Sintering effects on the strength of hydroxyapatite

doi:10.1016/0142-9612(95)98859-C

Biomaterials

Volume 16, Issue 5, 1995, Pages 409-415

https://doi.org/10.1016/0142-9612(95)98859-C Get rights and content

Abstract

Mechanisms underlying temperature-strength interrelations for dense (> 95% dense, pores closed) hydroxyapatite (HAp) were investigated by comparative assessment of temperature effects on tensile strength, Weibull modulus, apparent density, decomposition (HAp:tricalcium phosphate ratio), dehydroxylation and microstructure. Significant dehydroxylation occurred above ~800 °C. Strength peaked at ~80 MPa just before the attainment of closed porosity (~95% dense). For higher temperatures (closed porosity), the strength dropped sharply to ~60 MPa due to the closure of dehydroxylation pathways, and then stabilized at ~60 MPa. At very high temperatures (> 1350 °C), the strength dropped catastrophically to ~10 MPa corresponding to the decomposition of HAp to tricalcium phosphate and the associated sudden release of the remaining bonded water.

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Biomaterials

Abstract

References (21)

The production and characterisation of a hydroxyapatite ceramic material

Calcium phosphate ceramic coatings on porous titanium: effect of structure and composition on electrophoretic deposition, vacuum sintering, and in vitro dissolution

Biomaterials

The structure and biomechanics of bone

A study into the preparation of dense hydroxyapatite ceramics using powders of different morphologies

Optimisation of toughness in dense hydroxyapatite ceramics

Mechanical evaluation of hot isostatically pressed hydroxylapatite

Interceram

Bioceramics: from concept to clinic

J Am Ceram Soc

Preparation and sintering of hydroxyapatite ceramics

Effect of chemical composition on the mechanical strength of sintered apatite

Nagoya Kogyo Gijutsu Shikensho Hokoku

Cited by (305)

Dissolution-precipitation synthesis and cold sintering of mussel shells-derived hydroxyapatite and hydroxyapatite/chitosan composites for bone tissue engineering

Properties of sintered zinc hydroxyapatite bioceramic prepared using waste chicken eggshells as calcium precursor

Characterization of hydroxyapatite powders and selective laser sintering of its composite with polyamide

3D porous HA/TCP composite scaffolds for bone tissue engineering

Effects of poloxamer additives on strength, injectability, and shape stability of beta-tricalcium phosphate cement modified using ball-milling

Freeze casting of hydroxyapatite-titania composites for bone substitutes