A buyer sends an RFQ for a titanium reactor vessel. The supplier quotes it back asking one question first: “Gr2 or Gr5?” The buyer picked Gr5 because it was the grade they’d heard of — it sounded like the stronger, more serious choice. Two weeks later, after the quote came back roughly 40% higher than expected and the mill flagged a longer lead time for the thicker-gauge forming, the buyer asked us why. The answer wasn’t that Gr5 was wrong — it’s that nobody had asked what the part actually needed to do.
The difference isn’t “better,” it’s “different”
Gr2 is commercially pure titanium — no significant alloying elements. Gr5 (Ti-6Al-4V) is an alloy, roughly 6% aluminum and 4% vanadium added to the base metal. That single change is what separates them, and it cuts both ways: Gr5 gains strength and loses corrosion resistance, formability, and machinability. Gr2 does the reverse — and it’s the first thing to pin down before you put together an RFQ, since the grade changes the tolerance, lead time, and price a supplier can quote.
Neither one is the upgrade. They’re built for different jobs.
Gr2 vs Gr5, side by side
| Gr2 (commercially pure) | Gr5 / Ti-6Al-4V | |
|---|---|---|
| Composition | Unalloyed titanium | ~6% aluminum, ~4% vanadium |
| Tensile strength | Lower (general baseline ~345 MPa min per ASTM B348) | Roughly double Gr2 (~895 MPa min per ASTM B348) |
| Corrosion resistance | Excellent — the reference grade for this | Good, but lower than Gr2 |
| Formability | Excellent — bends and forms easily | Limited — work-hardens, needs more force |
| Machinability | Easier | Harder — more tool wear, slower cycle times |
| Weldability | Straightforward | Requires more controlled process |
| Relative cost | Lower | Higher — both material and processing |
| Governing ASTM standard | ASTM B348 (bar), B265 (sheet) | ASTM B348 (bar), B265 (sheet) |
| Aerospace-grade equivalent | — | AMS 4928 |
Already know which grade fits your part?
Skip the back-and-forth — tell us the spec and we'll match you with a verified Baoji supplier.
Which one your application actually needs
This matches the same logic our RFQ Builder uses to point buyers toward a starting spec:
- Chemical processing, marine and seawater equipment — corrosion resistance is the requirement, not strength. Gr2 is the standard choice. Specifying Gr5 here adds cost and machining difficulty for a strength margin the application doesn’t use.
- Structural parts, general machining, sporting goods (e.g. bike frames) — strength-to-weight ratio is the actual requirement. Gr5 is the standard choice.
- Aerospace components — Gr5, but typically to AMS 4928, not ASTM B348 — a stricter, separate specification. See our AMS titanium guide if you’re not sure which one your application needs.
- Medical implants — a purer version of Gr5 with tighter impurity limits, Gr23 (Ti-6Al-4V ELI), governed by ASTM F136 — not plain Gr5 and not Gr2.
The mistake worth avoiding
Gr5 is the grade most buyers have already heard of, so it gets treated as the “serious” or “premium” default even when the application is corrosion- driven, not strength-driven. Commercially pure titanium isn’t a downgrade from an alloy — it’s the correct engineering choice for a large share of industrial equipment, and it’s usually cheaper and faster to get quoted and machined. Before defaulting to Gr5, it’s worth asking what property the part actually depends on: if the honest answer is “it just needs to not corrode,” Gr2 is very likely the right spec.
Still not sure what fits you?
Tell us what it's for in the RFQ Builder and we'll help you figure out the spec before you contact a supplier.