Mechanical strength of extrusion freeformed calcium phosphate filaments

  • H. Y. Yang
  • X. P. Chi
  • S. Yang
  • J. R. G. Evans


Hydroxyapatite–tricalcium phosphate mixtures of various compositions were extruded by a solid freeforming process to form lattice structures to serve as hard tissue scaffolds. The unwelded filaments, sintered at temperatures from 1100 to 1300°C, had radii from 115 to 135 μm and were tested in three point flexural loading using a purpose-built fixture. Flexural strength ranged from 20 to 100 MPa depending on composition and sintering temperature. Weibull moduli up to 13 were obtained. Compositions with 50% or more tri-calcium phosphate did not develop strengths much above 40 MPa and the strength of most compositions fell when the sintering temperature exceeded 1250°C. Multiple layer lattice structures were created and tested in compression.


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Copyright information

© Springer Science+Business Media, LLC 2010

Authors and Affiliations

  • H. Y. Yang
    • 1
  • X. P. Chi
    • 1
  • S. Yang
    • 1
  • J. R. G. Evans
    • 2
  1. 1.Department of Materials, Queen MaryUniversity of LondonLondonUK
  2. 2.Department of ChemistryUniversity College LondonLondonUK

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