The bioactivity behavior of Magnesium Alloys (AZ91) reinforced with HAP (composite) used for biomedical applications

Abstract

The aim of this research is to evaluate the effect of hydroxyapatite (HAP) particles content on bioactivity behavior of a composite AZ91/HAP. Novel AZ91 with (0, 3 wt%, 6wt% and 9wt% of HAP) composites were fabricated using a blend-press-sinter powder metallurgy (PM) method. The mixture were mxed for 30 minutes at 160 rpm before compacted at 500MPa for 2 minutes. Composite samples were sintered at 400°C for 1.5 hours before proceed to immersion test. The bioactivity behavior of Mg alloy (AZ91) and Mg alloy (AZ91/HAP) composites will be analyzed by pH analysis after immersion in Simulated Body Fluid (SBF) for 3 days. Meanwhile to study the surface morphology and phase composition of the composites, Scanning Electron Microscope (SEM) and X-ray Diffraction (XRD) analysis were conducted. Mechanical properties of the samples were studied by Vickers Hardness test. Formation of apatite layer was analyzed by EDX and XRD after immersion test in Simulated Body Fluid (SBF). The highest micro-hardness value and pH value of the composites were 55.1 HV and 10.3 pH. Optimum addition of HAP to Mg alloys that suit with biomedical application is 3wt% because this AZ91/3wt% of HAP shows good mechanic properties and good bioactivity behavior.