UNS R04295 Niobium-Hafnium Alloy
R04295 alloy is a niobium alloy. Cited properties are appropriate for the annealed condition. It has a moderately low density among the alloys in the same category in the database. The graph bars on the material properties cards below compare R04295 alloy to: niobium alloys (top), all alloys in the same category (middle), and the entire database (bottom). A full bar means this is the highest value in the relevant set. A half-full bar means it's 50% of the highest, and so on.
Mechanical Properties
Elastic (Young's, Tensile) Modulus
100 GPa 15 x 106 psi
Elongation at Break
22 %
Poisson's Ratio
0.38
Shear Modulus
37 GPa 5.4 x 106 psi
Tensile Strength: Ultimate (UTS)
410 MPa 60 x 103 psi
Tensile Strength: Yield (Proof)
300 MPa 43 x 103 psi
Thermal Properties
Latent Heat of Fusion
300 J/g
Specific Heat Capacity
260 J/kg-K 0.062 BTU/lb-°F
Thermal Expansion
7.2 µm/m-K
Otherwise Unclassified Properties
Density
9.0 g/cm3 560 lb/ft3
Embodied Water
950 L/kg 110 gal/lb
Common Calculations
Resilience: Ultimate (Unit Rupture Work)
84 MJ/m3
Resilience: Unit (Modulus of Resilience)
430 kJ/m3
Stiffness to Weight: Axial
6.3 points
Stiffness to Weight: Bending
17 points
Strength to Weight: Axial
13 points
Strength to Weight: Bending
14 points
Thermal Shock Resistance
40 points
Alloy Composition
| Nb | 85.9 to 90.3 | |
| Hf | 9.0 to 11 | |
| Ti | 0.7 to 1.3 | |
| Zr | 0 to 0.7 | |
| W | 0 to 0.5 | |
| Ta | 0 to 0.5 | |
| O | 0 to 0.025 | |
| C | 0 to 0.015 | |
| N | 0 to 0.010 | |
| H | 0 to 0.0015 |
All values are % weight. Ranges represent what is permitted under applicable standards.
Followup Questions
Similar Alloys
Further Reading
ASTM B654: Standard Specification for Niobium-Hafnium Alloy Foil, Sheet, Strip, and Plate
ASTM B655: Standard Specification for Niobium-Hafnium Alloy Bar, Rod, and Wire
Extractive Metallurgy of Niobium, C. K. Gupta and A. K. Suri, 1993
Sintering of Advanced Materials: Fundamentals and Processes, Zhigang Zak Fang (editor), 2010