FLUX 2805


Aluminum-Brazing Flux, Flux 2805 is a non-corrosive, Potassiumfluoroaluminate, controlled atmosphere brazing Flux (CAB).

Physical Properties

  • Appearance: White Powder
    Bulk Density (20°C): approx. 500 kg/ m3
    Melting Point: 550 -560°C
    Odor: Neutral
    Solubility (20°C) Nearly insoluble in water
    pH-value: 5 – 7,5
    Surface area: approx. 1m2/cm3
  • K 29-34%
    Al 14-17%
    F 47-52%
    Fe2O3 max 0.025%
    SO4 max 0.010%
    Si 02 max 0.200%
    Cl max 0.020%
    H2O approx. 3.000%


Flux 2805 is classified as non-hazardous according to current regulations.

Observe usual chemical handling precautions

Please see Safety Data Sheet (SDS) for additional information.


In 25 kg net weight, with interior polyethylene bag.

Can be customized to application.

Particle Size Range

  • Type Ultrafine Fine Medium Coarse
    Particle size (d50) <8 μm 8-10.5 μm 10.5-12.5 μm 12.5-16 μm
    Particle size (d95) <20 μm 20-25 μm 25-35 μm >35 μm

FLUX 2805

Flux 2805 is the superior, non-corrosive, CAB Flux used with confidence by leading manufacturer of brazed aluminum heat ex-changers around the world.

Flux Schweiß -und Lötstoffe USA, LLC produces Potassiumfluoroaluminate with the highest purity offering significant oxide dissolving performance advantages in comparison with other low purity fluxes.

Flux 2805 is designed to have a melting point of 550°C – 560°C allowing a longer period of time for braze surface preparation prior to the melting temperature of filler metals being reached during the CAB process. This has the effect of improving capillary action and filler metal flow.

Highest quality and product consistency is achieved by following strict manufacturing standards in our unique flux manufacturing technique.

Flux 2805 is produced in high concentration with various grain sizes to satisfy every possible requirement from our diverse customer base.

Flux 2805 is used as the active component in our extensive range of non-corrosive flux solutions and pastes including metallized and flame brazing pastes.

Flux 2805:

  • CAB flux
  • Cesium complex can be added
  • Active component in many solutions and pastes
  • Process:

  • Wet Spray
  • Electrostatic
  • Dip
  • Brush
  • Air spray, roll, dispense and other contact methods are used for application of our numerous products using Flux 2805 as the active component.
  • Brazing:
  • Braze as normal (CAB-Process)
  • Benefits of Flux 2805:

  • Cost competitive product
  • Good product wettability
  • Excellent braze surface preparation
  • Improved capillary action
  • Improved cladding flow and braze fillet formation
  • Lowest HF generating flux
  • Conclusion:

    Flux 2805 is the preferred product for use in the CAB brazing of aluminum heat ex-changers by leading manufacturers.

    Flux Schweiß -und Lötstoffe USA, LLC is the leader in fluxing technologies and is continuously developing customer specific solutions to achieve maximum cost benefit in the processing sequence of heat exchange products.