Titanium Grade 3 is a higher-strength commercially pure titanium grade positioned between Grades 2 and 4.
It retains the excellent corrosion resistance associated with commercially pure titanium while providing greater tensile and yield strength than Grades 1 and 2.
Grade 3 is designated UNS R50550. The increased strength primarily results from tighter control at higher permitted levels of interstitial elements, particularly oxygen, rather than from conventional alloy additions.
Grade 3 Chemical Composition
| Element | Weight % |
|---|---|
| Titanium (Ti) | Balance |
| Oxygen (O) | ≤ 0.35 |
| Iron (Fe) | ≤ 0.30 |
| Carbon (C) | ≤ 0.08 |
| Nitrogen (N) | ≤ 0.05 |
| Hydrogen (H) | ≤ 0.015 |
Grade 3 Mechanical Properties
Representative minimum annealed properties are:
| Property | Value |
|---|---|
| Ultimate tensile strength | ≥ 450 MPa |
| 0.2% yield strength | ≥ 380 MPa |
| Elongation | ≥ 18% |
| Density | approximately 4.51 g/cm³ |
These are specification-style minimums rather than guaranteed values for every product configuration.
Characteristics
Grade 3 provides greater load-carrying capability than Grade 2 while retaining useful ductility, weldability and corrosion resistance.
Compared with Grade 2, forming operations generally require greater force and larger bend radii because of Grade 3’s higher strength.
Typical Applications
- Pressure vessels
- Chemical-process equipment
- Heat exchangers
- Piping systems
- Marine components
- Industrial structures
- Aerospace components requiring commercially pure titanium with increased strength
- Medical applications covered by an appropriate Grade 3 specification
Common Specifications
- ASTM B265
- ASTM B348
- ASTM F67
- ASME SB-265
- AMS 4900 for applicable sheet, strip and plate products
Technical Note
Chemical and mechanical properties shown are representative of commonly referenced specifications. Requirements can vary by product form, thickness, heat treatment and governing standard. Material should be ordered to the required specification, and the supplied material test report (MTR) should be used to verify compliance.
