Kojović, Aleksandar

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  • Kojović, Aleksandar (2)
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Author's Bibliography

Indentation behaviour of 'soft film on hard substrate' composite system type

Lamovec, Jelena; Jović, Vesna; Mladenović, Ivana; Stojanović, Dušica; Kojović, Aleksandar; Radojević, Vesna

(Belgrade, Serbia : Engineering Society for Corrosion, 2015)

TY  - JOUR
AU  - Lamovec, Jelena
AU  - Jović, Vesna
AU  - Mladenović, Ivana
AU  - Stojanović, Dušica
AU  - Kojović, Aleksandar
AU  - Radojević, Vesna
PY  - 2015
UR  - https://cer.ihtm.bg.ac.rs/handle/123456789/1689
AB  - This investigation has been carried out in order to analyse and compare the hardness response of different composite systems of the same type, named 'soft film on hard substrate' composite system. Composite systems of mono- and multilayered electrodeposited Ni and Cu thin films on (100) and (111)-oriented monocrystalline Si wafers and 100 µm-thick electrodeposited Ni film as the substrates were fabricated. The indentation behaviour of these composite structures was characterized using Berkovich nanohardness and Vickers microhardness testing. The measured hardness is so-called 'composite hardness', because the substrate participates in the plastic deformation during the indentation process. The contribution of the substrate to the measured hardness starts at indentation depths of the order of 0.07- 0.2 times the film thickness. Dependence of nanohardness and microhardness values on electrodeposition process conditions, substrate and film microstructure, total film thickness, layer thickness and Ni/Cu layer thickness ratio for different composite systems ratio was investigated. Composite hardness model of Chicot-Lesage (C-L) was chosen and applied to experimental data in order to determine absolute film hardness.
AB  - Ovo istraživanje je izvršeno u cilju analize i upoređivanja odziva različitih kompozitnih sistema koji pripadaju istom tipu sistema nazvanom 'mek film na tvrdom supstratu', pri merenju tvrdoće. Formirani su kompozitni sistemi elektrodepozicijom jedno- i višeslojnih Ni i Cu tankih filmova na (100) i (111)- orijentisanim monokristalnim Si pločicama i 100-µm debelom elektrodeponovanom Ni filmu kao supstratima. Ponašanje ovih kompozitnih struktura pri utiskivanju je okarakterisano merenjem nanotvrdoće po Berkoviču i mikrotvrdoće po Vikersu. Izmerena vrednost mikrotvrdoće se naziva 'kompozitnom tvrdoćom' jer prilikom testiranja utiskivanjem dolazi i do plastične deformacije supstrata. Doprinos deformacije supstrata izmerenoj tvrdoći počinje na dubinama utiskivanja koje su reda 0.07-0.2 puta manje od debljine filma. Istraživana je zavisnost vrednosti nanotvrdoće i mikrotvrdoće od procesnih parametera elektrodepozicije, mikrostrukture supstrata i filmova, ukupne debljine filma, debljine pojedinačnog sloja u filmu i odnosa debljina Ni/Cu pojedinačnih slojeva u filmu za različite kompozitne sisteme. Radi određivanja apsolutne tvrdoće filma u sistemu, odabran je i na eksperimentalne rezultate primenjen model kompozitne tvrdoće Šiko-Lezaž (C-L).
PB  - Belgrade, Serbia : Engineering Society for Corrosion
T2  - Zaštita materijala
T1  - Indentation behaviour of 'soft film on hard substrate' composite system type
T1  - Ponašanje kompozitnih sistema tipa 'mek film na tvrdom supstratu' na testu utiskivanja
VL  - 56
IS  - 3
SP  - 269
EP  - 277
DO  - 10.5937/ZasMat1503269L
ER  - 
@article{
author = "Lamovec, Jelena and Jović, Vesna and Mladenović, Ivana and Stojanović, Dušica and Kojović, Aleksandar and Radojević, Vesna",
year = "2015",
abstract = "This investigation has been carried out in order to analyse and compare the hardness response of different composite systems of the same type, named 'soft film on hard substrate' composite system. Composite systems of mono- and multilayered electrodeposited Ni and Cu thin films on (100) and (111)-oriented monocrystalline Si wafers and 100 µm-thick electrodeposited Ni film as the substrates were fabricated. The indentation behaviour of these composite structures was characterized using Berkovich nanohardness and Vickers microhardness testing. The measured hardness is so-called 'composite hardness', because the substrate participates in the plastic deformation during the indentation process. The contribution of the substrate to the measured hardness starts at indentation depths of the order of 0.07- 0.2 times the film thickness. Dependence of nanohardness and microhardness values on electrodeposition process conditions, substrate and film microstructure, total film thickness, layer thickness and Ni/Cu layer thickness ratio for different composite systems ratio was investigated. Composite hardness model of Chicot-Lesage (C-L) was chosen and applied to experimental data in order to determine absolute film hardness., Ovo istraživanje je izvršeno u cilju analize i upoređivanja odziva različitih kompozitnih sistema koji pripadaju istom tipu sistema nazvanom 'mek film na tvrdom supstratu', pri merenju tvrdoće. Formirani su kompozitni sistemi elektrodepozicijom jedno- i višeslojnih Ni i Cu tankih filmova na (100) i (111)- orijentisanim monokristalnim Si pločicama i 100-µm debelom elektrodeponovanom Ni filmu kao supstratima. Ponašanje ovih kompozitnih struktura pri utiskivanju je okarakterisano merenjem nanotvrdoće po Berkoviču i mikrotvrdoće po Vikersu. Izmerena vrednost mikrotvrdoće se naziva 'kompozitnom tvrdoćom' jer prilikom testiranja utiskivanjem dolazi i do plastične deformacije supstrata. Doprinos deformacije supstrata izmerenoj tvrdoći počinje na dubinama utiskivanja koje su reda 0.07-0.2 puta manje od debljine filma. Istraživana je zavisnost vrednosti nanotvrdoće i mikrotvrdoće od procesnih parametera elektrodepozicije, mikrostrukture supstrata i filmova, ukupne debljine filma, debljine pojedinačnog sloja u filmu i odnosa debljina Ni/Cu pojedinačnih slojeva u filmu za različite kompozitne sisteme. Radi određivanja apsolutne tvrdoće filma u sistemu, odabran je i na eksperimentalne rezultate primenjen model kompozitne tvrdoće Šiko-Lezaž (C-L).",
publisher = "Belgrade, Serbia : Engineering Society for Corrosion",
journal = "Zaštita materijala",
title = "Indentation behaviour of 'soft film on hard substrate' composite system type, Ponašanje kompozitnih sistema tipa 'mek film na tvrdom supstratu' na testu utiskivanja",
volume = "56",
number = "3",
pages = "269-277",
doi = "10.5937/ZasMat1503269L"
}
Lamovec, J., Jović, V., Mladenović, I., Stojanović, D., Kojović, A.,& Radojević, V.. (2015). Indentation behaviour of 'soft film on hard substrate' composite system type. in Zaštita materijala
Belgrade, Serbia : Engineering Society for Corrosion., 56(3), 269-277.
https://doi.org/10.5937/ZasMat1503269L
Lamovec J, Jović V, Mladenović I, Stojanović D, Kojović A, Radojević V. Indentation behaviour of 'soft film on hard substrate' composite system type. in Zaštita materijala. 2015;56(3):269-277.
doi:10.5937/ZasMat1503269L .
Lamovec, Jelena, Jović, Vesna, Mladenović, Ivana, Stojanović, Dušica, Kojović, Aleksandar, Radojević, Vesna, "Indentation behaviour of 'soft film on hard substrate' composite system type" in Zaštita materijala, 56, no. 3 (2015):269-277,
https://doi.org/10.5937/ZasMat1503269L . .
2

The analysis of forming PVB-SiO2 nanocomposite fibers by the electrospinning process

Obradović, Vera; Kojović, Aleksandar; Stojanović, Dušica B.; Nikolić, Nebojša D.; Živković, Irena; Uskoković, Petar S.; Aleksić, Radoslav

(Vojnotehnički institut, Beograd, 2011)

TY  - JOUR
AU  - Obradović, Vera
AU  - Kojović, Aleksandar
AU  - Stojanović, Dušica B.
AU  - Nikolić, Nebojša D.
AU  - Živković, Irena
AU  - Uskoković, Petar S.
AU  - Aleksić, Radoslav
PY  - 2011
UR  - https://cer.ihtm.bg.ac.rs/handle/123456789/879
AB  - The poly (vinyl butyral)-silica (PVB-SiO2) nanofibers were obtained by the electrospinning process. The experiments were carried out with PVB solution in concentration of 10 wt.% where ethanol was used as the solvent. The silica nanoparticles were added in the solution in different contents of 1, 3 and 5 wt.% SiO2 and nanoparticles were modified with γ-aminopropyltriethoxysilane (AMEO silane). The impacts of the parameters of the electrospinning process and the silica nanoparticles on the produced PVB-SiO2 nanocomposite fibers were tested. The structures of the PVB-SiO2 nanocomposite fibers were investigated using optical microscopy and scanning electron microscopy (SEM). The morphology and distribution of the resulting nanofibers were analyzed using the software Image-Pro Plus. .
AB  - Poli (vinil butiral)-silika (PVB-SiO2) nanovlakna su dobijena metodom elektrospininga. Eksperimenti su izvedeni u rastvoru 10 mas.% PVB-a u etanolu koji je korišćen kao rastvarač. Nanočestice silike su dodate sa različitim sadržajem od 1, 3 i 5 mas.% SiO2 i modifikovane γ-aminopropiltrietoksi silanom (AMEO silanom). Istražen je uticaj procesnih parametara elektrospininga na nanokompozitna vlakna PVB-SiO2. Struktura PVB-SiO2 nanokompozitnih vlakana je proučavana pomoću optičke mikroskopije i skenirajuće elektronske mikroskopije (SEM). Morfologija proizvedenih nanokompozitnih vlakana i njihova raspodela je analizirana u Image Pro Plus softveru. .
PB  - Vojnotehnički institut, Beograd
T2  - Scientific Technical Review
T1  - The analysis of forming PVB-SiO2 nanocomposite fibers by the electrospinning process
T1  - Analiza formiranja PVB-SiO2 nanokompozitnih vlakana pomoću elektrospining procesa
VL  - 61
IS  - 3-4
SP  - 34
EP  - 38
UR  - https://hdl.handle.net/21.15107/rcub_cer_879
ER  - 
@article{
author = "Obradović, Vera and Kojović, Aleksandar and Stojanović, Dušica B. and Nikolić, Nebojša D. and Živković, Irena and Uskoković, Petar S. and Aleksić, Radoslav",
year = "2011",
abstract = "The poly (vinyl butyral)-silica (PVB-SiO2) nanofibers were obtained by the electrospinning process. The experiments were carried out with PVB solution in concentration of 10 wt.% where ethanol was used as the solvent. The silica nanoparticles were added in the solution in different contents of 1, 3 and 5 wt.% SiO2 and nanoparticles were modified with γ-aminopropyltriethoxysilane (AMEO silane). The impacts of the parameters of the electrospinning process and the silica nanoparticles on the produced PVB-SiO2 nanocomposite fibers were tested. The structures of the PVB-SiO2 nanocomposite fibers were investigated using optical microscopy and scanning electron microscopy (SEM). The morphology and distribution of the resulting nanofibers were analyzed using the software Image-Pro Plus. ., Poli (vinil butiral)-silika (PVB-SiO2) nanovlakna su dobijena metodom elektrospininga. Eksperimenti su izvedeni u rastvoru 10 mas.% PVB-a u etanolu koji je korišćen kao rastvarač. Nanočestice silike su dodate sa različitim sadržajem od 1, 3 i 5 mas.% SiO2 i modifikovane γ-aminopropiltrietoksi silanom (AMEO silanom). Istražen je uticaj procesnih parametara elektrospininga na nanokompozitna vlakna PVB-SiO2. Struktura PVB-SiO2 nanokompozitnih vlakana je proučavana pomoću optičke mikroskopije i skenirajuće elektronske mikroskopije (SEM). Morfologija proizvedenih nanokompozitnih vlakana i njihova raspodela je analizirana u Image Pro Plus softveru. .",
publisher = "Vojnotehnički institut, Beograd",
journal = "Scientific Technical Review",
title = "The analysis of forming PVB-SiO2 nanocomposite fibers by the electrospinning process, Analiza formiranja PVB-SiO2 nanokompozitnih vlakana pomoću elektrospining procesa",
volume = "61",
number = "3-4",
pages = "34-38",
url = "https://hdl.handle.net/21.15107/rcub_cer_879"
}
Obradović, V., Kojović, A., Stojanović, D. B., Nikolić, N. D., Živković, I., Uskoković, P. S.,& Aleksić, R.. (2011). The analysis of forming PVB-SiO2 nanocomposite fibers by the electrospinning process. in Scientific Technical Review
Vojnotehnički institut, Beograd., 61(3-4), 34-38.
https://hdl.handle.net/21.15107/rcub_cer_879
Obradović V, Kojović A, Stojanović DB, Nikolić ND, Živković I, Uskoković PS, Aleksić R. The analysis of forming PVB-SiO2 nanocomposite fibers by the electrospinning process. in Scientific Technical Review. 2011;61(3-4):34-38.
https://hdl.handle.net/21.15107/rcub_cer_879 .
Obradović, Vera, Kojović, Aleksandar, Stojanović, Dušica B., Nikolić, Nebojša D., Živković, Irena, Uskoković, Petar S., Aleksić, Radoslav, "The analysis of forming PVB-SiO2 nanocomposite fibers by the electrospinning process" in Scientific Technical Review, 61, no. 3-4 (2011):34-38,
https://hdl.handle.net/21.15107/rcub_cer_879 .