Short answer: German and many European drawings identify titanium by Werkstoffnummer rather than ASTM grade. The common mappings are 3.7025 = Grade 1, 3.7035 = Grade 2, 3.7055 = Grade 3, 3.7065 = Grade 4, 3.7165 = Grade 5 (Ti-6Al-4V), 3.7235 = Grade 7, 3.7195 = Grade 9 and 3.7105 = Grade 12. The table below adds UNS numbers and the DIN product standards these drawings usually cite.
Titanium Werkstoffnummer to ASTM grade table
| Werkstoffnummer | ASTM grade | UNS | Material | Typical service |
|---|---|---|---|---|
| 3.7025 | Grade 1 | R50250 | Unalloyed titanium, softest and most formable | Deep drawing, cladding, linings |
| 3.7035 | Grade 2 | R50400 | Unalloyed titanium, the workhorse purity | Chemical process equipment, seawater service |
| 3.7055 | Grade 3 | R50550 | Unalloyed titanium, higher strength | Pressure shells where Grade 2 strength runs short |
| 3.7065 | Grade 4 | R50700 | Unalloyed titanium, highest CP strength | Fittings, airframe details |
| 3.7165 | Grade 5 | R56400 | Ti-6Al-4V | Machined and structural parts |
| 3.7164 | Grade 5 (aerospace variant) | R56400 | Ti-6Al-4V under aerospace-series paperwork | Aerospace parts ordered to aerospace specifications |
| 3.7235 | Grade 7 | R52400 | Titanium with 0.12 to 0.25 percent palladium | Reducing acids, hot chloride, crevice corrosion service |
| 3.7195 | Grade 9 | R56320 | Ti-3Al-2.5V | Tube and hydraulic lines needing more strength than CP grades |
| 3.7105 | Grade 12 | R53400 | Ti-0.3Mo-0.8Ni | Hot brine and chloride process equipment |
These are working correspondences, not word-for-word identical specifications. The chemistry brackets and testing rules in the DIN documents differ in detail from their ASTM counterparts, so the drawing’s own standard always governs. When we quote against a Werkstoffnummer drawing, the reconciliation happens on the mill test certificate, where the reported chemistry and mechanical values can be checked against both documents before material is released.
To look a grade up directly by number, UNS, Werkstoffnummer or standard, use the titanium grade cross-reference tool. The rest of this page covers what a German drawing specifically asks for and how to order ASTM mill product against it.
How do German drawings specify titanium?
A German titanium call-out usually has three parts: the Werkstoffnummer for the material itself, a DIN product standard for the form, and a certificate requirement. Composition sits in DIN 17850 for unalloyed titanium and DIN 17851 for titanium alloys. The product standards are DIN 17860 for plate, sheet and strip, DIN 17862 for bar, and DIN 17864 for forgings. Older drawings may also cite DIN 17861 for seamless tube; that document has been withdrawn, but legacy call-outs to it still circulate and are handled by agreeing the current standard the tube will actually be produced to. The certificate line normally reads EN 10204 3.1, the successor to the old DIN 50049 3.1B, and that is the certificate type Beiyu Titanium issues with ASTM B348 bar, ASTM B265 plate and sheet and ASTM B381 forgings as standard.
What is the difference between 3.7164 and 3.7165?
Both numbers describe Ti-6Al-4V, and the published chemistry tables for the two largely coincide. The practical difference is where each number lives: 3.7164 is the number aerospace paperwork cites, and it brings aerospace-level specification and inspection control with it, while 3.7165 is the industrial variant that lines up with ASTM Grade 5 as supplied to B348 bar or B265 flat product. If a drawing shows 3.7164 together with an aerospace specification, quote it as an aerospace order, not as a commercial Grade 5 substitution. If it shows 3.7165 with a DIN product standard, commercial Grade 5 mill product with a 3.1 certificate is normally what the buyer expects, confirmed against the drawing before quotation.
Which number applies to Grade 23, the ELI version?
Ti-6Al-4V ELI has no separate Werkstoffnummer in common use. German drawings usually write 3.7165 ELI or cite the ASTM standard directly. Note that the UNS number then depends on which standard is ordered: ASTM B348 bar, B265 plate and B863 wire designate Grade 23 as UNS R56407, while the surgical implant specification ASTM F136 uses UNS R56401. The distinction, and when each version is worth paying for, is covered in our Grade 5 vs Grade 23 comparison.
How to order ASTM mill product against a Werkstoffnummer drawing
Most titanium mill production outside Europe runs to ASTM specifications, so buyers holding a DIN drawing usually order the corresponding ASTM grade and verify the DIN requirement on the certificate. For that to work smoothly, an RFQ should state: the Werkstoffnummer and the DIN standard exactly as the drawing shows them, the ASTM grade you intend to accept in their place, form and dimensions with tolerance, the condition and surface finish, and the certificate requirement, normally EN 10204 3.1 with heat traceability. We review the two chemistry brackets side by side at quotation stage and flag any point where the DIN limit is tighter than the ASTM one, so the substitution is agreed before the order is released to production rather than argued about at goods-inward. A full overview of the grades themselves is in the titanium grades comparison guide.