Statistical evaluation of nano-structured hydroxyapatite mechanical characteristics by employing the Vickers indentation technique

In this study, the mechanical characteristics of hydroxyapatite (HA) against the Vickers indenter under different loads were investigated. For this purpose, the HA powders were first synthesized by a one-pot solvothermal method. The powders were then subjected to consolidating by the spark plasma sintering (SPS) method for mechanical evaluation. Characterization methods used in this study included X-rays diffraction, field emission scanning electron microscopy, transmission electron microscopy, inductively coupled plasma, energy dispersive X-ray spectroscopy, and Vickers indentation technique. The findings of this study showed that the morphology of the synthesized powders by solvothermal method were rod-shaped and nanometer-sized. As the applied load increased to 2 N, the elastic modulus increased but the hardness did not change much. At a constant force, the contact depth increased with decreasing elastic modulus and hardness. Also, increasing contact depth increased the stiffness and contact area. The results of this study will be useful for investigating the mechanical properties of HA based materials.