Nickel Alloy BNi-5
UNS N99650, N99610 · ASTM A5.8 BNi-5 · ISO B-Ni5
BNi-5 is a high-chromium, iron-free Ni-Cr-Si-B brazing filler metal (UNS N99650 and N99610, AWS A5.8 BNi-5).
Reference datasheet — BNi-5 is not in the instant-quote catalog. Upload your part and an engineer will quote it in this grade or suggest the closest stocked equivalent.
BNi-5 tempers and conditions
BNi-5 is supplied in one standard condition, AS-BRAZED.
Supply forms, finishes and certifications
Ways BNi-5 is supplied — form, process route, surface or paperwork — without a datasheet of their own. The property values above apply.
| Option | What it is | Type |
|---|---|---|
PREFORM | Sintered preform | Supply form |
PASTE | Powder pre-mixed with organic binder/vehicle | Printing process |
POWDERDefault | Gas-atomised braze powder | Printing process |
TAPE | Transfer tape / flexible sheet | Printing process |
What is BNi-5?
BNi-5 is a high-chromium, iron-free Ni-Cr-Si-B brazing filler metal (UNS N99650 and N99610, AWS A5.8 BNi-5). Engineers choose it when the joint itself must resist oxidation and corrosion at temperature: melting point 1080 C, maximum service temperature 980 C and deposit density 7.8 g/cm3, supplied as powder, paste, tape and sintered preform. The as-brazed deposit is hard and brittle at about 450 HV, so fillets are ground rather than machined, and brazing requires 1150-1205 C furnace capability. Where a lower brazing temperature is acceptable, the phosphorus-bearing BNi-7 is the nearest alternative. BNi-5 has a density of 7.8 g/cm³ (0.282 lb/in³), lighter than 96% of nickel alloy grades. It melts at 1,080°C (1,976 °F). BNi-5 has a tensile strength of 620 MPa (89.9 ksi), weaker than 68% of nickel alloy grades. Elongation at break is 2% and the elastic modulus is 195 GPa (28.3 Msi).
What is BNi-5 used for?
- gas turbine component brazing
- high-temperature exhaust assemblies
- corrosion-resistant joints
Limitations
- Limited ductility — 2%, worse than 95% of nickel alloy grades
- Difficult to machine — 10/100, worse than 93% of nickel alloy grades
- Difficult to weld — 15/100, worse than 87% of nickel alloy grades
- Hard to polish — 60/100, worse than 84% of nickel alloy grades
BNi-5 properties
Typical room-temperature values; bars are the position among nickel alloy grades.
Physical3
BNi-5 has a density of 7.8 g/cm³ (0.282 lb/in³), lighter than 96% of nickel alloy grades. It melts at 1,080°C (1,976 °F).
Mechanical8
BNi-5 has a tensile strength of 620 MPa (89.9 ksi), weaker than 68% of nickel alloy grades. Elongation at break is 2% and the elastic modulus is 195 GPa (28.3 Msi).
Thermal5
BNi-5 is rated for continuous service to 980°C (1,796 °F). It conducts heat at 13 W/m·K (7.51 BTU/hr·ft·°F), better than 71% of nickel alloy grades. Thermal expansion is 13.5 µm/m·K (7.5 µin/in·°F).
Electrical2
BNi-5 has an electrical resistivity of 1.2×10⁻⁶ Ω·m.
Chemical & Environmental2
Corrosion resistance is very good (72/100), worse than 71% of nickel alloy grades.
Sustainability4
Producing a kilogram of BNi-5 takes about 165 MJ of energy and emits 13 kg of CO₂ — more than 54% of nickel alloy grades. Typical recycled content is 15%.
Manufacturability5
BNi-5's machinability is not recommended (10/100, worse than 93% of nickel alloy grades); weldability poor (15/100).
Common Calculations4
Values are nominal handbook figures for design screening. Certified mill or lot data ships with every FabDigit order on request.
Strength versus weight in the nickel alloy family
Yield strength against density for every nickel alloy grade FabDigit runs. BNi-5 is highlighted; hover a dot for its name, or open the interactive family chart.
Working with BNi-5
Is BNi-5 easy to machine?
The solidified deposit is hard and brittle (≈450 HV) — remove excess fillet by grinding or abrasive blasting rather than turning/milling.
Can BNi-5 be welded?
Not a fusion welding consumable; do not re-melt joints locally, and avoid subsequent weld heat above ~1000 °C near brazed seams.
Can BNi-5 be formed, bent or molded?
Supplied as powder, paste, tape or sintered preform; braze in vacuum (10⁻⁴ torr) or dry hydrogen at 1150–1205 °C with 0.025–0.075 mm joint clearance and slow binder burn-out below 500 °C.
BNi-5 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 | 18.5 – 19.5 | 19 |
| Si | 9.75 – 10.5 | 10.1 |
| Bessentially boron-free — avoids boron diffusion/erosion of thin sections | ≤ 0.03 | 0.01 |
| C | ≤ 0.06 | 0.03 |
| Feresidual; some purchase specs restrict further | ≤ 0.5 | 0.2 |
| P | ≤ 0.02 | |
| S | ≤ 0.02 | |
| Al | ≤ 0.05 | |
| Ti | ≤ 0.05 | |
| Zr | ≤ 0.05 | |
| Other (total) | ≤ 0.5 | |
| Ni | balance |
What surface finishes work on BNi-5?
Joints can be passivated, aluminide/ diffusion coated or grit-blasted; the high-Cr deposit forms a protective Cr₂O₃ scale and needs no plating for oxidation service.
Surface treatments FabDigit runs on nickel alloy parts — pick them in the quote configurator or call them out on the drawing. Each links to its datasheet in the surface-finish library (thickness, specs, call-out, material verdicts).
Plating
Thermal Spray
Equivalent designations
Standards and trade names that resolve to Nickel Alloy BNi-5 in FabDigit's catalog. Equivalence is nominal — check the exact specification when certification matters.
- UNS
- N99650N99610
- ASTM
- A5.8 BNi-5
- ISO
- B-Ni5
How much does BNi-5 cost?
BNi-5 is a high-cost nickel alloy ($$$$), pricier than about 78% of the materials FabDigit quotes. Part price depends far more on geometry, tolerance and quantity than on the raw stock — upload a CAD file for a live quote.
BNi-5 — frequently asked
What is BNi-5 used for?
BNi-5 is typically used for gas turbine component brazing, high-temperature exhaust assemblies and corrosion-resistant joints. In short: highest-chromium nickel braze; 980 C service capability; no boride-free ductility gain.
What is the tensile strength of BNi-5?
BNi-5 has a typical tensile strength of 620 MPa (89.9 ksi) — weaker than 68% of nickel alloy grades.
Is BNi-5 easy to machine?
Not especially — machinability is rated not recommended (10/100, worse than 93% of nickel alloy grades). The solidified deposit is hard and brittle (≈450 HV) — remove excess fillet by grinding or abrasive blasting rather than turning/milling.
Can BNi-5 be welded?
Not readily — weldability is rated poor (15/100). Not a fusion welding consumable; do not re-melt joints locally, and avoid subsequent weld heat above ~1000 °C near brazed seams.
What surface finishes work on BNi-5?
Joints can be passivated, aluminide/ diffusion coated or grit-blasted; the high-Cr deposit forms a protective Cr₂O₃ scale and needs no plating for oxidation service.
Can BNi-5 be formed, bent or molded?
Supplied as powder, paste, tape or sintered preform; braze in vacuum (10⁻⁴ torr) or dry hydrogen at 1150–1205 °C with 0.025–0.075 mm joint clearance and slow binder burn-out below 500 °C.
What is the maximum service temperature of BNi-5?
BNi-5 is rated for continuous use to about 980°C (1,796 °F). Strength falls off well before that limit — check the elevated-temperature data for load-bearing parts.
How much does BNi-5 cost?
BNi-5 is a high-cost nickel alloy ($$$$), pricier than about 78% of the materials FabDigit quotes. Part price depends far more on geometry, tolerance and quantity than on the raw stock — upload a CAD file for a live quote.
Sources
- AWS A5.8M/A5.8 Specification for Filler Metals for Brazing and Braze Welding — American Welding Society (2019)
- AMS 4782 Nickel Alloy Brazing Filler Metal, 19Cr 10Si — SAE International (2018)
- ASM Handbook Vol. 6 — Welding, Brazing and Soldering (Brazing Filler Metals) — ASM International (1993)
- AWS Brazing Handbook, 5th ed. — American Welding Society (2007)
- Nickel braze filler metal product data (powder/paste/tape forms) — Braze filler metal producers (e.g. Höganäs, Lucas-Milhaupt, Wall Colmonoy) (2023)
- GB/T 6418 (2008)
Property data is compiled from published supplier and standards handbooks and normalised for comparison; hardness values on non-Brinell scales are converted approximately for charting only. Manufacturability limits are FabDigit quote-engine defaults and may be relaxed by engineering review. Nothing on this page is a certification — request mill certs, CoC or material test reports with your order.