Titanium R56406
UNS R56406 · ASTM F1108 · ISO 5832-3
UNS R56406 is an extra-low-interstitial Ti-6Al-4V investment-casting alloy covered by ASTM F1108 for surgical implant castings, where reduced interstitial content raises fracture toughness while keeping the biocompatibility of the alpha-beta system.
Reference datasheet — R56406 is not in the instant-quote catalog. Upload your part and an engineer will quote it in this grade or suggest the closest stocked equivalent.
Values for the HIP condition
R56406 tempers and conditions
R56406 is supplied in 5 conditions, soft to hard. HIP is the default FabDigit quotes; the values on this page are for it.
Compare all 5 conditionsHide
| Condition · open for datasheet | Best for | Yield MPa | Tensile MPa | Elong. % | Hardness | Conductivity |
|---|---|---|---|---|---|---|
As fabricated | Lowest-cost condition for non-fatigue-critical castings where internal microporosity is acceptable. | 820 | 890 | 9 | 33 HRC | — |
Annealed | Stress-relief/anneal after casting or weld repair when dimensional stability and ductility matter more than fatigue. | 825 | 895 | 11 | 33 HRC | — |
Hot isostatically pressed then annealed/stress relieved | Preferred for large or thin-wall implant castings needing both pore closure and low residual stress before final machining. | 830 | 900 | 12 | 33 HRC | — |
HIPDefault Hot isostatic pressed | Standard supply condition for implants and flight hardware: HIP closes casting porosity and roughly doubles fatigue life. | 840 | 910 | 11 | 34 HRC | — |
Solution treated and aged | Optional for thin-section castings needing maximum strength; sacrifices ductility and toughness and is rarely used for implants. | 930 | 1,020 | 7 | 38 HRC | — |
What is R56406?
UNS R56406 is an extra-low-interstitial Ti-6Al-4V investment-casting alloy covered by ASTM F1108 for surgical implant castings, where reduced interstitial content raises fracture toughness while keeping the biocompatibility of the alpha-beta system. Typical values are 840 MPa yield, 910 MPa tensile, 11 % elongation and 325 HB (34 HRC), with service to 350 °C; conditions on file are F, HIP, ANN, HIP+ANN and STA. Castings require HIP and alpha-case removal to reach rated properties, machinability is poor (20), and processing routes are specialised. Wrought or additively built Grade 23 is the usual alternative when geometry allows. R56406 has a density of 4.43 g/cm³ (0.16 lb/in³), lighter than 89% of titanium grades. It melts at 1,604°C (2,919 °F). R56406 has a yield strength of 840 MPa (122 ksi) and a tensile strength of 910 MPa (132 ksi) — stronger than 63% of titanium grades. Elongation at break is 11% and the elastic modulus is 110 GPa (16 Msi).
What is R56406 used for?
- orthopedic implant housings
- surgical instrument castings
- dental implant components
- biomedical device castings
Advantages
- Tough — resists crack growth — 92 MPa·√m (83.7 ksi·√in), better than 99% of titanium grades
- Polishes to a fine finish — 80/100, better than 98% of titanium grades
Limitations
- Limited formability — 15/100, worse than 93% of titanium grades
- Low electrical conductivity — 1 % IACS, worse than 89% of titanium grades
- Limited ductility — 11%, worse than 87% of titanium grades
- Poor heat conductor — 6.9 W/m·K (3.99 BTU/hr·ft·°F), worse than 83% of titanium grades
R56406 properties
Typical room-temperature values for R56406-HIP; bars are the position among titanium grades.
Physical3
R56406 has a density of 4.43 g/cm³ (0.16 lb/in³), lighter than 89% of titanium grades. It melts at 1,604°C (2,919 °F).
Mechanical16
R56406 has a yield strength of 840 MPa (122 ksi) and a tensile strength of 910 MPa (132 ksi) — stronger than 63% of titanium grades. Elongation at break is 11% and the elastic modulus is 110 GPa (16 Msi).
Thermal6
R56406 is rated for continuous service to 350°C (662 °F). It conducts heat at 6.9 W/m·K (3.99 BTU/hr·ft·°F), worse than 83% of titanium grades. Thermal expansion is 8.7 µm/m·K (4.83 µin/in·°F).
Electrical3
R56406 conducts electricity at 1 % IACS, worse than 89% of titanium grades.
Chemical & Environmental3
Corrosion resistance is excellent (92/100), better than 53% of titanium grades.
Sustainability4
Producing a kilogram of R56406 takes about 700 MJ of energy and emits 45 kg of CO₂ — more than 74% of titanium grades. Typical recycled content is 25%.
Manufacturability8
R56406's machinability is poor (20/100, worse than 68% of titanium grades); weldability very good (70/100); formability poor (15/100).
Common Calculations5
Values are nominal handbook figures for design screening. Certified mill or lot data ships with every FabDigit order on request.
Strength versus weight in the titanium family
Yield strength against density for every titanium grade FabDigit runs. R56406 is highlighted; hover a dot for its name, or open the interactive family chart.
Working with R56406
Is R56406 easy to machine?
Machine at low surface speed (20–40 m/min carbide) with heavy rigid setups, sharp positive-rake tools and flood coolant; avoid dwell to prevent work hardening and titanium fires from fine chips.
Can R56406 be welded?
GTAW/EBW readily in vacuum or full inert shielding with matching ELI filler; weld repair of castings is allowed by ASTM F1108/AMS 4992 with post-weld stress relief and re-inspection.
Can R56406 be formed, bent or molded?
Vacuum investment casting into rammed-graphite or yttria/zirconia face-coat shells; allow 1.0–1.5 % shrink, generous fillets, and plan for HIP plus chemical milling of the alpha case.
R56406 chemical composition (wt %)
Limits by weight percent from the governing specification, written the way the spec states them — a single maximum for impurities, a range for alloying elements, and the base element as balance. Nominal is the typical mid-range value.
| Element | Spec limit (wt %) | Nominal |
|---|---|---|
| Al | 5.5 – 6.75 | 6.1 |
| V | 3.5 – 4.5 | 4 |
| Fe | ≤ 0.2 | 0.12 |
| Olow-interstitial control for toughness | ≤ 0.2 | 0.14 |
| C | ≤ 0.1 | 0.03 |
| N | ≤ 0.05 | 0.02 |
| H | ≤ 0.02 | 0.01 |
| Ymax, when specified | ≤ 0.01 | — |
| Other, eachresidual | ≤ 0.1 | — |
| Other, totalresidual | ≤ 0.4 | — |
| Ti | balance | — |
What surface finishes work on R56406?
Remove alpha case by chem-mill or grinding, then bead-blast, passivate per ASTM F86, and optionally Type II colour or hard anodise; electropolishing gives implant-grade surfaces.
Surface treatments FabDigit runs on titanium parts — pick them in the quote configurator or call them out on the drawing. Each links to its datasheet in the surface-finish library (thickness, specs, call-out, material verdicts).
Thermal Spray
Equivalent designations
Standards and trade names that resolve to Titanium R56406 in FabDigit's catalog. Equivalence is nominal — check the exact specification when certification matters.
- ASTM
- F1108
- ISO
- 5832-3
- Other
- ZTC4
How much does R56406 cost?
R56406 is a high-cost titanium ($$$$), pricier than about 78% of the materials FabDigit quotes. Part price depends far more on geometry, tolerance and quantity than on the raw stock — upload a CAD file for a live quote.
R56406 — frequently asked
What is R56406 used for?
R56406 is typically used for orthopedic implant housings, surgical instrument castings, dental implant components and biomedical device castings. In short: implant-grade cast titanium; highest-strength cast Ti here; ELI chemistry, high toughness.
What is the yield strength of R56406?
R56406 has a typical yield strength of 840 MPa (122 ksi) and a tensile strength of 910 MPa (132 ksi) — stronger than 63% of titanium grades. Strength varies by condition: see the 5 listed tempers.
Is R56406 easy to machine?
Not especially — machinability is rated poor (20/100, worse than 68% of titanium grades). Machine at low surface speed (20–40 m/min carbide) with heavy rigid setups, sharp positive-rake tools and flood coolant; avoid dwell to prevent work hardening and titanium fires from fine chips.
Can R56406 be welded?
Yes — weldability is rated very good (70/100). GTAW/EBW readily in vacuum or full inert shielding with matching ELI filler; weld repair of castings is allowed by ASTM F1108/AMS 4992 with post-weld stress relief and re-inspection.
What surface finishes work on R56406?
Remove alpha case by chem-mill or grinding, then bead-blast, passivate per ASTM F86, and optionally Type II colour or hard anodise; electropolishing gives implant-grade surfaces.
Can R56406 be formed, bent or molded?
Vacuum investment casting into rammed-graphite or yttria/zirconia face-coat shells; allow 1.0–1.5 % shrink, generous fillets, and plan for HIP plus chemical milling of the alpha case.
What is the maximum service temperature of R56406?
R56406 is rated for continuous use to about 350°C (662 °F). Strength falls off well before that limit — check the elevated-temperature data for load-bearing parts.
What is the difference between R56406-HIP and R56406-STA?
HIP is the default condition — standard supply condition for implants and flight hardware: HIP closes casting porosity and roughly doubles fatigue life. STA: optional for thin-section castings needing maximum strength; sacrifices ductility and toughness and is rarely used for implants. Yield strength is 840 MPa in HIP versus 930 MPa in STA.
How much does R56406 cost?
R56406 is a high-cost titanium ($$$$), pricier than about 78% of the materials FabDigit quotes. Part price depends far more on geometry, tolerance and quantity than on the raw stock — upload a CAD file for a live quote.
Sources
- ASTM F1108 — Titanium-6Aluminum-4Vanadium Alloy Castings for Surgical Implants (UNS R56406) — ASTM International (2021)
- AMS 4992 — Titanium Alloy Castings, Investment, 6Al-4V, HIP — SAE International (2019)
- ISO 5832-3 — Implants for surgery, metallic materials, Ti-6Al-4V alloy — ISO (2021)
- ASTM F86 — Surface Preparation and Marking of Metallic Surgical Implants — ASTM International (2021)
- ASM Handbook Vol. 2 — Properties and Selection: Nonferrous Alloys — ASM International (1990)
- ASM Handbook Vol. 19 — Fatigue and Fracture (titanium castings) — ASM International (1996)
- Materials Properties Handbook: Titanium Alloys — ASM International (1994)
- TC4/TC4 ELI (2025)
Property data is compiled from published supplier and standards handbooks and normalised for comparison; hardness values on non-Brinell scales are converted approximately for charting only. Manufacturability limits are FabDigit quote-engine defaults and may be relaxed by engineering review. Nothing on this page is a certification — request mill certs, CoC or material test reports with your order.