Sintering and Electron Emission Properties of Impregnated Cathode by HIP Method

Abstract

An impregnated cathode was manufactured by Hot Isostatic Pressing (HIP) with the mixed powders of W and electron emissive material.
The effect of the HIP parameters on the sintering condition was investigated using SEM, X-ray diffraction and density measurement, and the relation between sintering condition and emission properties was discussed. The results were as follows;
The densification was accelerated with increasing of HIP temperature and HIP holding time. As densification advanced, reaction between W and electron emissive material was progressed, resulting in decreasing of effective components and increasing of ineffective components of the emission properties. On the other hand, as the densification advanced, the better emission properties were obtained. We consider the emission properties depends rather on the contact area of W and electron emissive material than the amount of effective components.