Titanium Ti-5553
UNS R58553
Ti-5553 (Ti-5Al-5V-5Mo-3Cr) is a metastable beta titanium alloy developed for large landing-gear forgings, offering a better fracture-toughness-to-strength balance than Ti-10-2-3.
Values for the O condition
Ti-5553 tempers and conditions
Ti-5553 is supplied in 7 conditions, soft to hard. O is the default FabDigit quotes; the values on this page are for it.
Compare all 7 conditionsHide
| Condition · open for datasheet | Best for | Yield MPa | Tensile MPa | Elong. % | Hardness | Conductivity |
|---|---|---|---|---|---|---|
Solution annealed | Pick for maximum ductility and easiest machining/forming before the customer performs the final aging cycle. | 830 | 890 | 20 | 30 HRC | — |
ODefault Annealed | Standard as-supplied mill condition for bar, billet and forging stock; balanced strength and ductility before final aging. | 900 | 960 | 16 | 33 HRC | — |
As fabricated | Rough billet, bar or forging supplied without final heat treatment; properties uncontrolled, intended for subsequent ST/aging. | 930 | 1,000 | 12 | 35 HRC | 1.1 % IACS |
Beta annealed, slow cooled and aged | Pick for very thick landing-gear forgings where fracture toughness and section-size uniformity dominate over ultimate strength. | 1,020 | 1,100 | 10 | 36 HRC | — |
Solution treated and overaged | Use when fracture toughness and thermal/dimensional stability are prioritised over peak strength. | 1,040 | 1,120 | 12 | 37 HRC | — |
Solution treated and aged | The standard high-strength delivery condition for landing-gear and structural forgings; use when 170 ksi class strength through thick sections is required. | 1,150 | 1,230 | 9 | 40 HRC | — |
Solution treated and aged to high-strength schedule | Choose when peak strength matters more than toughness (small, low-K-critical parts, fasteners, actuator components). | 1,240 | 1,320 | 6 | 43 HRC | — |
What is Ti-5553?
Ti-5553 (Ti-5Al-5V-5Mo-3Cr) is a metastable beta titanium alloy developed for large landing-gear forgings, offering a better fracture-toughness-to-strength balance than Ti-10-2-3. Supplied mainly as forgings and machined bar stock, it provides 900 MPa yield, 960 MPa tensile, 16% elongation and 33 HRC in the default condition, with ST, STA, STA-HS, STOA and BASCA heat treatments on file for tailored strength and toughness. Service is limited to about 300 °C, machinability is the worst of the titanium grades listed (score 16), and welded joints lose aged strength unless re-solution treated and aged. Ti-10-2-3 is the established alternative where forging experience and cost dominate. Ti-5553 has a density of 4.65 g/cm³ (0.168 lb/in³), heavier than 90% of titanium grades. It melts at 1,580°C (2,876 °F). Ti-5553 has a yield strength of 900 MPa (131 ksi) and a tensile strength of 960 MPa (139 ksi) — stronger than 82% of titanium grades. Elongation at break is 16% and the elastic modulus is 105 GPa (15.2 Msi).
What is Ti-5553 used for?
- Aerospace landing gear forgings
- High-strength airframe fasteners
- Wing-to-body and pylon fittings
- Actuator components and pistons
- Slat and flap track structures
- Machined structural clevises and lugs
- Landing gear side stays and braces
Advantages
- High strength — 900 MPa (131 ksi), better than 82% of titanium grades
- Tough — resists crack growth — 80 MPa·√m (72.8 ksi·√in), better than 81% of titanium grades
Limitations
- Hard to polish — 60/100, worse than 97% of titanium grades
- Difficult to weld — 35/100, worse than 96% of titanium grades
Ti-5553 properties
Typical room-temperature values for Ti-5553-O; bars are the position among titanium grades.
Physical3
Ti-5553 has a density of 4.65 g/cm³ (0.168 lb/in³), heavier than 90% of titanium grades. It melts at 1,580°C (2,876 °F).
Mechanical16
Ti-5553 has a yield strength of 900 MPa (131 ksi) and a tensile strength of 960 MPa (139 ksi) — stronger than 82% of titanium grades. Elongation at break is 16% and the elastic modulus is 105 GPa (15.2 Msi).
Thermal6
Ti-5553 is rated for continuous service to 300°C (572 °F). It conducts heat at 7 W/m·K (4.04 BTU/hr·ft·°F), worse than 76% of titanium grades. Thermal expansion is 9.3 µm/m·K (5.17 µin/in·°F).
Electrical3
Ti-5553 conducts electricity at 1.1 % IACS, worse than 67% of titanium grades.
Chemical & Environmental3
Corrosion resistance is excellent (88/100), worse than 77% of titanium grades.
Sustainability4
Producing a kilogram of Ti-5553 takes about 650 MJ of energy and emits 42 kg of CO₂ — less than 75% of titanium grades. Typical recycled content is 25%.
Manufacturability8
Ti-5553's machinability is poor (16/100, worse than 93% of titanium grades); weldability fair (35/100); formability poor (30/100).
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. Ti-5553 is highlighted; hover a dot for its name, or open the interactive family chart.
Working with Ti-5553
Is Ti-5553 easy to machine?
Very difficult: rigid setups, sharp uncoated-carbide or PVD-coated tools, low surface speed (15–30 m/min aged), heavy feed, high-pressure flood coolant, no dwelling — rough machine in ST condition and finish after aging with light depth to avoid white layer.
Can Ti-5553 be welded?
GTAW/plasma/EB weldable with full inert-gas or vacuum shielding and matching filler, but the HAZ loses aged strength; post-weld solution treat plus age is normally required, so welding is avoided on primary structure.
Can Ti-5553 be formed, bent or molded?
Forge and hot-form just below the β transus (~805–855 °C) with tight temperature control to set α morphology; cold forming is impractical except mild bending in the solution-treated condition.
Manufacturability
The process limits FabDigit's quote engine applies to Ti-5553. Design inside these and the part quotes instantly; outside them it routes to an engineer.
CNC machining
| Machinability | Fair16 / 100 |
|---|---|
| ISO material group | S.3 |
| Cutting speed (rough / finish) | 60 / 75 m/min |
| Minimum wall | 1 mm |
| Minimum internal radius | 1.5 mm |
| Drill depth limit | 4× diameter |
| Best surface (machined / polished) | Ra 1.6 / — |
| Hardenable after machining | No |
Sheet metal
| Formability | Better30 / 100 |
|---|---|
| Weldability | Fair35 / 100 |
| Bendable | Yes |
Ti-5553 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 |
|---|---|---|
| Alα-stabiliser | 4.4 – 5.7 | 5 |
| V | 4 – 5.5 | 5 |
| Mo | 4 – 5.5 | 5 |
| Cr | 2.5 – 3.5 | 3 |
| Feintentional β-stabiliser addition | 0.3 – 0.5 | 0.4 |
| Ointerstitial, controls strength | 0.1 – 0.18 | 0.15 |
| C | ≤ 0.04 | |
| N | ≤ 0.05 | |
| Hmax (0.0125 typical for forgings) | ≤ 0.02 | |
| Y | ≤ 0.01 | |
| Other, eachresiduals, total 0.40 max | ≤ 0.1 | |
| Ti | balance |
What surface finishes work on Ti-5553?
Grit-blast/pickle (HNO₃–HF) to remove alpha case after hot work, shot peen for fatigue life; titanium anodise (AMS 2488) or ion-plating/dry-film lube for fretting and galling; never plate cadmium and avoid chlorinated cleaners before heat treatment.
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).
Passivation
Conversion Coating
Organic Coating
CVD Coating
Thermal Spray
Equivalent designations
Standards and trade names that resolve to Titanium Ti-5553 in FabDigit's catalog. Equivalence is nominal — check the exact specification when certification matters.
- UNS
- R58553
How much does Ti-5553 cost?
Ti-5553 is a specialty-cost titanium ($$$$$), pricier than about 99% 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.
Ti-5553 — frequently asked
What is Ti-5553 used for?
Ti-5553 is typically used for aerospace landing gear forgings, high-strength airframe fasteners, wing-to-body and pylon fittings, actuator components and pistons, slat and flap track structures and machined structural clevises and lugs. In short: premium β-titanium forging.
What is the yield strength of Ti-5553?
Ti-5553 has a typical yield strength of 900 MPa (131 ksi) and a tensile strength of 960 MPa (139 ksi) — stronger than 82% of titanium grades. Strength varies by condition: see the 7 listed tempers.
Is Ti-5553 easy to machine?
Not especially — machinability is rated poor (16/100, worse than 93% of titanium grades). Very difficult: rigid setups, sharp uncoated-carbide or PVD-coated tools, low surface speed (15–30 m/min aged), heavy feed, high-pressure flood coolant, no dwelling — rough machine in ST condition and finish after aging with light depth to avoid white layer.
Can Ti-5553 be welded?
With care — weldability is rated fair (35/100). GTAW/plasma/EB weldable with full inert-gas or vacuum shielding and matching filler, but the HAZ loses aged strength; post-weld solution treat plus age is normally required, so welding is avoided on primary structure.
What surface finishes work on Ti-5553?
Grit-blast/pickle (HNO₃–HF) to remove alpha case after hot work, shot peen for fatigue life; titanium anodise (AMS 2488) or ion-plating/dry-film lube for fretting and galling; never plate cadmium and avoid chlorinated cleaners before heat treatment.
Can Ti-5553 be formed, bent or molded?
Forge and hot-form just below the β transus (~805–855 °C) with tight temperature control to set α morphology; cold forming is impractical except mild bending in the solution-treated condition.
What is the maximum service temperature of Ti-5553?
Ti-5553 is rated for continuous use to about 300°C (572 °F). Strength falls off well before that limit — check the elevated-temperature data for load-bearing parts.
What is the difference between Ti-5553-O and Ti-5553 STA-HS?
O is the default condition — standard as-supplied mill condition for bar, billet and forging stock; balanced strength and ductility before final aging. STA-HS: choose when peak strength matters more than toughness (small, low-K-critical parts, fasteners, actuator components). Yield strength is 900 MPa in O versus 1,240 MPa in STA-HS.
How much does Ti-5553 cost?
Ti-5553 is a specialty-cost titanium ($$$$$), pricier than about 99% 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.
Can FabDigit make parts in Ti-5553?
Yes — Ti-5553 is available for CNC machining and sheet metal with instant online pricing. Upload a STEP file to get a price and a DFM check.
Sources
- AMS 6932 — Titanium Alloy Forgings, 5Al-5V-5Mo-3Cr — SAE International (2018)
- AMS 4983 — Ti-5Al-5V-5Mo-3Cr Bar and Billet — SAE International (2017)
- ASM Handbook Vol. 2 — Properties and Selection: Nonferrous Alloys — ASM International (1990)
- Titanium: A Technical Guide, 2nd ed. (metastable β alloys) — ASM International (2000)
- Ti-5Al-5V-5Mo-3Cr (Ti-5553) alloy data — TIMET / VSMPO-AVISMA (2020)
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.