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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.

A brief review of present day getter materials is made with reference to the two principal families, i.e., evaporable and nonevaporable getters. The main physicochemical processes involved in the gettering process are reviewed in order to establish the concept of gettering-selective chemical pumping. Examples of practical getter devices are described in connection with a brief overview of some of the most common applications. However, most emphasis will be placed in describing some of the most advanced and more unusual applications of getters which may not always be in widespread use but which indicate the versatility of gettering in widely differing fields.

Nonevaporable getters have been widely used for many years in sealed vacuum or controlled atmosphere devices. They are also finding applications in other fields, where specific characteristics are required and tailor-made getters are requested, in some cases sacrificing speed in favor of lower activation temperatures, or lower operating temperature, while still maintaining an adequate sorption capacity. With these objectives, a decade long research project was undertaken which involved investigation of Zr–V–Fe alloys. The physico-chemical properties and the gettering characteristics (speed and capacity) of this family of alloys for some main gases usually present in vacuum devices (H2, CO, N2) have therefore been studied in a range of activation temperatures of less than about 700°C. The equilibrium pressure of H2 on these materials has also been studied as a function of concentration and temperature in a range of pressures less than ∠10 Pa. The results obtained, showing the efficiency of this type of alloy as a getter in a range of activation temperatures of about 500°C, are also discussed in comparison with some other well-known getter materials.