Grade 7 Titanium Alloy | Ti-0.2Pd | UNS R52400 | ASTM B265 / B348 Supplier
Supplied by Huaxiao-Alloy – Your Trusted Global Alloy Partner
1. Grade 7 Titanium Alloy (Ti-0.2Pd) Overview
Grade 7 Titanium Alloy, designated as Ti-0.2Pd, is a palladium-enhanced commercially pure titanium alloy specifically engineered to deliver exceptional corrosion resistance in highly aggressive chemical environments.
By adding approximately 0.12–0.25% palladium (Pd) to commercially pure titanium (similar base to Grade 2), Grade 7 achieves dramatically improved resistance to reducing acids, crevice corrosion, and corrosion under low pH or stagnant conditions, while maintaining the excellent formability, weldability, and toughness of CP titanium.
Because of this unique balance, Grade 7 is widely regarded as the most corrosion-resistant titanium grade commonly available, making it a preferred material for chemical processing, offshore engineering, power generation, and desalination systems.
As a reliable Grade 7 titanium alloy supplier, Huaxiao-Alloy provides UNS R52400 Ti-0.2Pd in full mill product forms, manufactured strictly according to ASTM, ASME, AMS, ISO, and EN standards, with complete certification and global export capability.
2. Equivalent Standards & Designations
Grade 7 titanium alloy is internationally standardized and universally accepted in corrosion-critical industries.
| Standard System | Designation |
|---|---|
| ASTM | Grade 7 (Ti-0.2Pd) |
| UNS | R52400 |
| ASME | SB-265 / SB-348 |
| AMS | AMS 4957 (related forms) |
| ISO | ISO 5832 (corrosion service reference) |
| DIN / EN | 3.7235 (related Pd-alloyed Ti) |
| JIS | Class 7 Titanium |
| GB (China) | TA7 |
➡️ These equivalents allow Grade 7 titanium to be specified seamlessly in global EPC, chemical plant, and offshore projects.
3. Chemical Composition of Grade 7 Titanium Alloy
Grade 7 is essentially commercially pure titanium with palladium addition, giving it superior electrochemical stability.
| Element | Content (%) |
|---|---|
| Titanium (Ti) | Balance |
| Palladium (Pd) | 0.12 – 0.25 |
| Iron (Fe) | ≤ 0.30 |
| Oxygen (O) | ≤ 0.25 |
| Carbon (C) | ≤ 0.08 |
| Nitrogen (N) | ≤ 0.03 |
| Hydrogen (H) | ≤ 0.015 |
Composition Insight
Palladium significantly enhances resistance to reducing acids
Promotes rapid repassivation of titanium oxide film
Allows titanium to perform reliably in environments where CP grades fail
4. Mechanical Properties of Ti-0.2Pd (Grade 7)
4.1 Mechanical Properties at Room Temperature (Annealed)
| Property | Typical Value |
|---|---|
| Tensile Strength | ≥ 345 MPa |
| Yield Strength (0.2%) | ≥ 275 MPa |
| Elongation | ≥ 20% |
| Hardness | ~ 160 HB |
| Density | 4.51 g/cm³ |
| Elastic Modulus | ~105 GPa |
4.2 Mechanical Characteristics
Mechanical properties similar to Grade 2 titanium
Lower strength than alloyed grades (Grade 5/6)
Excellent ductility and toughness
Ideal for forming complex corrosion-resistant equipment
5. Key Features & Advantages of Grade 7 Titanium Alloy
5.1 Outstanding Corrosion Resistance (Core Advantage)
Grade 7 demonstrates exceptional performance in aggressive media, including:
Reducing acids (sulfuric, hydrochloric)
Mixed acid systems
Chloride-rich environments
Low-pH and stagnant conditions
➡️ In many cases, Grade 7 replaces expensive nickel alloys at lower lifecycle cost.
5.2 Superior Resistance to Crevice & Pitting Corrosion
Palladium addition lowers hydrogen overpotential
Enhances repassivation under oxygen-depleted conditions
Ideal for:
Heat exchanger tube sheets
Flanged connections
Gasketed joints
5.3 Excellent Weldability & Fabrication
Weldability similar to CP titanium
No post-weld heat treatment required in most cases
Stable corrosion performance across weld zones
5.4 Long Service Life & Low Maintenance
Minimal corrosion allowance needed
Low inspection and replacement frequency
Excellent ROI for chemical and offshore plants
6. Available Product Forms from Huaxiao-Alloy
Huaxiao-Alloy supplies Grade 7 Ti-0.2Pd in a full range of mill and fabricated products.
6.1 Titanium Sheets & Plates
Standard: ASTM B265 / ASME SB-265
Thickness: 0.5 mm – 60 mm
Surface: Pickled, annealed
6.2 Titanium Pipes & Tubes
Standard: ASTM B861 / B338
Seamless & welded
OD: 6 mm – 219 mm
6.3 Titanium Bars & Rods
Standard: ASTM B348
Round, square, flat
Hot-forged or cold-drawn
6.4 Titanium Wire & Strip
Diameter: 0.2 mm – 6.0 mm
For corrosion-resistant fasteners & welding wire
6.5 Titanium Forgings & Custom Parts
Tube sheets
Flanges
Heat exchanger components
OEM machining to drawings
7. Typical Applications of Grade 7 Titanium Alloy
7.1 Chemical Processing Industry
Reactors
Heat exchangers
Condensers
Acid handling systems
7.2 Oil, Gas & Offshore Engineering
Seawater piping systems
Subsea equipment
Offshore heat exchangers
7.3 Power Generation & Desalination
Condenser tubing
Brine heaters
Evaporators
7.4 Pulp & Paper Industry
Bleaching equipment
Chloride-rich process systems
7.5 Environmental & Pollution Control
Scrubbers
Waste treatment equipment
Acid recovery systems
8. Corrosion Resistance Performance (Detailed)
8.1 Acid Resistance Comparison
| Medium | Grade 2 | Grade 7 |
|---|---|---|
| Dilute H₂SO₄ | Moderate | Excellent |
| Dilute HCl | Poor | Good–Excellent |
| Nitric Acid | Excellent | Excellent |
| Chlorides | Excellent | Excellent |
8.2 Why Palladium Works
Acts as a noble metal catalyst
Promotes rapid hydrogen evolution
Stabilizes passive TiO₂ layer
Prevents localized corrosion initiation
9. Fabrication, Machining & Welding Guide
9.1 Forming
Excellent cold and hot formability
Suitable for deep drawing and rolling
Low springback compared to alloyed grades
9.2 Machining
Similar to CP titanium
Low cutting speeds required
Sharp tools and proper cooling essential
9.3 Welding
TIG, MIG, plasma welding recommended
Full argon shielding required
Weld corrosion resistance remains intact
10. Heat Resistance & Thermal Properties
Maximum service temperature: ~300°C (corrosion service)
Excellent thermal stability
Low thermal expansion
Not designed for high-load high-temperature structural use
11. Comparison: Grade 2 vs Grade 7 Titanium
| Property | Grade 2 | Grade 7 |
|---|---|---|
| Strength | Moderate | Moderate |
| Corrosion Resistance | Excellent | Outstanding |
| Reducing Acid Resistance | Poor–Moderate | Excellent |
| Cost | Lower | Higher |
| Typical Use | General corrosion | Severe corrosion |
12. Quality Assurance & Certifications
All Grade 7 titanium supplied by Huaxiao-Alloy includes:
EN 10204 3.1 / 3.2 Mill Test Certificate
Full chemical & mechanical analysis
PMI testing available
Ultrasonic & eddy current inspection
ISO 9001 quality system
Complete heat number traceability
13. Why Choose Huaxiao-Alloy as Your Grade 7 Titanium Supplier?
✅ Strong expertise in corrosion-resistant titanium
✅ Long-term supply to chemical & offshore projects
✅ Full product range + custom fabrication
✅ Competitive pricing vs nickel alloys
✅ Fast global logistics
✅ Professional export documentation support
Yes, significantly better, especially in reducing acids.
In many corrosion environments, yes—at lower lifecycle cost.
Yes, weldability is excellent with proper shielding.
No, it is completely non-magnetic.
Yes, full machining and fabrication services are available.
TItanium Products
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