Nickel Alloy BNi-10 DIFF-HT
Heat-treated state
UNS N99622 · ISO B-Ni10
DIFF-HT = brazed + diffusion heat treated
Pick when a post-braze diffusion/solution cycle is used to break up centreline borides and raise joint ductility and creep life.
Values for the DIFF-HT condition
Other BNi-10 tempers and conditions
BNi-10 is listed in 2 conditions; see the grade overview at BNi-10.
- AS-BRAZED
- DIFF-HT
Compare all 2 conditionsHide
| Condition · open for datasheet | Best for | Yield MPa | Tensile MPa | Elong. % | Hardness | Conductivity |
|---|---|---|---|---|---|---|
As-brazed joint (vacuum, 1149–1204 °C) | Reference condition for joint design data straight out of the vacuum furnace without post-braze diffusion cycle. | 500 | 550 | 1 | 47 HRC | 1.6 % IACS |
DIFF-HTThis page Brazed + diffusion heat treated | Pick when a post-braze diffusion/solution cycle is used to break up centreline borides and raise joint ductility and creep life. | 540 | 650 | 2.5 | 40 HRC | 1.8 % IACS |
What is BNi-10 DIFF-HT?
BNi-10 DIFF-HT is BNi-10 heat treated to DIFF-HT — pick when a post-braze diffusion/solution cycle is used to break up centreline borides and raise joint ductility and creep life. BNi-10 DIFF-HT has a tensile strength of 650 MPa (94.3 ksi), weaker than 65% of nickel alloy grades. Elongation at break is 2.5% and the elastic modulus is 200 GPa (29 Msi). BNi-10 DIFF-HT has a density of 9.1 g/cm³ (0.329 lb/in³), heavier than 94% of nickel alloy grades. It melts at 971°C (1,780 °F).
Advantages
- Conducts heat well — 22 W/m·K (12.7 BTU/hr·ft·°F), better than 91% of nickel alloy grades
- High service temperature — 1,010°C (1,850 °F), better than 82% of nickel alloy grades
Limitations
- Difficult to machine — 8/100, worse than 96% of nickel alloy grades
- Limited ductility — 2.5%, worse than 94% of nickel alloy grades
- High embodied carbon — 16 kg CO₂/kg, worse than 93% of nickel alloy grades
- Difficult to weld — 12/100, worse than 90% of nickel alloy grades
- Needs corrosion protection — 60/100, worse than 89% of nickel alloy grades
BNi-10 DIFF-HT properties
Typical room-temperature values for BNi-10 DIFF-HT; 22 are specific to this condition. Other listed values are BNi-10 reference data and may not represent this condition. Bars are the position among nickel alloy grades.
Physical3
BNi-10 DIFF-HT has a density of 9.1 g/cm³ (0.329 lb/in³), heavier than 94% of nickel alloy grades. It melts at 971°C (1,780 °F).
Mechanical7
BNi-10 DIFF-HT has a tensile strength of 650 MPa (94.3 ksi), weaker than 65% of nickel alloy grades. Elongation at break is 2.5% and the elastic modulus is 200 GPa (29 Msi).
Thermal5
BNi-10 DIFF-HT is rated for continuous service to 1,010°C (1,850 °F). It conducts heat at 22 W/m·K (12.7 BTU/hr·ft·°F), better than 91% of nickel alloy grades. Thermal expansion is 12 µm/m·K (6.67 µin/in·°F).
Electrical2
BNi-10 DIFF-HT has an electrical resistivity of 9.8×10⁻⁷ Ω·m.
Chemical & Environmental2
Corrosion resistance is good (60/100), worse than 89% of nickel alloy grades.
Sustainability3
Producing a kilogram of BNi-10 DIFF-HT takes about 210 MJ of energy and emits 16 kg of CO₂ — more than 81% of nickel alloy grades. Typical recycled content is 10%.
Manufacturability3
BNi-10 DIFF-HT's machinability is not recommended (8/100, worse than 96% of nickel alloy grades); weldability not recommended (12/100).
Values are nominal handbook figures for design screening. Confirm any required mill or lot documentation when quoting.
Working with BNi-10 DIFF-HT
Is BNi-10 easy to machine?
Solidified BNi-10 is boride-hardened and effectively unmachinable by turning/milling — dress fillets by grinding, EDM or belt finishing.
Can BNi-10 be welded?
Not a weldable structural alloy; do not fusion weld the braze deposit (hot cracking) — remachine and re-braze instead.
Can BNi-10 be formed, bent or molded?
Supplied only as powder, paste, tape or pre-sintered preform because the high B/Si/C content makes wire drawing or rolling impossible.
What surface finishes work on BNi-10?
Braze in high vacuum (10⁻⁴ mbar) or dry hydrogen at 1149–1204 °C with 0.05–0.10 mm gap (or blended preform for wide gaps); no flux, and avoid plating over unfinished fillets.
BNi-10 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 | 10 – 13 | 11.5 |
| Wprovides high-temperature strength | 15 – 17 | 16 |
| Bmelting-point depressant; diffuses into base metal | 2.75 – 3.5 | 3.1 |
| Si | 3 – 4 | 3.5 |
| Fe | 2.5 – 4.5 | 3.5 |
| C | 0.4 – 0.55 | 0.47 |
| P | ≤ 0.02 | — |
| S | ≤ 0.02 | — |
| Al | ≤ 0.05 | — |
| Ti | ≤ 0.05 | — |
| Zr | ≤ 0.05 | — |
| Others (total)max, per AWS A5.8 | ≤ 0.5 | — |
| Nibalance, ~62–66 % | balance | — |
BNi-10 DIFF-HT — frequently asked
What is BNi-10 DIFF-HT used for?
BNi-10 DIFF-HT is typically used for wide-gap turbine component brazing, superalloy repair and high-temperature structural joints. In short: W- and Mo-strengthened braze filler; wide-gap superalloy repair; preform and paste forms only.
What is the tensile strength of BNi-10 DIFF-HT?
BNi-10 DIFF-HT has a typical tensile strength of 650 MPa (94.3 ksi) — weaker than 65% of nickel alloy grades. Strength varies by condition: see the 2 listed tempers.
Is BNi-10 DIFF-HT easy to machine?
Not especially — machinability is rated not recommended (8/100, worse than 96% of nickel alloy grades). Solidified BNi-10 is boride-hardened and effectively unmachinable by turning/milling — dress fillets by grinding, EDM or belt finishing.
Can BNi-10 DIFF-HT be welded?
Not readily — weldability is rated not recommended (12/100). Not a weldable structural alloy; do not fusion weld the braze deposit (hot cracking) — remachine and re-braze instead.
What surface finishes work on BNi-10 DIFF-HT?
Braze in high vacuum (10⁻⁴ mbar) or dry hydrogen at 1149–1204 °C with 0.05–0.10 mm gap (or blended preform for wide gaps); no flux, and avoid plating over unfinished fillets.
Can BNi-10 DIFF-HT be formed, bent or molded?
Supplied only as powder, paste, tape or pre-sintered preform because the high B/Si/C content makes wire drawing or rolling impossible.
What is the maximum service temperature of BNi-10 DIFF-HT?
BNi-10 DIFF-HT is rated for continuous use to about 1,010°C (1,850 °F). Strength falls off well before that limit — check the elevated-temperature data for load-bearing parts.
Sources
- AWS A5.8M/A5.8 — Specification for Filler Metals for Brazing and Braze Welding — American Welding Society (2019)
- ASME BPVC Section II Part C, SFA-5.8 — ASME (2023)
- ASM Handbook Vol. 6 — Welding, Brazing and Soldering (Nickel-base brazing filler metals) — ASM International (1993)
- Nickel braze powder/paste datasheets (Ni-Cr-W-B-Si wide-gap grades) — Various braze filler producers (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.