TY - JOUR
T1 - Spark plasma extrusion of binder free hydroxyapatite powder
AU - Diaz-De-la-torre, Sebastian
AU - Munoz-Juarez, Isaac
AU - Mendez-Garcia, Jose C.
AU - Gonzalez-Corral, Gisela
AU - Casas-Luna, Mariano
AU - Montufar, Edgar B.
AU - Oliver-Urrutia, Carolina
AU - Pina-Barba, Maria Cristina
AU - Celko, Ladislav
N1 - Publisher Copyright:
© 2022 Sebastián Díaz-de-la-Torre et al., published by De Gruyter.
PY - 2022/1/1
Y1 - 2022/1/1
N2 - This work explores the possibility of manufacturing dense and nanocrystalline hydroxyapatite (HA) large monoliths by spark plasma extrusion (SPE). This method combines uniaxial mechanical compression, high temperature, and electromagnetic field to promote the extrusion and sintering of HA powder in one single step. The results show that the binder-free extrusion of pre-compacted HA powder is feasible at a temperature similar to the temperature at which nanocrystalline HA shows superplastic behavior. The extrusion continues throughout the sliding and rotation of the particles, and also due to the grain boundary sliding, up to the point where no more material is available, thus producing monoliths of nearly 30 mm in length and 10 mm in diameter. The dehydration and smooth surface of the powder appear as paramount factors to facilitate the HA extrusion without additives. The extruded HA preserved the stoichiometry and nanometric grain size and exhibited preferential microstructural alignment in the direction of extrusion. The material experiences local thermal and pressure gradients during extrusion, producing different densification and hardness along its length. The SPE of HA will benefit the healthcare field by offering new processing approaches of bone substitutes and osteosynthesis devices.
AB - This work explores the possibility of manufacturing dense and nanocrystalline hydroxyapatite (HA) large monoliths by spark plasma extrusion (SPE). This method combines uniaxial mechanical compression, high temperature, and electromagnetic field to promote the extrusion and sintering of HA powder in one single step. The results show that the binder-free extrusion of pre-compacted HA powder is feasible at a temperature similar to the temperature at which nanocrystalline HA shows superplastic behavior. The extrusion continues throughout the sliding and rotation of the particles, and also due to the grain boundary sliding, up to the point where no more material is available, thus producing monoliths of nearly 30 mm in length and 10 mm in diameter. The dehydration and smooth surface of the powder appear as paramount factors to facilitate the HA extrusion without additives. The extruded HA preserved the stoichiometry and nanometric grain size and exhibited preferential microstructural alignment in the direction of extrusion. The material experiences local thermal and pressure gradients during extrusion, producing different densification and hardness along its length. The SPE of HA will benefit the healthcare field by offering new processing approaches of bone substitutes and osteosynthesis devices.
KW - grain boundary sliding
KW - hydroxyapatite
KW - nanocrystalline
KW - sintering
KW - spark plasma extrusion
KW - spark plasma sintering
KW - superplasticity
UR - http://www.scopus.com/inward/record.url?scp=85133688095&partnerID=8YFLogxK
U2 - 10.1515/ntrev-2022-0131
DO - 10.1515/ntrev-2022-0131
M3 - Artículo
AN - SCOPUS:85133688095
SN - 2191-9089
VL - 11
SP - 2295
EP - 2303
JO - Nanotechnology Reviews
JF - Nanotechnology Reviews
IS - 1
ER -