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Updated: May 24, 2026

Rapid Mix Preparation of Bioinspired Nanoscale Hydroxyapatite for Biomedical Applications
Published on: February 23, 2017
Part I: porosity dependence of the Weibull modulus for hydroxyapatite and other brittle materials
1Chemical Engineering and Materials Science Department, Michigan State University, East Lansing, MI 48824, United States.
Abstract:
Porous brittle materials are used as filters, catalyst supports, solid oxide fuel cells and biomedical materials. However the literature on the Weibull modulus, m, versus volume fraction porosity, P, is extremely limited despite the importance of m as a gauge of mechanical reliability. In Part I of this study, m is determined for 441 sintered hydroxyapatite (HA) specimens fractured in biaxial flexure for 0.08 ≤ P ≤ 0.62. In this study, we analyze a combined data set collected from the literature that represents work from a total of 17 different research groups (including the present authors), eight different materials and more than 1560 oxide and non-oxide specimens, the m versus P plot is "U-shaped" with a wide band of m values for P<0.1 (Region I) and P>0.55 (Region III), and a narrower band of m values in the intermediate porosity region of 0.1
, and the Young's modulus E for the HA specimens tested in Part I along with literature data for other brittle materials. Both <σ(f)> and E are power law functions of the degree of densification, ϕ, where ϕ=1-P/P(G) and P(G) is the green (unfired) porosity.
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