2021 №01 (02) DOI of Article
2021 №01 (04)

Technical Diagnostics and Non-Destructive Testing 2021 #01
Technical Diagnostics and Non-Destructive Testing #1, 2021, pp. 17-26

Diagnosis of damage to caterpillar tracks under mechanical loading based on the results of measurements of the coercive force

O.P. Gopkalo1, M.P. Zemtsov1, O.Ye. Gopkalo1, V.Ye. Bodunov1, G.Ya. Bezlyudko2, P.M. Solomacha2
1G.S. Pisarenko Institute for Problems of Strength of NASU. 2 Timiryazevska Str., 01014, Kyiv, Ukraine. E-mail: ips@ipp.kiev.ua
2LLC «Special Scientific Developments», P.O. box 12036, 61184, Kharkiv, Ukraine

Obtained experimental results of 4-point bend tests of caterpillar tracks made of austenitic steel of Gadfield type confirmed the possibility of using non-destructive coercimetric testing to assess the level of metal loading, which characterizes the degree of damage, by measuring coercive force (Hc). Due to the effect of a sharp change in the values of the coercive force when stresses of the conditional yield stress are exceeded, which correspond to threshold values of Hc for the transition from elastic to plastic deformation, there is no need to determine the mechanical characteristics of strength and plasticity of the metal, since diagnosis of the relative loading is carried out with respect to the conditional yield stress. An approximate estimate of the level of loading of tracks metal was performed using the known dependence of the values of coercive force on stresses for austenitic steel AISI 304 and a similar hypothetical dependence for the studied steel. It is established that each stage of 4-point bend loading corresponds to a certain level of relative stresses that characterize the extent of metal damage. The maximum level of sustained damage roughly corresponds to the stress limit of the metal. The results obtained are in good agreement with the data of metallographic studies. 6 Ref., 1 Tabl., 10 Fig.
Keywords: caterpillar tracks, structuroscope, coercive force, load, damage, stress

Received: 23.11.2020


1. Gopkalo, O.P., Nekhotiashchiy, V.O., Bezlyudko, G.Ya., Kurash, Yu.P. (2019) Diagnosis of damage in austenitic steel AISI 304 at mechanical loading by measurements of coercive force. Tekh. Diagnost. i Nerazrush. Kontrol, 4, 12-24 [in Ukrainian]. https://doi.org/10.15407/tdnk2019.04.01
2. Gopkalo, O., Bezlyudko, G., Nekhotiashchiy, V., Gopkalo, O.Ye., Kurash, Yu. (2020) Damage evaluation for AISI 304 steel under cyclic loading based on coercive force measurements. Int. J. Fatigue, Vol. 139. https://doi.org/10.1016/j.ijfatigue.2020.105752
3. Gopkalo, A.P., Bezlyudko, G.Ya., Nekhotiashchiy, V.O. (2017) On expert evaluation of damage of steel AISI 304 at static and cyclic loading by measurements of coercive force. V Mire Nerazrushayushchego Kontrolya, St.-Petersburg, Vol. 20, 45-51 [in Russian].
4. Gopkalo, O.P., Bezlyudko, G.Ya., Kotlyarenko, A.A., Kurash, Yu.P., Solomakha, R.M. (2020) Diagnosis of damage to ferromagnetic steels during mechanical loading by results of measurements of coercive force. Tekh. Diagnost. ta Neruiniv. Kontrol, 2, 13-21 [in Ukrainian].
5. Gopkalo, O.P., Yukhymets, P.S., Bezlyudko, G.Ya., Solomakha, R.M., Nekhotiashchiy, V.O. (2020) From the experience of using non-destructive control methods to assess the technical condition of the pipeline emergency section. Tekh. Diagnost. ta Neruiniv. Kontrol, 3, 30-36 [in Ukrainian]. https://doi.org/10.37434/tdnk2020.03.04
6. Gopkalo, O., Bezlyudko, G., Nekhotiashchiy, V. (2018) Evaluation of the structures metal damage under the static and cyclic loadings according to the coercive force value. Scientific J. of TNTU. 89(1), 19-32. (Mechanics and materials science). https://doi.org/10.33108/visnyk_tntu2018.01.019

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