20.500.12556/RUL-158479 Določanje popustnih karakteristik orodnega jekla D2 Determining the tempering characteristics of D2 tool steel Eksperimentalna raziskava zajema vpliv spreminjanja medija gašenja, temperatur popuščanja in števila ciklov popuščanja na orodno jeklo za delo v hladnem D2. Namen raziskave je bila ugotovitev optimalnih parametrov toplotne obdelave za dosego želene trdote materiala s hkratnim ozirom na nekatere ostale mehanske lastnosti jekla. V eksperimentalnem delu smo pripravili serijo vzorcev orodnega jekla D2, ki smo jih kalili z dvema različnima medijema gašenja in nato večkrat popuščali na različno visokih temperaturah. Po vsakem koraku toplotne obdelave smo vzorcem pomerili trdoto z metodo Rockwell C. Na koncu toplotne obdelave smo vzorcem izmerili tudi zaostale napetosti po metodi rentgenske difrakcije ter pod optičnim mikroskopom analizirali razlike v mikrostrukturi. Ugotovili smo, da je optimalna temperatura popuščanja 550 °C, saj trdota jekla pri popuščanju na višjih temperaturah pade, njegove mehanske lastnosti pa bodo pri nadaljnji uporabi do delovnih temperatur 550 °C odporne na spremembe. Experimental research contains the impact of changing the quenching medium, tempering temperatures and the number of tempering cycles on the tool steel D2. The purpose of this research was to determine the optimal parameters of heat treatment to achieve the desired hardness of the material with regard to some other mechanical properties of the steel. In the experimental part, we prepared a series of samples of tool steel D2, which were quenched with two different quenching media, and then tempered several times at different temperatures. After each heat treatment step, the hardness of the samples was measured using the Rockwell C method. At the end of the heat treatment, the samples’ internal residual stress levels were measured using the X-ray diffraction method and the differences in the microstructure were analysed under an optical microscope. We found that the optimal tempering temperature is 550 °C, as the hardness of the steel decreases during tempering at higher temperatures, and its mechanical properties will thus be resistant to changes during further use up to 550 °C. orodno jeklo D2 toplotna obdelava kaljenje popuščanje trdota zaostale napetosti tool steel D2 heat treatment hardening tempering hardness internal residual stress true false false [J. Jakše] Slovenski jezik Angleški jezik Diplomsko delo/naloga 2024-06-14 08:30:30 2024-06-14 08:30:39 2024-07-22 11:29:24 0000-00-00 00:00:00 2024 0 Ljubljana 0 XI, 39 str. 0000-00-00 NiDoloceno NiDoloceno NiDoloceno 0000-00-00 0000-00-00 0000-00-00 620.17:621.78:621.785.796(043.2) 260170 202427139 33291.pdf 33291.pdf 1 EF6CD04D595311B15DDA0BDFCD50C9D9 5ae788a2f9c71effe5206c188f14c156a613e0dd30ae0ed4278cc9c5a9fd2c29 a11dd118-2a17-11ef-86fa-0050569b8976 https://repozitorij.uni-lj.si/Dokument.php?lang=slv&id=186121 Fakulteta za strojništvo 0 0 0