Overview
Grade 3 Titanium is a commercially pure titanium alloy that offers a unique balance of high strength, excellent corrosion resistance, good weldability, and moderate formability. Classified as UNS R50550, Grade 3 provides significantly higher strength than Grade 1 and Grade 2 titanium while retaining the outstanding corrosion resistance characteristic of commercially pure titanium grades.
Although less commonly used than Grade 2, Grade 3 is selected for applications requiring greater load-bearing capability without transitioning to alloyed titanium grades such as Grade 5.
Grade 3 titanium is widely used in:
- Aerospace Components
- Chemical Processing Equipment
- Pressure Vessels
- Heat Exchangers
- Marine Equipment
- Medical Devices
- Desalination Systems
- Industrial Machinery
Because of its combination of strength and corrosion resistance, Grade 3 is frequently specified for demanding industrial environments.
Material Specification
| Property | Value |
|---|---|
| Material Designation | Grade 3 Titanium |
| UNS Number | R50550 |
| ASTM Standard | ASTM B265 / ASTM B348 / ASTM B381 |
| Material Family | Commercially Pure Titanium |
| Density | 4.51 g/cm³ |
| Magnetic Property | Non-Magnetic |
| Typical Supply Condition | Annealed |
| Standard Forms | Sheet, Plate, Bar, Rod, Tube, Pipe, Wire |
Chemical Composition
| Element | Content (%) |
|---|---|
| Titanium (Ti) | Balance |
| Oxygen (O) | ≤0.35 |
| Iron (Fe) | ≤0.30 |
| Carbon (C) | ≤0.08 |
| Nitrogen (N) | ≤0.05 |
| Hydrogen (H) | ≤0.015 |
The increased oxygen content compared with Grade 1 and Grade 2 provides enhanced strength.
Mechanical Properties
Annealed Condition
| Property | Value |
|---|---|
| Tensile Strength | ≥450 MPa |
| Yield Strength | ≥380 MPa |
| Elongation | ≥18% |
| Hardness | 160–200 HB |
| Elastic Modulus | 105 GPa |
Typical Mechanical Performance
| Property | Value |
|---|---|
| Fatigue Resistance | Very Good |
| Impact Toughness | Excellent |
| Ductility | Good |
| Formability | Good |
Physical Properties
| Property | Value |
|---|---|
| Density | 4.51 g/cm³ |
| Melting Point | 1668°C |
| Thermal Conductivity | 16.0 W/m·K |
| Electrical Conductivity | 3% IACS |
| Electrical Resistivity | 0.57 μΩ·m |
| Thermal Expansion Coefficient | 8.6 × 10⁻⁶/K |
| Specific Heat Capacity | 523 J/kg·K |
Strength-to-Weight Ratio
| Material | Density (g/cm³) | Tensile Strength |
|---|---|---|
| Grade 3 Titanium | 4.51 | 450 MPa |
| Grade 2 Titanium | 4.51 | 345 MPa |
| Grade 1 Titanium | 4.51 | 240 MPa |
| Stainless Steel 316L | 8.00 | 485 MPa |
Grade 3 offers substantially higher strength than other commercially pure titanium grades while maintaining a low density.
Corrosion Resistance
| Environment | Performance |
|---|---|
| Fresh Water | Excellent |
| Salt Water | Excellent |
| Marine Atmosphere | Excellent |
| Chloride Solutions | Excellent |
| Oxidizing Acids | Excellent |
| Chemical Processing | Excellent |
Grade 3 titanium provides corrosion resistance nearly identical to Grade 1 and Grade 2.
Recommended surface treatments:
- Pickling
- Passivation
- Polishing
- Anodizing
- Electropolishing
Weldability
| Welding Process | Rating |
|---|---|
| TIG Welding | Excellent |
| MIG Welding | Excellent |
| Resistance Welding | Excellent |
| Laser Welding | Excellent |
Grade 3 maintains excellent weldability despite its higher strength.
Machinability
| Process | Rating |
|---|---|
| CNC Turning | Moderate |
| CNC Milling | Moderate |
| Drilling | Moderate |
| Grinding | Good |
| Forming | Good |
Machinability Comparison
| Material | Machinability |
|---|---|
| Aluminum 6061 | Excellent |
| Stainless Steel 304 | Moderate |
| Grade 3 Titanium | Moderate |
| Grade 5 Titanium | Difficult |
As with all titanium grades, proper tooling and cooling are important during machining.
Heat Treatment
Stress Relief
| Parameter | Value |
|---|---|
| Temperature | 480–650°C |
| Cooling Method | Air Cool |
Annealing
| Parameter | Value |
|---|---|
| Temperature | 650–760°C |
| Cooling Method | Air Cool |
Heat Treatability
| Property | Performance |
|---|---|
| Heat Treat Hardening | No |
| Annealing Response | Excellent |
| Cold Work Strengthening | Limited |
Grade 3 titanium is strengthened primarily through composition control rather than heat treatment.
International Equivalent Grades
| Standard | Equivalent Grade |
|---|---|
| ASTM (USA) | Grade 3 |
| UNS | R50550 |
| DIN (Germany) | 3.7055 |
| EN (Europe) | Titanium Grade 3 |
| ISO | Titanium Grade 3 |
| JIS (Japan) | Class 3 Titanium |
| GB/T (China) | TA3 |
Available Forms
| Product Type | Availability |
|---|---|
| Sheet | Yes |
| Plate | Yes |
| Round Bar | Yes |
| Flat Bar | Yes |
| Tube | Yes |
| Pipe | Yes |
| Wire | Yes |
| Forgings | Yes |
Typical Applications
Chemical Processing Industry
- Pressure Vessels
- Heat Exchangers
- Reactor Components
- Chemical Piping
Marine Industry
- Seawater Systems
- Offshore Equipment
- Desalination Plants
- Marine Fasteners
Aerospace Industry
- Structural Components
- Hydraulic Systems
- Corrosion-Resistant Assemblies
Medical Industry
- Surgical Equipment
- Medical Hardware
- Laboratory Equipment
Energy Industry
- Power Generation Components
- Heat Recovery Systems
- Industrial Heat Exchangers
Industrial Manufacturing
- Pumps
- Valves
- Process Equipment
- Corrosion-Resistant Machinery
Manufacturing Characteristics
| Manufacturing Process | Rating |
|---|---|
| CNC Machining | Good |
| Forming | Good |
| Deep Drawing | Good |
| Welding | Excellent |
| Anodizing | Excellent |
| Polishing | Excellent |
Advantages
Higher Strength Than Grade 1 and Grade 2
Provides improved load-bearing capability.
Excellent Corrosion Resistance
Outstanding performance in marine and chemical environments.
Good Weldability
Suitable for complex welded structures.
Lightweight
Approximately 45% lighter than stainless steel.
Non-Magnetic
Suitable for medical and electronic applications.
Long Service Life
Excellent durability in aggressive operating conditions.
Limitations
Lower Formability Than Grade 1 and Grade 2
Higher strength reduces cold-forming capability.
Higher Material Cost
More expensive than stainless steel and aluminum.
Lower Strength Than Grade 5 Titanium
Not intended for highly stressed aerospace structures.
Poor Thermal Conductivity
Limited heat transfer capability compared with copper alloys.
Comparison with Other Titanium Grades
| Property | Grade 3 | Grade 2 | Grade 1 | Grade 5 |
|---|---|---|---|---|
| Strength | High | Moderate | Lower | Highest |
| Ductility | Good | Excellent | Outstanding | Moderate |
| Corrosion Resistance | Excellent | Excellent | Excellent | Excellent |
| Weldability | Excellent | Outstanding | Outstanding | Good |
| Formability | Good | Excellent | Outstanding | Moderate |
Comparison with Common Materials
| Material | Density | Corrosion Resistance | Strength |
|---|---|---|---|
| Grade 3 Titanium | 4.51 g/cm³ | Excellent | High |
| Grade 2 Titanium | 4.51 g/cm³ | Excellent | Moderate |
| 316L Stainless Steel | 8.00 g/cm³ | Excellent | Similar |
| Aluminum 6061-T6 | 2.70 g/cm³ | Good | Lower |
Available Surface Finishes
Raw Finishes
- Mill Finish
- Annealed Finish
- Pickled Finish
Functional Finishes
- Precision Machined Finish
- Polished Finish
- Brushed Finish
Specialty Finishes
- Anodized Finish
- Electropolished Finish
- Medical Grade Finish
Frequently Asked Questions (FAQ)
What is Grade 3 titanium?
Grade 3 is a high-strength commercially pure titanium alloy offering excellent corrosion resistance and improved mechanical properties.
What is Grade 3 titanium used for?
Typical applications include:
- Pressure Vessels
- Heat Exchangers
- Aerospace Components
- Marine Equipment
- Chemical Processing Systems
What is the equivalent material to Grade 3 titanium?
Common equivalents include:
- UNS R50550
- DIN 3.7055
- TA3
- Titanium Grade 3
What is the difference between Grade 2 and Grade 3 titanium?
| Property | Grade 2 | Grade 3 |
|---|---|---|
| Strength | Lower | Higher |
| Ductility | Higher | Lower |
| Formability | Better | Good |
| Industrial Use | More Common | Specialized |
Is Grade 3 titanium corrosion resistant?
Yes. It offers exceptional resistance to seawater, chlorides, and aggressive chemicals.
Can Grade 3 titanium be welded?
Yes. Grade 3 maintains excellent weldability and fabrication performance.
Why choose Grade 3 titanium?
Because it combines:
- High Strength
- Excellent Corrosion Resistance
- Good Weldability
- Lightweight Performance
- Long Service Life
Is Grade 3 titanium suitable for pressure vessels?
Yes. Its higher strength makes it well suited for pressure-containing equipment.
Does GCNOV provide custom manufacturing services for Grade 3 titanium?
Yes. GCNOV provides:
- CNC Machining
- Titanium Fabrication
- Precision Welding
- Sheet Metal Forming
- Surface Finishing
- Prototype Development
- Low-Volume Production
- Mass Production