Nanostructured calcium phosphate functionally graded materials (FGMs) with simultaneous gradients of density, phase composition, and mechanical properties were fabricated by consecutive uniaxial pressing of stoichiometric (SHAp) and calcium deficient (CDHAp) hydroxyapatite powders in multilayered samples and reaction sintering. During sintering procedure SHAp composition remained stable (HAp) while CDHAp was phase transformed in biphasic calcium phosphate (BCP, i.e. HAp+β-TCP) yielding HAp/BCP FGMs. To reduce mismatch stress between adjacent layers, generated during sintering, gradient of phase composition was optimized by introducing intermediate layer(s) made from mixture of SHAp and CDHAp in appropriate mass ratio. Optimal processing conditions for preparation of nanostructured ceramics were provided via two-step sintering. High-quality FGMs structure, without delamination, cracks and micro-structural damages was observed by SEM technique; moreover, a detailed examination by FE−SEM ...established the unidirectional (perpendicular with respect to the layers) gradual change of microstructure, from fully dense to ~40% of porosity. Detailed micro-Raman and FTIR spectroscopy studies showed increase of β-TCP amount along the FGMs height, confirming gradient of phase composition. Mechanical properties measured by microindentation revealed gradual change of microhardness from 650 to 115 HV, with simultaneous change of Young's modulus from 92 to 24 GPa.
Bilateral cooperation program between the Republic of Serbia and the Republic of Slovenia, Project 451-03-1251/2012-09/06
Note:
This is the peer‐reviewed version of the paper Marković, S., Lukić, M.J., Škapin, S.D., Stojanović, B., Uskoković, D., 2015. Designing, fabrication and characterization of nanostructured functionally graded HAp/BCP ceramics. Ceramics International 41, 2654–2667. https://doi.org/10.1016/j.ceramint.2014.10.079
TY - JOUR
AU - Marković, Smilja
AU - Lukić, Miodrag J.
AU - Škapin, Srečo Davor
AU - Stojanović, Boban
AU - Uskoković, Dragan
PY - 2015
UR - https://dais.sanu.ac.rs/123456789/588
AB - Nanostructured calcium phosphate functionally graded materials (FGMs) with simultaneous gradients of density, phase composition, and mechanical properties were fabricated by consecutive uniaxial pressing of stoichiometric (SHAp) and calcium deficient (CDHAp) hydroxyapatite powders in multilayered samples and reaction sintering. During sintering procedure SHAp composition remained stable (HAp) while CDHAp was phase transformed in biphasic calcium phosphate (BCP, i.e. HAp+β-TCP) yielding HAp/BCP FGMs. To reduce mismatch stress between adjacent layers, generated during sintering, gradient of phase composition was optimized by introducing intermediate layer(s) made from mixture of SHAp and CDHAp in appropriate mass ratio. Optimal processing conditions for preparation of nanostructured ceramics were provided via two-step sintering. High-quality FGMs structure, without delamination, cracks and micro-structural damages was observed by SEM technique; moreover, a detailed examination by FE−SEM established the unidirectional (perpendicular with respect to the layers) gradual change of microstructure, from fully dense to ~40% of porosity. Detailed micro-Raman and FTIR spectroscopy studies showed increase of β-TCP amount along the FGMs height, confirming gradient of phase composition. Mechanical properties measured by microindentation revealed gradual change of microhardness from 650 to 115 HV, with simultaneous change of Young's modulus from 92 to 24 GPa.
PB - Elsevier
T2 - Ceramics International
T1 - Designing, fabrication and characterization of nanostructured functionally graded HAp/BCP ceramics
SP - 2654
EP - 2667
VL - 41
VL - 41
IS - 2, Part B
IS - 2
DO - 10.1016/j.ceramint.2014.10.079
UR - https://hdl.handle.net/21.15107/rcub_dais_588
ER -
@article{
author = "Marković, Smilja and Lukić, Miodrag J. and Škapin, Srečo Davor and Stojanović, Boban and Uskoković, Dragan",
year = "2015",
abstract = "Nanostructured calcium phosphate functionally graded materials (FGMs) with simultaneous gradients of density, phase composition, and mechanical properties were fabricated by consecutive uniaxial pressing of stoichiometric (SHAp) and calcium deficient (CDHAp) hydroxyapatite powders in multilayered samples and reaction sintering. During sintering procedure SHAp composition remained stable (HAp) while CDHAp was phase transformed in biphasic calcium phosphate (BCP, i.e. HAp+β-TCP) yielding HAp/BCP FGMs. To reduce mismatch stress between adjacent layers, generated during sintering, gradient of phase composition was optimized by introducing intermediate layer(s) made from mixture of SHAp and CDHAp in appropriate mass ratio. Optimal processing conditions for preparation of nanostructured ceramics were provided via two-step sintering. High-quality FGMs structure, without delamination, cracks and micro-structural damages was observed by SEM technique; moreover, a detailed examination by FE−SEM established the unidirectional (perpendicular with respect to the layers) gradual change of microstructure, from fully dense to ~40% of porosity. Detailed micro-Raman and FTIR spectroscopy studies showed increase of β-TCP amount along the FGMs height, confirming gradient of phase composition. Mechanical properties measured by microindentation revealed gradual change of microhardness from 650 to 115 HV, with simultaneous change of Young's modulus from 92 to 24 GPa.",
publisher = "Elsevier",
journal = "Ceramics International",
title = "Designing, fabrication and characterization of nanostructured functionally graded HAp/BCP ceramics",
pages = "2654-2667",
volume = "41, 41",
number = "2, Part B, 2",
doi = "10.1016/j.ceramint.2014.10.079",
url = "https://hdl.handle.net/21.15107/rcub_dais_588"
}
Marković, S., Lukić, M. J., Škapin, S. D., Stojanović, B.,& Uskoković, D.. (2015). Designing, fabrication and characterization of nanostructured functionally graded HAp/BCP ceramics. in Ceramics International
Elsevier., 41(2, Part B), 2654-2667.
https://doi.org/10.1016/j.ceramint.2014.10.079
https://hdl.handle.net/21.15107/rcub_dais_588
Marković S, Lukić MJ, Škapin SD, Stojanović B, Uskoković D. Designing, fabrication and characterization of nanostructured functionally graded HAp/BCP ceramics. in Ceramics International. 2015;41(2, Part B):2654-2667.
doi:10.1016/j.ceramint.2014.10.079
https://hdl.handle.net/21.15107/rcub_dais_588 .
Marković, Smilja, Lukić, Miodrag J., Škapin, Srečo Davor, Stojanović, Boban, Uskoković, Dragan, "Designing, fabrication and characterization of nanostructured functionally graded HAp/BCP ceramics" in Ceramics International, 41, no. 2, Part B (2015):2654-2667,
https://doi.org/10.1016/j.ceramint.2014.10.079 .,
https://hdl.handle.net/21.15107/rcub_dais_588 .
