Production and bio-corrosion resistance of porous magnesium with hydroxyapatite coating for biomedical applications

Abstract

Biodegradable porous magnesium (Mg) with hydroxyapatite (HA) coating suitable for biomedical applications was fabricated. A blend of Mg and NaCl particles was sintered by spark plasma sintering (SPS), and then the NaCl was dissolved to obtain a porous structure. Different levels of porosity (50%, 60% and 70%) were achieved by adjusting the volume fraction of NaCl, while preserving high pore interconnectivity with a large pore size of similar to 240 pill. In addition, a dense HA coating layer comprised of needle-shaped HA crystals was formed on the surface of the porous Mg by treatment in an aqueous solution. Both bare and HA-coated porous Mg specimens with a porosity of 60% exhibited ductile behavior under compressive loading and similar levels of ultimate compressive strength (similar to 15 MPa). However, HA coating significantly enhanced the corrosion resistance of porous Mg. (C) 2013 Elsevier B.V. All rights reserved.