Synthesis of Ternary Ti-25Nb-11Sn Alloy by Powder Metallurgy Route Using Titanium Hydride Powder

Abstract

In the present work, Ti-25Nb-11Sn (mass%) alloys were successfully prepared by an advanced powder metallurgy method. The alloys were synthesized by mechanical milling of powder mixture, consisting of titanium hydride (TiH 2 ), elemental niobium (Nb) and elemental tin (Sn) powders, followed by their consolidation via Spark Plasma Sintering (SPS) method. The use of brittle TiH 2 powder, instead of ductile elemental Ti powder, resulted in ~100% powder yield of mechanically milled (MMed) powder even after long time mechanical milling. The resulting MMed powders consisted of homogeneously distributed nano-sized titanium/niobium hydride powder particles together with a few micron-sized pure Nb particles. The mechanical milling also led to the lowering of dehydrogenation temperature of the hydride particles. Sintering of short time mechanically milled powder (72 ks) resulted in the ne-grained heterogeneous microstructure consisting of β phase and orthorhombic martensitic α phase. On the other hand, sintering of long time mechanically milled powder (180 ks) resulted in the evolution of β-phase and α-phase. The specimen containing α+β phase exhibited higher average hardness as compared to the average hardness of specimen containing α +β phase.

Mechanical, Corrosion, and Ion Release Studies of Ti-34Nb-6Sn Alloy with Comparable to the Bone Elastic Modulus by Powder Metallurgy Method

“…In the literature, the feasibility of the mechanical properties for orthopedic implants of porous Ti-Nb-Sn alloys has been demonstrated [29][30][31][32][33][34][35]. The Ti-Nb-Sn system is a nontoxic alternative with low-elastic moduli for medical implants.…”

“…The high strength and low elastic modulus achieved in Ti-Nb-Sn alloys is related to the occurrence of stress-induced martensitic transformation and its reverse transformation [33]. The addition of Nb and Sn decreases the maximum martensitic transformation strain [32]. For the present study, 34 and 6 wt.% of Nb and Sn were chosen to promote the stabilization of β phase, respectively [36].…”

Influence of processing parameters on dehydrogenation of TiH2 in the preparation of Ti–Nb: A review

“…Similarly, Sharma et al. [ 92 ] reported that TiH 2 with a small particle size and a larger surface area could achieve a higher hydrogen decomposition percentage. Mechanical milling was used to create Ti-25-Nb-11Sn alloy from TiH 2 , Nb, and Sn, which was then consolidated using Spark Plasma Sintering (SPS) at two different milling times (72 ks and 180 ks).…”

An Efficient Powder Metallurgy Processing Route to Prepare High-Performance β-Ti–Nb Alloys Using Pure Titanium and Titanium Hydride Powders

“…Moreover, the use of extremely brittle TiH 2 powder, instead of highly ductile pure titanium powder, can overcome the sticking/agglomeration issues as well as contamination-related issues by avoiding process control agents (PCAs) in the mechanical milling process. As a result, a uniform distribution of elemental powders with an almost complete powder yield can be ensured even a long time after mechanical alloying [21][22][23]. It has also been reported that various properties, such as grain refinement, improvement in superplastic forming and reduction in the flow stress, can be improved through temporary hydrogen alloying [24][25][26][27][28][29][30].…”