Corrosion properties in a simulated body fluid of Mg/β-TCP composites prepared by powder metallurgy

Abstract

Magnesium matrix composites (MMC) reinforced with 5wt% tricalcium phosphate (TCP) particles were prepared by powder metallurgy. Pure magnesium (CP-Mg) was fabricated by the same procedure for comparison. Scanning electron microscopy and energy- dispersive X-ray spectroscopy analyses revealed that TCP particles were distributed homogeneously in the MMC. In order to investigate the corrosion properties, MMC samples were immersed in a simulated body fluid (SBF) at 310±0.5 K for 72 h. The mass loss of the samples in SBF and the pH values of the SBF were evaluated. Moreover, electrochemical measurements were conducted in the SBF. It was shown that the corrosion rate of the MMC decreased with the addition of TCP compared with CP-Mg. Hydroxyapatite was formed on the surface of MMC samples after immersion in the SBF for 72 h but not on the surface of CP-Mg.

Keywords

metallic matrix composites / powder technology / corrosion / hydroxyapatite / magnesium

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