1Department of Mechanical Engineering, University of Waterloo, Waterloo, Ontario, Canada
Bone is considered to be a composite material consisting of a high elastic modulus mineral ‘fibres’ embedded in a low elastic modulus organic matrix permeated with pores filled with liquids.
Properties and distribution of phases are established or estimated from the experimental data. Theories of composite materials are applied to bone with various contents of phases, and the discussion summarizes possible modes of deformation under load. Elastic behaviour is attributed to the joint properties of collagen and hydroxyapatite. Plastic deformation may occur in the amorphous portions of both mineral and organic phases. Visco-elastic characteristics are credited to the flow of liquids and viscous deformation of gels and sols.