Grade 23 (Ti-6Al-4V ELI): Properties, Standards and Selection Guide

Updated August 2026

Grade 23 (Ti 6Al 4V ELI) is an extra-low-interstitial member of the familiar alpha-beta titanium alloy family and is more conventionally written Ti-6Al-4V ELI. The grade label is only the starting point for a usable material identity. A defensible order or design record also names the governing specification and revision, product form, material condition, process route, applicable UNS designation, and heat or lot evidence.

The practical task is to read that identity, match a standard to the actual form and route, interpret property claims, compare Grade 23 with Grade 5, and inspect a certificate without confusing material compliance with finished-component approval. For available forms and commercial supply questions, use the separate Grade 23 Ti-6Al-4V ELI material options page.

In the alloy shorthand, Al and V mean aluminum and vanadium. The accepted chemistry still comes from the governing specification and the traceable heat result; expanding the short name isn’t a substitute for those records.

The 6-Part Material Identity Stack

A reliable way to read Grade 23 is through a six-part identity stack: grade, specification revision, product form, material condition, designation, and traceable evidence. Miss one layer and the same alloy nickname can lead to a different acceptance route, a different test set, or a property table that doesn’t apply to the material in hand.

1. Alloy or grade name: Grade 23, Ti-6Al-4V ELI, or the exact ordered designation.
2. Governing specification and revision: the document that defines scope and acceptance requirements.
3. Product form: sheet, plate, bar, billet, forging, wire, powder-bed-fused component, or another stated form.
4. Material condition: annealed or another explicitly ordered and documented condition.
5. UNS or specification identity: the designation shown by that standard, not one copied from a generic web table.
6. Heat, lot, and test evidence: the records that connect results to the marked material.

One useful warning appears in the UNS designations. ASTM’s current public F136-26 page identifies wrought annealed surgical-implant material as UNS R56401. Public pages for ASTM B265-25, B348, and B381-26 identify Grade 23 or F-23 as UNS R56407 in their general wrought product-form scopes. That does not establish broad interchangeability. Buyers should preserve the exact standard, revision, form, and designation instead of flattening them into one internet label.

Match the Standard to the Product Form, Process and Application

Choose the Grade 23 standard from the required form, manufacturing route, and application context, not from the alloy name alone. The public scopes below are a navigation map; they don’t replace the purchased standard, drawing, or contract. Every route keeps its own edition, size, condition, testing, and supplementary-requirement boundaries.

Source basis: public ASTM and SAE title, status, abstract, and scope pages. Exact acceptance values and requirements must be taken from the applicable purchased edition and contract.

Wrought surgical-implant material

ASTM F136-26 publicly covers chemical, mechanical, and metallurgical requirements for wrought annealed Ti-6Al-4V ELI, UNS R56401, used in the manufacture of surgical implants. Named forms include strip, sheet, plate, bar, forging bar, and wire. It does not say that a finished implant is approved, safe for a patient, or suitable for a particular design. Those conclusions need device-level manufacturing, validation, biological, regulatory, and clinical evidence outside the material specification.

General wrought product forms

ASTM B265-25 covers annealed strip, sheet, and plate; B348 covers annealed bars and billets; and B381-26 covers annealed forgings. Research opened a historical B348 edition, so the active revision must be confirmed at purchase-order time. Requirements cannot be moved from sheet to bar or from bar to forging simply because each page contains the words Grade 23.

Aerospace material route

SAE AMS4930M is a material specification for annealed 6Al-4V ELI in stated bars, wire, forgings, rings, and stock. Its November 2025 public scope includes flash-welded rings through 4.000 inches (101.60 mm), bars through 10.000 inches (254 mm), and a stated maximum cross-sectional area of 79 square inches (509.7 cm²) for part of that bar range. Those public limits illustrate why the exact revision, form, and size matter; they do not replace the drawing or authorize every aerospace use.

Additive manufacturing route

ASTM F3001-14(2021) treats full-melt powder-bed-fused Ti-6Al-4V ELI components as a separate evidence route. Its public scope covers feedstock, process planning, chemical composition, microstructure, mechanical properties, thermal processing, hot isostatic pressing where applicable, inspection, certification, marking, and quality-program requirements. Powder-built components cannot inherit wrought bar or forging property claims just because the nominal alloy family matches.

Revision control is a live acceptance question

FDA’s reviewed record lists ASTM F136-13 and says the complete standard is recognized. ASTM’s current page lists F136-26 as active. No automatic substitution follows from those two public records. Instead, check the current FDA recognition database, the applicable submission strategy, the drawing, and the purchase contract before claiming regulatory or contractual acceptance.

What Lower Interstitial Limits Change—and What ELI Does Not Prove

ELI means extra low interstitial: selected interstitial elements such as oxygen, nitrogen, hydrogen, and carbon are controlled more tightly under the applicable specification. Peer-reviewed literature associates reduced interstitial content in Ti-6Al-4V ELI with ductility and fracture-toughness benefits. This defensible relationship remains qualitative and condition-dependent, not a universal percentage improvement.

Interstitial control changes part of the chemical composition and the behavior it can support, but the ELI grade name does not freeze the material’s entire history. Melting practice, form conversion, heat treatment, microstructure, surface state, test orientation, and manufacturing route still influence the property evidence available to a designer.

Terms such as “medical grade” or “aerospace grade” are especially risky when they stand alone. They describe a context, not a complete proof chain. Buyers should ask what specification, edition, product form, condition, and heat or lot records support the label.

How to Read a Grade 23 Property Table Without Misusing It

Use a Grade 23 property value only after seven labels are attached: standard edition, form, condition and route, test orientation or location, test method and temperature, requirement versus typical value, and traceable source. Without those labels, a precise-looking number may be irrelevant to the supplied material or unsafe to use as a design allowable.

Fatigue and fracture claims need extra care

One peer-reviewed study of beta-solution-treated Ti-6Al-4V ELI found that cryogenic treatment and the resulting microstructure changed high-cycle-fatigue and fatigue-crack-propagation behavior in that experimental system. No generic fatigue number follows. Thermal history and microstructure can alter results, so experimental data must be matched to the production condition and design method before use.

Physical properties are not the same as acceptance properties

Physical properties such as density or elastic modulus can help with early engineering estimates, but a general reference value isn’t a substitute for the chemical and mechanical acceptance requirements of the ordered specification. The same caution applies to high strength-to-weight ratio, corrosion resistance, machinability, and cryogenic behavior: each claim needs a defined condition, method, and application boundary before it becomes actionable.

Grade 23 vs Grade 5: Use a 4-Question Evidence Test

Grade 23 and Grade 5 belong to the commonly named Ti-6Al-4V alloy family, but ELI shouldn’t be reduced to “better titanium.” Grade 23 applies tighter interstitial controls under its governing specification. Selection follows the drawing, failure mode, product route, service conditions, and evidence obligation, not a universal ranking.

The separate Ti-6Al-4V Grade 5 reference explains the conventional alloy family. Before replacing one grade with the other, work through this four-question test:

1. Is ELI explicitly required? Check the drawing, customer specification, standard, and regulatory strategy.
2. What failure mode is being controlled? Identify the ductility, fracture, fatigue, environment, or process concern rather than choosing by reputation.
3. What form, route, and condition will be supplied? Bar, sheet, forging, and additive material do not share an automatic evidence package.
4. What closes the decision? Define the certificate, qualification, inspection, and design evidence required by the responsible authority.

Application Claims Need an Evidence Ladder

Medical, dental, aerospace, cryogenic, and additive-manufacturing applications are contexts, not self-executing approvals. A material certificate can confirm defined alloy requirements, but it can’t close design validation, process qualification, inspection, regulatory acceptance, or fitness for service on its own. Each field needs an evidence ladder beyond the grade name.

Medical and dental components

For medical components, the ladder starts with the applicable material specification, then adds component manufacturing controls, surface and cleaning state, design verification and validation, biological evaluation where required, and the relevant device regulatory pathway. ASTM F136 is a material specification for use in manufacture. It is not an approval badge for a finished implant, and this article is technical material information rather than medical advice.

Aerospace and cryogenic components

For aerospace components, the ladder connects material specification to the engineering drawing, approved process plan, inspection or NDT requirements, design allowables, and component acceptance. AMS4930M should be used only within its form, condition, revision, and size scope. A Grade 23 certificate alone does not qualify every safety-critical part or establish behavior across all cryogenic temperatures.

Additively manufactured components

An AM ladder begins with feedstock and powder controls, then adds qualified machine and build parameters, build orientation, thermal processing and hot isostatic pressing when specified, microstructure and mechanical testing, surface finishing, inspection, and final component qualification. ASTM F3001 gives this route its own structure. Wrought, forged, and powder-bed-fused property claims must remain separate unless a qualified engineering basis connects them.

Read the Test Certificate as an Evidence Chain

Read a Grade 23 test certificate as a chain, not a page of isolated numbers. Its first link is the drawing or purchase requirement; the last is a set of markings connected to the delivered material. A certificate is useful only when every link identifies the same standard, grade, form, condition, heat or lot, and required result set.

ASTM F136’s public scope supports mentioning heat analysis, product-analysis tolerances, and required tension and bend testing at material-specification level. That does not mean every Grade 23 order uses the same tests. Required tests remain specification- and contract-specific.

Manufacturing Implications Belong to the Process Plan

Grade 23 affects manufacturing decisions, but the grade name alone does not supply universal process parameters. Machining, welding, heat treatment, and additive manufacturing must be controlled by qualified process data tied to geometry, equipment, condition, acceptance criteria, and service risk.

For machining, heat generation, tool wear, distortion, and surface integrity belong in the method qualification; a generic speed or feed would be misleading here. For a weld, shielding, cleanliness, joint preparation, procedure qualification, and post-process acceptance must follow the relevant design and quality system. Heat treatment can change material condition and microstructure, which changes the relevance of published property data. Additive manufacturing must preserve the separate F3001 evidence route instead of borrowing from wrought references.

If you’re still working out how form, grade, and standard fit together, use the broader titanium products hub guide. TiAlloy’s titanium material overview is a separate navigation point for product families. Neither link replaces project-specific engineering review, process qualification, or post-process acceptance.

Seven Evidence Questions Before Design Release or Procurement

Before release or procurement, ask these seven practical evidence questions in sequence. This is an engineering-control check, not a commercial RFQ template. A “yes” helps only when the answer names the document, revision, responsible owner, and traceable record behind it.

• 1. Which standard and revision govern?
• 2. Which product form and material condition are required?
• 3. Which Grade 23 and UNS identity applies within that specification?
• 4. Are published properties requirements or typical values for the relevant condition?
• 5. Which manufacturing route and supplementary qualifications apply?
• 6. Which tests and traceability documents must be delivered?
• 7. Who owns finished-component approval and fitness-for-service decisions?

If any answer stops at “Grade 23,” the evidence chain is incomplete. Do not fill that gap from a supplier datasheet; return to the drawing, contract, applicable standard, and responsible engineering or regulatory authority.

Frequently Asked Questions

Use the Grade Name as the Start of the Decision

Grade 23 titanium becomes actionable only when its full identity and evidence chain are intact. Start with the standard and revision, then lock the form, condition, route, designation, heat or lot, required tests, and responsible approval owner. That keeps a useful alloy name from turning into an unsupported property claim or an implied component approval.

For company context, see TiAlloy’s material and documentation workflow. If your project already has a drawing, standard family, and evidence question, Discuss the applicable Grade 23 specification and evidence.