The Mechanism of Current Flow in Composite Alumochromiun Ceramics during Its Electron Beam Sintering in a Forevacuum

It is shown that during electron beam sintering in the forevacuum pressure region of powder components of composite Al₂O₃–Cr ceramics, the magnitude of the current flowing through the sample depends both on the percentage of chromium and on the heating temperature of the sample. When a certain temperature is reached, the process of current flow is influenced by thermoelectric emission from the sample surface. Along with the ions from the beam plasma, a noticeable thermoelectric emission current contributes to the process of neutralizing the charging of the ceramic surface with an electron beam and reduces the absolute value of the negative potential of the sample surface. This ultimately contributes to an increase in the efficiency of energy transfer from the electron beam to the sample.