Titanium Beta 21S UNS R58210
Titanium Beta 21 S (Timetal 21S) is one of the beta titanium alloys which was developed as an oxidation-resistant aerospace material and as a matrix for metal-matrix composites.
Titanium Beta 21S Strip, Coil, Foil, Wire
What is Titanium Beta 21S?
Titanium Beta 21 S (Timetal 21S) is one of the beta titanium alloys which was developed as an oxidation-resistant aerospace material and as a matrix for metal-matrix composites. Titanium Beta 21 S (Grade 21) offers the good formability and weldability of a beta alloy, but with greatly improved oxidation resistance and creep strength. The composition of Beta 21S is Ti-15Mo-2.7Nb-3Al-0.2Si, designed to improve corrosion resistance with molybdenum and niobium working together to raise corrosion resistance to very high levels. Beta-titanium alloys show a reduced Young’s modulus compared to pure titanium or Ti-6Al-4V, and can be composed completely from biocompatible elements making it a great choice for some medical applications.
Beta Titanium has strength & modulus of elasticity ratios almost twice those of austenitic stainless steel, larger elastic deflections in springs, and reduced force per unit displacement 2.2 times below those of stainless steel appliances.
Grade 21 Titanium has one of the lowest hydrogen uptake efficiency levels of any titanium alloy. It combines high strength, high corrosion resistance, and fracture toughness making it an ideal candidate for orthopedic implants, deep sour oil wells, geothermal brine wells, aerospace honeycomb, aerospace fasteners, and aerospace engine applications.
Specifications
| Standard |
|---|
ASTM Grade 21 |
ASTM B265 |
Common Applications for Titanium Grade 21
- High resistance to aircraft hydraulic fluids
- Used in warm airframes or engine structures
- Structural Honeycombs
- Fasteners
- metal matrix composites
- welded and seamless tubing
Chemical Composition of Titanium Beta 21S
| Element | Min | Max |
|---|---|---|
| Titanium | Balance | Balance |
| Molybdenum | 14.0 | 16.0 |
| Niobium | 2.4 | 3.2 |
| Aluminum | 2.5 | 3.5 |
| Silicon | 0.15 | 0.25 |
| Iron | 0.40 | 0.40 |
| Oxygen | 0.11 | 0.17 |
| Carbon | 0.05 | 0.05 |
| Nitrogen | 0.05 | 0.05 |
| Hydrogen | 0.015 | 0.015 |
| Residuals (each) | 0.10 | 0.10 |
| Residuals (total) | 0.40 | 0.40 |
Common Titanium Grade Names
| Name | Code | Description 1 | Description 2 | ASTM | AMS | UNS |
| Titanium 21S | TI21S | Metastable beta alloy | Timetal 21S | R58210 |
Physical Properties of Titanium 21S
Density: 0.178 lbs/in3, 4.94 g/cm3
Mean Coefficient of Thermal Expansion: in/in/° F (mm/m/° C):
70 - 212 °F (20 - 100 ° C) 3.93 x 10-5 (7.07)
Thermal Conductivity: BTU-in/h-ft-° F (W/m-° K):
70 ° F (21 ° C): 52.7 (7.6)
Modulus of Elasticity: ksi (MPa)
10.5 - 12 x 103 (72 - 85 x 103) in tension
Melting Point: 3034 °F (1668 °C)
Available Metal Product Forms
Coil
- Titanium Beta 21S Strip
- Titanium Beta 21S Foil
- Titanium Beta 21S Ribbon
Wire
Mechanical Properties of Titanium Beta 21S at Room Temperature
Properties: Annealed Condition
(1550 °F)
Ultimate Tensile Strength: 155 KSI min (1068 MPa min)
Yield Strength (0.2% offset): 110 KSI min (758 MPa min)
Elongation: 12%
Aged Properties: Typical
Aging Temp/Time: 1000 °F / 8 HOURS
Ultimate Tensile Strength: 170 KSI min (1172 MPa min)
Yield Strength (0.2% offset): 160 KSI min (1103 MPa min)
Elongation: 4%
Aging Temp/Time: 1100 °F / 8 HOURS
Ultimate Tensile Strength: 150 KSI min (1034 MPa min )
Yield Strength (0.2% offset): 140 KSI min (965 MPa min)
Elongation: 6%
Aging Temp/Time: 1275 °F / 8 HOURS
Ultimate Tensile Strength: 125 KSI min (862 MPa min)
Yield Strength (0.2% offset): 115 KSI min (793 MPa min)
Elongation: 10%
Additional Properties
Titanium Beta 21S Corrosion Resistance
Refer to NACE (National Associate of Corrosion Engineers) for recommendations.
Finishes for Ti Beta 21S
| #1 | Hot rolled annealed and descaled. It is available in strip, foil and ribbon. It is used for applications where a smooth decorative finish is not required. |
| #2D | Dull finish produced by cold rolling, annealing and descaling. Used for deep drawn parts and those parts that need to retain lubricants in the forming process. |
| #2B | Smooth finish produced by cold rolling, annealing and descaling. A light cold rolling pass is added after anneal with polished rolls giving it a brighter finish than 2D. |
| #BA | Bright annealed cold rolled and bright annealed |
| #CBA | Course bright annealed cold rolled matte finish and bright anneal |
| #2 | Cold Rolled |
| #2BA | Smooth finish produced by cold rolling and bright annealing. A light pass using highly polished rolls produces a glossy finish. A 2BA finish may be used for lightly formed applications where a glossy finish is desired in the formed part. |
| Polished | Various grit finish for specific polish finished requirements. |
* Not all finishes are available for all alloys - Contact Ulbrich Sales for more information.
Wire Finishes
Inquire with Ulbrich Wire for wire finishes.
Grade 21 Titanium Heat Treatment
Titanium Alloy Beta 21 S (Grade 21) can be hardened by aging.
Welding
For best results refer to: SSINA's "Welding of Stainless Steels and Other Joining Methods".
Limitation of Liability and Disclaimer of Warranty: In no event will Ulbrich Stainless Steels & Special Metals, Inc., be liable for any damages arising from the use of the information included in this document or that it is suitable for the 'applications' noted. We believe the information and data provided to be accurate to the best of our knowledge but, all data is considered typical values only. It is intended for reference and general information and not recommended for specification, design or engineering purposes. Ulbrich assumes no implied or express warranty in regard to the creation or accuracy of the data provided in this document.