Nickel Alloy BNi-7 AS_BRAZED
Heat-treated state
UNS N99710 · ISO B-Ni7
AS_BRAZED = as-Brazed joint
Refer to these vacuum-brazed joint values for 304/316 stainless with a 0.03-0.08 mm gap when checking structural design, not as properties of the filler metal itself.
Values for the AS_BRAZED condition
What is BNi-7 AS_BRAZED?
BNi-7 AS_BRAZED is BNi-7 heat treated to AS_BRAZED — refer to these vacuum-brazed joint values for 304/316 stainless with a 0.03-0.08 mm gap when checking structural design, not as properties of the filler metal itself. BNi-7 AS_BRAZED has a tensile strength of 500 MPa (72.5 ksi), weaker than 85% of nickel alloy grades. Elongation at break is 2% and the elastic modulus is 175 GPa (25.4 Msi). BNi-7 AS_BRAZED has a density of 7.6 g/cm³ (0.275 lb/in³), lighter than 99% of nickel alloy grades. It melts at 890°C (1,634 °F).
Limitations
- Difficult to machine — 8/100, worse than 96% of nickel alloy grades
- Limited ductility — 2%, worse than 95% of nickel alloy grades
- Hard to polish — 55/100, worse than 95% of nickel alloy grades
- Difficult to weld — 10/100, worse than 94% of nickel alloy grades
- Low stiffness — 175 GPa (25.4 Msi), worse than 90% of nickel alloy grades
BNi-7 AS_BRAZED properties
Typical room-temperature values for BNi-7 AS_BRAZED; 6 are specific to this condition. Other listed values are BNi-7 reference data and may not represent this condition. Bars are the position among nickel alloy grades.
Physical3
BNi-7 AS_BRAZED has a density of 7.6 g/cm³ (0.275 lb/in³), lighter than 99% of nickel alloy grades. It melts at 890°C (1,634 °F).
Mechanical8
BNi-7 AS_BRAZED has a tensile strength of 500 MPa (72.5 ksi), weaker than 85% of nickel alloy grades. Elongation at break is 2% and the elastic modulus is 175 GPa (25.4 Msi).
Thermal5
BNi-7 AS_BRAZED is rated for continuous service to 700°C (1,292 °F). It conducts heat at 12 W/m·K (6.93 BTU/hr·ft·°F), better than 65% of nickel alloy grades. Thermal expansion is 13 µm/m·K (7.22 µin/in·°F).
Electrical2
BNi-7 AS_BRAZED has an electrical resistivity of 1.2×10⁻⁶ Ω·m.
Chemical & Environmental2
Corrosion resistance is good (60/100), worse than 89% of nickel alloy grades.
Sustainability4
Producing a kilogram of BNi-7 AS_BRAZED takes about 135 MJ of energy and emits 13 kg of CO₂ — less than 84% of nickel alloy grades. Typical recycled content is 10%.
Manufacturability4
BNi-7 AS_BRAZED's machinability is not recommended (8/100, worse than 96% of nickel alloy grades); weldability not recommended (10/100).
Values are nominal handbook figures for design screening. Confirm any required mill or lot documentation when quoting.
Working with BNi-7 AS_BRAZED
Is BNi-7 easy to machine?
The solidified filler contains hard, brittle phosphides and is effectively unmachinable; grind excess braze off with diamond or aluminium oxide wheels. Avoid turning or milling across the fillet.
Can BNi-7 be welded?
Not usable as a fusion welding filler. Re-melting the braze seam or arc contact produces phosphorus segregation cracks, so repair by re-brazing.
Can BNi-7 be formed, bent or molded?
Supplied as powder, paste, amorphous foil or preform; the amorphous foil can be sheared and blanked into shapes. Hold joint clearance at 0.025-0.075 mm for best capillary fill.
What surface finishes work on BNi-7?
Joints are ready for service after brazing at 950-1065 C in a vacuum or dry hydrogen furnace. Seams can be plated or passivated, but extended high-temperature holds increase phosphorus diffusion into the parent metal and form a brittle layer.
BNi-7 chemical composition (wt %)
Limits by weight percent from the governing specification, written the way the spec states them — a single maximum for impurities, a range for alloying elements, and the base element as balance. Nominal is the typical mid-range value.
| Element | Spec limit (wt %) | Nominal |
|---|---|---|
| Cr | 13 – 15 | 14 |
| Pself-fluxing element, forms low-melting eutectic | 9.7 – 10.5 | 10.1 |
| C | ≤ 0.06 | |
| Si | ≤ 0.1 | |
| Blow boron, avoids diffusion attack in nuclear/thin-wall parts | ≤ 0.01 | |
| Fe | ≤ 0.2 | |
| S | ≤ 0.02 | |
| Co | ≤ 0.1 | |
| Al | ≤ 0.05 | |
| Ti | ≤ 0.05 | |
| Zr | ≤ 0.05 | |
| Se | ≤ 0.01 | |
| Others (total) | ≤ 0.5 | |
| Ni | balance |
BNi-7 AS_BRAZED — frequently asked
What is BNi-7 AS_BRAZED used for?
BNi-7 AS_BRAZED is typically used for stainless steel brazing, corrosion-resistant instrument fittings and low-temperature furnace brazing. In short: chromium-bearing self-fluxing braze; better corrosion than BNi-6; amorphous foil available.
What is the tensile strength of BNi-7 AS_BRAZED?
BNi-7 AS_BRAZED has a typical tensile strength of 500 MPa (72.5 ksi) — weaker than 85% of nickel alloy grades.
Is BNi-7 AS_BRAZED easy to machine?
Not especially — machinability is rated not recommended (8/100, worse than 96% of nickel alloy grades). The solidified filler contains hard, brittle phosphides and is effectively unmachinable; grind excess braze off with diamond or aluminium oxide wheels. Avoid turning or milling across the fillet.
Can BNi-7 AS_BRAZED be welded?
Not readily — weldability is rated not recommended (10/100). Not usable as a fusion welding filler. Re-melting the braze seam or arc contact produces phosphorus segregation cracks, so repair by re-brazing.
What surface finishes work on BNi-7 AS_BRAZED?
Joints are ready for service after brazing at 950-1065 C in a vacuum or dry hydrogen furnace. Seams can be plated or passivated, but extended high-temperature holds increase phosphorus diffusion into the parent metal and form a brittle layer.
Can BNi-7 AS_BRAZED be formed, bent or molded?
Supplied as powder, paste, amorphous foil or preform; the amorphous foil can be sheared and blanked into shapes. Hold joint clearance at 0.025-0.075 mm for best capillary fill.
What is the maximum service temperature of BNi-7 AS_BRAZED?
BNi-7 AS_BRAZED is rated for continuous use to about 700°C (1,292 °F). Strength falls off well before that limit — check the elevated-temperature data for load-bearing parts.
Sources
- AWS A5.8/A5.8M — Specification for Filler Metals for Brazing and Braze Welding — American Welding Society (2019)
- GB/T 10859 (2008)
- ASM Handbook Vol.6 — Welding, Brazing and Soldering (Brazing Filler Metals) — ASM International (1993)
- Nickel braze filler metal powder & amorphous foil datasheets (BNi-7 / N99710) — Wall Colmonoy / Lucas-Milhaupt / Metglas (2023)
Property data is compiled from published supplier and standards handbooks and normalised for comparison. Nothing on this page is a certification — request mill certs, CoC or material test reports with your order.