TY  - JOUR
AU  - Stević, Zoran
AU  - Dimitrijević, Stevan P.
AU  - Stević, Miša
AU  - Stolić, Predrag
AU  - Petrović, Sanja J.
AU  - Radivojević, Milan
AU  - Radovanović, Ilija
PY  - 2023
UR  - http://TechnoRep.tmf.bg.ac.rs/handle/123456789/7468
AB  - This paper presents the development of a piece of induction hardening equipment based on the foundations of the design, starting from zero. It was intended for steels in general, and was tested on unalloyed low- and medium-carbon steels, whereas the results for EN 1C60 steel are shown in this study. The EN 1C60 steel showed average results, and was chosen as a representative of a wider group of engineering steels. The main objective of this work was to develop a flexible system for mild steel hardening that can be used for various hardening depths and steel types. The system design’s priorities were the use of standard electronic components to avoid supply chain disruptions and to achieve high energy efficiency. The construction of the prototype in full detail is also presented. The optimal process parameters are listed, as well as the procedure of their obtaining by using the appropriate simulation method. The key parameters were adjusted in consecutive steps. This study resulted in high matching between the model predictions and experimental results. The basic goal of this research was achieved, with the system having a minimum energy efficiency of 75.3%, a most frequent energy efficiency of 90% and a maximum energy efficiency of 95.1%.
PB  - MDPI
T2  - Applied Sciences
T1  - The Design of a System for the Induction Hardening of Steels Using Simulation Parameters
IS  - 20
SP  - 11432
VL  - 13
DO  - 10.3390/app132011432
ER  - 

@article{
author = "Stević, Zoran and Dimitrijević, Stevan P. and Stević, Miša and Stolić, Predrag and Petrović, Sanja J. and Radivojević, Milan and Radovanović, Ilija",
year = "2023",
abstract = "This paper presents the development of a piece of induction hardening equipment based on the foundations of the design, starting from zero. It was intended for steels in general, and was tested on unalloyed low- and medium-carbon steels, whereas the results for EN 1C60 steel are shown in this study. The EN 1C60 steel showed average results, and was chosen as a representative of a wider group of engineering steels. The main objective of this work was to develop a flexible system for mild steel hardening that can be used for various hardening depths and steel types. The system design’s priorities were the use of standard electronic components to avoid supply chain disruptions and to achieve high energy efficiency. The construction of the prototype in full detail is also presented. The optimal process parameters are listed, as well as the procedure of their obtaining by using the appropriate simulation method. The key parameters were adjusted in consecutive steps. This study resulted in high matching between the model predictions and experimental results. The basic goal of this research was achieved, with the system having a minimum energy efficiency of 75.3%, a most frequent energy efficiency of 90% and a maximum energy efficiency of 95.1%.",
publisher = "MDPI",
journal = "Applied Sciences",
title = "The Design of a System for the Induction Hardening of Steels Using Simulation Parameters",
number = "20",
pages = "11432",
volume = "13",
doi = "10.3390/app132011432"
}

Stević, Z., Dimitrijević, S. P., Stević, M., Stolić, P., Petrović, S. J., Radivojević, M.,& Radovanović, I.. (2023). The Design of a System for the Induction Hardening of Steels Using Simulation Parameters. in Applied Sciences
MDPI., 13(20), 11432.
https://doi.org/10.3390/app132011432

Stević Z, Dimitrijević SP, Stević M, Stolić P, Petrović SJ, Radivojević M, Radovanović I. The Design of a System for the Induction Hardening of Steels Using Simulation Parameters. in Applied Sciences. 2023;13(20):11432.
doi:10.3390/app132011432 .

Stević, Zoran, Dimitrijević, Stevan P., Stević, Miša, Stolić, Predrag, Petrović, Sanja J., Radivojević, Milan, Radovanović, Ilija, "The Design of a System for the Induction Hardening of Steels Using Simulation Parameters" in Applied Sciences, 13, no. 20 (2023):11432,
https://doi.org/10.3390/app132011432 . .

TY  - JOUR
AU  - Petrović, Sanja J.
AU  - Bogdanović, Grozdanka D.
AU  - Antonijević, Milan M.
AU  - Vukčević, Marija
AU  - Kovačević, Renata
PY  - 2023
UR  - http://TechnoRep.tmf.bg.ac.rs/handle/123456789/6989
AB  - Research on chalcopyrite leaching represents a great challenge, given its importance as one of the most abundant copper minerals and its significant role in global copper extraction. This study aimed to evaluate the effects of different parameters on chalcopyrite leaching by hydrogen peroxide as a strong oxidizing reagent in sulfuric acid solution. A series of leaching tests were carried out to investigate the effect of the solid/liquid ratio, stirring speed, temperature, oxidant and acid concentrations, and lixiviant dosing method on copper extraction from chalcopyrite concentrate. The catalytic decomposition of hydrogen peroxide occurred in the investigated leaching system, as reflected in the obtained metal extraction values. Copper extraction was increased in the first 60 min of the reaction, after which it essentially ceased. The maximum final copper extraction of 64.5% was attained with 3.0 mol/L H2O2 in 3.0 mol/L H2SO4 at a temperature of 40 °C after 120 min of reaction. Due to the catalytic decomposition of hydrogen peroxide in the examined leaching system, the leaching experiment was performed with the periodic addition of lixiviant at specific time intervals as well. The dissolution process was described by the first-order kinetics equation with an apparent activation energy of ~39 kJ/mol. Finally, XRD and SEM-EDS analyses were used to characterize the leached residue, and the results showed that the formation of elemental sulfur on the chalcopyrite surface affected the dissolution process.
PB  - MDPI
T2  - Metals
T1  - The Extraction of Copper from Chalcopyrite Concentrate with Hydrogen Peroxide in Sulfuric Acid Solution
IS  - 11
SP  - 1818
VL  - 13
DO  - 10.3390/met13111818
ER  - 

@article{
author = "Petrović, Sanja J. and Bogdanović, Grozdanka D. and Antonijević, Milan M. and Vukčević, Marija and Kovačević, Renata",
year = "2023",
abstract = "Research on chalcopyrite leaching represents a great challenge, given its importance as one of the most abundant copper minerals and its significant role in global copper extraction. This study aimed to evaluate the effects of different parameters on chalcopyrite leaching by hydrogen peroxide as a strong oxidizing reagent in sulfuric acid solution. A series of leaching tests were carried out to investigate the effect of the solid/liquid ratio, stirring speed, temperature, oxidant and acid concentrations, and lixiviant dosing method on copper extraction from chalcopyrite concentrate. The catalytic decomposition of hydrogen peroxide occurred in the investigated leaching system, as reflected in the obtained metal extraction values. Copper extraction was increased in the first 60 min of the reaction, after which it essentially ceased. The maximum final copper extraction of 64.5% was attained with 3.0 mol/L H2O2 in 3.0 mol/L H2SO4 at a temperature of 40 °C after 120 min of reaction. Due to the catalytic decomposition of hydrogen peroxide in the examined leaching system, the leaching experiment was performed with the periodic addition of lixiviant at specific time intervals as well. The dissolution process was described by the first-order kinetics equation with an apparent activation energy of ~39 kJ/mol. Finally, XRD and SEM-EDS analyses were used to characterize the leached residue, and the results showed that the formation of elemental sulfur on the chalcopyrite surface affected the dissolution process.",
publisher = "MDPI",
journal = "Metals",
title = "The Extraction of Copper from Chalcopyrite Concentrate with Hydrogen Peroxide in Sulfuric Acid Solution",
number = "11",
pages = "1818",
volume = "13",
doi = "10.3390/met13111818"
}

Petrović, S. J., Bogdanović, G. D., Antonijević, M. M., Vukčević, M.,& Kovačević, R.. (2023). The Extraction of Copper from Chalcopyrite Concentrate with Hydrogen Peroxide in Sulfuric Acid Solution. in Metals
MDPI., 13(11), 1818.
https://doi.org/10.3390/met13111818

Petrović SJ, Bogdanović GD, Antonijević MM, Vukčević M, Kovačević R. The Extraction of Copper from Chalcopyrite Concentrate with Hydrogen Peroxide in Sulfuric Acid Solution. in Metals. 2023;13(11):1818.
doi:10.3390/met13111818 .

Petrović, Sanja J., Bogdanović, Grozdanka D., Antonijević, Milan M., Vukčević, Marija, Kovačević, Renata, "The Extraction of Copper from Chalcopyrite Concentrate with Hydrogen Peroxide in Sulfuric Acid Solution" in Metals, 13, no. 11 (2023):1818,
https://doi.org/10.3390/met13111818 . .

Stević, Z., Dimitrijević, S., Dimitrijević, S.,& Lekovski, S.. (2021). Razvoј hardvera i softvera za energetski efikasne računarom vođene peći za sinterovanje. in Tehnički fakultet u Boru, Univerzitet u Beogradu
Univerzitet u Beogradu, Tehnički fakultet u Boru..
https://hdl.handle.net/21.15107/rcub_technorep_6757

Stević Z, Dimitrijević S, Dimitrijević S, Lekovski S. Razvoј hardvera i softvera za energetski efikasne računarom vođene peći za sinterovanje. in Tehnički fakultet u Boru, Univerzitet u Beogradu. 2021;.
https://hdl.handle.net/21.15107/rcub_technorep_6757 .

Stević, Zoran, Dimitrijević, Stevan, Dimitrijević, Silvana, Lekovski, Sande, "Razvoј hardvera i softvera za energetski efikasne računarom vođene peći za sinterovanje" in Tehnički fakultet u Boru, Univerzitet u Beogradu (2021),
https://hdl.handle.net/21.15107/rcub_technorep_6757 .