Equivalent Grades of Grade 2 Titanium
Dec 10, 2025
What Is GR2 Titanium
Titanium Grade 2 (GR2, UNS R50400, W.Nr. 3.7035) is used for welding commercially pure titanium, where low weight, high corrosion resistance, and good mechanical strength are essential. This filler material is particularly suitable for marine environments, chemical process industries, and medical engineering structures. The weld metal deposited with Titanium GR2 has excellent resistance to seawater, chlorides, acids, and other corrosive media, while maintaining high toughness and formability. The material is biocompatible, making it suitable for welding medical implants and equipment.
International Equivalents
Designated as UNS R50400, ASTM Grade 2 titanium has several international equivalents: DIN 3.7035 (German), BS 25-35 t/in2 (British), JIS Class 2 (Japanese), and Gr. TA2 (Chinese GB).
Chemical Composition Comparison (Percent, Max)
| Grade | C | H | O | N | Fe |
|---|---|---|---|---|---|
| ASTM Gr.2 | 0.10 | 0.010 | 0.25 | 0.03 | 0.30 |
| DIN 3.7035 | 0.08 | 0.013 | 0.20 | 0.06 | 0.25 |
| GOST BTI-0 | 0.07 | 0.010 | 0.20 | 0.04 | 0.30 |
| JIS Class 2 | - | 0.015 | 0.20 | 0.05 | 0.25 |
| GB TA2 | 0.10 | 0.015 | 0.25 | 0.05 | 0.30 |
Mechanical Properties Comparison
| Grade | Tensile strength (MPa) | Yield strength (MPa) | Elongation (%) |
|---|---|---|---|
| ASTM Gr.2 | 343 min | 275-410 | 20 |
| DIN 3.7035 | 372 min | 245 min | 22 |
| GOST BTI-0 | 390-540 | - | 20 |
| JIS Class 2 | 343-510 | 215 min | 23 |
| GB TA2 | 441 min | 373 min | 20 |
Gr2 vs Gr5
Gr2 is a commercially pure titanium with tensile strength about 344 MPa, offering excellent corrosion resistance and easy fabrication. Gr5 (Ti-6Al-4V) contains 6 percent aluminum and 4 percent vanadium, increasing strength to about 1000 MPa and fatigue resistance, making it ideal for aerospace, automotive, and medical applications, but more expensive and harder to machine.
Frequently Asked Questions
What is the equivalent of Grade 2 titanium? DIN 3.7035 (German), BS 25-35 t/in2 (British), JIS Class 2 (Japanese), and GB TA2 (Chinese).
What is the UNS number? R50400.
Is Gr2 stronger than Gr1? Yes, Gr2 has higher strength and hardness with slightly lower ductility.
Why is Grade 2 commonly used as a filler for welding commercially pure titanium? The weld metal deposited with Grade 2 matches the corrosion resistance and mechanical strength of commercially pure titanium base materials, giving joints good resistance to seawater, chlorides and acids while retaining high toughness and formability.
Do the international equivalents have identical chemical limits? No. Each national standard sets slightly different maximums for carbon, hydrogen, oxygen, nitrogen and iron, as shown in the comparison table. The designations are considered equivalent for most procurement and fabrication purposes, but the specific limits should be checked against the requirement before substitution.
When should Grade 5 be chosen instead of Grade 2? Grade 5 (Ti-6Al-4V) is selected when much higher strength and fatigue resistance are required, such as in aerospace, automotive and load-bearing medical parts. Grade 2 remains the economical choice for corrosion-dominated service because it is easier to form, weld and machine.
