11. Effect of double-step and strain-assisted tempering on properties of medium-carbon steelPavel Salvetr, Andrea Školáková, Jakub Kotous, J. Drahokoupil, Daniel Melzer, Zdeňek Jansa, Črtomir Donik, Aleksandr Gokhman, Zbyšek Nový, 2023, original scientific article Keywords: medium-carbon steel, tempering, strengthening, mechanical properties, microstructure Published in DiRROS: 02.02.2024; Views: 158; Downloads: 77 Full text (9,82 MB) This document has many files! More... |
12. Effect of Cu alloying on mechanical properties of medium-c steel after long-time tempering at 500 °CPavel Salvetr, Aleksandr Gokhman, Milan Svoboda, Črtomir Donik, Ivana Podstranská, Jakub Kotous, Zbyšek Nový, 2023, original scientific article Keywords: long-time tempering, strengthening, Cu precipitate, medium-C steel, mechanical properties Published in DiRROS: 02.02.2024; Views: 202; Downloads: 75 Full text (6,20 MB) This document has many files! More... |
13. Mechanical properties of high carbon low-density steelsJiri Hajek, Zbyšek Nový, Ludmila Kucerova, Hana Jirková, Črtomir Donik, Zdeňek Jansa, 2023, original scientific article Keywords: low density steels, heat treatment, tensile test Published in DiRROS: 02.02.2024; Views: 136; Downloads: 72 Full text (10,85 MB) This document has many files! More... |
14. Solidification behavior of Fe-6.5Si alloy powder for AM-SLM processing, as assessed by differential scanning calorimetryDarja Steiner Petrovič, Črtomir Donik, Irena Paulin, Matjaž Godec, Maja Vončina, Martin Petrun, 2023, original scientific article Keywords: soft magnetic alloy, differential scanning calorimetry, oxygen, high-temperature phase, microstructure, eutectics Published in DiRROS: 02.02.2024; Views: 147; Downloads: 68 Full text (9,05 MB) This document has many files! More... |
15. Aspects of bending high-borated austenitic stainless steel sheets for interim storage of spent nuclear fuelJosef Odehnal, Tomáš Studecký, Petra Čejková, Ivana Poláková, Martin Rund, Václav Bruná, Petr Martinek, Pavel Francisko, Črtomir Donik, 2023, original scientific article Keywords: interim storage, spent fuel, borated stainless steel, cold working, bending Published in DiRROS: 01.02.2024; Views: 142; Downloads: 66 Full text (10,05 MB) This document has many files! More... |
16. Effects of variated final temperature and workpiece thickness for hot rolling of aluminum alloy EN AW-8011Jakob Kraner, Peter Cvahte, Primož Šuštarič, Tomaž Šuštar, Črtomir Donik, Irena Paulin, Shae K. Kim, Kjung Il Kim, 2023, original scientific article Keywords: aluminum alloy, hot rolling, simulations, metallography, mechanical properties Published in DiRROS: 01.02.2024; Views: 144; Downloads: 78 Full text (5,46 MB) This document has many files! More... |
17. Improving the surface properties of additive-manufactured Inconel 625 by plasma nitridingDanijela Anica Skobir Balantič, Črtomir Donik, Bojan Podgornik, Aleksandra Kocijan, Matjaž Godec, 2023, original scientific article Abstract: As a surface-hardening technique, plasma nitriding is a common procedure for improving the properties of
conventional Ni-based alloys. The diffusion of nitrogen hardens a layer on the surface of the alloy, leading to
better wear resistance and a higher coefficient of friction, as well as a higher surface hardness. This study reports
the effect of plasma nitriding on additive-manufactured (AM) Inconel 625 (IN625) compared to its conventional
manufactured and nitrided counterparts. The samples produced with the laser powder-bed fusion (LPBF) process
were subsequently plasma nitrided in the as-built condition, stress-relief annealed at 870 °C and solution treated
at 1050 °C. The plasma nitridings were carried out at 430 °C and 500 °C for 15 h. The growth kinetics of the
nitride layer of the AM samples depends on the prior heat treatments and is faster in the as-built state due to the
specific cellular structure. The lower nitriding temperature leads to the formation of expanded austenite in the
nitride layer, while at the higher nitriding temperature, the expanded austenite decomposes and CrN precipitation
occurs. The XRD and SEM analyses confirmed the presence of two layers: the surface layer and the
diffusion layer beneath. The lower nitriding temperature caused the formation of expanded austenite or a
combination of expanded austenite and CrN. The higher nitriding temperature led to the decomposition of the
expanded austenite and to the formation/precipitation of CrN. The higher nitriding temperature also decreased
the corrosion resistance slightly due to the increased number of precipitated Cr-nitrides. On the other hand, the
wear resistance was significantly improved after plasma nitriding and was much less influenced by the nitriding
temperature. Keywords: additive manufacturing, powder-bed fusion, plasma nitriding, expanded austenite, wear and corrosion resistance, Ni-based alloy Published in DiRROS: 31.01.2024; Views: 183; Downloads: 79 Full text (7,98 MB) This document has many files! More... |
18. The influence of the plasma-nitriding temperature on the microstructure evolution and surface properties of additive-manufactured 18Ni300 maraging steelMatjaž Godec, Francisco Ruiz-Zepeda, Bojan Podgornik, Črtomir Donik, Aleksandra Kocijan, Danijela Anica Skobir Balantič, 2022, original scientific article Keywords: maraging steel, powder bed fusion, plasma nitriding, microstructure, wear resistance, corrosion resistance Published in DiRROS: 06.05.2022; Views: 587; Downloads: 205 Full text (6,68 MB) This document has many files! More... |