Formation of tricalcium phosphate (TCP) in hydroxyapatite (HAp) - Based composites

Abstract

Limited natural resources demand the use of waste materials that can be processed for biomaterial applications. Hydroxyapatite (HAp) is a cow bone waste that has biocompatibility and osteoconductive properties. However, HAp has low mechanical properties so it is necessary to add materials such as titanium and aluminum to improve mechanical properties. The material was sintered using a self-propagating intermediate temperature synthesis (SIS) process by controlled combustion at high temperatures to produced composites for better mechanical properties. The experiment focused of the effect of titanium and temperature on the hardness and porosity-density values on the sample. Preceded by a simulation to measure the effect of heat on the success of composite formation. The results showed that the highest hardness value and the lowest porosity value were found in the 20% titanium sample at a temperature of 850 °C with a value hardness of 44.79 HV and 22.63% porosity. This happens because at a temperature of 850 °C a reaction occurs between HAp and titanium to form CaTiO3 so that the composite hardness increases. While the value of porosity decreased at this temperature due to the fusion of the grains so that the pores are closed. Based on the results of the study, the characteristics of HAp composites with 20% titanium content at a temperature of 850 °C, were also traced using finite element simulations to predict the ideal operating temperature at the selected temperature variation.