Investigation of the Portevin-Le Chatelier effect in metals under additional vibration impact by using the DIC-technique and the IR-analysis

摘要

In the present work, the deformation processes and local heating were analyzed by the digital image correlation technique and the infrared thermography accordingly to characterize the spatial-time inhomogeneity associated with the Chemov-Luders behavior and the Portevin-Le Chatelier (PLC) effect in metals. To estimate the influence of the additional vibration impact on the serrated flow, the set of flat dog-bone specimens and thin-walled cylindrical specimens were deformed in tension with a biaxial servo-hydraulic testing system Instron 8850 and with additional vibration impact provided with a tensile load and a frequency of 4 Hz with a sinusoidal waveform. The results show the influence of additional cyclic loading on the spatial-time inhomogeneity of the plastic flow in metals, it is reduced the quasi-periodic character of the plastic flow.