Synthesis and Characterization of NiTiMDAg Nanocomposites for Orthopedic Applications

Several calcium-based compounds are used to reinforce NiTi composite, but their porous structure and high ceramic content degrade its mechanical characteristics. Therefore, the work aimed to combine reinforcement of NiTi composite using marble dust and nano-silver. The NiTiMDAg nanocomposites were successfully synthesized by the powder metallurgy process. A dense and smooth surface with a relative density of 94.93% was achieved for NiTiMD6Ag6 nanocomposite due to the effective interlocking and bonding provided by nano-silver. The XRD shows the formation of NiTi phase (B19 ' and B2) and many other phases (i.e., Ni2Ti, Ni3Ti, Ni4Ti3, NiTi2 and NiTiO3). The combined reinforcement (i.e., marble dust and silver) enhances elastic modulus and strength of NiTiMDAg nanocomposite up to 5.63 GPa and 112.48 MPa, respectively. The results show that the Ni release reduced to 4.00 mg.l(-1).cm(2) and a uniform apatite formed on the NiTiMDAg nanocomposites.