TY  - JOUR
AU  - Dojčinović, Marina
AU  - Erić, Olivera
AU  - Rajnović, Dragan
AU  - Šiđanin, Leposava
AU  - Baloš, Sebastijan
PY  - 2012
UR  - http://TechnoRep.tmf.bg.ac.rs/handle/123456789/2057
AB  - The study was designed to investigate the cavitation behavior of the ductile cast iron with microstructure consisting of spheroidal graphite in a predominantly ferrite matrix with 10% pearlite. The experiments were conducted using the ultrasonically induced cavitation test method. The frequency of vibration and the peak-to-peak displacement amplitude of the horn were 20±0.5 kHz and 50ìm, respectively, with separation of 0.5 mm between the sample and the horn tip. In order to obtain the erosion curve, the mass loss measurements were performed after each exposure interval. The mass loss was recorded every 30min for a test period of 240 min. Roughness parameter Ra (the mean roughness), was used to characterize the surfaces. The cavitation rate was 1.85 higher for ductile iron compared with that of carbon steel with similar hardness, because graphite removal produces high stress concentration in cast iron. Compared with conventional mass loss measurements in assessing material degradation in cavitation erosion, surface roughness measurements provide an alternative and convenient method.
PB  - Association of Metallurgical Engineers of Serbia
T2  - Metallurgical & Materials Engineering
T1  - The morphology of ductile cast iron surface damaged by cavitation
EP  - 176
IS  - 3
SP  - 165
VL  - 18
UR  - https://hdl.handle.net/21.15107/rcub_technorep_2057
ER  - 

@article{
author = "Dojčinović, Marina and Erić, Olivera and Rajnović, Dragan and Šiđanin, Leposava and Baloš, Sebastijan",
year = "2012",
abstract = "The study was designed to investigate the cavitation behavior of the ductile cast iron with microstructure consisting of spheroidal graphite in a predominantly ferrite matrix with 10% pearlite. The experiments were conducted using the ultrasonically induced cavitation test method. The frequency of vibration and the peak-to-peak displacement amplitude of the horn were 20±0.5 kHz and 50ìm, respectively, with separation of 0.5 mm between the sample and the horn tip. In order to obtain the erosion curve, the mass loss measurements were performed after each exposure interval. The mass loss was recorded every 30min for a test period of 240 min. Roughness parameter Ra (the mean roughness), was used to characterize the surfaces. The cavitation rate was 1.85 higher for ductile iron compared with that of carbon steel with similar hardness, because graphite removal produces high stress concentration in cast iron. Compared with conventional mass loss measurements in assessing material degradation in cavitation erosion, surface roughness measurements provide an alternative and convenient method.",
publisher = "Association of Metallurgical Engineers of Serbia",
journal = "Metallurgical & Materials Engineering",
title = "The morphology of ductile cast iron surface damaged by cavitation",
pages = "176-165",
number = "3",
volume = "18",
url = "https://hdl.handle.net/21.15107/rcub_technorep_2057"
}

Dojčinović, M., Erić, O., Rajnović, D., Šiđanin, L.,& Baloš, S.. (2012). The morphology of ductile cast iron surface damaged by cavitation. in Metallurgical & Materials Engineering
Association of Metallurgical Engineers of Serbia., 18(3), 165-176.
https://hdl.handle.net/21.15107/rcub_technorep_2057

Dojčinović M, Erić O, Rajnović D, Šiđanin L, Baloš S. The morphology of ductile cast iron surface damaged by cavitation. in Metallurgical & Materials Engineering. 2012;18(3):165-176.
https://hdl.handle.net/21.15107/rcub_technorep_2057 .

Dojčinović, Marina, Erić, Olivera, Rajnović, Dragan, Šiđanin, Leposava, Baloš, Sebastijan, "The morphology of ductile cast iron surface damaged by cavitation" in Metallurgical & Materials Engineering, 18, no. 3 (2012):165-176,
https://hdl.handle.net/21.15107/rcub_technorep_2057 .

TY  - JOUR
AU  - Rajković, Višeslava M.
AU  - Erić, Olivera
AU  - Božić, Dušan
AU  - Mitkov, M.
AU  - Romhanji, Endre
PY  - 2004
UR  - http://TechnoRep.tmf.bg.ac.rs/handle/123456789/646
AB  - The copper matrix has been dispersion strengthened with 3wt.%Al2O3 by mechanical alloying. Commercial alumina powder with an average particle size of 0.75mm was used for alloying. The mechanical alloying process was performed in a planetary ball mill up to 20h in air. After milling all powders were treated in H2 at 4000C for 1h, and finally hot pressing was used for compaction (800oC, 3h, Ar). Structure observations revealed a lamellar structure (Al2O3 particles largely restricted to interlamellar planes between adjacent copper lamellae) accompanied also by structure refinement. These structural changes were mostly completed in the early stage of milling, and retained after compaction. Micro hardness was found to progressively increase with milling time. So, after 5h of milling the micro hardness of the Cu+3twt%Al2O3 compact was 1540MPa, i.e. 2.5 times greater than for the as-received electrolytic copper powder (638MPa) compacted under identical conditions, while after 20h of milling it was 2370 MPa. However after exposing the tested compact at 800oC up to 5h, the achieved hardening effect vanished.
AB  - Osnova bakra disperzno je ojačana mehaničkim legiranjem sa 3tež.,%Al2O3. Za ojačavanje je korišćen komercijalni prah Al2O3 prosečne veličine čestica 0,75mm. Mehaničko legiranje izvršeno je u planetarnom mlinu sa čeličnim kuglama u trajanju do 20h. Posle redukcije (4000C/1h, H2), prahovi su kompaktirani toplim presovanjem (8000C/3h, Ar, 34MPa). Već na početku mlevenja prahova došlo je do usitnjavanja zrna i stvaranja lamelarne strukture, sa česticama Al2O3 raspoređenim po površinama susednih lamela. Ova struktura čestica praha zadržala se i posle kompaktiranja. Sa vremenom mlevenja mikrotvrdoća kompakata raste do 2370MPa. Posle 5h mlevenja mikrotvrdoća kompakata Cu+3tež.%Al2O3 (1540MPa) je 2,5 puta veća u odnosu na mikrotvrdoću kompakta od praha elektrolitičkog bakra komapktiranog pod istim uslovima (638HV). Međutim, efekat ojačavanja gubi se nakon žarenja na 800oC.
PB  - International Institute for the Science of Sintering, Beograd
T2  - Science of Sintering
T1  - Characterization of dispersion strengthened copper with 3wt%Al2O3 by mechanical alloying
EP  - 211
IS  - 3
SP  - 205
VL  - 36
UR  - https://hdl.handle.net/21.15107/rcub_technorep_646
ER  - 

@article{
author = "Rajković, Višeslava M. and Erić, Olivera and Božić, Dušan and Mitkov, M. and Romhanji, Endre",
year = "2004",
abstract = "The copper matrix has been dispersion strengthened with 3wt.%Al2O3 by mechanical alloying. Commercial alumina powder with an average particle size of 0.75mm was used for alloying. The mechanical alloying process was performed in a planetary ball mill up to 20h in air. After milling all powders were treated in H2 at 4000C for 1h, and finally hot pressing was used for compaction (800oC, 3h, Ar). Structure observations revealed a lamellar structure (Al2O3 particles largely restricted to interlamellar planes between adjacent copper lamellae) accompanied also by structure refinement. These structural changes were mostly completed in the early stage of milling, and retained after compaction. Micro hardness was found to progressively increase with milling time. So, after 5h of milling the micro hardness of the Cu+3twt%Al2O3 compact was 1540MPa, i.e. 2.5 times greater than for the as-received electrolytic copper powder (638MPa) compacted under identical conditions, while after 20h of milling it was 2370 MPa. However after exposing the tested compact at 800oC up to 5h, the achieved hardening effect vanished., Osnova bakra disperzno je ojačana mehaničkim legiranjem sa 3tež.,%Al2O3. Za ojačavanje je korišćen komercijalni prah Al2O3 prosečne veličine čestica 0,75mm. Mehaničko legiranje izvršeno je u planetarnom mlinu sa čeličnim kuglama u trajanju do 20h. Posle redukcije (4000C/1h, H2), prahovi su kompaktirani toplim presovanjem (8000C/3h, Ar, 34MPa). Već na početku mlevenja prahova došlo je do usitnjavanja zrna i stvaranja lamelarne strukture, sa česticama Al2O3 raspoređenim po površinama susednih lamela. Ova struktura čestica praha zadržala se i posle kompaktiranja. Sa vremenom mlevenja mikrotvrdoća kompakata raste do 2370MPa. Posle 5h mlevenja mikrotvrdoća kompakata Cu+3tež.%Al2O3 (1540MPa) je 2,5 puta veća u odnosu na mikrotvrdoću kompakta od praha elektrolitičkog bakra komapktiranog pod istim uslovima (638HV). Međutim, efekat ojačavanja gubi se nakon žarenja na 800oC.",
publisher = "International Institute for the Science of Sintering, Beograd",
journal = "Science of Sintering",
title = "Characterization of dispersion strengthened copper with 3wt%Al2O3 by mechanical alloying",
pages = "211-205",
number = "3",
volume = "36",
url = "https://hdl.handle.net/21.15107/rcub_technorep_646"
}

Rajković, V. M., Erić, O., Božić, D., Mitkov, M.,& Romhanji, E.. (2004). Characterization of dispersion strengthened copper with 3wt%Al2O3 by mechanical alloying. in Science of Sintering
International Institute for the Science of Sintering, Beograd., 36(3), 205-211.
https://hdl.handle.net/21.15107/rcub_technorep_646

Rajković VM, Erić O, Božić D, Mitkov M, Romhanji E. Characterization of dispersion strengthened copper with 3wt%Al2O3 by mechanical alloying. in Science of Sintering. 2004;36(3):205-211.
https://hdl.handle.net/21.15107/rcub_technorep_646 .

Rajković, Višeslava M., Erić, Olivera, Božić, Dušan, Mitkov, M., Romhanji, Endre, "Characterization of dispersion strengthened copper with 3wt%Al2O3 by mechanical alloying" in Science of Sintering, 36, no. 3 (2004):205-211,
https://hdl.handle.net/21.15107/rcub_technorep_646 .