Mechanical properties and microstructural evolution of vacuum hot-pressed titanium and Ti–6Al–7Nb alloy

Abstract

Mechanical properties and microstructural evolution of vacuum hot-pressed titanium and Ti-6Al-7Nb alloy, Journal of the Mechanical Behavior of Biomedical Materials, May 2012, v. 9, p. 91-99, doi: http://dx.doi.org/10.1016/j.jmbbm.2012.01.015 © Elsevier 2012Graphical Abstract > Hot-pressing is used to make almost fully dense titanium and Ti-6Al-7Nb alloy. > Study of the bending properties of elemental titanium and Ti-6Al-7Nb alloy. > Study of the interaction between titanium and processing tools. > Microstructural evolution of the materials with the processing temperature. increases. This is due to the interaction with the BN coated mould and leads to the formation of a reacted layer in the surface, composed by different titanium compounds, which greatly affect the mechanical properties. Nevertheless, the removal of this reacted layer leads to an important improvement of the ductility, especially for elemental titanium.

Quenching temperature influence on elastic and hardness behavior in a biocompatible Ti-based alloy

“…When quenching from the temperatures higher than T pt the alloy hardness somewhat decreases because the β-grain size was shown by microstructure to grow from 600 µm at T q = 1000°C to 900 µm at T q = 1050°C, and the forming α'-martensite needles coarsen correspondingly. The similar hardness dependence on quenching temperature along with the martensite formation was observed in the VT18U alloy [19] which contains about 6% of Al as well as the Ti6Al-7Nb alloy does but less amount of Nb (1.13%).…”

“…However, it should be noted that the alloy elasticity modulus value is less than that in the initial hot rolled alloy state because the elasticity modulus of the α-phase being the main part of the initial hot rolled alloy structure is higher than that of the α''-martensite forming under the quenching. After the quenching from the temperature of 950°C and higher the α'-martensite is observed in the alloy structure (Table 1), it exhibits higher elasticity modulus [19] compared to that of α-phase and, therefore, the alloy elasticity modulus values obtained are higher than those in the initial hot rolled alloy state and increase up to Tpt due to reducing primary α-phase volume fraction and growing α'-martensite volume fraction [14].…”

Behaviour of a biocompatible titanium alloy during orthogonal micro-cutting employing green machining techniques

“…However, the use of materials that remove vanadium (V-free) from titanium alloys for medical application has been debated since the mid-1980s in the USA [35]. It is because the potential toxicity of vanadium can cause cytotoxicity and adverse body tissue reactions [36].…”

“…Thus, new titanium alloys have been developed to replace the vanadium, such as the Ti-Mn [37], Ti-6Al-7Nb, Ti-5Al2.5Fe, Ti-13Nb-13Zr and Ti-35Nb-5Ta-7Zr titanium alloys [36].…”

Evaluation of the mechanical properties of powder metallurgy Ti-6Al-7Nb alloy

“…Because, as delivered, the master alloy was not suitable for its mixing with elemental titanium, the particle size was reduced by high energy ball milling and the ratio of the alloying elements adjusted to the desired composition by adding an elemental aluminium spherical powder bought from Sulzer Metco Ltd. The detailed route employed to obtain the Ti-6Al-7Nb powder is available in the literature (Bolzoni et al, 2012).…”