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A complex method for analyzing the processes in the systems of indirect cathode heating for electron- beam welding guns is proposed. The necessity of considering the electron-beam formation process in a cathode assembly with predetermined geometric characteristics is justified for calculating the distribution of the heat-flux density over the main-cathode surface. The typical distribution of the heat-flux density over the surface of the main cathode, which is heated via electron bombardment using a spiral wire heater, is analyzed. A method for calculating the temperature distribution over the structural elements of a typical cathode assembly is described, and the calculation results are analyzed. The influence of the nonuniformity of the electronbeam- current density distribution over the heated surface of the main cathode and the heat dissipation on the temperature and emission-current-density distributions on the working surface of the main cathode is considered. The advantages of the proposed method in comparison with existing idealized mathematical models and its suitability for solving problems of designing various electron guns are demonstrated.

An express method of direct measurements of the current density distribution of axially symmetric electron beams is proposed. It is shown that use of the technique is urgently needed to improve the reproducibility of the results of electron-beam processing. Comparative analysis of existing methods to measure the parameters of electron beams used for technological purposes is carried out. A technique to restore a radial distribution of electron beam current density as well as a device to implement the technique is developed. The results of radial distribution recovery are analyzed in the case in which the initial distribution is given in the form of a model function of normal distribution. An algorithm to determine estimated sizes of the area within which spatial distribution discretization is carried out is developed. Based on analysis of the experimental dependences, it is shown that the suggested numerical method can be applied to all types of axial-symmetric distributions. The nature of errors occurring after distribution function recovery is analyzed. A technological projection of express diagnostic systems for the processing electron beams is made taking into account parameters of the existing element base.

Means of improving the performance of ore-heating furnaces are considered. A method of calculating the thermal conditions in the furnace is proposed. This method permits automatic monitoring of the state of the lining. A regression model permits the construction of an automated control system for the ore-heating furnace.