La2O3-Gd2O3-Mo secondary emission material

A new kind of materials La2O3-Gd2O3-Mo has been produced by powder metallurgy method. The com-position and microstructure of the material were studied by XRD and SEM. It shows that no chemical reaction takesplace among La2O3, Gd2O3, Mo and the rare earth oxides exist along molybdenum grain boundaries and in thepores. The emission property measurement results of this material show that adding rare earth oxide into molybde-num can improve the secondary emission coefficient of the emitter, and the emission property depends on the activa-ting temperature. After La2 O3-Gd2 O3-Mo was activated at 1360 ℃, the maximum secondary emission coefficient canbe high to 2.62, which has exceeded that for practical uses(2.0).