L-PBF processing and characterization of a Ti35Nb30Zr29Mo3Ta3 multiprincipal element alloy for medical implants

Abstract

This Letter reports on the processing, mechanical properties, electrochemical performance, and toxicity behavior of a multiprincipal element Ti35Nb30Zr29Mo3Ta3 alloy. The recovered centimeter-sized cubes or parallelepipeds were polished before analysis. It was found that the homogeneity and yield stress of the alloys get increased when higher volumetric energy densities are applied during processing. The synthesized alloys also exhibited a Young modulus closer to those of bones than those usually reported on the conventional orthopedic metals (60–80 GPa for this alloy against 110 and 4–30 GPa for the Ti-6Al-4V and bone, respectively). The electrochemical corrosion assays performed at 25 and 37 °C, in sodium chloride (NaCl, 0.1 M), deoxygenated high glucose Dulbecco's Modified Eagle Medium (DMEM), and deoxygenated DMEM implemented with fetal bovine serum showed corrosion potentials (Ecorr) ranged in the order NaCl(25 °C) ≈ DMEM + PBS(37 °C) > DMEM(37 °C) and impedances much larger in the DMEM and DMEM + PBS media than in NaCl. Finally, pre-osteoblasts cells cultured in the medium conditioned by the alloy did not evidence cytotoxicity effect, because no effects on the cell proliferation and morphology were observed. These data suggest the biocompatibility of this alloy, indicating no acute toxicity, which is a prerequisite for the integration of an alloy as a bioimplant.