Pribory i Metody Izmerenij (Mar 2015)
DISLOCATION AVALANCHES AND STRAIN BURSTS IN THE BOARDS OF RADIO-ENGINEERING EQUIPMENT
Abstract
The aim of this work is to investigate the influence of vibrations on the material of the board. For that purpose a cascade of navigation devices boards was installed on the vibrational stand. Experiments were performed in the 0,5–10 Hz vibrational diapason range; 0–3 V voltage range; 0 – +45 °C allowed temperature range. Amplitude method was applied to determine the coordinates of localized sources of acoustic emission. The results indicate the initial increase in tension and relative deformation and further their decrement. Growth rate reduction of mechanical stress dσ/dε is due to destruction of material structure. The receiving piezo converter based on ЦТС-19 ceramics and a waveguide that was in acoustic contact with the sample were used during experiments. The acquired experimental data on acoustic emission reflect the formation of microdefects and the instability of mechanical tension, its avalanche and explosive tendency in the material when the microvolumes of material are torn.
