Rheological Properties of HA Slurry for the Production of Bone Scaffolds by Layer Manufacturing
In recent years, innovative methods have been developed for the repair and regeneration of damaged and diseased bone tissue. Ceramic bio-scaffolds provide advantageous features as compared to other materials. The potential exists to use a slurry* composed of silica and hydroxyapatite (HA) which can be extruded through a controlled rate/pressure nozzle for rapid and accurate manufacturing of the green body of the scaffold. In order to fine-tune the slurry to be used in this process analysis of the HA particles and rheological characterisation and testing of a range of slurry formulations was undertaken. The measurement of the viscosity, its time dependent behaviour and the strength of the internal structure of the slurry are vital tools to characterize the suitability of ceramic slurry for the extrusion process. A plotting trial was also conducted with the objective of examining the behaviour of the different formulations under a range of pressure/extrusion rate parameters. The composition of the slurry formulations was in the range of 30 to 40 weight % of HA and was eventually fine-tuned to 35% by weight HA, which gave the best performance from the point of view of viscosity, oscillation, and extrusion properties. It was observed that the slurries behaved in non-Newtonian, shear-dependent complex modes.
Citation : Jones, J.B. et al. (2007) Rheological Properties of HA Slurry for the Production of Bone Scaffolds by Layer Manufacturing. 8th National Conference on Rapid Design, Prototyping and Manufacture, Ghent, Belgium,
Research Group : Additive Manufacturing Technology Group
Peer Reviewed : Yes