Abstract
Super fast densification behavior and the attendant corrosion features of magnesium/hydroxyapatite (Mg/HAp) bio-nanocomposites processed by high frequency induction heat sintering (HFIHS) were investigated in order to develop a new biodegradable hard tissue substituent. Mg/HAp nanocomposite with various HAp contents (0-5 wt %) were prepared using pure magnesium and HAp nanopowder as raw materials. In order to investigate the corrosion behavior of Mg/HAp in vitro, the composite samples were immersed in a simulated body fluid (SBF) at 37 degrees C. The electrochemical tests were conducted under the same condition. The results indicated that the presence of HAp and the increase of its content decreased the dissolution of Mg and improve the resistance of magnesium against uniform corrosion, while increase the probability of the occurrence of localized corrosion. The best performance against corrosion in SBF solution was obtained for Mg/5.0wt%HAp. The EIS experiments were carried out to determine kinetic parameters for electron transfer reactions at the electrode/electrolyte interface magnesium in SBF solution. The values of resistances, R-S, R-P1, R-P2 and R-P3 increased in the presence of HAp and the increase of its content from 1wt% to 5 wt%. This effect also decreased the values of the C-dl1, CPE, and C-dl2 and indicates that HAp particles improve the corrosion resistance of magnesium in SBF solution and its effect increases with increasing HAp concentration. The impedance of the interface (vertical bar Z vertical bar) of Mg increased in the presence and by the increase of HAp. In this work, the Mg/1 to 3 wt% HAp composite was of the optimal mechanical properties and corrosion resistance.