The study of the internal friction of electrolytic coatings is complicated by the impossibility of obtaining sufficiently massive samples and testing them independently of the substrate, and therefore it is necessary to evaluate the stress state of the sample-coating system. The aim of the work was to find a relationship between the internal stresses arising in the coating deposited on a circular cross-section specimen during internal friction tests using a torsion pendulum. During the analysis of the stress-strain state of the bimallic sample, expressions were found to calculate the maximum and minimum stresses in the electrolytic coating. The mutual influence of the coating material and the substrate was evaluated numerically using the Comsol Multiphysics program.
Keywords: internal friction, internal stresses, torsion pendulum, beam rotation, electrolytic coatings
An optical sensor for measuring small displacements and rotation angles is described. Based on a non-contact principle of operation, which can be used to control small movements in installations to determine internal friction by the type of torsion pendulum. The main characteristics of the device are shown and the installation and connection diagram is shown by means of the ADC to the computer
Keywords: optical sensor, angle of rotation, displacement, internal friction, microcontroller, torsional pendulum, photoresistor, signal filtering, signal transmission, non-contact, ADC