PRODUCTION AND CHARACTERIZATION OF Ti COMPOSITES REINFORCED WITH NbC BY NON-CONVENTIONAL TECHNIQUES OF MANUFACTURING
Production of composite materials using non-conventional methods, such as severe plastic deformation (SPD) and spark plasma sintering, has attracting much attention of scientists over the last years. In this study, equal channel angular pressing (ECAP), which is the more developed technique of severe plastic deformation, is investigated to manufacture high resistance materials with potential for structural and biomedical applications. Composite samples were also manufactured by SPS, allowing comparing the effectiveness of both techniques (ECAP and SPS) to produce densely consolidated composite parts. Therefore, it is possible to evaluate ECAP processing as an alternative for sintering techniques such as SPS, generally employed to produce metal matrix composites. Ti composites reinforced with NbC produced by ECAP and SPS were investigated. The effects of processing parameters on the densification, mechanical and tribological properties were investigated. The microstructure of the samples was analyzed by confocal scanning laser microscopy, scanning electron microscopy and X-ray diffraction. Mechanical and tribological properties were assessed by microhardness, nanoindentation and wear tests. The microhardness of SPS produced samples were higher than those of ECAP processed samples. In the case of SPS, different powder pre-processing conditions were also tested. The values of elastic modulus for the ECAP processed composites were close of the desirable values for biomedical implants.