20.500.12556/RUL-171828 Sistem za kriogeno prisilno hlajenje kovinskih nanosov med procesom laserskega ciljnega nanašanja System for cryogenic forced cooling of metal deposits during the laser direct energy deposition process V sklopu zaključne naloge smo nadgradili obstoječi sistem za lasersko ciljno nanašanje kovinskega prahu (DED-LB) s sistemom za kriogeno hlajenje z dušikom. Glavne komponente sistema za kriogeno hlajenje so Dewarjeva posoda z izstopnim ventilom, dovodne cevi in usmerjevalna šoba. Z nadgrajenim sistemom za DED-LB smo poleg nanosov brez hlajenja, z dovodom plinaste ali tekoče faze dušika v neposredno okolico talilnega bazena, izdelali nanose s tremi stopnjami hlajenja. Kot prašnati dodajani material in substrat smo uporabili nerjavno jeklo SS316L in SS304. Za spremljanje procesa DED-LB smo uporabili IR kamero. Karakterizacijo vpliva hlajenja nastalih nanosov smo ovrednotili z EBSD analizo velikosti kristalnih zrn in mikrotrdote po Vickersu. Rezultalti posnetkov IR kamere in analiz mikrostrukture so v nasprotju s pričakovanji pokazali, da z obstoječo izvedbo sistema kriogenega hlajenja ne dosežemo želenega ohlajanja in posledično manjše velikosti kristalnih zrn nastalih nanosov. Med izvedbami nanosov je bil manjši učinek zaznan samo v primeru dovoda tekoče faze dušika. As part of the final thesis, we upgraded the existing system for laser directed deposition of metallic powder (DED-LB) with a cryogenic cooling system using nitrogen. The main components of the cryogenic cooling system are a Dewar vessel with an outlet valve, supply tubes, and a directing nozzle. With the upgraded DED-LB system, in addition to deposits without cooling, we also produced deposits with three levels of cooling. Stainless steel SS316L and SS304 were used as the filler material and substrate. To monitor the DED-LB process, we used an IR camera. The effect of cooling on the resulting deposits was characterized by EBSD analysis of grain size and Vickers microhardness measurements. The results of the IR camera recordings and microstructure analyses, contrary to expectations, showed that with the current design of the cryogenic cooling system, the desired cooling and consequently smaller grain sizes of the resulting deposits were not achieved. The greatest effect on the deposits was a minor effect observed only in the case of supplying the liquid phase of nitrogen. dodajalne tehnologije lasersko nalaganje kovin kriogeno hlajenje tekoči dušik mikrostruktura additive manufacturing laser metal deposition cryogenic cooling liquid nitrogen microstructure true false false Slovenski jezik Angleški jezik Diplomsko delo/naloga 2025-09-03 08:30:35 2025-09-03 08:30:38 2025-09-22 03:40:33 0000-00-00 00:00:00 2025 0 0 XII,41 f. 2025 0000-00-00 NiDoloceno NiDoloceno NiDoloceno 0000-00-00 0000-00-00 0000-00-00 621.791.72:621.762:62-712(043.2) 275201 248244483 43612.pdf 43612.pdf 1 C80F3BB8595AA62B408AC0B06BB5B3C0 2f364ecf0484a0ed7a4b331bcc4e5d3de4518589c7e66c93bb62daab721c5c2d 5d8f2d9e-888f-11f0-9328-0050569b8976 https://repozitorij.uni-lj.si/Dokument.php?lang=slv&id=215318 Fakulteta za strojništvo 0 0 0