Characteristic of Eggshell in Substitution of Hydroxyapatite in Biomedical Appliances

Hydroxyapatite (HAp) is one of the most versatile materials used for implantation purpose due to its similarity to natural bone material with a composition around 70% of our bone. Not only that, it is regarded as attractive biomedical materials because of their outstanding bioactivities and non toxicity. The purposes of this particular project are mainly to produce HAp powder by utilizing eggshell waste as its main raw material as well as to study the effectiveness of eggshell substitution in HAp on mechanical behaviour. The process involves drying and thermal decomposition of eggshell followed by hydrothermal reaction at low temperature with di-ammonium hydrogen phosphate and water. After that, the next process that takes place will involve compacting of the powder at pressure of 80 kg/cm2and sintering at temperature of 900-1300oC. Therefore, by using the suitable synthesizing method together with the workable sintering schedule for each synthesizing process, the optimized microstructure and properties of sintered HAp can be prepared.