Grade 23 Titanium (Ti-6Al-4V ELI)
UNS R56401 — Ti-6Al-4V with tighter oxygen/iron/nitrogen control ("extra low interstitial"). The interstitial reduction is what buys fracture toughness and reliable performance at thin sections and low temperature; that property story is exactly why the medical and cryo specs are written against ELI.
| Property | Grade 23 (ELI) | Grade 5 |
|---|---|---|
| Tensile | 860 MPa | 895 MPa |
| Oxygen max | 0.13 % | 0.20 % |
| Iron max | 0.25 % | 0.40 % |
| Driving property | toughness / fatigue | maximum strength |
Interstitial Control Explained
Oxygen and iron are the hardeners that embrittle titanium. Gr23 caps them tighter than Gr5, sacrificing ~35 MPa of nominal tensile (published 860 vs 895 MPa) for toughness and consistent fatigue behaviour.
Medical Device Context — Standards Only
ASTM F136 and ISO 5832-3 are the ELI mill specs device makers buy to; F67 is the CP-Ti companion. We quote material and machining against published standards; device qualification (ISO 13485 manufacturing, biocompatibility testing) sits with the device programme, and we make no such claims. Send the standard version and acceptance requirement with the enquiry.
Forms
Bar (incl. fine drawn), plate, wire. Gr23 vs Gr5 selection: see Grade 5.