AWS BAg-4 (P07400) Filler Metal
AWS BAg-4 is a silver-based filler metal for brazing. Cited properties are appropriate for the as-fabricated (no temper or treatment) condition. BAg-4 is the AWS designation for this material. P07400 is the UNS number.
It has a fairly high heat capacity among silver-based braze fillers. In addition, it has a moderately low tensile strength and a moderately low density.
The graph bars on the material properties cards below compare AWS BAg-4 to: silver-based braze fillers (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
91 GPa 13 x 106 psi
Poisson's Ratio
0.33
Shear Modulus
34 GPa 5.0 x 106 psi
Tensile Strength: Ultimate (UTS)
150 MPa 22 x 103 psi
Thermal Properties
Brazing Temperature
740 to 900 °C 1370 to 1650 °F
Latent Heat of Fusion
140 J/g
Melting Completion (Liquidus)
780 °C 1430 °F
Melting Onset (Solidus)
670 °C 1240 °F
Specific Heat Capacity
330 J/kg-K 0.078 BTU/lb-°F
Thermal Expansion
21 µm/m-K
Otherwise Unclassified Properties
Density
8.9 g/cm3 550 lb/ft3
Embodied Carbon
40 kg CO2/kg material
Embodied Energy
630 MJ/kg 270 x 103 BTU/lb
Common Calculations
Stiffness to Weight: Axial
5.7 points
Stiffness to Weight: Bending
17 points
Strength to Weight: Axial
4.7 points
Strength to Weight: Bending
7.1 points
Thermal Shock Resistance
5.7 points
Alloy Composition
| Ag | 39 to 41 | |
| Cu | 29 to 31 | |
| Zn | 26 to 30 | |
| Ni | 1.5 to 2.5 | |
| res. | 0 to 0.15 |
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