Material number 1.4404: 316L
1.4404 is the European material number (Werkstoffnummer, EN 10027-2) for 316L, low-carbon austenitic chromium-nickel-molybdenum stainless steel specified in ASTM A240.
Reading 1.4404 digit by digit
An EN 10027-2 number has the form 1.XXYY. The leading 1 marks it as steel. The pair 44 is the steel group, and for this number that group is stainless steels with ≥ 2.5 % Ni, with Mo. The final pair 04 is a sequential count inside that group and carries no meaning of its own — 1.4404 is simply the 4th entry registered there.
The group digits are the useful part. Reading 44 tells you what kind of steel you are looking at before you know anything else about it, and the 2 other numbers from group 44 held here are listed below.
1.4404 identity card
| Item | Value |
|---|---|
| Material number (EN 10027-2) | 1.4404 |
| Symbolic grade name | 316L |
| Steel group | 44 — stainless steels with ≥ 2.5 % Ni, with Mo |
| Sequential number in group | 04 |
| Specified in | ASTM A240 |
| Steel family | Stainless steel |
| Also carries UNS | S31603 |
| Yield, first condition in the table | ≥ 170 MPa (sheet/plate, annealed (ASTM A240)) |
| Tensile, same condition | ≥ 485 MPa |
| Cross-references held | 4 grades in 2 systems |
316L (1.4404, UNS S31603) is 316 with carbon capped at 0.030 %: the same molybdenum-bearing alloy, specified so welds do not sensitise.
Full data sheet for 316L → · Equivalent grades → · ASTM A240 →
Group 44 — the neighbouring numbers
Same group digits, so the same broad class of steel. The sequential digits do not rank them.