Different types of fluxes are available for cleaning, covering, element removal, protection against chromium loss and slag coagulation.
They are sold under the brand names ALBRAL, CHROMBRAL, CUPREX*, CUPRIT*, ELEKTRO, ELIMINALU, RAFFINATOR, RECUPEX and SLAX.
The choice of flux depends on alloy types and foundry practice (furnaces, melt process, type of castings, etc.). There are two melting techniques. One method is to melt the alloy under cover of a reducing flux, which protects the metal from the absorption of oxygen. The second method is to melt the alloy under strongly oxidising conditions using an oxidising flux cover to exclude all hydrogen.
It is frequently necessary to protect the surface of a melt in the furnace or ladle to prevent oxidation losses of alloying elements (such as aluminium or zinc) and gas pick-up from the atmosphere or from the combustion of fuels. ALBRAL and CUPRIT fluxes are recommended for this process.
When it is necessary to melt under oxidising conditions, oxidising fluxes or combined covering and oxidising fluxes are available, such as CUPREX.
Fluxes are also required in scrap recovery. When dirty or oxidised scrap is used, it is essential to eliminate as much non-metallic material from the melt as possible and prevent loss of metal in the dross. It is also frequently necessary to recover metal from dross. In these cases RECUPEX or RAFFINATOR fluxes are used.
ELIMINALU 8 is specifically designed to reduce aluminium to a very low level. This flux preferentially reacts with it to form compounds which separate easily by floatation. After the removal of aluminium the flux will act further to reduce silicon and manganese as required.
+ Elimination of gas porosity
+ Elimination of oxides
+ Removal of metallic impurities
+ Effective slag removal