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The electrical resistance sintering is a fast method to fabricate metallic samples in the field of metallurgy and it was used to obtain the Ti-Nb-Sn alloy to be applied as biomaterial, variyng different electrical current densities (11, 12 and 13 kA). The powders were obtained by mechanical alloying, then they were compacted at pressure of 193 MPa during 700 ms. The structure and microstructure of the powders and the samples was evaluated by x-ray diffraction, by Field Emission Scanning Electron Microscopy and electron back-scattered diffraction. The mechanical properties were evaluated by microhardness assay and corrosion resistance was made in Ringer Hartmann’s solution at 37ºC. The samples are formed by α, α” and phase β. The % of phase β in the samples obtained at 11, 12 and 13 kA was 96.56, 98.12 and 98.02 respectively. The peripheral zone present more presence of microporosity than the central zone. The microstructure is also formed by bcc-β grains equiaxial, and the samples obtained at 12 kA present better homogeneity of the microstructure. The grain size increased with the increase of the electrical current density. The microhardness are in the range of 389-418 HV and decreased with the increase of electrical current density. Corrosion tests proved excellent corrosion resistance of the alloys (0.24-0.45 µA/cm2). The standard deviation of kinetic parameters of the samples at 11 and 13 kA were very higher, related to the lack of homogeneity of the microstructure.

The influence of open vessels during milling for 12, 24, 40 and 60 h on microstructure homogeneity and oxygen content effect in the β Ti–Nb–Mo system microstructure were studied. The β phase increased with longer milling times and the strain hardening on particles was verified at 60 h when agglomeration was greater and was also noticed after 40 h in the continuous mode. Oxygen content dropped slightly until 40 h and increased after 60 h, a result linked with the observed hardening. For 40 h in the continuous mode, the oxygen content was noted near 12 h, 24 h and 40 h with high hardness values. For the sintered parts, the α phase and oxygen content significantly increased in all samples. Microhardness-sintered samples decreased compared to sample powders due to grain growth during the sintering. Bending strength was higher at 60 h with more oxygen and α phase content. After 40 h in the continuous mode, more suitable mechanical properties were reached because hardness and bending strength were closer to bone tissue, which was associated with strain hardening and a small crystallite size.