Biocompatibility of Porous SHS-TiNi

Abstract

Implants made of porous SHS-TiNi alloys are successfully used in medicine to replace solid tissues of the human body. Self-propagating synthesis reaction of TiNi alloy was carried out through layer-by-layer combustion. XRD analysis of the phase composition and structural parameters of porous Ni50Ti50 alloy, as well as microscopic studies, were carried out. The structural methods employed in the study showed that the surface of porous SHS-TiNi alloys is a complex of dense layers of amorphous-nanocrystalline intermetallic oxycarbonitrides saturated with O, N, C intercalation impurities. The study of the surface layer S showed that the layer S consists of three layers: the foam layer F and two sublayers. Samples were studied for the nonuniform potential distribution in the cross section of interpore partitions. It was shown that they correlate with the structural phase inhomogeneity of the SHS-TiNi alloy. The structural studies carried out using different methods allowed us to reliably establish the presence of surface nonmetallic phases in the form of surface films and grain boundary inclusions formed during the self-propagating reaction synthesis of the porous TiNi alloy. High biochemical compatibility is ensured by specific surface layers of the porous alloy formed in the process of its metallurgy, which do not require additional surface modification.