table values are not entirely the same; elongation gauge length may also differ. Unify units and test methods before comparing data.
③ Inspection items and certificates. Both require chemical composition and mechanical properties per lot, but item details (such as whether impact testing is mandatory, how surface quality grading is written) differ. Under the EN system, EN 10204 3.1/3.2 is often cited as the certificate type; under the US system, A240 annexes or customer specifications are often followed.
How to Write Procurement to Avoid Losses
- Specify the material standard (A240 or EN 10088-2), not just the grade;
- Specify the delivery condition (solution annealed/annealed, surface finish 2B/BA/No.1);
- Specify the certificate type (EN 10204 3.1 or 3.2);
- When cross-standard mutual recognition is needed, state clearly in the contract "which standard is used for acceptance" — this sentence can save the entire return process;
- Agree on thickness tolerance separately (A240 and EN 10088-2 have different tolerance tables; see the other article "Thickness Tolerance").
Common Pitfalls
- The drawing says "304," but the delivered plate is produced by a domestic mill according to GB/T 4237 — chemical composition may fully comply, but when the customer re-inspects according to A240, impact or tolerance does not match;
- Mixing up 1.4404 and 1.4401 (316 and 316L): different carbon content leads to different consequences for welded parts;
- Using "304" as a blanket term for both 304 and 304L; when low carbon is actually needed, ordinary 304 is supplied;
- The cross-reference table is directly used as a contract annex, but "which standard is used for acceptance" is not stated.
Tell us your target market and project requirements (US or European standard, whether a 3.2 certificate is needed, which table the thickness tolerance follows), and we will supply according to the corresponding standard and provide per-lot certificates — write the standard clearly, and you will save a round of disputes later.
