Supporting products for aluminium brazing
Wetting agent as suspension additives
NOCOLOK® SURF 225 is a biodegradable linear alcohol EO/PO. It is a low foaming non-ionic with excellent hard surface detergency combined to wetting properties. It is soluble in water and most organic solvents except paraffinics. It is stable in acidic and alkaline solutions and can be used as a rinse aid for commercial dishwashing or miscellaneous industrial applications. Compliant with the EU's detergent biodegradability regulation.
Application
- Low foaming surfactant for brazing flux suspensions (up to 50 °C)
- Recommended concentration: 0.1 to 0.2 %
For use in brazing processes
As the name of this product type indicates, Flux-Green-Filler-Stop (GFS) “stops” molten brazing filler metal from flowing into areas where it is unwanted, thus keeping it “stopped” so that the surfaces remain clean and free from the presence of any filler metal.
Brazing filler metals do not like to bond with, or flow over, any dirt, grease, or oxides so the presence of any of these contaminants on the surface of parts to be brazed can prevent the filler metal from flowing over surfaces where these contaminants are located.
Therefore, GFS compounds are very effective at preventing molten filler metal flowing into protected areas. The GFS compounds are mixed with a liquid carrier solution to form and can be applied onto metal surfaces by using a small brush or by spraying or dipping.
Main features
- To prevent brazing filler metal from flowing over, bonding to or any protected surfaces
- To prevent the contamination of base or filler metal
- To prevent a sintering of stacked parts during furnace brazing
- To be used on any type of metal and in any type of brazing process
- To run as a masking agent when thermal spraying metallic coatings
- To make heat-resistant marks for identification purposes
Used in a mixture to improve adhesion of the flux coating
NOCOLOK® Precoating can be used in mixture with NOCOLOK® Flux or NOCOLOK® Zn Flux and water to improve adhesion of the flux coating. The system can be applied on external and internal surfaces in order to reduce flux fall-off and dust formation on handling of flux coated components.
Proper application of the Precoating/water/flux system shows no negative effects regarding the appearance of the post braze aluminium surfaces, compared to the use of pure NOCOLOK® Flux or pure NOCOLOK® Zn Flux (especially no discoloration effects).
- Suitable application methods:
spraying, dipping or brushing - Surface temperature:
> 10 °C, with subsequent drying step - Recommended thickness of the coating:
10 – 30 μm