THE PREDICTION OF FRACTURE TOUGHNESS PROPERTIES OF BIOCERAMIC MATERIALS BY CRACK GROWTH SIMULATION USING FINITE ELEMENT METHOD AND MORPHOLOGICAL ANALYSIS

Abstract

Various types of hydroxyapatite (HA) structures have received great attention of scientific researcher in biomaterials field. Also, it is common that HA is the essential inorganic materials in human hard tissue such as bone or teeth. Fracture toughness and micro-hardness properties are the important parameters required for the prediction of the mechanical performance of biomaterials structures before failures. The indentation micro-fracture method, which yields for the mode is critical stress intensity factor, K-IC, is particularly useful when applied to brittle materials with low KIC. As fracture toughness is easy, fast technique and needs small testing equipments and area, here we represent the enhancement in hardness and toughness which is possible due to attain nano-crystalline size for HA powder using in powder, bulk or coating form, suitable sintering and variable composition. It is obvious that the HA hardness have close relationship with fracture toughness. Also, materials properties as the size of grain changes/reduced from micron to nano-meters influence the mechanical behaviour of biomaterials. As the current observation of papers illustrates, the HA toughness rise up to about 70% with compositing with other beneficial additives like Al2O3, polyethylene, fluorine, diopside, zircon, akermanite, bioglass (BG), tungsten carbide (WC), carbon nanotube (NC), etc. Secondly, sintering improve the fracture toughness of the HA particles and other biomaterials as well. Also, one can say that sintering procedure effect the microstructure mechanisms for simultaneous enhancements in the hardness and fracture toughness of the bio-ceramics. In the current paper we predict the fracture toughness value changes to greater value with the morphology of the powder less in the case of amorphous materials like zircon. We consider the prediction method with Finite element analysis and gather data from other literatures.