Scandia doped tungsten matrix for impregnated cathode

Abstract

As a matrix for Sc-type impregnated cathode, scandia doped tungsten with a uniform distribution of Sc 2O 3 was obtained by powder metallurgy combined with the liquid-solid doping method. The microstructure and composition of the powder and the anti-ion bombardment behavior of scandium in the matrix were studied by means of SEM, EDS, XRD, and in-situ AES methods. Tungsten powder covered with scandium oxide, an ideal scandium oxide-doped tungsten powder for the preparation of Sc-type impregnated cathode, was obtained using the liquid-solid doping method. Compared with the matrix prepared with the mechanically mixed powder of tungsten and scandium oxide, Sc 2O 3-W matrix prepared with this kind of powder had smaller grain size and uniform distribution of scandium. Sc on the surface of Sc 2O 3 doped tungsten matrix had good high temperature stability and good anti-ion bombardment capability.