Why flux is in demand:
The inclusions and gas are produced during the aluminium melting process. This will have a bad impact on the quality of ingots and other relative aluminum products. Oxides, carbides, borides are the commonly seen inclusions. Al₂O₃ and MgO greatly contaminates the molten aluminum seriously. The inclusions existed as gas carrier, increasing much more gas in aluminum alloy, cause the casting defects of porosity and slag inclusions.In additional, the impurities in the charge for aluminum smelting also can bring in certain harmful substances, for example, the alkali metal (Na, Ca, Li ) and so on. These harmful substances reduce the physical and chemical properties. Sodium can easily cause the “sodium brittle” if in the high magnesium aluminum alloy and reduce the fluidity of the molten aluminum. Thus, the amounts of slag inclusions, gas, impurities existed in the molten aluminum are strictly be stipulated.
To slove the above problems, Granular fused refining fluxes was developed and start to play an important role in the aluminum melt refining process.
A must-know of flux :
Degassing is to remove the gas from the melt.
Refining is to remove the inclusions from the melt.
Refining and Degassing is to remove or lower the inclusions down to a minimum amount. Thus the ideal purification effect of the metal can be achieved.
Impurities refer to alkali meatals (sodium, calcium, lithium
Dross or Slag refer to non-metallic inclusions (oxides, carbides, borides)