Numerical simulation of mechanical behaviors of degradable porous bioceramics with cracks

Abstract

Hydroxyapatite bioceramics is simulated by using finite element method (FEM). The influences of porosity, hole shape, angle of crack and other parameters on the ceramics are analyzed. The results show that with the increase of the angle between crack and horizontal direction, the stress intensity factor K _I decreases gradually, but stress intensity factor K _II increases at first and then it decreases. The value of K _II reaches maximum when the angle between crack and horizontal direction is 45°. K _I and K _II rise with the increase of porosity, and they are almost the same for the circular and hexagonal holes. For elliptical holes, K _I and K _II reach maximum when the long axis of ellipse is perpendicular to the loading direction and they reach minimum when the same axis is parallel to the loading direction. Moreover, with the increase of the angle between the long axis and loading direction, K _I and K _II increase gradually.

Keywords

porous bioceramics / degradation / finite element method (FEM) / porosity / stress intensity factor

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