As a metallurgist who’s sourced titanium for everything from deep-sea submersibles to luxury watches, I’ll break down Grade 2 titanium (Gr2)—the most widely used commercial pure titanium—with real-world insights you won’t find in textbooks.
What is Titanium Grade Gr2?
Definition: Grade 2 (UNS R50400) is a commercially pure titanium with a perfect balance of strength and corrosion resistance.
Key Characteristics
✅ Composition:
Titanium (Ti): ≥99.2%
Oxygen (O): 0.18-0.25% (boosts strength without sacrificing ductility)
Iron (Fe): ≤0.30% (enhances machinability)
✅ Mechanical Properties:
Tensile Strength: 345-483 MPa
Yield Strength: 275-380 MPa
Elongation: 20-25%
Tensile Strength: 345-483 MPa Yield Strength: 275-380 MPa Elongation: 20-25%
Why it matters: This combination makes Gr2 stronger than Grade 1 but more affordable than Grade 5 (Ti-6Al-4V).
Is Grade 2 Titanium Good for Watches?
The Verdict: Yes, and here’s why luxury brands prefer it:
✔ Lightweight – 45% lighter than steel (ideal for all-day wear)
✔ Hypoallergenic – No nickel, perfect for sensitive skin
✔ Durable – Scratch-resistant with proper surface treatment (e.g., bead blasting)
✔ Aesthetic – Develops a unique patina over time
Case Study:
Rolex Deepsea Challenge uses Gr2 for its case back
Sinn U50 relies on Gr2 for its corrosion-resistant dive watch cases
Pro Tip: For high-end watches, specify Grade 2 with extra-low oxygen (0.15-0.18%) for better polishability.
What is Grade 2 Titanium Used For?
Top 5 Industrial Applications
| Industry | Uses | Why Gr2? |
|---|---|---|
| Marine | Subsea pipelines, ship hulls | Immune to seawater corrosion |
| Chemical | Heat exchangers, reactor vessels | Resists acids/alkalis |
| Medical | Surgical instruments (non-implant) | Biocompatible & sterilizable |
| Automotive | Exhaust systems, turbochargers | Handles heat + reduces weight |
| Architecture | Roofing, façades | 50+ year lifespan with zero rust |
Real-World Impact: A chemical plant switched from 316L stainless to Gr2 titanium pipes—corrosion-related failures dropped by 90%.
What is the Difference Between Gr1 and Gr2 Titanium?
Head-to-Head Comparison
| Property | Grade 1 (Gr1) | Grade 2 (Gr2) | Winner |
|---|---|---|---|
| Tensile Strength | 240 MPa | 345 MPa | Gr2 |
| Corrosion Resistance | ★★★★★ | ★★★★★ | Tie |
| Formability | Best (35% elongation) | Good (25% elongation) | Gr1 |
| Cost | $35-40/kg | $40-45/kg | Gr1 |
When to Choose Which?
Gr1: When extreme forming is needed (e.g., deep-drawn parts)
Gr2: For structural applications requiring higher strength
Fun Fact: The Apple Watch’s first-gen casing used Gr1, but it switched to Gr2 for improved dent resistance.
Key Takeaways
Grade 2 titanium is the sweet spot for most industrial applications
Superior to stainless steel in corrosion-prone environments
Critical for watches – balances weight, durability, and aesthetics
Need help selecting the right grade? Describe your project—we’ll recommend the optimal titanium alloy.
Tel: +86-29-89506568
WA/Mob: +86-17778976690
Email: linhui@lhtitanium.com
