20.500.12556/RUL-190083 Primerjalna analiza vnesenega in povračljivega mehanskega dela pri različnih načinih obremenjevanja superelastične zlitine Nitinol Comparative analysis of input and recoverable mechanical work under different loading modes in a superelastic Nitinol alloy V magistrskem delu preučujemo energijski in elastomehanski odziv preizkušanca iz superelastične zlitine Nitinol. Preizkušanec smo obremenjevali natezno, tlačno in vzvojno z večosnim statičnim in dinamičnim preizkuševališčem, odziv pa beležili s sistemom za digitalno korelacijo posnetkov (DIC). Zajete podatke smo izvozili v Microsoft Excel (MS Excel) obdelali s programskim orodjem Wolfram Mathematica (WM). Obdelava je vključevala določitev obremenjevalnih ciklov, zapis v koordinatnem sistemu, transformacijo koordinatnega sistema iz globalnega kartezičnega naprave za zajem podatkov v cilindričnega lokalnega preizkušanca ter preračun dela in napetostno-deformacijskega odziva preizkušanca. Z napetostno-deformacijskim odzivom v stranskih smereh smo ugotovili najprimernejše podatke za vrednotenje v glavni smeri. S primerjavo vnesenega in povrnjenega mehanskega dela smo ugotovili, da se je za energijsko najbolj reverzibilno izkazalo vzvojno obremenjevanje, za najmanj reverzibilno pa natezno, medtem ko je bila disipacija energije pri tlačnem obremenjevanju nekoliko manjša, vendar primerljiva s tisto pri nateznem obremenjevanju. Pri nateznem obremenjevanju smo prepoznali povezavo med napetostno-deformacijskima odzivoma σ$_{zz}$(ε$_{zz}$) in σ$_{zz}$(ε$_{φφ}$), pri tlačnem obremenjevanju smo prepoznali uklon in vsem napetostno-deformacijskim odzivom pripisali paralelogramski reološki model. V primerjavi z literaturo smo praviloma ugotovili nižje vrednosti elastičnih modulov rezultatov. Pri tem smo izpostavili značilnosti metodologije obdelave podatkov s sistemom za DIC. In this master’s thesis, the energy-related and elastomechanical response of a specimen made of the superelastic alloy Nitinol is investigated. The specimen was subjected to tensile, compressive, and torsional loading using a multiaxial static and dynamic testing system, while the response was recorded using a Digital Image Correlation (DIC) system. The acquired data was exported to Microsoft Excel (MS Excel) and further processed using the Wolfram Mathematica (WM) software environment. The data processing procedure included the identification of loading cycles, representation in a coordinate system, transformation of the coordinate system from the global Cartesian system of the data acquisition device to the local cylindrical coordinate system of the specimen, and the calculation of work and the stress–strain response of the specimen. Based on the stress–strain response in the transverse directions, the most suitable data for evaluation in the principal direction were identified. By comparing the input and recovered mechanical work, we found that torsional loading exhibited the highest degree of energy reversibility, while tensile loading exhibited the lowest. The energy dissipation under compressive loading was slightly lower but comparable to that under tensile loading. During tensile loading, a correlation between the stress–strain responses σ$_{zz}$(ε$_{zz}$) and σ$_{zz}$(ε$_{φφ}$) was observed, while during compressive loading, buckling was identified. Furthermore, the parallelogram rheological model was assigned to all stress–strain responses. In comparison with literature, the values obtained of the elastic moduli were generally lower. In this context, we highlighted the specific characteristics of the data-processing methodology based on the DIC system. superelastičnost nitinol popis dela napetostno-deformacijski odziv paralelogramski model superelasticity nitinol energy balance stress-strain response parallelogram model true false false [P. Hrastar] Slovenski jezik Angleški jezik Magistrsko delo/naloga 2026-10-22 08:30:24 2026-10-22 08:30:36 2026-10-26 11:58:48 0000-00-00 00:00:00 2026 0 Ljubljana 0 XXII, 84 str. 0000-00-00 NiDoloceno NiDoloceno NiDoloceno 0000-00-00 0000-00-00 0000-00-00 620.17:669.245(043.2) 294353 302488835 51251.pdf 51251.pdf 1 FC2DDDCE1BFB9C88430389FA28063B00 17aa70d57f663365c248f775e9e73a58b5c7d70de00cb0a2ca80d8cb72b837f3 19c1f036-cde2-11f1-aea2-0050569b8976 https://repozitorij.uni-lj.si/Dokument.php?lang=slv&id=251113 Fakulteta za strojništvo 0 0 0