Ti Grade 2 (CP) vs Ti-6Al-4V (Grade 5)
Ti Grade 2 and Ti-6Al-4V represent the two main families of titanium. Grade 2 is commercially pure (CP) titanium, valued for formability and corrosion resistance at modest strength. Ti-6Al-4V (Grade 5) is an alpha-beta alloy delivering far higher strength and the best strength-to-weight ratio. The decision usually weighs Grade 2's formability and lower cost against the alloy's much greater strength.
The verdict
Choose Grade 2 for corrosion-critical, formable parts like heat exchangers, piping, and sheet fabrications where moderate strength suffices. Choose Ti-6Al-4V when you need high strength and the best strength-to-weight ratio for aerospace, medical, and high-stress structural parts, accepting harder machining and higher cost.
Side-by-side data
| Property | Ti Grade 2 (CP) | Ti-6Al-4V (Grade 5) |
|---|---|---|
| Category | Titanium | Titanium |
| Density (g/cm³) | 4.51 | 4.43 |
| Tensile strength (MPa) | 485 | 1000 |
| Yield strength (MPa) | 380 | 910 |
| Elongation (%) | 20 | 14 |
| Hardness | 200 HB | 36 HRC |
| Max service temp (°C) | 425 | 400 |
| Machinability | ●●●●● | ●●●●● |
| Corrosion resistance | ●●●●● | ●●●●● |
| Relative cost | ●●●●● | ●●●●● |
| Thermal cond. (W/m·K) | 17 | 6.7 |
| Typically used for | Corrosion-critical, formable titanium | Aerospace & medical — best strength-to-weight |
Which should you choose?
Choose Ti Grade 2 (CP) when…
- The part is formed sheet, tube, or plate needing good workability
- Excellent corrosion resistance (rating 5.0) drives the choice
- Moderate strength (~485 MPa tensile) is sufficient for the load
- Higher elongation (~20%) supports bending and forming
- Easier machining (2.0 vs 6Al-4V's 1.5) speeds production
- Heat exchangers, chemical piping, or marine fittings are involved
Choose Ti-6Al-4V (Grade 5) when…
- High strength (~1000 MPa tensile, ~910 MPa yield) is required
- Best strength-to-weight ratio is the governing design driver
- The part is aerospace, medical, or a high-stress structural component
- Heat-treatable alpha-beta alloy properties are needed
- Weight savings at high load justify the higher cost (5.0 index)
- Both strength and titanium's full corrosion resistance (5.0) are essential
Key differences that matter
- Grade 2 is commercially pure titanium; Ti-6Al-4V is an alpha-beta alloy with ~6% aluminum and ~4% vanadium
- Ti-6Al-4V is roughly twice as strong (tensile ~1000 vs 485 MPa, yield ~910 vs 380 MPa) for high-stress use
- Grade 2 is more formable and ductile (elongation ~20% vs 14%), suiting sheet and tube fabrication
- Both share titanium's maximum corrosion resistance (rating 5.0) in chemical and marine environments
- Ti-6Al-4V is heat-treatable to higher strength; CP Grade 2 is not significantly hardenable by heat treatment
- Grade 2 machines somewhat more easily (2.0 vs 1.5), though both are challenging compared with steel
- Ti-6Al-4V is denser-efficient for strength-to-weight; cost is higher (5.0 vs Grade 2's 4.5)
Need Ti Grade 2 (CP) or Ti-6Al-4V (Grade 5) parts made?
Use our free tools to finalize your spec, then get a quote from a vetted factory.
Open the Material SelectorGet a Quote →Frequently asked questions
How much stronger is Ti-6Al-4V than Grade 2?
Substantially. In this data Ti-6Al-4V reaches about 1000 MPa tensile and 910 MPa yield, roughly double Grade 2's 485 and 380 MPa. That added strength comes from its aluminum and vanadium alloying and heat-treatability, making 6Al-4V the choice for high-stress aerospace and structural parts where CP titanium would be too weak.
Why pick Grade 2 if 6Al-4V is stronger?
Grade 2 is far more formable, easier to machine and weld, and lower cost. For corrosion-critical fabrications like heat exchangers, chemical piping, and sheet parts, its moderate strength is plenty, and its higher ductility makes forming straightforward. You only pay for 6Al-4V's strength when the application actually demands it.
Do both resist corrosion equally?
Yes, essentially. Both carry the maximum corrosion rating of 5.0, resisting seawater, many acids, and oxidizing media through titanium's stable passive oxide film. Corrosion performance is not the deciding factor between them; the choice is driven by the strength, formability, machinability, and cost differences instead.
Is Ti-6Al-4V harder to machine than Grade 2?
Yes. Ti-6Al-4V rates 1.5 on machinability versus Grade 2's 2.0, and both are demanding compared with steel. The alloy's higher strength and low thermal conductivity concentrate heat at the tool edge, so it requires rigid setups, sharp tooling, flood coolant, and conservative speeds to avoid work hardening and tool wear.
Property values are typical/nominal figures for early-stage guidance only and vary by temper, grade, supplier and heat treatment. Confirm critical specifications against a certified datasheet or with an mfgiq engineer before production.