Final published version
Research output: Contribution to Journal/Magazine › Journal article › peer-review
Research output: Contribution to Journal/Magazine › Journal article › peer-review
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TY - JOUR
T1 - Phase stability and rapid consolidation of hydroxyapatite-zirconia nano-coprecipitates made using continuous hydrothermal flow synthesis
AU - Chaudhry, A.A.
AU - Yan, H.
AU - Viola, G.
AU - Reece, M.J.
AU - Knowles, J.C.
AU - Gong, K.
AU - Rehman, I.
AU - Darr, J.A.
PY - 2012
Y1 - 2012
N2 - A rapid and continuous hydrothermal route for the synthesis of nano-sized hydroxyapatite rods co-precipitated with calcium-doped zirconia nanoparticles using a superheated water flow at 450°C and 24.1MPa as a crystallizing medium is described. Hydroxyapatite and calcium-doped zirconia phases in the powder mixtures could be clearly identified based on particle size and morphology under transmission electron microscopy. Retention of a nanostructure after sintering is crucial to load-bearing applications of hydroxyapatite-based ceramics. Therefore, rapid consolidation of the co-precipitates was investigated using a spark plasma sintering furnace under a range of processing conditions. Samples nominally containing 5 and 10wt% calcium-doped zirconia and hydroxyapatite made with Ca:P solution molar ratio 2.5 showed excellent thermal stability (investigated using in situ variable temperature X-ray diffraction) and were sintered via spark plasma sintering to >96% sintered densities at 1000°C resulting in hydroxyapatite and calcium-doped zirconia as the only two phases. Mechanical tests of spark plasma sintering sintered samples (containing 10wt% calcium-doped zirconia) revealed a three-pt flexural strength of 107.7MPa and Weibull modulus of 9.9. The complementary nature of the spark plasma sintering technique and continuous hydrothermal flow synthesis (which results in retention of a nanostructure even after sintering at elevated temperatures) was hence showcased. © The Author(s) 2012 Reprints and permissions.
AB - A rapid and continuous hydrothermal route for the synthesis of nano-sized hydroxyapatite rods co-precipitated with calcium-doped zirconia nanoparticles using a superheated water flow at 450°C and 24.1MPa as a crystallizing medium is described. Hydroxyapatite and calcium-doped zirconia phases in the powder mixtures could be clearly identified based on particle size and morphology under transmission electron microscopy. Retention of a nanostructure after sintering is crucial to load-bearing applications of hydroxyapatite-based ceramics. Therefore, rapid consolidation of the co-precipitates was investigated using a spark plasma sintering furnace under a range of processing conditions. Samples nominally containing 5 and 10wt% calcium-doped zirconia and hydroxyapatite made with Ca:P solution molar ratio 2.5 showed excellent thermal stability (investigated using in situ variable temperature X-ray diffraction) and were sintered via spark plasma sintering to >96% sintered densities at 1000°C resulting in hydroxyapatite and calcium-doped zirconia as the only two phases. Mechanical tests of spark plasma sintering sintered samples (containing 10wt% calcium-doped zirconia) revealed a three-pt flexural strength of 107.7MPa and Weibull modulus of 9.9. The complementary nature of the spark plasma sintering technique and continuous hydrothermal flow synthesis (which results in retention of a nanostructure even after sintering at elevated temperatures) was hence showcased. © The Author(s) 2012 Reprints and permissions.
KW - hydrothermal flow
KW - Hydroxyapatite
KW - nanostructure
KW - spark plasma sintering
KW - zirconia
KW - Co-precipitated
KW - Co-precipitates
KW - Elevated temperature
KW - Flow synthesis
KW - Hydrothermal routes
KW - In-situ
KW - Load-bearing
KW - Mechanical tests
KW - Molar ratio
KW - Nano-sized hydroxyapatite
KW - Particle size and morphologies
KW - Powder mixtures
KW - Processing condition
KW - Sintered density
KW - Sintered samples
KW - Spark plasma
KW - Superheated water
KW - Variable temperature
KW - Weibull modulus
KW - Zirconia nanoparticles
KW - Calcium
KW - Hydrothermal synthesis
KW - Nanostructures
KW - Phase stability
KW - Spark plasma sintering
KW - Transmission electron microscopy
KW - Weibull distribution
KW - X ray diffraction
KW - Zirconia
KW - hydroxyapatite
KW - nanoparticle
KW - zirconium
KW - zirconium oxide
KW - article
KW - chemistry
KW - particle size
KW - powder diffraction
KW - scanning electron microscopy
KW - transmission electron microscopy
KW - Durapatite
KW - Microscopy, Electron, Scanning
KW - Microscopy, Electron, Transmission
KW - Nanoparticles
KW - Particle Size
KW - Powder Diffraction
KW - Zirconium
U2 - 10.1177/0885328212444483
DO - 10.1177/0885328212444483
M3 - Journal article
VL - 27
SP - 79
EP - 90
JO - JOURNAL OF BIOMATERIALS APPLICATIONS
JF - JOURNAL OF BIOMATERIALS APPLICATIONS
SN - 0885-3282
IS - 1
ER -