Grade 6 Titanium Alloy | Ti-5Al-2.5Sn | UNS R55250 | ASTM B348 Supplier
Supplied by Huaxiao-Alloy – Your Trusted Global Alloy Partner
1. Grade 6 Titanium Alloy (Ti-5Al-2.5Sn) Overview
Grade 6 Titanium Alloy, also designated as Ti-5Al-2.5Sn, is a near-alpha titanium alloy specifically developed for high-temperature structural applications where creep resistance, thermal stability, and long-term mechanical reliability are critical.
Unlike Grade 5 (Ti-6Al-4V), which is an α-β alloy optimized for room-temperature strength, Grade 6 is designed to retain strength and stability at elevated temperatures up to approximately 400–450°C. This makes it a preferred material for aerospace engine components, hot airframe structures, and high-temperature pressure systems.
As a professional Grade 6 titanium alloy supplier, Huaxiao-Alloy supplies UNS R55250 Ti-5Al-2.5Sn in full mill forms, produced in strict accordance with ASTM, AMS, ISO, and EN standards, serving aerospace, defense, marine, and energy industries worldwide.
2. Equivalent Standards & Designations
Grade 6 titanium alloy is internationally standardized and widely accepted across aerospace and industrial systems.
| Standard System | Designation |
|---|---|
| ASTM | Grade 6 (Ti-5Al-2.5Sn) |
| UNS | R55250 |
| AMS | AMS 4904 / AMS 4910 / AMS 4911 |
| ISO | ISO 5832-2 (related applications) |
| DIN / EN | 3.7164 (related near-alpha grades) |
| JIS | TAP6400-equivalent |
| GB (China) | TA6 / TC6 (industry equivalent) |
➡️ These equivalents ensure smooth cross-border engineering approval and procurement.
3. Chemical Composition of Grade 6 Titanium Alloy
Grade 6 is a near-alpha titanium alloy, strengthened primarily by aluminum and tin, without beta stabilizers such as vanadium.
| Element | Content (%) |
|---|---|
| Titanium (Ti) | Balance |
| Aluminum (Al) | 4.5 – 5.5 |
| Tin (Sn) | 2.0 – 3.0 |
| Iron (Fe) | ≤ 0.30 |
| Oxygen (O) | ≤ 0.20 |
| Carbon (C) | ≤ 0.08 |
| Nitrogen (N) | ≤ 0.05 |
| Hydrogen (H) | ≤ 0.015 |
Composition Insight
Aluminum improves strength and oxidation resistance
Tin enhances creep resistance and thermal stability
Absence of vanadium improves high-temperature reliability
4. Mechanical Properties of Ti-5Al-2.5Sn
4.1 Mechanical Properties at Room Temperature (Annealed)
| Property | Typical Value |
|---|---|
| Tensile Strength | ≥ 828 MPa |
| Yield Strength (0.2%) | ≥ 758 MPa |
| Elongation | ≥ 10% |
| Hardness | ~ 300 HB |
| Density | 4.48 g/cm³ |
| Elastic Modulus | ~110 GPa |
4.2 High-Temperature Performance
Maintains mechanical integrity at 400–450°C
Excellent creep resistance under long-term thermal load
Stable microstructure during prolonged service
5. Key Features & Advantages of Grade 6 Titanium Alloy
5.1 Superior High-Temperature Stability
Grade 6 outperforms Grade 5 in:
Creep resistance
Thermal fatigue resistance
Long-term dimensional stability
5.2 Excellent Strength-to-Weight Ratio
Much stronger than CP titanium grades
Comparable strength to high-strength steels at ~60% weight
5.3 Outstanding Corrosion Resistance
Resistant to marine atmospheres and seawater
Excellent performance in oxidizing environments
Stable passive oxide film
5.4 Good Weldability & Fabricability
Better weld stability than α-β alloys
Reduced risk of beta phase embrittlement
Suitable for pressure vessels and welded structures
6. Available Product Forms from Huaxiao-Alloy
Huaxiao-Alloy supplies Grade 6 Ti-5Al-2.5Sn in complete product forms.
6.1 Titanium Sheets & Plates
Standards: ASTM B265 / AMS 4910
Thickness: 0.8 mm – 80 mm
Condition: Annealed / Stress relieved
6.2 Titanium Pipes & Tubes
Standards: ASTM B861 / B338
Seamless preferred for aerospace
OD: 6 mm – 168 mm
6.3 Titanium Bars & Rods
Standard: ASTM B348
Round / square / hex
Hot-rolled and forged
6.4 Titanium Forgings
Rings, discs, structural forgings
Aerospace-grade forging capability
Custom shapes per drawing
7. Typical Applications of Grade 6 Titanium Alloy
7.1 Aerospace & Aviation
Engine casings
Compressor components
Hot airframe structures
7.2 Marine & Offshore Engineering
High-temperature seawater systems
Offshore structural parts
Corrosion-resistant fasteners
7.3 Power & Energy Industry
Heat exchangers
Gas turbine components
Thermal system piping
7.4 Defense & Military Equipment
Missile structures
Aircraft support systems
High-reliability welded assemblies
8. Corrosion Resistance Performance
Grade 6 titanium alloy exhibits corrosion resistance similar to CP titanium:
✔ Resistant to:
Seawater and marine atmospheres
Chloride-containing environments
Oxidizing acids (nitric acid)
❌ Limited resistance to:
Hot reducing acids
High-temperature halogen environments
9. Fabrication, Machining & Welding Guide
9.1 Forming
Better hot formability than Grade 5
Hot forming recommended for thick sections
Lower springback than α-β alloys
9.2 Machining
Lower cutting speeds recommended
Sharp carbide tools required
Efficient cooling essential
9.3 Welding
Excellent weldability with argon shielding
TIG and plasma welding preferred
Minimal post-weld heat treatment required
10. Heat Resistance & Thermal Properties
Maximum continuous service temperature: ~450°C
Excellent oxidation resistance
Low thermal expansion
High resistance to thermal fatigue
11. Comparison: Grade 5 vs Grade 6 Titanium Alloy
| Property | Grade 5 (Ti-6Al-4V) | Grade 6 (Ti-5Al-2.5Sn) |
|---|---|---|
| Alloy Type | α-β | Near-α |
| Room-Temp Strength | Higher | Slightly Lower |
| High-Temp Stability | Moderate | Excellent |
| Creep Resistance | Moderate | Superior |
| Typical Use | General aerospace | High-temp aerospace |
12. Quality Assurance & Certifications
All Grade 6 titanium from Huaxiao-Alloy includes:
EN 10204 3.1 / 3.2 MTC
Full chemical & mechanical testing
Ultrasonic & surface inspection
ISO 9001 quality system
Heat number traceability
13. Why Choose Huaxiao-Alloy as Your Grade 6 Titanium Supplier?
✅ Deep expertise in titanium & special alloys
✅ Aerospace-grade production lines
✅ Stable export to EU, North America, Middle East
✅ Competitive pricing for bulk orders
✅ Custom forging & machining support
✅ Fast, reliable global logistics
No, but it performs better at high temperatures.
Only in high-temperature applications where creep resistance is critical.
Yes, it has excellent weld stability.
Yes, corrosion resistance is excellent.
Yes, full custom forging service is available.
TItanium Products
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