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Abstract Zinc was recently suggested to be a potential candidate material for degradable coronary artery stent. The corrosion behavior of pure zinc exposed to r-SBF up to 336 h was investigated by electrochemical measurements and immersion tests. The morphology and chemical composites of the corrosion products were investigated by scanning electron microscope, grazing-incidence X-ray diffraction, X-ray photoelectron spectroscopy and Fourier transform infrared spectrometer. The results demonstrate that the initial corrosion products on the pure zinc mainly consist of zinc oxide/hydroxide and zinc/calcium phosphate compounds. The pure Zn encounters uniform corrosion with an estimated corrosion rate of 0.02–0.07 mm y−1 during the immersion, which suggests the suitability of pure Zn for biomedical applications. [ABSTRACT FROM AUTHOR]

Fatigue behaviors of a biocompatible Ni-free Zr60.14Cu22.31Fe4.85Al9.7Ag3 Zr-based bulk metallic glass (BMG) have been studied under three-point-bending test in a simulated body fluid (SBF) at 37 °C and compared with those in air at room temperature (RT). The BMG shows a high fatigue limit of approximately 366 MPa in SBF, which was slightly lower than that in air (400 MPa). The fatigue cracks tended to initiate from the defects such as cast-pores, inclusions and corners of the samples and propagate in a similar path in SBF and in air. Three distinct regions, i.e. a crack-initiation region, a stable crack-growth region and an unstable fast-fracture region were clearly observed on the fatigue-fractured surface. Although pitting occurred at the defects where crack initiated, it does not affect significantly the fatigue life of the BMG, because the lifetime in the present BMG is mainly determined by crack propagation. The high corrosion-fatigue limit of the studied BMG results from its excellent corrosion resistance in SBF and intrinsically good toughness. [ABSTRACT FROM AUTHOR]

The in-vitro biological behavior of a newly-developed iron-containing hydroxyapatite/titanium (HA/Ti) composite was investigated by immersing the composites in the simulated body fluid (SBF) for up to 5 weeks. The addition of iron was observed to have a significant influence on the in-vitro biological behavior of the composites. The obtained results revealed that the stability of the composites in the physiological solution was markedly improved. The solubility decreased in the order of pure HA, HA/5%(Ti-33%Fe), and HA/15%(Ti-33%Fe). Precipitation occurred on the surface of HA/5%(Ti-33%Fe) composite, showing a good combination of physiostability with bioactivity, while HA/15%(Ti-33%Fe) composite exhibited superior physiostability since there was no obvious change on the surface of HA/15%(Ti-33%Fe). [Copyright &y& Elsevier]