Uniform Particle BNi?2 Powder forBrazing Production
Method B: Dry powder filling (for complex shapes & localrepair)
Fix components, spread BNi?2 powder evenly along joint gaps. Removeexcess powder; use stoppers to prevent flow-out at hightemperature.
3. Vacuum Brazing Thermal Cycle
1. Pump furnace vacuum ≤5×10?3 Pa.
2. Binder burnout (for paste): hold at 600–900 °C for 20–60 min toremove organic residues.
3. Heat up at 5–15 °C/min.
4. Brazing hold: 1050–1100 °C, hold 10–30 min. BNi?2 solidus 970°C, liquidus 1000 °C. Extend holding time for aerospace parts fordiffusion treatment.
Common sizes: -200 mesh, -300 mesh, -325 mesh, or customizedmicrons
5. Typical Applications
Aerospace:? jet engine structural members, turbine components,compressor vanes, stators, honeycomb structures, seals
Energy & turbines:? gas turbine parts, heat exchangers, EGRcoolers, nuclear e outside the core
Stainless steel & superalloy joining:? austenitic/martensiticstainless steel, Inconel, Hastelloy, cobalt alloys
Cutting tools & wear parts:? brazing diamond segments, tungstencarbide inserts, cemented carbide tools
Automotive & e-mobility:? turbocharger parts, stainlesscooling-system components, li plates, heat-exchangerassembliesRite Material
Degrease with acetone or suitable solvent
Remove scale, oxide, and fingerprints
Even tiny oil traces can cause voids, skipping, or weak joints
3. Use the right atmosphere
BNi-2 is made for vacuum, high-purity argon, or very dryhydrogen.
Air furnaces are not recommended
Poor atmosphere → chromium oxidation, black joints, poorwetting
No flux needed in vacuum brazing
BNi-2 Nickel-Based Brazing Powder — Full EnglishIntroduction
1. Overview
BNi-2 is one of the most widely usednickel-chromium-silicon-boron-iron brazing alloys. It is commonlysupplied as gas-atomized spherical powder, paste, foil, or preform,and conforms to AWS A5.8 BNi-2, SAE AMS 4777, ISO 17672 Ni620 / Ni620, and UNS N99620.
It is designed for high-temperature joining? of stainless steels,nickel-based superalloys, cobalt-based alloys, and selectedhardmaterials, with relatively low brazing temperature andexcellent joint integrity.
2. Nominal Chemical Composition (wt%)
Nickel (Ni):? Balance
Chromium (Cr):? 6.0–8.0 %
Silicon (Si):? 4.0–5.0 %
Boron (B):? 2.75–3.50 %
Iron (Fe):? 2.5–3.5 %
Carbon (C):? ≤ 0.06 %
Phosphorus (P):? ≤ 0.02 %
Sulfur (S):? ≤ 0.02 %
Other impurities: tightly controlledRite Material
High Pressure Part BNi?2 Powder for Brazing Joints