Finite element analysis and experiment study on the elastic properties of randomly and controllably distributed carbon fiber-reinforced hydroxyapatite composites

Abstract

Randomly distributed carbon fiber-reinforced hydroxyapatite (RCF/HA) and controllably distributed carbon fiber-reinforced hydroxyapatite (CCF/HA) composites were firstly studied to design and prepare different required composite artificial bones with satisfying mechanical properties by combining experiment approach, theoretical prediction and finite element analysis (FEA). A plug-in was obtained by secondary development of ABAQUS for the FEA. A 3D representative volume element (RVE) for RCF/HA and CCF/HA can be easily generated using this tool. Stress and strain analyses of three directions of RVE were performed by ABAQUS with different fiber mass fractions and distributions. The elastic modulus of CF/HA composites were obtained. With 0.2 wt% fiber, the elastic modulus of RCF/HA and CCF/HA composites increased by 6.31% and 54.4% compared with that of HA, respectively. For CCF/HA composites, the elastic modulus increased significantly with the increasing fiber mass fraction in the E11 of the fiber. The results of experiment study and theoretical prediction were consistent with that of FEA. The maximum error between the FEA and experiment study was 2.84%, which confirmed that the RVE model was rational and accurate. The results indicated the fiber distribution can greatly affect the elastic modulus of the composites. In the future study, the controllably distributed fiber–reinforced composites would be a good choice because they can improve the mechanical properties as required. This study would endow possibility of designing and preparing the CF/HA bio-ceramics with satisfied mechanical properties by FEA and proper preparation parameter. It would also speed up application of clinical practice for CF/HA composites.