Commercially Pure Titanium Grade 2
Technical guide to Grade 2 commercially pure titanium — the most widely used CP titanium grade. Properties, chemical composition, machinability, and applications for industrial, chemical processing, and marine environments.
| Property | Value |
|---|---|
| Density | 4.51 g/cm³ |
| Tensile Strength | 345 MPa |
| Yield Strength | 275 MPa |
| Hardness | 24 HRC |
| Max Temp | 315°C |
Quick Answer
What is Grade 2 titanium?
Grade 2 is the most widely specified commercially pure (CP) titanium grade, containing 99.2% minimum titanium with trace amounts of iron, oxygen, carbon, nitrogen, and hydrogen. It offers an excellent balance of corrosion resistance, formability, weldability, and moderate strength — making it the default CP titanium for chemical processing equipment, marine components, heat exchangers, and architectural applications.
Chemical Composition
| Element | Weight % |
|---|---|
| Titanium (Ti) | balance (≥ 99.2%) |
| Iron (Fe) | ≤ 0.30 |
| Oxygen (O) | ≤ 0.25 |
| Carbon (C) | ≤ 0.08 |
| Nitrogen (N) | ≤ 0.03 |
| Hydrogen (H) | ≤ 0.015 |
Mechanical Properties
| Property | Value |
|---|---|
| Density | 4.51 g/cm³ |
| Tensile Strength | 345 MPa (min) |
| Yield Strength (0.2% offset) | 275 MPa (min) |
| Elongation | 20% |
| Hardness | 24 HRC |
| Modulus of Elasticity | 105 GPa |
| Max Service Temperature | 315°C |
| Melting Point | 1668°C |
Machinability
Grade 2 is the most machinable of the titanium grades due to its lower strength and higher ductility. It produces continuous chips and requires less cutting force than Grade 5. However, its gummy nature can lead to built-up edge formation if speeds and feeds are not optimised.
Recommended Cutting Parameters
| Operation | Speed (SFM) | Feed (IPT) | DOC |
|---|---|---|---|
| Rough Milling | 200–350 | 0.005–0.010 | 0.080–0.180 |
| Finish Milling | 300–450 | 0.003–0.006 | 0.010–0.040 |
| Turning | 250–400 | 0.006–0.015 | 0.050–0.150 |
| Drilling | 80–150 | 0.003–0.008 | — |
Key considerations:
- Use sharp carbide tooling with polished flutes to reduce built-up edge
- Apply high-pressure coolant (>1000 PSI) for chip evacuation
- Rigid fixturing is less critical than for Grade 5 but still recommended
- Thread forming rather than cutting produces stronger threads in CP grades
Typical Applications
- Chemical Processing: Heat exchangers, reaction vessels, piping systems, valves
- Marine: Propeller shafts, seawater piping, desalination plant components, hull fittings
- Industrial: Electrodes for electrowinning, anodes for cathodic protection, bleaching equipment
- Architectural: Building cladding, roofing, structural facades (corrosion-resistant aesthetic)
- Energy: Geothermal well casings, condenser tubing in power plants
- Medical: Surgical instruments (non-implant), instrument trays
- Aerospace: Non-structural airframe components, hydraulic tubing, ducting
Related Standards
- ASTM B265 — Titanium and Titanium Alloy Strip, Sheet, and Plate
- ASTM B348 — Titanium and Titanium Alloy Bars and Billets
- ASTM B381 — Titanium and Titanium Alloy Forgings
- ASTM B861 — Titanium and Titanium Alloy Seamless Pipe
- ASTM B862 — Titanium and Titanium Alloy Welded Pipe
- ISO 5832-2 — Implants for Surgery — Unalloyed Titanium
Related Processes
- CNC Machining — Grade 2 machines readily with standard carbide tooling
- Sheet Metal Forming — Excellent ductility supports deep drawing, bending, and hydroforming
- Welding — TIG and MIG weldable with proper shielding; filler metal typically same grade
- Anodizing — Produces protective oxide layer; colour anodizing possible with voltage control
- Passivation — Enhances native corrosion resistance for chemical and medical applications