TY  - JOUR
AU  - Vratnica, Maja
AU  - Cvijović, Zorica
AU  - Radović, Nenad
PY  - 2008
UR  - http://TechnoRep.tmf.bg.ac.rs/handle/123456789/1203
AB  - To provide an understanding of how compositional variations affect the microstructural parameters associated with coarse intermetallic (IM) particles and the fracture toughness in AA 7000 aluminum forgings, a microstructural and fractographic analysis as well as mechanical tests were carried out on three industrially produced Al-Zn-Mg-Cu alloys with different contents of impurities (Fe+Si). Light optical microscopy and image analysis were used to assess the volume fraction, size and distribution of all the soluble and insoluble coarse ( gt  0.1 mu m) IM particles identified in the corresponding R-C and L-R planes for T73-type heat treatments by selective etching and energy-dispersive X-ray spectroscopy. These quantitative data were correlated with the plain-strain fracture toughness, K-IC, with the results being, used to produce useful information on alloy design and thermomechanical processing via microstructural control. The scanning electron microscope observation of fracture surface features and an estimation of the area fractions of different fracture modes in the plastic zone segments of a test specimen showed that multiple failure mechanisms occurred with coarse voiding at the intermetallics becoming more important as the fraction of coarse IM particles increases. A quantitative assessment of the relevant microstructural and fractographic parameters will be utilized for developing and verifying a multiple micromechanisms-based model for fracture toughness.
PB  - Institute of Metals and Technology
T2  - Materiali in Tehnologije
T1  - The effect of compositional variations on the fracture toughness of 7000 al-alloys
EP  - 196
IS  - 5
SP  - 191
VL  - 42
UR  - https://hdl.handle.net/21.15107/rcub_technorep_1203
ER  - 

@article{
author = "Vratnica, Maja and Cvijović, Zorica and Radović, Nenad",
year = "2008",
abstract = "To provide an understanding of how compositional variations affect the microstructural parameters associated with coarse intermetallic (IM) particles and the fracture toughness in AA 7000 aluminum forgings, a microstructural and fractographic analysis as well as mechanical tests were carried out on three industrially produced Al-Zn-Mg-Cu alloys with different contents of impurities (Fe+Si). Light optical microscopy and image analysis were used to assess the volume fraction, size and distribution of all the soluble and insoluble coarse ( gt  0.1 mu m) IM particles identified in the corresponding R-C and L-R planes for T73-type heat treatments by selective etching and energy-dispersive X-ray spectroscopy. These quantitative data were correlated with the plain-strain fracture toughness, K-IC, with the results being, used to produce useful information on alloy design and thermomechanical processing via microstructural control. The scanning electron microscope observation of fracture surface features and an estimation of the area fractions of different fracture modes in the plastic zone segments of a test specimen showed that multiple failure mechanisms occurred with coarse voiding at the intermetallics becoming more important as the fraction of coarse IM particles increases. A quantitative assessment of the relevant microstructural and fractographic parameters will be utilized for developing and verifying a multiple micromechanisms-based model for fracture toughness.",
publisher = "Institute of Metals and Technology",
journal = "Materiali in Tehnologije",
title = "The effect of compositional variations on the fracture toughness of 7000 al-alloys",
pages = "196-191",
number = "5",
volume = "42",
url = "https://hdl.handle.net/21.15107/rcub_technorep_1203"
}

Vratnica, M., Cvijović, Z.,& Radović, N.. (2008). The effect of compositional variations on the fracture toughness of 7000 al-alloys. in Materiali in Tehnologije
Institute of Metals and Technology., 42(5), 191-196.
https://hdl.handle.net/21.15107/rcub_technorep_1203

Vratnica M, Cvijović Z, Radović N. The effect of compositional variations on the fracture toughness of 7000 al-alloys. in Materiali in Tehnologije. 2008;42(5):191-196.
https://hdl.handle.net/21.15107/rcub_technorep_1203 .

Vratnica, Maja, Cvijović, Zorica, Radović, Nenad, "The effect of compositional variations on the fracture toughness of 7000 al-alloys" in Materiali in Tehnologije, 42, no. 5 (2008):191-196,
https://hdl.handle.net/21.15107/rcub_technorep_1203 .

TY  - JOUR
AU  - Cvijović, Zorica
AU  - Vratnica, Maja
AU  - Rakin, Marko
AU  - Cvijović-Alagić, Ivana
PY  - 2008
UR  - http://TechnoRep.tmf.bg.ac.rs/handle/123456789/1292
AB  - An attempt has been made to model the plane-strain fracture toughness, KIc, in Al-Zn-Mg-Cu alloy forgings subjected to overageing. The proposed model, based on the multiple micromechanisms, reveals the quantitative relations between fracture toughness, fraction of all fracture modes and microstructural parameters associated with multiscale-sized second-phase particles and precipitate-free zones. The new model is validated by the present quantitative data of microstructural and fractographic analysis performed along with mechanical tests on hot-forged plates in T73 condition. The relevant parameters changed by the compositional variations were determined in two orientations. It was found that the predicted KIc values represent the tendency of fracture toughness change well. The new model provides better agreement for the case of dominant transgranular fracture mode.
PB  - Taylor & Francis Ltd, Abingdon
T2  - Philosophical Magazine
T1  - Micromechanical model for fracture toughness prediction in Al-Zn-Mg-Cu alloy forgings
EP  - 3179
IS  - 27
SP  - 3153
VL  - 88
DO  - 10.1080/14786430802502559
ER  - 

@article{
author = "Cvijović, Zorica and Vratnica, Maja and Rakin, Marko and Cvijović-Alagić, Ivana",
year = "2008",
abstract = "An attempt has been made to model the plane-strain fracture toughness, KIc, in Al-Zn-Mg-Cu alloy forgings subjected to overageing. The proposed model, based on the multiple micromechanisms, reveals the quantitative relations between fracture toughness, fraction of all fracture modes and microstructural parameters associated with multiscale-sized second-phase particles and precipitate-free zones. The new model is validated by the present quantitative data of microstructural and fractographic analysis performed along with mechanical tests on hot-forged plates in T73 condition. The relevant parameters changed by the compositional variations were determined in two orientations. It was found that the predicted KIc values represent the tendency of fracture toughness change well. The new model provides better agreement for the case of dominant transgranular fracture mode.",
publisher = "Taylor & Francis Ltd, Abingdon",
journal = "Philosophical Magazine",
title = "Micromechanical model for fracture toughness prediction in Al-Zn-Mg-Cu alloy forgings",
pages = "3179-3153",
number = "27",
volume = "88",
doi = "10.1080/14786430802502559"
}

Cvijović, Z., Vratnica, M., Rakin, M.,& Cvijović-Alagić, I.. (2008). Micromechanical model for fracture toughness prediction in Al-Zn-Mg-Cu alloy forgings. in Philosophical Magazine
Taylor & Francis Ltd, Abingdon., 88(27), 3153-3179.
https://doi.org/10.1080/14786430802502559

Cvijović Z, Vratnica M, Rakin M, Cvijović-Alagić I. Micromechanical model for fracture toughness prediction in Al-Zn-Mg-Cu alloy forgings. in Philosophical Magazine. 2008;88(27):3153-3179.
doi:10.1080/14786430802502559 .

Cvijović, Zorica, Vratnica, Maja, Rakin, Marko, Cvijović-Alagić, Ivana, "Micromechanical model for fracture toughness prediction in Al-Zn-Mg-Cu alloy forgings" in Philosophical Magazine, 88, no. 27 (2008):3153-3179,
https://doi.org/10.1080/14786430802502559 . .

TY  - JOUR
AU  - Cvijović, Zorica
AU  - Rakin, Marko
AU  - Vratnica, Maja
AU  - Cvijović, Ivana
PY  - 2008
UR  - http://TechnoRep.tmf.bg.ac.rs/handle/123456789/1320
AB  - The effects of microstructural parameters associated with the coarse intermetallic phases particles and precipitates on the fracture toughness of the overaged 7000 alloy forgings are investigated. Detailed microstructural and fractographic analysis together with fracture toughness tests are carried out using three alloys with different (Fe + Si) contents. The fracture mechanisms are identified and area fractions of different fracture modes are assessed. The data are then quantitatively correlated to plane-strain fracture toughness, K-Ic, and the bulk microstructural attributes estimated via image analysis. A multiple micromechanism-based model is developed, which accurately describes the dependence of K-Ic on individual microstructural parameters.
PB  - Pergamon-Elsevier Science Ltd, Oxford
T2  - Engineering Fracture Mechanics
T1  - Microstructural dependence of fracture toughness in high-strength 7000 forging alloys
EP  - 2129
IS  - 8
SP  - 2115
VL  - 75
DO  - 10.1016/j.engfracmech.2007.10.010
ER  - 

@article{
author = "Cvijović, Zorica and Rakin, Marko and Vratnica, Maja and Cvijović, Ivana",
year = "2008",
abstract = "The effects of microstructural parameters associated with the coarse intermetallic phases particles and precipitates on the fracture toughness of the overaged 7000 alloy forgings are investigated. Detailed microstructural and fractographic analysis together with fracture toughness tests are carried out using three alloys with different (Fe + Si) contents. The fracture mechanisms are identified and area fractions of different fracture modes are assessed. The data are then quantitatively correlated to plane-strain fracture toughness, K-Ic, and the bulk microstructural attributes estimated via image analysis. A multiple micromechanism-based model is developed, which accurately describes the dependence of K-Ic on individual microstructural parameters.",
publisher = "Pergamon-Elsevier Science Ltd, Oxford",
journal = "Engineering Fracture Mechanics",
title = "Microstructural dependence of fracture toughness in high-strength 7000 forging alloys",
pages = "2129-2115",
number = "8",
volume = "75",
doi = "10.1016/j.engfracmech.2007.10.010"
}

Cvijović, Z., Rakin, M., Vratnica, M.,& Cvijović, I.. (2008). Microstructural dependence of fracture toughness in high-strength 7000 forging alloys. in Engineering Fracture Mechanics
Pergamon-Elsevier Science Ltd, Oxford., 75(8), 2115-2129.
https://doi.org/10.1016/j.engfracmech.2007.10.010

Cvijović Z, Rakin M, Vratnica M, Cvijović I. Microstructural dependence of fracture toughness in high-strength 7000 forging alloys. in Engineering Fracture Mechanics. 2008;75(8):2115-2129.
doi:10.1016/j.engfracmech.2007.10.010 .

Cvijović, Zorica, Rakin, Marko, Vratnica, Maja, Cvijović, Ivana, "Microstructural dependence of fracture toughness in high-strength 7000 forging alloys" in Engineering Fracture Mechanics, 75, no. 8 (2008):2115-2129,
https://doi.org/10.1016/j.engfracmech.2007.10.010 . .

TY  - JOUR
AU  - Vratnica, Maja
AU  - Cvijović, Zorica
AU  - Rakin, Marko
AU  - Cvijović, Ivana
PY  - 2007
UR  - http://TechnoRep.tmf.bg.ac.rs/handle/123456789/1046
AB  - An attempt to develop a multiple micromechanism-based model for predicting plane-strain fracture toughness, KIc, of overaged 7000 alloy forgings has been made. The proposed model reveals the quantitative relations between the fracture toughness, fraction of the main fracture modes and parameters such as volume fraction, size and density of differently sized second-phase particles and precipitate-free zones. The new model is validated by the present quantitative data of microstructural and fractographic analysis performed along with mechanical tests on hot-forged plates subjected to the T73 temper. The relative parameters changed by the compositional variations were determined in the R-L and L-R orientations. It was found that the predicted KIc values well represent the tendency of fracture toughness change. The new model provides better agreement for the case of dominant transgranular fracture mode represented in the R-L orientation. .
PB  - Savez inženjera metalurgije Srbije, Beograd
T2  - Metalurgija
T1  - A model for predicting fracture toughness in overaged 7000 alloy forgings
EP  - 300
IS  - 4
SP  - 293
VL  - 13
UR  - https://hdl.handle.net/21.15107/rcub_technorep_1046
ER  - 

@article{
author = "Vratnica, Maja and Cvijović, Zorica and Rakin, Marko and Cvijović, Ivana",
year = "2007",
abstract = "An attempt to develop a multiple micromechanism-based model for predicting plane-strain fracture toughness, KIc, of overaged 7000 alloy forgings has been made. The proposed model reveals the quantitative relations between the fracture toughness, fraction of the main fracture modes and parameters such as volume fraction, size and density of differently sized second-phase particles and precipitate-free zones. The new model is validated by the present quantitative data of microstructural and fractographic analysis performed along with mechanical tests on hot-forged plates subjected to the T73 temper. The relative parameters changed by the compositional variations were determined in the R-L and L-R orientations. It was found that the predicted KIc values well represent the tendency of fracture toughness change. The new model provides better agreement for the case of dominant transgranular fracture mode represented in the R-L orientation. .",
publisher = "Savez inženjera metalurgije Srbije, Beograd",
journal = "Metalurgija",
title = "A model for predicting fracture toughness in overaged 7000 alloy forgings",
pages = "300-293",
number = "4",
volume = "13",
url = "https://hdl.handle.net/21.15107/rcub_technorep_1046"
}

Vratnica, M., Cvijović, Z., Rakin, M.,& Cvijović, I.. (2007). A model for predicting fracture toughness in overaged 7000 alloy forgings. in Metalurgija
Savez inženjera metalurgije Srbije, Beograd., 13(4), 293-300.
https://hdl.handle.net/21.15107/rcub_technorep_1046

Vratnica M, Cvijović Z, Rakin M, Cvijović I. A model for predicting fracture toughness in overaged 7000 alloy forgings. in Metalurgija. 2007;13(4):293-300.
https://hdl.handle.net/21.15107/rcub_technorep_1046 .

Vratnica, Maja, Cvijović, Zorica, Rakin, Marko, Cvijović, Ivana, "A model for predicting fracture toughness in overaged 7000 alloy forgings" in Metalurgija, 13, no. 4 (2007):293-300,
https://hdl.handle.net/21.15107/rcub_technorep_1046 .