ВЛИЯНИЕ ЭЛЕКТРОСТАТИЧЕСКОГО ПОЛЯ НА ПРОЦЕСС ЛАЗЕРНОЙ ТЕРМООБРАБОТКИ МЕТАЛЛОВ

Abstract

Modern methods of laser processing of the materials are actively introduced into production. However, their wide application in engineering is hampered by the high energy intensity of the processes and the unexplored complex high-speed processes of such processing technologies. This paper covers the hybrid laser technologies for processing materials, in particular, laser-field hardening of metals. The theoretical study of laser interaction with metal is carried out; it is shown that the laser radiation reflection index and the depth of its penetration depend on the electrical conductivity of a skin layer. The study determined the main interrelations between the quality parameters of a treated layer and the parameters of the laser-field technological complex. The paper gives the results of the study on hybrid laser-field hardening of steels widely used in engineering (Steel 10, Steel 45, and Steel 65G) in the electrostatic field. It is shown, that the electrostatic field superposition on a treatment zone leads to the increase in the depth and hardness of a hardened layer through the directed motion of electrons deep into metals. The authors offer a mathematical model for the temperature field distribution in metal under the influence of laser radiation that considers the electrostatic field superposition and allows investigating the dynamics of the hybrid laser hardening. The limitation of the increase in the rate of material cooling by the electrons directional motion in the electrostatic field is mathematically substantiated. The specific values of the electrostatic field influence coefficient are calculated. It is shown, that when superposing the external field, the threshold, critical value of the density of the laser radiation power causing the melting of the treated surface increases. The authors offer the specific mathematical models to be used when preparing a production for determining the required laser radiation power and the strength of the electrostatic field. Based on the results of the study, the principal process scheme is offered, and the laser-field technological complex facility is designed and manufactured.