TY  - CONF
AU  - Cvijović, Zorica M.
AU  - Vratnica, M.
AU  - Cvijović-Alagić, Ivana
PY  - 2009
UR  - http://TechnoRep.tmf.bg.ac.rs/handle/123456789/5543
AB  - To identify the most important parameters of multiscale microstructural features influencing the fracture modes and resistance to damage, detailed microstructural and fractographic analysis of overaged 7000 alloy plates are performed using the broken plane-strain fracture toughness, K-Ic, test specimens. The geometric characteristics of differently sized second-phase particles are changed by the compositional variations. It was found that the fracture process involves three main micromechanisms. The dominant fracture mode changes with alloy purity, leading to fracture toughness degradation. Quantitative description of fractures by profilometry confirmed that crack initiation and propagation is fostered by the coarse Fe- and Si-rich particles. (C) 2009 Elsevier B. V. All rights reserved
C3  - Procedia Engineering
T1  - The influences of multiscale-sized second-phase particles on fracture behaviour of overaged 7000 alloys
EP  - 38
IS  - 1
SP  - 35
VL  - 1
DO  - 10.1016/j.proeng.2009.06.010
ER  - 

@conference{
author = "Cvijović, Zorica M. and Vratnica, M. and Cvijović-Alagić, Ivana",
year = "2009",
abstract = "To identify the most important parameters of multiscale microstructural features influencing the fracture modes and resistance to damage, detailed microstructural and fractographic analysis of overaged 7000 alloy plates are performed using the broken plane-strain fracture toughness, K-Ic, test specimens. The geometric characteristics of differently sized second-phase particles are changed by the compositional variations. It was found that the fracture process involves three main micromechanisms. The dominant fracture mode changes with alloy purity, leading to fracture toughness degradation. Quantitative description of fractures by profilometry confirmed that crack initiation and propagation is fostered by the coarse Fe- and Si-rich particles. (C) 2009 Elsevier B. V. All rights reserved",
journal = "Procedia Engineering",
title = "The influences of multiscale-sized second-phase particles on fracture behaviour of overaged 7000 alloys",
pages = "38-35",
number = "1",
volume = "1",
doi = "10.1016/j.proeng.2009.06.010"
}

Cvijović, Z. M., Vratnica, M.,& Cvijović-Alagić, I.. (2009). The influences of multiscale-sized second-phase particles on fracture behaviour of overaged 7000 alloys. in Procedia Engineering, 1(1), 35-38.
https://doi.org/10.1016/j.proeng.2009.06.010

Cvijović ZM, Vratnica M, Cvijović-Alagić I. The influences of multiscale-sized second-phase particles on fracture behaviour of overaged 7000 alloys. in Procedia Engineering. 2009;1(1):35-38.
doi:10.1016/j.proeng.2009.06.010 .

Cvijović, Zorica M., Vratnica, M., Cvijović-Alagić, Ivana, "The influences of multiscale-sized second-phase particles on fracture behaviour of overaged 7000 alloys" in Procedia Engineering, 1, no. 1 (2009):35-38,
https://doi.org/10.1016/j.proeng.2009.06.010 . .

TY  - JOUR
AU  - Cvijović, Z.
AU  - Vratnica, M.
AU  - Gerić, K.
PY  - 2008
UR  - http://TechnoRep.tmf.bg.ac.rs/handle/123456789/5550
AB  - In this paper, an attempt is made to correlate the fatigue damage in 7000 aluminium alloys with different impurity contents to the microstructural features and to explain their interdependence through fractographic observations. The Paris constants of these alloys in the form of hot-forged plates subjected to the overaged T73 temper are evaluated and differences in the fatigue crack growth rate described by striation spacing measurements. Scanning electron microscopy analysis of fatigue fracture surfaces revealed that the type and morphological parameters of coarse intermetallic particles play a critical role in fatigue crack growth behaviour. The elemental distribution determined by means of energy-dispersive spectroscopy analysis showed that the fractured particles accelerating the crack advances are larger particles of Fe-rich phases. The fatigue crack growth rate increases considerably with increasing amounts of these particles. The smaller η, S and Mg2Si particles contribute beneficially to fatigue life.
PB  - The Royal Microscopical Society
T2  - Journal of Microscopy
T1  - Fractographic analysis of fatigue damage in 7000 aluminium alloys
EP  - 594
IS  - 3
SP  - 589
VL  - 232
DO  - 10.1111/j.1365-2818.2008.02122.x
ER  - 

@article{
author = "Cvijović, Z. and Vratnica, M. and Gerić, K.",
year = "2008",
abstract = "In this paper, an attempt is made to correlate the fatigue damage in 7000 aluminium alloys with different impurity contents to the microstructural features and to explain their interdependence through fractographic observations. The Paris constants of these alloys in the form of hot-forged plates subjected to the overaged T73 temper are evaluated and differences in the fatigue crack growth rate described by striation spacing measurements. Scanning electron microscopy analysis of fatigue fracture surfaces revealed that the type and morphological parameters of coarse intermetallic particles play a critical role in fatigue crack growth behaviour. The elemental distribution determined by means of energy-dispersive spectroscopy analysis showed that the fractured particles accelerating the crack advances are larger particles of Fe-rich phases. The fatigue crack growth rate increases considerably with increasing amounts of these particles. The smaller η, S and Mg2Si particles contribute beneficially to fatigue life.",
publisher = "The Royal Microscopical Society",
journal = "Journal of Microscopy",
title = "Fractographic analysis of fatigue damage in 7000 aluminium alloys",
pages = "594-589",
number = "3",
volume = "232",
doi = "10.1111/j.1365-2818.2008.02122.x"
}

Cvijović, Z., Vratnica, M.,& Gerić, K.. (2008). Fractographic analysis of fatigue damage in 7000 aluminium alloys. in Journal of Microscopy
The Royal Microscopical Society., 232(3), 589-594.
https://doi.org/10.1111/j.1365-2818.2008.02122.x

Cvijović Z, Vratnica M, Gerić K. Fractographic analysis of fatigue damage in 7000 aluminium alloys. in Journal of Microscopy. 2008;232(3):589-594.
doi:10.1111/j.1365-2818.2008.02122.x .

Cvijović, Z., Vratnica, M., Gerić, K., "Fractographic analysis of fatigue damage in 7000 aluminium alloys" in Journal of Microscopy, 232, no. 3 (2008):589-594,
https://doi.org/10.1111/j.1365-2818.2008.02122.x . .

TY  - JOUR
AU  - Vratnica, M.
AU  - Cvijović, Zorica
AU  - Degische, H.P.
AU  - Requena, G.C.
PY  - 2006
UR  - http://TechnoRep.tmf.bg.ac.rs/handle/123456789/5469
AB  - The effect of coarse intermetallic particles on the fracture process in 7000 alloy forgings was investigated using three alloys with different (Fe + Si) impurity levels. The intermetallic particles were identified by selective etching and energy dispersive spectroscopy analysis conducted on a scanning electron microscope. Their geometrical parameters were estimated by image analysis and then correlated with area fractions of different fracture modes on the broken fracture toughness test specimens. It was found that the dominant fracture mode varies with the (Fe + Si) content. The coarse voiding at large intermetallic particles increases systematically with an increase of the impurity level, which in turn increases the amount and size of particles containing Fe and Si while decreasing their spacing. That the crack nucleation and propagation are accelerated by these particles was revealed by in situ scanning electron microscopy observation of the fracture process.
PB  - Wiley-Blackwell
T2  - Journal of Microscopy
T1  - The effect of coarse intermetallic particles on the fracture process in forged 7000 alloys
EP  - 120
IS  - 1
SP  - 117
VL  - 224
DO  - 10.1111/j.1365-2818.2006.01683.x
ER  - 

@article{
author = "Vratnica, M. and Cvijović, Zorica and Degische, H.P. and Requena, G.C.",
year = "2006",
abstract = "The effect of coarse intermetallic particles on the fracture process in 7000 alloy forgings was investigated using three alloys with different (Fe + Si) impurity levels. The intermetallic particles were identified by selective etching and energy dispersive spectroscopy analysis conducted on a scanning electron microscope. Their geometrical parameters were estimated by image analysis and then correlated with area fractions of different fracture modes on the broken fracture toughness test specimens. It was found that the dominant fracture mode varies with the (Fe + Si) content. The coarse voiding at large intermetallic particles increases systematically with an increase of the impurity level, which in turn increases the amount and size of particles containing Fe and Si while decreasing their spacing. That the crack nucleation and propagation are accelerated by these particles was revealed by in situ scanning electron microscopy observation of the fracture process.",
publisher = "Wiley-Blackwell",
journal = "Journal of Microscopy",
title = "The effect of coarse intermetallic particles on the fracture process in forged 7000 alloys",
pages = "120-117",
number = "1",
volume = "224",
doi = "10.1111/j.1365-2818.2006.01683.x"
}

Vratnica, M., Cvijović, Z., Degische, H.P.,& Requena, G.C.. (2006). The effect of coarse intermetallic particles on the fracture process in forged 7000 alloys. in Journal of Microscopy
Wiley-Blackwell., 224(1), 117-120.
https://doi.org/10.1111/j.1365-2818.2006.01683.x

Vratnica M, Cvijović Z, Degische H, Requena G. The effect of coarse intermetallic particles on the fracture process in forged 7000 alloys. in Journal of Microscopy. 2006;224(1):117-120.
doi:10.1111/j.1365-2818.2006.01683.x .

Vratnica, M., Cvijović, Zorica, Degische, H.P., Requena, G.C., "The effect of coarse intermetallic particles on the fracture process in forged 7000 alloys" in Journal of Microscopy, 224, no. 1 (2006):117-120,
https://doi.org/10.1111/j.1365-2818.2006.01683.x . .

TY  - JOUR
AU  - Cvijović, Zorica
AU  - Vratnica, M.
AU  - Rakin, M.
PY  - 2006
UR  - http://TechnoRep.tmf.bg.ac.rs/handle/123456789/5451
AB  - In this article, a multiple micromechanisms-based model that quantitatively relates the plane-strain fracture toughness, KIC, of overaged 7000 alloy forgings to their microstructural attributes, fracture surface morphology and basic tensile properties is developed. To verify the proposed model, extensive microstructural and fractographic analyses along with mechanical tests are carried out using three industrially produced alloys with different contents of Fe and Si impurities. The fracture mechanisms are identified and individual contributions to the overall fracture are quantitatively assessed. The fracture toughness is then calculated using the experimentally obtained average values of relevant mechanical properties, area fractions of main fracture modes and microstructural parameters such as volume fraction of coarse intermetallic (IM) particles, their size and spacing, density of intragranular precipitates, number and width of the precipitate-free zones (PFZ). The proposed model correctly predicts the effect of individual microstructural parameters on the overall fracture behaviour.
PB  - Elsevier
T2  - Materials Science and Engineering A
T1  - Micromechanical modelling of fracture toughness in overaged 7000 alloy forgings
EP  - 346
IS  - 1-2
SP  - 339
VL  - 434
DO  - 10.1016/j.msea.2006.07.018
ER  - 

@article{
author = "Cvijović, Zorica and Vratnica, M. and Rakin, M.",
year = "2006",
abstract = "In this article, a multiple micromechanisms-based model that quantitatively relates the plane-strain fracture toughness, KIC, of overaged 7000 alloy forgings to their microstructural attributes, fracture surface morphology and basic tensile properties is developed. To verify the proposed model, extensive microstructural and fractographic analyses along with mechanical tests are carried out using three industrially produced alloys with different contents of Fe and Si impurities. The fracture mechanisms are identified and individual contributions to the overall fracture are quantitatively assessed. The fracture toughness is then calculated using the experimentally obtained average values of relevant mechanical properties, area fractions of main fracture modes and microstructural parameters such as volume fraction of coarse intermetallic (IM) particles, their size and spacing, density of intragranular precipitates, number and width of the precipitate-free zones (PFZ). The proposed model correctly predicts the effect of individual microstructural parameters on the overall fracture behaviour.",
publisher = "Elsevier",
journal = "Materials Science and Engineering A",
title = "Micromechanical modelling of fracture toughness in overaged 7000 alloy forgings",
pages = "346-339",
number = "1-2",
volume = "434",
doi = "10.1016/j.msea.2006.07.018"
}

Cvijović, Z., Vratnica, M.,& Rakin, M.. (2006). Micromechanical modelling of fracture toughness in overaged 7000 alloy forgings. in Materials Science and Engineering A
Elsevier., 434(1-2), 339-346.
https://doi.org/10.1016/j.msea.2006.07.018

Cvijović Z, Vratnica M, Rakin M. Micromechanical modelling of fracture toughness in overaged 7000 alloy forgings. in Materials Science and Engineering A. 2006;434(1-2):339-346.
doi:10.1016/j.msea.2006.07.018 .

Cvijović, Zorica, Vratnica, M., Rakin, M., "Micromechanical modelling of fracture toughness in overaged 7000 alloy forgings" in Materials Science and Engineering A, 434, no. 1-2 (2006):339-346,
https://doi.org/10.1016/j.msea.2006.07.018 . .