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An investigation of the technical aspects of producing sufficiently high strength porous biocompatible medical implants and tissue scaffolds from nitinol or pure titanium using selective laser sintering/melting (SLS/M) is presented. In particular, the necessary processing parameters and procedures for successful laser synthesis of functionally graded implants have been established. Physical and mechanical properties, microstructure, corrosion behavior of the synthesized structures, as well as shape memory in porous layered nitinol structures made using laser synthesis are reported. Comparative morphological and histological results of SLS of porous titanium and nitinol made implants are also presented. Investigations were carried out on primary cultures of dermal fibroblasts and mesenchymal stromal human cells. The possibility of cultivating bone marrow on the porous carrier-incubator made from NiTi and pure titanium in vitro was determined. Sufficient understanding of the nature of laser synthesized titanium and nitinol structures was developed in order to determine their suitability for use as functional implants. This resulted in superior tissue to implant fixation and the development of minimally invasive surgical procedures. [ABSTRACT FROM AUTHOR]

The interaction of sintered hematite Fe2O3 with melts in the PbO–SiO2 system at 900°C and melts in the Na2O–SiO2 system at 1150°C is investigated by the annealing–quenching technique with the use of standard physicochemical methods (X-ray powder diffraction analysis, scanning electron microscopy, quantitative X-ray microprobe analysis). The melting diagrams of the PbO–Fe2O3–SiO2 and Na2O–Fe2O3–SiO2 systems are calculated and constructed on the basis of the model of regular solutions. An analysis of the experimental and calculated data demonstrates that the diffusion dissolution of hematite at the “hematite–melt” heterogeneous interface can be observed only for the PbO melt. For lead and sodium silicate melts, the diffusion process is accompanied by the concurrent redox reaction with the liberation of gaseous oxygen, which appreciably promotes the erosion of solid hematite. [ABSTRACT FROM AUTHOR]