Vibroacoustic Monitoring Features of Radiation-Beam Technologies by the Case Study of Laser, Electrical Discharge, and Electron-Beam Machining

Abstract

A feature of radiation-beam technologies is similar processes associated with phase transformations and chemical reactions that cause changes in the volume of matter, accompanied by the vibroacoustic energy release distributed through the equipment flexible system in a wide frequency range (up to 40 kHz and high for 150 ms). The vibroacoustic signal amplitude accompanying radiation-beam technologies depends on the power density and process performance. The accelerated growth of the high-frequency components of the vibroacoustic signal is associated with the activation of the processes of volumetric boiling and evaporation/sublimation of the material. The Kf parameter, introduced as the ratio of the effective amplitudes of the low-frequency and high-frequency ranges of the vibroacoustic signal, monitors the results of high-energy flows’ impact on the material in the direction of vaporization/sublimation. The Kf parameter decrease tendency shows an increase in the proportion of the substance evaporated during laser treatment. The Kf parameter control allows the indication of the short-circuit approach in electric discharge machining, which allows increased productivity and reliability of processing. The monitoring of the Kf parameter helps to select rational processing modes, preventing excessive evaporation, providing the necessary intensity of the impact power to trigger the necessary chemical reactions in surface electron-beam alloying.