BrazeLet® Ni9P-9002

Nickel-based brazing alloy

The nickel-based brazing alloy BrazeLet BNi9 provides high strength joints when brazing stainless steel materials in vacuum or protective atmospheres (dry hydrogen or argon). The brazing alloy is typically used for brazing nickel-based superalloys and stainless steel components where high elevated temperature strength is important, such as gas turbines and solid-oxide fuel cells. It is well suited for repair brazing and diffusion brazing as B readily diffuses into the base materials leaving a ductile Ni-Cr matrix in the joint.

The brazing paste BrazeLet Ni9P-9002 is typically in use for printing thin paste layers of about 0.05 – 0.2 mm on flat plates, on top of structured plates or fins by use of screens or stencils. A typical application is the printing on parts for flat heat exchangers. The use of rubber squeegees is recommended. Reliable printing requires a precise positioning fixture combined with the use of vacuum table or clamping device. Typical printing speed is 300 mm/s. Thin printing lines should have a width of >0.3 mm, small dots diameter should be >1 mm. The solvent based brazing paste BrazeLet Ni9P-9002 increases productivity wherever drying of the paste is an issue. The paste has no settlement, and no stirring is required in the equipment. However, when opening a can from stock it is always recommended to stir the paste.

The printed parts can be dried with standard drying process (hot air) at 120 – 170 °C. The drying time varies depending on thermal mass, design of the parts and the used furnace and needs to be established. After drying, the paste has excellent adhesion to the metal sheet.

     
 

Nominal composition: Ni – 15Cr – 3.6B
Powder type: Gas atomised
Melting range: 1055 °C
Minimum brazing temperature: 1100 °C
Recommended gap clearance: 30 – 100 µm
Applicable specifications: ISO 17672 Ni612, AWS A5.8M/A5.8 BNi-9, ISO 3677 B-Ni81CrB-1055

Solvent type: Oil
Metal content: 90 wt%
Particle size: <63 µm
Recommended drying temperature: 120 – 170 °C (250 – 340 °F)
Evaporation temperature of binder: 350 – 450 °C (660 – 840 °F)
Typical Brookfield viscosity (2.5 rpm @ 20 °C): 300 Pas (T-spindle D)
Typical density: 4.0 g/cm3 

 
     

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