AWS BNi-4 (N99640) Filler Metal
AWS BNi-4 is a nickel-based filler metal for brazing. Cited properties are appropriate for the as-fabricated (no temper or treatment) condition. BNi-4 is the AWS designation for this material. N99640 is the UNS number.
It has a fairly low tensile strength among nickel-based brazing fillers. In addition, it has a moderately high density and a moderately high embodied energy.
The graph bars on the material properties cards below compare AWS BNi-4 to: nickel-based brazing fillers (top), all nickel alloys (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
180 GPa 26 x 106 psi
Poisson's Ratio
0.31
Shear Modulus
67 GPa 9.8 x 106 psi
Tensile Strength: Ultimate (UTS)
430 MPa 62 x 103 psi
Thermal Properties
Brazing Temperature
1010 to 1180 °C 1850 to 2150 °F
Latent Heat of Fusion
340 J/g
Melting Completion (Liquidus)
1070 °C 1950 °F
Melting Onset (Solidus)
980 °C 1800 °F
Specific Heat Capacity
470 J/kg-K 0.11 BTU/lb-°F
Thermal Expansion
11 µm/m-K
Otherwise Unclassified Properties
Base Metal Price
60 % relative
Density
8.5 g/cm3 530 lb/ft3
Embodied Carbon
10 kg CO2/kg material
Embodied Energy
140 MJ/kg 60 x 103 BTU/lb
Embodied Water
220 L/kg 26 gal/lb
Common Calculations
Stiffness to Weight: Axial
12 points
Stiffness to Weight: Bending
22 points
Strength to Weight: Axial
14 points
Strength to Weight: Bending
15 points
Thermal Shock Resistance
16 points
Alloy Composition
Ni | 91.4 to 95.5 | |
Si | 3.0 to 4.0 | |
B | 1.5 to 2.2 | |
Fe | 0 to 1.5 | |
Co | 0 to 0.1 | |
C | 0 to 0.060 | |
Al | 0 to 0.050 | |
Ti | 0 to 0.050 | |
Zr | 0 to 0.050 | |
P | 0 to 0.020 | |
S | 0 to 0.020 | |
Se | 0 to 0.0050 | |
res. | 0 to 0.5 |
All values are % weight. Ranges represent what is permitted under applicable standards.
Followup Questions
Similar Alloys
Further Reading
AWS A5.8: Specification for Filler Metals for Brazing and Braze Welding