The Effect of Sonication Duration on the Characteristics of Nano Hydroxyapatite-Silica (nHAp/SiO₂) Composite and its Mechanical Properties

In this present study, we report the fabrication of nano-hydroxyapatite/silica (nHAp/SiO₂) composite with the sonochemical method from Bojonegoro natural minerals, i.e. onyx stone and quartz sand. The nano-HAp was synthesized from Ca (OH)₂ and H₃PO₄ solutions. The nHAp was successfully composed with silica by using sonication role. The sonication process was done in 1, 2, 3, and 4-hour variations at 20 % wt filler composition of Silica. The crystal structure properties of nHA were evaluated by X-ray diffraction (XRD). The ratio of Ca/P was evaluated by scanning electron microscopy and energy dispersive X-ray spectroscopy (SEM-EDX). The microstructural characterization of the sample was captured by scanning electron microscopy (SEM). Vickers hardness test was also conducted to identify the hardness (mechanical properties) of the sample. On the other hand, the porosity of the sample also was reported. The results of this study show that hydroxyapatite has a size of 30.57 nm and the ratio of Ca/P was 1.57. The variations of sonication affect the mechanical properties of nHA-SiO₂ composite. The increasing sonication duration influences the hardness properties and porosity. The porosity of HAp (31.58 %) is still suitable to be applied for biomedical applications.