Microstructure and mechanical properties of binary Ti-Nb alloys for application in medicine

An application of differential injection to fabricate functionally graded Ti-Nb alloys using DED-CLAD® process

“…The microhardness of the Ti-44Nb alloy using pre-alloyed powder and differential injection were 212 ± 5 HV and 228 ± 14 HV, respectively. These results are quite similar in both cases and are in accordance with value reported in the literature, i.e., 210 HV for Ti-40Nb (as-melt alloy) (Thoemmes et al, 2016).…”

“…When niobium content was in the range of 0-25%, the microhardness increased to 258 ± 36 HV. This increase in the microhardness was explained by some authors by the presence of a small fraction of ω-phase (Lee et al, 2002;Thoemmes et al, 2016). As the DED-CLAD ® process consists in manufacturing parts layer by layer, each layer experiences remelting.…”

“…Despite the authors have presented the process parameters, the evolution of the chemical composition as well as the microhardness, no information are given about the crystallographic orientation, the mechanical properties such as the elastic modulus or the presence of unmelted particles (Cheung, 2015). Outside of this study, the maximum Nb content studied in the literature for binary Ti-Nb functionally graded alloys is 50% (Thoemmes et al, 2016).…”

“…In sample n°1, the Nb content varied from 5% Nb, 10% Nb, 40% Nb, 70% Nb, 100% Nb, and in sample n°2 the Nb content varied from 0% Nb, 25% Nb, 50% Nb, 75% Nb, 100% Nb. These compositions have been chosen in case of sample n°1 to compare the microstructural and mechanical properties with the binary alloys ever studied in the literature (Lee et al, 2002;Thoemmes et al, 2016;Wang et al, 2017) and in the case of sample n°2 to compare with another alloy such as Ti64-Mo (Schneider-Maunoury et al, 2017) and thus observe the behaviour difference depending on the alloy element. Each sample consisted of a single-track width sample with five gradients of the chemical composition with at least four layers deposited in order not to suppress the dilution effect between adjacent layers.…”

On the Use of Functionally Graded Materials to Differentiate the Effects of Surface Severe Plastic Deformation, Roughness and Chemical Composition on Cell Proliferation

“…For the polished sample, the maximum hardness was reached for 25% of Nb (Figure 4a). According to the literature [42,43], this increase is due to the presence of a small fraction of ω-phase, especially when the composition is around 25% Nb. The amount of omega phase was increased by the successive remelting and tempering from the successive layer by layer deposition generated by the DED-CLAD process.…”