The Modeling of Time Dependent Mechanical Properties of Cervine Enamel

Abstract

This work investigated the time dependent mechanical properties of cervine enamel. Three point bending tests were used to investigate mechanical properties of cervine enamel. The specimens of enamel were prepared from cervine incisors and the ramp-hold three point bending tests were performed to acquire the force-time and displacement-time relation of enamel specimens under three point bending load. The finite element analysis of specimen under three point bending load was performed by applying the three point bending ramp-hold displacement-time boundary condition to the plane strain finite element model of specimen and the reaction force of the loading tip was recorded. In this study, cervine enamel was considered as linear viscoelatic material. The long-term elastic modulus of enamel was evaluated from the stress and strain relations at the end of ramp-hold tests and the relaxation behaviour of enamel was estimated from the force-time and displacement time curves of three point bending ramp-hold tests. An inverse iterative finite element analysis procedure was developed to obtain the long-term elastic modulus, relaxation coefficients and characteristic times of linear viscoelastic model of cervine enamel. The results show that a linear viscoelastic model with two relaxation time constants can well describe the time dependent behaviour of cervine enamel.