TY  - GEN
AU  - Mihailović, Marija
AU  - Jegdić, Bore
AU  - Jugović, Branimir
AU  - Kovačina, Jovanka
AU  - Radojković, Bojana
AU  - Patarić, Aleksandra
AU  - Jokić, Bojan
PY  - 2021
UR  - https://dais.sanu.ac.rs/123456789/11630
AB  - Praćenje pojave i brzine korozije, nastanak termičkih oksida na površini metalnih delova eletroenergetskog postrojenјa, kao i način njihovog otklanjanja na način koji je tehnološki pogodan, ekonomski pristupačan i ekološki opravdan prikazan je u ovom tehničkom rešenju Ispitivanjem je ustanovljeno da su metalni delovi na kojima se javlja korozija izrađeni od na nerđajućeg čelika AISI 304, pa je pojava korozije i termičkih oksida praćena je u odnosu na to, kao i sastav prašine sa kojom su metalni delovi u kontaktu. Pojava termičkih oksida na površini nerđajućih čelika posledica je povišene temperature na mestu zavarivanja metalnih delova.
Merena je vrednost pH oba rastvora: etalonskog i zasićenog rastvoru prašine iz pogona.
Sastav uzoraka prašine određen je FTIR metodom, pa su na osnovu prisutnih jona u rastvoru definisana ostala ispitivanja.
Određivan je korozioni potencijal Ekor, vrednost otpora polarizacije Rp, kao i gustina struje korozije jkor. Sva ispitivanja nerđajućeg čelika u etalonskom rastvoru i u zasićenom rastvoru prašine iz pogona firme naručioca, rađena su za 1 sat i u toku 25 dana.
Kao rezultat svih istražoivanja, date su tehnološke preporuke i način otklanjanja korozije i termičkih oksida.
Rešenje je prodato naručuicu u toku 2020.godine, a od januara 2021.godine primenjeno u postrojenju naručioca, ELNOS BL d.o.o., koji su izjavom potvrdili primenu ovog tehničkog rešenja u svom poslovanju.
AB  - Monitoring the occurrence and rate of corrosion, the formation of thermal oxides on the surface of metal parts of the power plant, as well as the method of their elimination in a way that is technologically suitable, economically affordable and environmentally justified is shown in this technical solution. It has been established that the metal elements affected by corrosion were made from stainless steel AISI 304. Accordingly, the occurrence of corrosion and thermal oxides was monitored based on the material and the composition of the dust with which the metal parts are in contact. The emergence of thermal oxides on the surface of stainless steels is a consequence of the elevated temperature at the welding site.
The pH value of both solutions was measured: standard and saturated solution of dust from the plant. The composition of the dust samples was determined by FTIR. The other tests were defined based on the ions present in the solution.
The corrosion potential, the value of the polarization resistance, as well as the corrosion current density were determined. All tests of stainless steel in the standard solution and in the saturated solution of dust were performed for one hour within a span of 25 days.
Technological recommendations on how to eliminate corrosion and thermal oxides are provided.
The solution has been applied since January 2021 by ELNOS BL d.o.o.
PB  - Belgrade : University of Belgrade - Institute of Chemistry, Technology and Metallurgy
T1  - Ispitivanje i otklanјanјe pojave korozije i termičkih oksida na metalnim delovima elektroenergetskog postojenja
T1  - Possibility of removal of corrosion and thermal oxides on metal parts of electric power plant
UR  - https://hdl.handle.net/21.15107/rcub_dais_11630
ER  - 

@misc{
author = "Mihailović, Marija and Jegdić, Bore and Jugović, Branimir and Kovačina, Jovanka and Radojković, Bojana and Patarić, Aleksandra and Jokić, Bojan",
year = "2021",
abstract = "Praćenje pojave i brzine korozije, nastanak termičkih oksida na površini metalnih delova eletroenergetskog postrojenјa, kao i način njihovog otklanjanja na način koji je tehnološki pogodan, ekonomski pristupačan i ekološki opravdan prikazan je u ovom tehničkom rešenju Ispitivanjem je ustanovljeno da su metalni delovi na kojima se javlja korozija izrađeni od na nerđajućeg čelika AISI 304, pa je pojava korozije i termičkih oksida praćena je u odnosu na to, kao i sastav prašine sa kojom su metalni delovi u kontaktu. Pojava termičkih oksida na površini nerđajućih čelika posledica je povišene temperature na mestu zavarivanja metalnih delova.
Merena je vrednost pH oba rastvora: etalonskog i zasićenog rastvoru prašine iz pogona.
Sastav uzoraka prašine određen je FTIR metodom, pa su na osnovu prisutnih jona u rastvoru definisana ostala ispitivanja.
Određivan je korozioni potencijal Ekor, vrednost otpora polarizacije Rp, kao i gustina struje korozije jkor. Sva ispitivanja nerđajućeg čelika u etalonskom rastvoru i u zasićenom rastvoru prašine iz pogona firme naručioca, rađena su za 1 sat i u toku 25 dana.
Kao rezultat svih istražoivanja, date su tehnološke preporuke i način otklanjanja korozije i termičkih oksida.
Rešenje je prodato naručuicu u toku 2020.godine, a od januara 2021.godine primenjeno u postrojenju naručioca, ELNOS BL d.o.o., koji su izjavom potvrdili primenu ovog tehničkog rešenja u svom poslovanju., Monitoring the occurrence and rate of corrosion, the formation of thermal oxides on the surface of metal parts of the power plant, as well as the method of their elimination in a way that is technologically suitable, economically affordable and environmentally justified is shown in this technical solution. It has been established that the metal elements affected by corrosion were made from stainless steel AISI 304. Accordingly, the occurrence of corrosion and thermal oxides was monitored based on the material and the composition of the dust with which the metal parts are in contact. The emergence of thermal oxides on the surface of stainless steels is a consequence of the elevated temperature at the welding site.
The pH value of both solutions was measured: standard and saturated solution of dust from the plant. The composition of the dust samples was determined by FTIR. The other tests were defined based on the ions present in the solution.
The corrosion potential, the value of the polarization resistance, as well as the corrosion current density were determined. All tests of stainless steel in the standard solution and in the saturated solution of dust were performed for one hour within a span of 25 days.
Technological recommendations on how to eliminate corrosion and thermal oxides are provided.
The solution has been applied since January 2021 by ELNOS BL d.o.o.",
publisher = "Belgrade : University of Belgrade - Institute of Chemistry, Technology and Metallurgy",
title = "Ispitivanje i otklanјanјe pojave korozije i termičkih oksida na metalnim delovima elektroenergetskog postojenja, Possibility of removal of corrosion and thermal oxides on metal parts of electric power plant",
url = "https://hdl.handle.net/21.15107/rcub_dais_11630"
}

Mihailović, M., Jegdić, B., Jugović, B., Kovačina, J., Radojković, B., Patarić, A.,& Jokić, B.. (2021). Ispitivanje i otklanјanјe pojave korozije i termičkih oksida na metalnim delovima elektroenergetskog postojenja. 
Belgrade : University of Belgrade - Institute of Chemistry, Technology and Metallurgy..
https://hdl.handle.net/21.15107/rcub_dais_11630

Mihailović M, Jegdić B, Jugović B, Kovačina J, Radojković B, Patarić A, Jokić B. Ispitivanje i otklanјanјe pojave korozije i termičkih oksida na metalnim delovima elektroenergetskog postojenja. 2021;.
https://hdl.handle.net/21.15107/rcub_dais_11630 .

Mihailović, Marija, Jegdić, Bore, Jugović, Branimir, Kovačina, Jovanka, Radojković, Bojana, Patarić, Aleksandra, Jokić, Bojan, "Ispitivanje i otklanјanјe pojave korozije i termičkih oksida na metalnim delovima elektroenergetskog postojenja" (2021),
https://hdl.handle.net/21.15107/rcub_dais_11630 .

TY  - CONF
AU  - Đorđević, Nataša
AU  - Obradović, Nina
AU  - Sokić, Miroslav D.
AU  - Marković, Branislav R.
AU  - Patarić, Aleksandra
AU  - Petronijević, Nela
PY  - 2019
UR  - https://dais.sanu.ac.rs/123456789/14867
AB  - Mechanochemical activation of 2MgO•2Al2O3•5SiO2, starting components of cordierite, was used in aim to decrease the sintering temperature. Cordierite is very attractive ceramic material due to its properties, excellent thermal shock resistance, low dielectric constants (~5) and low thermal expansions (20•10-7 ºC-1). Specific surface area of the activated components was detected by the BET method. TG and DTA methods have followed behaviors of the three-component system. To see the influence of relaxation time on the activated components, FT IR has analyzed the starting components as well as activated mixture after 24h and 24 months. TG analyses of starting cordierite mixture activated 5 to 240 minutes showed a mass decrease from 8 to12%. DT analyses showed the influence of mechanochemical activation of the starting components as increasing energy of the starting cordierite mixture, which resulted in moving the endothermic and exothermic effects to lower temperatures. The increasing of the temperatures of these effects was about 100°C, depending on activation time. IR analyses showed that relaxation time, that is laying-off time to the moment of sintering, do not influence changes of activated mixtures. Since the given results, it can be concluded that the activated sample has no changes to the moment of using for a certain purpose (sintering) for any time since activation.
PB  - Belgrade : Association of Metallurgical Engineers of Serbia (AMES)
C3  - Book of Abstracts / Metallurgical & Materials Engineering Congress of South-East Europe (MME SEE 2019), June 5-7, 2019, Belgrade, Serbia
T1  - Activation and relaxation time influence on cordierite ceramics
SP  - 61
EP  - 61
UR  - https://hdl.handle.net/21.15107/rcub_dais_14867
ER  - 

@conference{
author = "Đorđević, Nataša and Obradović, Nina and Sokić, Miroslav D. and Marković, Branislav R. and Patarić, Aleksandra and Petronijević, Nela",
year = "2019",
abstract = "Mechanochemical activation of 2MgO•2Al2O3•5SiO2, starting components of cordierite, was used in aim to decrease the sintering temperature. Cordierite is very attractive ceramic material due to its properties, excellent thermal shock resistance, low dielectric constants (~5) and low thermal expansions (20•10-7 ºC-1). Specific surface area of the activated components was detected by the BET method. TG and DTA methods have followed behaviors of the three-component system. To see the influence of relaxation time on the activated components, FT IR has analyzed the starting components as well as activated mixture after 24h and 24 months. TG analyses of starting cordierite mixture activated 5 to 240 minutes showed a mass decrease from 8 to12%. DT analyses showed the influence of mechanochemical activation of the starting components as increasing energy of the starting cordierite mixture, which resulted in moving the endothermic and exothermic effects to lower temperatures. The increasing of the temperatures of these effects was about 100°C, depending on activation time. IR analyses showed that relaxation time, that is laying-off time to the moment of sintering, do not influence changes of activated mixtures. Since the given results, it can be concluded that the activated sample has no changes to the moment of using for a certain purpose (sintering) for any time since activation.",
publisher = "Belgrade : Association of Metallurgical Engineers of Serbia (AMES)",
journal = "Book of Abstracts / Metallurgical & Materials Engineering Congress of South-East Europe (MME SEE 2019), June 5-7, 2019, Belgrade, Serbia",
title = "Activation and relaxation time influence on cordierite ceramics",
pages = "61-61",
url = "https://hdl.handle.net/21.15107/rcub_dais_14867"
}

Đorđević, N., Obradović, N., Sokić, M. D., Marković, B. R., Patarić, A.,& Petronijević, N.. (2019). Activation and relaxation time influence on cordierite ceramics. in Book of Abstracts / Metallurgical & Materials Engineering Congress of South-East Europe (MME SEE 2019), June 5-7, 2019, Belgrade, Serbia
Belgrade : Association of Metallurgical Engineers of Serbia (AMES)., 61-61.
https://hdl.handle.net/21.15107/rcub_dais_14867

Đorđević N, Obradović N, Sokić MD, Marković BR, Patarić A, Petronijević N. Activation and relaxation time influence on cordierite ceramics. in Book of Abstracts / Metallurgical & Materials Engineering Congress of South-East Europe (MME SEE 2019), June 5-7, 2019, Belgrade, Serbia. 2019;:61-61.
https://hdl.handle.net/21.15107/rcub_dais_14867 .

Đorđević, Nataša, Obradović, Nina, Sokić, Miroslav D., Marković, Branislav R., Patarić, Aleksandra, Petronijević, Nela, "Activation and relaxation time influence on cordierite ceramics" in Book of Abstracts / Metallurgical & Materials Engineering Congress of South-East Europe (MME SEE 2019), June 5-7, 2019, Belgrade, Serbia (2019):61-61,
https://hdl.handle.net/21.15107/rcub_dais_14867 .

TY  - CONF
AU  - Đorđević, Nataša
AU  - Obradović, Nina
AU  - Sokić, Miroslav D.
AU  - Marković, Branislav
AU  - Patarić, Aleksandra
AU  - Petronijević, Nela
PY  - 2019
UR  - https://dais.sanu.ac.rs/123456789/14866
AB  - The influence of Bi2O3 as a functional additive on the process of obtaining cordierite, 2MgO-2Al2O3-5SiO2 (MAS) was studied by sintering the MgO / Bi2O3 system (sintered at 820 °C and 1100 °C), Al2O3 / Bi2O3 and SiO2 / Bi2O3 (sintered at 1100 °C ), the composition being 80% oxide and 20% Bi2O3. The effects of sintering, composition, and morphology were followed by X-ray diffraction, scanning electron microscopy and EDS analysis. It has been found that, in addition to the liquid phase, Bi2O3 produces intermediate metastable compounds with MgO and Al2O3. The sintering of MAS ceramics with 10% Bi2O3 at 1000 °C, 1100 °C and 1200 °C was also performed. Binary systems MgO / Bi2O3 at 820 ºC and 1100 ºC, Al2O3 / Bi2O3 and SiO2 / Bi2O3 were sintered at 1100 ºC, as well as MgO, Al2O3, SiO2 / Bi2O3 at 1000 ºC, 1100 ºC and 1200 ºC to examine the reaction of the cordierite synthesis. The results show the formation of a liquid phase at 820 °C (melting temperature Bi2O3), as well as the formation of metastable compounds forming MgO and Al2O3 with Bi2O3 at 1100 °C and which diffuse through the liquid phase, thus enabling the mechanism of reaction in the multi-component system to be accelerated from two aspects. By the sintering of a three-component MAS system in the presence of Bi2O3, the existence of cordierite was established. The lowest temperature at which the tracer cordierite was observed (in hexagonal form - indialite) is 1100 °C, while in the sintered system at 1200 ºC the most frequent phase is indialite. This study found that the presence of Bi2O3 in basic cordierite mixture allows the sintering temperature to decrease by ~ 170 ºC relative to the temperature of the formation of cordierite ceramics from the mixture without the presence of functional additives.
PB  - Belgrade : Association of Metallurgical Engineers of Serbia (AMES)
C3  - Book of Abstracts / Metallurgical & Materials Engineering Congress of South-East Europe (MME SEE 2019), June 5-7, 2019, Belgrade, Serbia
T1  - Bi2O3 influence on electronic ceramics sintering process and final properties
SP  - 60
EP  - 60
UR  - https://hdl.handle.net/21.15107/rcub_dais_14866
ER  - 

@conference{
author = "Đorđević, Nataša and Obradović, Nina and Sokić, Miroslav D. and Marković, Branislav and Patarić, Aleksandra and Petronijević, Nela",
year = "2019",
abstract = "The influence of Bi2O3 as a functional additive on the process of obtaining cordierite, 2MgO-2Al2O3-5SiO2 (MAS) was studied by sintering the MgO / Bi2O3 system (sintered at 820 °C and 1100 °C), Al2O3 / Bi2O3 and SiO2 / Bi2O3 (sintered at 1100 °C ), the composition being 80% oxide and 20% Bi2O3. The effects of sintering, composition, and morphology were followed by X-ray diffraction, scanning electron microscopy and EDS analysis. It has been found that, in addition to the liquid phase, Bi2O3 produces intermediate metastable compounds with MgO and Al2O3. The sintering of MAS ceramics with 10% Bi2O3 at 1000 °C, 1100 °C and 1200 °C was also performed. Binary systems MgO / Bi2O3 at 820 ºC and 1100 ºC, Al2O3 / Bi2O3 and SiO2 / Bi2O3 were sintered at 1100 ºC, as well as MgO, Al2O3, SiO2 / Bi2O3 at 1000 ºC, 1100 ºC and 1200 ºC to examine the reaction of the cordierite synthesis. The results show the formation of a liquid phase at 820 °C (melting temperature Bi2O3), as well as the formation of metastable compounds forming MgO and Al2O3 with Bi2O3 at 1100 °C and which diffuse through the liquid phase, thus enabling the mechanism of reaction in the multi-component system to be accelerated from two aspects. By the sintering of a three-component MAS system in the presence of Bi2O3, the existence of cordierite was established. The lowest temperature at which the tracer cordierite was observed (in hexagonal form - indialite) is 1100 °C, while in the sintered system at 1200 ºC the most frequent phase is indialite. This study found that the presence of Bi2O3 in basic cordierite mixture allows the sintering temperature to decrease by ~ 170 ºC relative to the temperature of the formation of cordierite ceramics from the mixture without the presence of functional additives.",
publisher = "Belgrade : Association of Metallurgical Engineers of Serbia (AMES)",
journal = "Book of Abstracts / Metallurgical & Materials Engineering Congress of South-East Europe (MME SEE 2019), June 5-7, 2019, Belgrade, Serbia",
title = "Bi2O3 influence on electronic ceramics sintering process and final properties",
pages = "60-60",
url = "https://hdl.handle.net/21.15107/rcub_dais_14866"
}

Đorđević, N., Obradović, N., Sokić, M. D., Marković, B., Patarić, A.,& Petronijević, N.. (2019). Bi2O3 influence on electronic ceramics sintering process and final properties. in Book of Abstracts / Metallurgical & Materials Engineering Congress of South-East Europe (MME SEE 2019), June 5-7, 2019, Belgrade, Serbia
Belgrade : Association of Metallurgical Engineers of Serbia (AMES)., 60-60.
https://hdl.handle.net/21.15107/rcub_dais_14866

Đorđević N, Obradović N, Sokić MD, Marković B, Patarić A, Petronijević N. Bi2O3 influence on electronic ceramics sintering process and final properties. in Book of Abstracts / Metallurgical & Materials Engineering Congress of South-East Europe (MME SEE 2019), June 5-7, 2019, Belgrade, Serbia. 2019;:60-60.
https://hdl.handle.net/21.15107/rcub_dais_14866 .

Đorđević, Nataša, Obradović, Nina, Sokić, Miroslav D., Marković, Branislav, Patarić, Aleksandra, Petronijević, Nela, "Bi2O3 influence on electronic ceramics sintering process and final properties" in Book of Abstracts / Metallurgical & Materials Engineering Congress of South-East Europe (MME SEE 2019), June 5-7, 2019, Belgrade, Serbia (2019):60-60,
https://hdl.handle.net/21.15107/rcub_dais_14866 .