Analysis of material condition of side frames of freight trucks before and after thermal hardening was performed by combined analysis of Acoustic Emission (AE) and strain diagrams during tests of samples cut from the frames. The kinetic of damage accumulation during loading to failure in the material after normalizing or volume-surface hardening was analyzed. Changes in ductility and toughness resource of the metal was evaluated.
Keyword: acoustic emission
The EA Signal tests registered during the static stretching of the X6CrNiTi18-10 steel (according to EN 10088) have been o included in the work. The tests were done in the room temperature and in the high temperature of – 400 C on the universal strength (tensile) machine ZDM-5 with the range of 0-50 kN equipped with the digital registration of the strength and stretching. The analysis of the EA signal intensity has been conducted, depending on the deformation of the sample and test temperature. On the basis of the EA signal there have been the own characteristic oscillation frequencies of the samples designated, being the effect of the degradation of the structure as a result of the increased load.