Sievert’s law

Sievert’s (square root) law states that, at a given temperature, the solubility of a diatomic gas in a melt changes with the square root of its pressure.

The law is therefore significant for the determination of gas solubility in liquid metal.

According to the law, the concentration of a diatomic gas dissolved in the melt is proportional to its partial pressure on the melt. Eq. 1 can therefore be written for the concentration of the hydrogen dissolved in the melt:

Eq. 1:

C = temperature and alloy-dependent constant; pH2 = hydrogen partial pressure on the melt

The relationship described in Eq. 1 is used, for example, to determine the hydrogen contents in a melt (see also Hydrogen solubility, Hydrogen determination, Chapel process).