Preparation and characterization of novel as-cast Ti-Mo-Nb alloys for biomedical applications

Abstract

Ti and its alloys are the most used metallic biomaterials devices due to their excellent combination of chemical and mechanical properties, biocompatibility, and non-toxicity to the human body. However, the current alloys available still have several issues, such as cytotoxicity of Al and V and high elastic modulus values, compared to human bone. β-type alloys, compared to α-type and (α + β)-type Ti alloys, have lower elastic modulus and higher mechanical strength. Then, new biomedical β-type alloys are being developed with non-cytotoxic alloying elements, such as Mo and Nb. Therefore, Ti-5Mo-xNb system alloys were prepared by argon arc melting. Chemical composition was evaluated by EDS analysis, and the density measurements were performed by Archimedes' method. The structure and microstructure of the alloys were obtained by X-ray diffraction and optical and scanning electron microscopy. Microhardness values were analyzed, and MTT and crystal violet tests were performed to assess their cytotoxicity. As the Nb concentration increases, the presence of the β-Ti phase also grows, with the Ti-5Mo-30Nb alloy presenting a single β-Ti phase. In contrast, the microhardness of the alloys decreases with the addition of Nb, except the Ti-5Mo-10Nb alloy, which has its microhardness increased probably due to the ω phase precipitation. Biological in-vitro tests showed that the alloys are not cytotoxic.

The bulk modulus of β-type Titanium Alloys for Hip and Bone Replacement

“…Notably, this value is lower than that of the commercial shape-memory alloy TNTZ-O, 88.7 GPa. The reason behind that is the presence of the β-Ti phase, adding a percentage of Mo a presenting a β-Ti phase which reduces the mechanical properties [20,21]. Depending on modeling, a set of experimental parameters can be used to characterize the powder neutron diffraction pattern.…”

Cytotoxicity of Commercially Pure Titanium (cpTi), Silver-Palladium (Ag-Pd), and Nickel-Chromium (Ni-Cr) Alloys Commonly Used in the Fabrication of Dental Prosthetic Restorations

“…This was explained by the formation of the TiO passive layer limiting the release of ions from titanium alloys [ 21 ]. Cardoso et al also found that pure titanium alloys used in combination with molybdenum (Mo) and niobium (Nb) elements showed no cytotoxicity effect as the result of cpTi alone [ 22 ].…”

Incorporation of Ca, P, Mg, and Zn Elements in Ti-30Nb-5Mo Alloy by Micro-Arc Oxidation for Biomedical Implant Applications: Surface Characterization, Cellular Growth, and Microorganisms’ Activity

“…The Ti-30Nb-5Mo alloy was produced by arc-melting in an argon-controlled atmosphere and in a water-cooled copper crucible. The details of the cast and bulk properties of this alloy can be found in previous works [35][36][37]. After melting, the produced ingots were hot rolled to reach a thickness of 1 mm, and cut to obtain square samples measuring 10 × 10 mm 2 .…”