Experimental studies of zirconium/aluminum getter pumps

Getters of the type to be utilized as tritium pumps in the foreline of the TFTR torus vacuum system, and presumably in those of the neutral beam injector arms, were evaluated using hydrogen and deuterium. The capacity and speed as rated by the manufacturer (SAES) are found to be conservative. In addition, the getters are shown to continue to pump hydrogen even in the presence of chemically active, impurity gases, provided the getter temperature is maintained at >3000C. Since hydrogen pumping is reversible, the getters can be used over and over again after reactivation to release the previously pumped hydrogen. By operating a tungsten filament to crack methane, and using the getter to pump the hydrogen produced, relatively high speed and capacity for methane is demonstrated