Vacuum determination of Hydrogen in Steels

The Physical properties of plain carbon and alloy steels are adversely affected by the presence of gases such as oxygen, nitrogen and hydrogen. Hydrogen is most difficult to control because of its ready diffusibility into molten steel. This offers a great difficulty in sampling and analysis of liquid steel for hydrogen. Hydrogen exists in steel chiefly as interstitial solid solution (i.e. in atomic dispersion) and perhaps to some extent as hydrides that are unstable and decomposes to form atomic hydrogen.