Why is the Hydrogen detection analyser important in an aluminium foundry or cast house?
Hydrogen forms whenever molten aluminium comes into contact with water vapour, and easily dissolves into the melt. The gas tends to come out of the solution and forms bubbles when the melt solidifies.
The detrimental effects arising from the presence of an excess of dissolved hydrogen in aluminium are numerous.
Hydrogen causes porosity in aluminium products leading to many casting defects, reduced mechanical properties like fatigue and lower corrosion resistance. Several methods are used to reduce the amount of dissolved hydrogen from the melt, such as furnace fluxing prior to the casting process or using in-line degassing equipment during the casting process.