Calcium Orthophosphates as Bioceramics - Calcium Orthophosphates: Applications in Nature, Biology and Medicine - page 419

303. The nature of flaws in most ceramics is statistical. As such, the strength
of ceramics is not one specific value, but a distribution of strengths.
The Weibull modulus is a measure of the distribution of flaws,
usually for a brittle material. The modulus is a dimensionless number
corresponding to the variability in measured strength and reflects the
distribution of flaws in the material.
304. Suzuki, S., Sakamura, M., Ichiyanagi, M., and Ozawa, M. (2004) Internal
friction of hydroxyapatite and fluorapatite, , 625-627.

305. Strength can be defined as the maximum tensile stresses that a
material can endure before fracture occurs. It might also be defined
as force per unit area required to initiate and propagate a crack to the
fracture point [194].
306. In materials science, fatigue is the progressive and localized structural
damage that occurs when a material is subjected to cyclic loading.
307. le Huec, J. C., Schaeverbeke, T., Clement, D., Faber, J., and le Rebeller,
A. (1995) Influence of porosity on the mechanical resistance of
hydroxyapatite ceramics under compressive stress,

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308. Hsu, Y. H., Turner, I. G., and Miles, A. W. (2009) Mechanical properties
of three different compositions of calcium phosphate bioceramic
following immersion in Ringer's solution and distilled water, J. Mater.

, 2367-2374.
309. The elastic modulus is the ratio of stress to strain below the
proportional limit. It represents the magnitude of the interatomic
stiffness of a material within the elastic range when tensile or
compressive forces are applied. It is also an indication of the amount
of reversible deformation that will occur in a structure when a load is
applied [194].
310. de Aza, P. N., de Aza, A. H, and de Aza, S. (2005) Crystalline bioceramic
materials,

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311. Ching, W. Y., Rulis, P., and Misra, A. (2009)

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312. Hardness of a material usually is considered as a measure of the
resistance to permanent indentation. A standardized force or weight is
applied to an indenter pressing into the surface of a material to create
a symmetrical shaped indentation [194].
313. Poisson's ratio (ν), named after Siméon Poisson, is the ratio, when
a sample object is stretched, of the contraction or transverse strain