Nickel Alloy BNi-9
UNS N99612 · ISO B-Ni9
BNi-9 (UNS N99612) is a high-chromium Ni-Cr-B brazing filler from the AWS BNi family, developed for repair brazing of nickel and cobalt superalloys.
Reference datasheet — BNi-9 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-9 tempers and conditions
BNi-9 is supplied in 3 conditions, soft to hard.
Compare all 3 conditionsHide
| Condition · open for datasheet | Best for | Yield MPa | Tensile MPa | Elong. % | Hardness | Conductivity |
|---|---|---|---|---|---|---|
Sintered preform / ring (binder-free pressed and sintered powder) | Pick for high-purity vacuum brazing with no binder residue and exact filler volume per joint. | 55 | 0 | 42 HRC | 1.2 % IACS | |
solidified joint deposit (no diffusion cycle) | Baseline joint condition after 1065–1205 °C vacuum braze cycle; strong but boride-embrittled if gaps are wide. | 460 | 550 | 1 | 52 HRC | 1.4 % IACS |
Diffusion brazed / post-braze diffusion heat treated | Extended hold (e.g. 4–24 h at 1040–1200 °C) redistributes boron, dissolves centreline borides and raises joint ductility and creep life. | 520 | 700 | 4 | 39 HRC | 1.5 % IACS |
Supply forms, finishes and certifications
Ways BNi-9 is supplied — form, process route, surface or paperwork — without a datasheet of their own. The property values above apply.
| Option | What it is | Type |
|---|---|---|
PASTE | Powder in organic binder/gel for dispensing | Printing process |
POWDERDefault | Gas-atomized braze powder | Printing process |
TAPE | Transfer tape / flexible sheet preform | Printing process |
What is BNi-9?
BNi-9 (UNS N99612) is a high-chromium Ni-Cr-B brazing filler from the AWS BNi family, developed for repair brazing of nickel and cobalt superalloys. It melts at 1055 °C, is rated for service to 980 °C, and is supplied as powder, paste, tape or sintered preform rather than as wire or foil. Engineers select it for high-temperature corrosion and oxidation resistance in hot-section joints brazed in vacuum or dry hydrogen. The trade-off is a hard, boride-containing deposit that cannot be turned or milled and must not be fusion welded over; BNi-10 or BNi-11 are the nearest choices when wide-gap filling is required. BNi-9 has a density of 7.9 g/cm³ (0.285 lb/in³), lighter than 92% of nickel alloy grades. It melts at 1,055°C (1,931 °F). BNi-9 has a tensile strength of 550 MPa (79.8 ksi), weaker than 77% of nickel alloy grades. Elongation at break is 1% and the elastic modulus is 200 GPa (29 Msi).
What is BNi-9 used for?
- Superalloy turbine repair brazing
- Aerospace hot-section component joints
- Turbine vane and nozzle segment brazing
- Combustor hardware braze repair
- High-temperature corrosion-resistant furnace joints
- Overhaul of gas turbine static structures
Advantages
- Conducts heat well — 14 W/m·K (8.09 BTU/hr·ft·°F), better than 77% of nickel alloy grades
Limitations
- Limited ductility — 1%, worse than 98% of nickel alloy grades
- Hard to polish — 55/100, worse than 95% of nickel alloy grades
- Limited formability — 5/100, worse than 91% of nickel alloy grades
- Difficult to weld — 15/100, worse than 87% of nickel alloy grades
BNi-9 properties
Typical room-temperature values; bars are the position among nickel alloy grades.
Physical3
BNi-9 has a density of 7.9 g/cm³ (0.285 lb/in³), lighter than 92% of nickel alloy grades. It melts at 1,055°C (1,931 °F).
Mechanical6
BNi-9 has a tensile strength of 550 MPa (79.8 ksi), weaker than 77% of nickel alloy grades. Elongation at break is 1% and the elastic modulus is 200 GPa (29 Msi).
Thermal5
BNi-9 is rated for continuous service to 980°C (1,796 °F). It conducts heat at 14 W/m·K (8.09 BTU/hr·ft·°F), better than 77% of nickel alloy grades. Thermal expansion is 12.5 µm/m·K (6.94 µin/in·°F).
Electrical2
BNi-9 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.
Sustainability3
Producing a kilogram of BNi-9 takes about 165 MJ of energy and emits 13 kg of CO₂ — more than 54% of nickel alloy grades. Typical recycled content is 5%.
Manufacturability5
BNi-9's machinability is not recommended (12/100, worse than 86% of nickel alloy grades); weldability poor (15/100); formability not recommended (5/100).
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-9 is highlighted; hover a dot for its name, or open the interactive family chart.
Working with BNi-9
Is BNi-9 easy to machine?
Solidified deposit is hard and brittle — remove excess fillet by grinding or EDM rather than turning/milling.
Can BNi-9 be welded?
Not a fusion-welding filler; boron pickup in a fusion weld over a BNi-9 joint causes hot cracking, so machine out old braze before welding repairs.
Can BNi-9 be formed, bent or molded?
Supplied only as powder, paste, tape or sintered preform; braze at 1065–1205 °C in vacuum (≤10⁻³ mbar) or dry hydrogen with joint gaps 0.025–0.075 mm.
BNi-9 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 | 13.5 – 16.5 | 15 |
| Bmelting point depressant; diffuses rapidly into base metal | 3.25 – 4 | 3.6 |
| C | ≤ 0.06 | |
| Si | ≤ 0.1 | |
| Fe | ≤ 0.2 | |
| Al | ≤ 0.05 | |
| Ti | ≤ 0.05 | |
| Zr | ≤ 0.05 | |
| P | ≤ 0.02 | |
| S | ≤ 0.02 | |
| Others (total) | ≤ 0.5 | |
| Ni | balance |
What surface finishes work on BNi-9?
Grit-blast/clean and passivate the parent alloy; the high-Cr deposit forms a protective oxide in service and needs no plating, though aluminide/Pt-Al coatings can be applied over diffused joints.
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-9 in FabDigit's catalog. Equivalence is nominal — check the exact specification when certification matters.
- UNS
- N99612
- ISO
- B-Ni9
How much does BNi-9 cost?
BNi-9 is a high-cost nickel alloy ($$$$), pricier than about 78% of the materials FabDigit quotes. Part price depends far more on geometry, tolerance and quantity than on the raw stock — upload a CAD file for a live quote.
BNi-9 — frequently asked
What is BNi-9 used for?
BNi-9 is typically used for superalloy turbine repair brazing, aerospace hot-section component joints, turbine vane and nozzle segment brazing, combustor hardware braze repair, high-temperature corrosion-resistant furnace joints and overhaul of gas turbine static structures. In short: high-chromium superalloy braze filler; service to 980 °C; vacuum or hydrogen brazing only.
What is the tensile strength of BNi-9?
BNi-9 has a typical tensile strength of 550 MPa (79.8 ksi) — weaker than 77% of nickel alloy grades. Strength varies by condition: see the 3 listed tempers.
Is BNi-9 easy to machine?
Not especially — machinability is rated not recommended (12/100, worse than 86% of nickel alloy grades). Solidified deposit is hard and brittle — remove excess fillet by grinding or EDM rather than turning/milling.
Can BNi-9 be welded?
Not readily — weldability is rated poor (15/100). Not a fusion-welding filler; boron pickup in a fusion weld over a BNi-9 joint causes hot cracking, so machine out old braze before welding repairs.
What surface finishes work on BNi-9?
Grit-blast/clean and passivate the parent alloy; the high-Cr deposit forms a protective oxide in service and needs no plating, though aluminide/Pt-Al coatings can be applied over diffused joints.
Can BNi-9 be formed, bent or molded?
Supplied only as powder, paste, tape or sintered preform; braze at 1065–1205 °C in vacuum (≤10⁻³ mbar) or dry hydrogen with joint gaps 0.025–0.075 mm.
What is the maximum service temperature of BNi-9?
BNi-9 is rated for continuous use to about 980°C (1,796 °F). Strength falls off well before that limit — check the elevated-temperature data for load-bearing parts.
How much does BNi-9 cost?
BNi-9 is a high-cost nickel alloy ($$$$), 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 — AWS (2019)
- ASTM/SAE Unified Numbering System (UNS N99612) — SAE/ASTM (2017)
- ASM Handbook Vol. 6 — Welding, Brazing and Soldering (nickel-base brazing filler metals) — ASM International (1993)
- Nickel-base braze filler metal datasheets (powder/paste/tape/preform forms) — Braze filler producers (e.g. Höganäs/Wall Colmonoy/Lucas-Milhaupt class data) (2023)
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.