HZ-QJ208 flux is a  fine white powder consisting of a mixture of potassium fluroroaluminate salts which is non-corrosive and non-hygroscopic.

The flux of the highest quality and consistency is produced under stringent process tolerances and a variety of quality control procedures by us.

The flux has a melting point range of 560°C to 574°C, just below the eutectic temperature of the Al-Si brazing alloy.

The particle size lies in the range of 1um to 5um. 

During the brazing process the flux dissolves the oxide layer on aluminum and allow the filler metal to flow freely into the joints by capillary action.

After cooling, the flux residue remains on the surface as a thin adherent film and is non-corrosive and non-hygroscopic.

The flux does not require post brazing treatment of the joint area.

BRAZING PROCESS

 1. Cleaning : the surface to be brazed must be pre-cleaned to achieve a water wettable surface.

 2. Flux application : usually as a water based slurry. Typical the slurry concentration is in the range of 3% to 25%.

 3. Drying : To achieve a successfully brazed component it is essential that all water is removed from the flux coating. 

A drying process is carried out at approximately 180°C - 250°C.

 4.The process requirement of brazing furnace: 

     - Inert atmosphere - usually nitrogen as this is the cheapest. 
     - Dewpoint less than minus 40°C.
     - Operating temperature range of 575-620°C, coinciding with the melting point of  the cladding.
     - Rate of heating of the component greater than 20°C per minute.