Equilibrium pressures of H2 and D2 for different getter materials and the effect of CO impurities

Abstract

The 84% Zr–16% Al nonevaporable getter alloy has been used for a long time in vacuum technology and, more recently, has been adopted in advanced applications such as fusion technology and particle accelerators. A new getter material consisting of a Zr–V–Fe ternary alloy having interesting characteristics for these applications has also been proposed. Particularly in fusion technology hydrogen and its isotopes must be sorbed in relatively large amounts. Therefore, the equilibrium pressures of H2 and D2 have been investigated for the above mentioned alloys as well as for the more traditional getter material, titanium. A temperature range from 500 to 800 °C at pressures less than about 100 Pa has been covered. Moreover, as the hydrogen isotopes will contain various gaseous impurities, of which carbon monoxide is usually the most important, the effects of this gas on the H2 and D2 equilibrium pressures have also been investigated.