Workshop
Steel and aluminium grade designation
In short
Type or pick a designation: the calculation splits it and gives the meaning of each part from the published rules (EN 10027-1 and -2, EN 573-1 and EN 515, UNS, ASTM, AISI), the material family and the known equivalents. Example: S355J2+N = structural steel, minimum yield strength 355 MPa, 27 J at −20 °C, normalised.
Calculation
Example calculated with the tool’s default values.
Inputs
- Designation
- S355J2+N
Results
- Structural steel
- S355J2+NEN 10027-1, table 1
- Structural steel
- S
- Minimum yield strength 355 MPa (smallest thickness range)
- 355
- Impact energy 27 J at −20 °C (Charpy test)
- J2
- Product condition or coating: normalised (or normalised formed)
- +N
Worked example
Every value in this section belongs to the example, calculated with the tool’s default values.
- Equivalent = close grade, not identical: compare chemistry, properties and impact; the material certificate (EN 10204 3.1) is what counts.
Step-by-step calculation
European steel name, by application and mechanical properties
EN 10027-1, table 1
S · 355 · J2 · +N
Known equivalents
| System | Designation |
|---|---|
| EN 10027-2 | 1.0577 |
| ASTM | A572 Gr. 50 |
How to use it
- Type the designation as written on the certificate or drawing, or pick an example.
- Read the material family and the standard that defines the designation.
- Read the meaning of each part: letter, yield strength, impact energy, condition, contents.
- Compare with the known equivalents, then check the material certificate.
Frequently asked questions
What does S355J2+N mean?
S = structural steel; 355 = minimum yield strength of 355 MPa in the smallest thickness range; J2 = impact energy of 27 J at −20 °C (Charpy test); +N = delivered normalised (or normalising formed). Rules of EN 10027-1, table 1. Known equivalents: 1.0577 (EN 10027-2), ASTM A572 Gr. 50.
What does P265GH mean?
P = pressure vessel steel; the number that follows is the minimum yield strength in MPa, in the smallest thickness range; G = other characteristics; H = high temperature. Rules of EN 10027-1, table 2. Known equivalents: 1.0425 (EN 10027-2), ASTM A516 Gr. 60.
How do I read a material number like 1.4404?
1 = material group steel; 44 = steel group stainless, Ni ≥ 2.5 %, with Mo, without Nb or Ti; 04 = sequence number in the group, which carries no property (EN 10027-2). 1.4404 matches X2CrNiMo17-12-2, AISI type 316L and UNS S31603.
How is X2CrNiMo17-12-2 read?
X = high alloy steel (at least one element ≥ 5 %); the first number is the average carbon in hundredths of a percent; then the elements and their average contents: chromium ≈ 17 %, nickel ≈ 12 %, molybdenum ≈ 2 %. Chromium ≥ 10.5 %: stainless steel; carbon ≤ 0.03 %: low carbon “L” grade, preferred for welding.
What do A106 Gr. B and A312 TP316L mean?
An ASTM designation first names a product: A106 = seamless carbon steel pipe for high temperature service; A312 = seamless, welded and heavily cold worked austenitic stainless pipe. The grade comes next: Gr. B, or TP316L (AISI type 316L). Known equivalents: P235GH (1.0345) for A106 Gr. B, 1.4404 for TP316L.
How is EN AW-6060 T6 read?
EN AW = wrought aluminium (EN 573-1); 6060 = 6xxx series, magnesium and silicon alloy; T6 = solution heat treated then artificially aged (EN 515). Known equivalents: AlMgSi (EN 573-2), AA 6060, UNS A96060.
Limits
Indicative results: decoding follows the designation rules, it does not check that the grade exists in a product standard. An equivalent is a close grade, not an identical one: compare chemistry, properties and impact; the material certificate (EN 10204 3.1) is what counts.
Sources
- EN 10027-1:2005 : Tableaux 1 à 4, 8, 12 à 18 (texte publié par Sanyo Steel) ; recoupé SpawBaza et Wikipédia « Steel grades » (link)
- EN 10027-2:2015 : Numéros matière 1.XXYY, groupes d’aciers (Sanyo Steel = Matplus = Calibr) (link)
- UNS (ASTM E527 / SAE J1086) : Séries A à Z (Wikipédia = Steelstandart) (link)
- ASTM, titres des spécifications : store.astm.org, relus le 10/11/2026 (link)
- EN 573-1 et EN 515 (aluminium) : European Aluminium § 3.2.3 et 3.2.4 = Alumeco = Wikipédia « Aluminium alloy » (link)
- Équivalences : Fiche Nuances de Metalary ; SpawBaza ; Calibr = Motun Metal (inox) (link)