ASTM B265, B348 & B338 — Titanium Standards Quick Reference for Sheet, Bar and Tube Buyers
A buyer’s quick-reference to the three core ASTM standards that govern wrought titanium: B265 (strip / sheet and / plate), B348 (bar and billet) and B338 (seamless and welded tube). Scope, applicable grades, dimensional conventions, and the room-temperature mechanical property bands every specifier should know before signing a mill cert.
1. Why ASTM Titanium Standards Matter for Buyers
Titanium is sold under half-a-dozen nomenclature layers: the chemistry designation (GR1–GR29, alloy 6-4, CP-Ti), the product-form standard (B265 / B348 / B338 / F67 / F136), the ASTM material group, the ASME SB-prefix when the part ships into a pressure vessel, and the mill’s proprietary brand. A specifier that signs a mill cert without checking all three layers risks accepting a chemistry that looks right on paper but does not match the form on the shop floor.
The three standards in this reference — ASTM B265 (sheet/plate), ASTM B348 (bar/billet), and ASTM B338 (tube) — cover roughly 90 % of the wrought titanium that crosses an industrial buyer’s desk. Each standard defines the chemistry, dimensional tolerances, mechanical property bands, inspection regime, and certification requirements for one wrought form. The chemistry tables are intentionally aligned across the three standards, so a GR2 listed on B265 and a GR2 listed on B348 should fail the same compositional limits; the divergence is in form-specific tolerance, surface finish, and test methods.
For a buyer who has to balance cost, lead-time, and mechanical property bands, the practical question is not “Which standard?” but “Which form of titanium, in which grade, with which condition?” The next four sections break down each standard’s scope, then two reference tables lay out the chemistry and room-temperature mechanical properties for the eight grades that show up most often in industrial RFQs — GR1, GR2, GR3, GR4, GR5, GR7, GR9 and GR12. For a deeper walk-through of the grade family itself (CP grades vs. alpha vs. alpha-beta vs. near-alpha), the equivalent designations, and the difference between “GR5” and “GR23 ELI”, see our Titanium Grades Explained: GR1 to GR5 Comparison.
2. ASTM B265 — Strip, Sheet and Plate
B265 covers flat-rolled wrought titanium in three sub-forms: strip (thinner than 0.25 in / 6.35 mm, supplied in coil or cut length), sheet (0.25 in to 0.187 in / 4.76 mm, supplied as flat cut-length pieces), and plate (thicker than 3/16 in / 4.76 mm, supplied as flat cut-length pieces). Below 0.05 mm thickness the product usually steps out of B265 and into ASTM F67 (unalloyed titanium for surgical implant applications) or a proprietary cold-rolled spec.
Grade coverage in B265 spans the commercially-pure grades (GR1–GR4), the workhorse alpha-beta alloy Ti-6Al-4V (GR5), the palladium-stabilized GR5 variant for reducing-acid service (GR24 / GR29), the near-alpha Ti-3Al-2.5V (GR9), the titanium Grade 12 (GR12, Ti-0.3Mo-0.8Ni) for chemical service, and the extra-low-interstitial GR23 for medical and cryogenic use. Tensile and yield property bands are tabulated per grade in the standard, with separate tables for annealed and solution-treated conditions.
Dimensional conventions in B265 are based on thickness × width × length, with tolerance classes for thickness, width, length, flatness, and edge condition. The standard permits dual certification — a single piece can be marked B265 + F67 if it meets both specs — which is how medical-grade sheet / plate often arrives with an ASTM B265 / F67 dual mark. For sheet-vs-plate thickness ranges, surface finish options (mill finish, 2B, polished, anodised), and the practical differences in cut-to-size order conventions, see our Titanium Sheet vs Plate selection guide.
3. ASTM B348 — Bars and Billets
B348 is the standard for wrought titanium bar and billet in round, square, and hexagonal cross-sections, plus rectangular bar up to a defined width. The standard covers both hot-worked and cold-finished product, with separate dimensional tolerance bands for each. A billet under B348 is a semi-finished hot-worked round or square bar intended for further forging or machining; a bar is finished product in the as-rolled, as-drawn, annealed, or solution-treated condition ready for machining into parts.
B348 sets out the chemistry bands (which align with B265 / B338 for the same grade designation), the heat-treatment condition options (annealed, solution-treated, solution-treated-and-aged — “M” / “STA”), the dimensional tolerance bands (diameter, length, straightness, out-of-round), and the inspection regime (chemistry, mechanical properties, ultrasonic on demand). The mechanical property bands in B348 are wider than those in B265 because bar / billet products are typically used as forging / machining feedstock, not as finished flat product; a specifier tightening the band should call this out on the mill order and require a sample-tested mechanical report per heat.
For round bar, the practical size envelope runs from about 6 mm (cold-drawn finish) to 300 mm (hot-rolled, rough-turned). Hexagonal and square cross-sections are common for medical machining feedstock under F136. For round bar tolerances, surface finish options (centreless-ground, peeled, polished), and grade-availability bands across CP GR1–GR5, see our Titanium Bar & Rod: Specs, Grades and Applications reference.
4. ASTM B338 — Seamless and Welded Tubes
B338 is the dedicated standard for seamless and welded titanium tube intended primarily for condensers, heat exchangers, and hydraulic / instrumentation service. The standard covers both seamless (extruded or cold-pilgered) and welded (cold-formed and inert-gas-welded) tube, with grade coverage from GR1 through GR12 plus the heat-exchanger-favoured Ti-0.3Mo-0.8Ni GR12 and Pd-stabilised GR7 for dilute reducing-acid service. OD range typically spans 6 mm to 100 mm, with wall thickness in the BWG schedule plus custom-extruded wall bands up to about 6 mm.
Inspection regime under B338 is more demanding than for sheet / plate because tubes carry pressure: each length is subject to either hydrostatic test (the default), eddy-current test (for non-ferritic grade selection), or pneumatic test on agreement. The standard also requires a flare test, a flange test, and a reverse-bend test on the weld zone of welded tube, which is why welded B338 tube is generally sold into lower-pressure service than seamless. The mechanical property bands (tensile, yield, elongation) align with B265 / B348 for the same grade designation.
For seamless vs. welded tube selection, OD / wall schedule options, U-bend tube availability, and the ASME SB-338 cross-reference for pressure-vessel code work, see our Titanium Tube & Pipe Selection Guide.
5. Grade Comparison — Chemical Composition
The table below summarises the chemical composition limits for the eight most commonly specified wrought titanium grades across B265 / B348 / B338. Values are mass-percent, maximum unless noted as a range. CP grades (GR1–GR4) are unalloyed, with strength controlled by the interstitial oxygen content; alpha / alpha-beta grades (GR5, GR9, GR12) are alloyed for higher tensile bands and specific corrosion resistance. For full composition limits including minor elements, trace metals, and per-product-form notes, refer to the current revision of each standard.
| Grade | Designation | N (max) | C (max) | H (max) | Fe (max) | O (max) | Alloying (typical) |
|---|---|---|---|---|---|---|---|
| GR1 | CP-Ti | 0.03 | 0.08 | 0.015 | 0.20 | 0.18 | — |
| GR2 | CP-Ti (“workhorse”) | 0.03 | 0.08 | 0.015 | 0.30 | 0.25 | — |
| GR3 | CP-Ti | 0.05 | 0.08 | 0.015 | 0.30 | 0.35 | — |
| GR4 | CP-Ti (highest strength CP) | 0.05 | 0.08 | 0.015 | 0.50 | 0.40 | — |
| GR5 | Ti-6Al-4V (alpha-beta) | 0.05 | 0.08 | 0.015 | 0.30 | 0.20 | 5.5–6.75 % Al, 3.5–4.5 % V |
| GR7 | Ti-Pd (CP + Pd) | 0.03 | 0.08 | 0.015 | 0.30 | 0.25 | 0.12–0.25 % Pd |
| GR9 | Ti-3Al-2.5V (near-alpha) | 0.03 | 0.08 | 0.015 | 0.25 | 0.15 | 2.5–3.5 % Al, 2.0–3.0 % V |
| GR12 | Ti-0.3Mo-0.8Ni (near-alpha) | 0.03 | 0.08 | 0.015 | 0.30 | 0.25 | 0.2–0.4 % Mo, 0.6–0.9 % Ni |
6. Mechanical Properties at Room Temperature
The table below summarises the room-temperature mechanical property bands for the same eight grades in the annealed condition, as called out in B265 / B348 / B338. Tensile and yield are minimum values; elongation is a minimum. For product-specific conditions (cold-worked, solution-treated, STA), refer to the per-grade tables in the current standard revision; for elevated-temperature property bands, refer to ASME SB-265 / SB-348 / SB-338.
| Grade | Condition | Ultimate Tensile (min, MPa) | Yield 0.2 % (min, MPa) | Elongation (min, %) |
|---|---|---|---|---|
| GR1 | Annealed | 240 | 170 | 24 |
| GR2 | Annealed | 345 | 275 | 20 |
| GR3 | Annealed | 450 | 380 | 18 |
| GR4 | Annealed | 550 | 483 | 15 |
| GR5 | Annealed | 895 | 828 | 10 |
| GR7 | Annealed | 345 | 275 | 20 |
| GR9 | Annealed | 620 | 483 | 15 |
| GR12 | Annealed | 483 | 345 | 18 |
7. Frequently Asked Questions
Which ASTM standard should I cite on a mill cert?
It depends on the product form you are buying. Strip, sheet, plate arrives against ASTM B265. Round, square, or rectangular bar (including billet) arrives against ASTM B348. Seamless or welded tube arrives against ASTM B338. If the part ships into an ASME Boiler & Pressure Vessel Code context, the matching “SB-” prefix is used (SB-265, SB-348, SB-338). For surgical or implant applications, the matching standard is F67 (unalloyed) or F136 (Ti-6Al-4V ELI / GR23), often dual-certified with the B-prefix.
Is ASTM B265 GR2 the same as ASME SB-265 GR2?
Chemically, mechanically, and dimensionally, yes. The “SB-” prefix is the ASME Boiler & Pressure Vessel Code reference to the same ASTM specification, adopted into the ASME code with the same composition and mechanical property bands. A piece dual-marked B265 / SB-265 is identical material; the dual mark lets the same piece of stock be accepted in both an ASTM and an ASME code context without re-certification.
Can I get B265 plate in GR5 below 4 mm?
Technically, anything thinner than about 3/16 in (4.76 mm) re-classifies as sheet under B265, not plate. In practice, mills routinely supply GR5 Ti-6Al-4V down to 0.5 mm thickness under the B265 sheet envelope, often dual-certified to AMS 4911 or MIL-T-9046 for aerospace. Below 0.5 mm you are typically in foil territory, which often leaves B265 entirely and falls under F67 (CP) or a proprietary cold-rolled spec for alloys.
Does ASTM B348 cover flat bar?
Yes, with caveats. B348 covers round, square, and hexagonal cross-sections explicitly; rectangular bar up to a defined width is also covered. Strip — narrow, flat-rolled, thin product typically supplied in coil — is covered by B265, not B348. For bar wider than the B348 maximum, the mill will often supply to a proprietary spec or to AMS 4928 / AMS 4911 for aerospace-grade rectangular bar.
Why are there both annealed (M) and solution-treated-and-aged (STA) conditions in B348?
B348 covers wrought titanium in several heat-treatment conditions because the same grade can be specified in different microstructural states for different duty. Annealed (“M”) gives the best ductility and formability, with the lowest tensile strength. Solution-treated-and-aged (“STA”) is applied to alpha-beta alloys such as GR5 (Ti-6Al-4V) and gives much higher tensile and yield bands at the expense of some ductility. For general machining feedstock the annealed condition is the default; for fatigue-loaded structural parts the STA condition is the default.
What documentation should I require with each ASTM titanium delivery?
At minimum, a mill test report (MTR) per ASTM A555 or EN 10204 / 3.1 with chemistry per heat and mechanical properties per lot. For aerospace, medical, or pressure-vessel code work, request dual certification where applicable (B265 / F67, B348 / F136, B265 / SB-265), traceability per lot, and a statement of compliance with the current revision year of the standard. For tube (B338), request the inspection certificate covering the hydrostatic or eddy-current test result for each length.
References
- ASTM B265 — Standard Specification for Titanium and Titanium Alloy Strip, Sheet, and Plate (current revision).
- ASTM B348 — Standard Specification for Titanium and Titanium Alloy Bars and Billets (current revision).
- ASTM B338 — Standard Specification for Seamless and Welded Titanium and Titanium Alloy Tubes for Condensers and Heat Exchangers (current revision).
- ASTM F67 — Standard Specification for Unalloyed Titanium for Surgical Implant Applications.
- ASTM F136 — Standard Specification for Wrought Titanium-6Aluminum-4Vanadium ELI Alloy for Surgical Implant Applications (GR23).
- ASME SB-265 / SB-348 / SB-338 — Boiler and Pressure Vessel Code references to the ASTM B-prefixed standards above.
- ISO 5832-2 — Implants for surgery — Metallic materials — Part 2: Unalloyed titanium.
- ISO 5832-3 — Implants for surgery — Metallic materials — Part 3: Wrought titanium 6Al-4V alloy.
- TOPTITECHS Knowledge: Titanium Grades Explained: GR1 to GR5 Comparison.
- TOPTITECHS Knowledge: Titanium Sheet vs Plate: What’s the Difference and How to Choose.
- TOPTITECHS Knowledge: Titanium Bar & Rod: Specs, Grades and Applications.
- TOPTITECHS Knowledge: Titanium Tube & Pipe: Selection Guide by Standard, Size and Application.
Buying titanium to ASTM B265, B348 or B338? Send your grade, form, dimensional envelope, and the relevant standard revision to our applications team for a same-day quotation with mill-test-report traceability. Browse our Titanium Materials range for sheet, plate, bar, billet, tube and foil in GR1–GR5, GR7, GR9 and GR12, all supplied with EN 10204 / 3.1 mill certification.