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This article presents the effect of an Indirect Plasma Nitriding process on the microstructure and properties of Titanium Grade- 2 samples manufactured by Direct Metal Laser Sintering Method (DMLS). It was determined, based on morphological analysis that the physical and chemical phenomena occurring at the surface during nitriding has a decisive effect on surface roughening. Phase and stress analysis shown the nitrided layer produced in a pure nitrogen at 760 °C and containing TiN + TiN0.30+ Ti2N is under compressive stress and its characteristic of a high hardness and Young Modulus as compare to Grade 2 titanium samples produced only by DMLS technique (without nitriding). Static tensile stress carried out at room temperature show that the nitrided samples containing TiN + TiN0.30+ Ti2N have much lower yield (YS0.2) and tensile strength (UTS) compared to the not nitrided samples. Tests carried out in Ringer’s solution, using impedance and potentiodynamic methods at temperatures elevated to 36.6 ± 0.3 °C to simulate human-’s’ body temperature, show that nitriding increased corrosion resistance of the alloy.

This article describes the manufacturing of silicon carbide composites with the addition of quasi-two-dimensional titanium carbide Ti3C2, known as MXene. The composites were obtained by the powder metallurgy technique, consolidated with the use of the Spark Plasma Sintering method at 1900 °C and dwelled for 30 min. The influence of the Ti3C2MXene addition on the microstructure and mechanical properties of the composites was investigated. The structure of the MXene phase after the sintering process was also analyzed. The results showed a significant increase (almost 50%) of fracture toughness for composites with the addition of 0.2 wt% Ti3C2MXene. In turn, the highest hardness, 23.2 GPa, was noted for the composite with the addition of the 1.5 wt% Ti3C2 MXene phase. This was an increase of over 10% in comparison to the reference sample. The analysis of chemical composition and observations using a transmission electron microscope showed that the Ti3C2 MXene phase oxidizes during sintering, resulting in the formation of crystalline, highly defected, disordered graphite structures. The presence of these structures in the microstructure, similarly to graphene, significantly affects the hardness and fracture toughness of silicon carbide.