Influence of β-Stabilizers on the α-Ti→ω-Ti Transformation in Ti-Based Alloys

Processes

Askar Kilmametov¹  Brigitte Baretzky¹  Boris Straumal¹  Pawel Zięba²  Anna Korneva²  Mikhail Karpov³  Natalia Afonikova³  Alena Gornakova³ 

[1] Institute for Nanotechnology, Karlsruhe Institute of Technology (KIT), Hermann-von-Helmholtz-Platz 1, 76344 Eggenstein-Leopoldshafen, Germany;Institute of Metallurgy and Materials Science, Polish Academy of Sciences, Reymonta St. 25, 30-059 Cracow, Poland;Institute of Solid State Physics, Russian Academy of Sciences, Ac. Ossipyan str. 2, 142432 Chernogolovka, Russia;

关键词: Ti-alloys;    α-Ti→ω-Ti transformation;    β-stabilizers;    high-pressure torsion;    mass transfer;   

DOI  :  10.3390/pr8091135

来源: DOAJ

【 摘 要 】

The development of next generation Ti-based alloys demand completely new processes and approaches. In particular, the Ti-alloys of next generation will contain not only α-Ti and β-Ti phases, but also small amounts of ω-phase and intermetallic compounds. The β→ω phase transformation induced by high-pressure torsion (HPT) has been studied in detail recently. In this work, we investigated the HPT-induced α→ω phase transformation. For this purpose, we added various β-stabilizers into α-Ti matrix of studied Ti-alloys. Ti-alloys with 4% Fe, 2% Cr, 3% Ni, and 4% Co (wt. %) have been annealed at the temperatures below their point of eutectoid decomposition, from β-Ti to α-Ti, and respective intermetallics (TiFe, Ti₂Co, Ti₂Ni, TiCr₂). Volume fraction of HPT-driven ω-phase (from ≤5 up to ~80%) depended on the amount of alloying element dissolved in the α-matrix. Evaluation of lattice parameters revealed accelerated mass transfer during HPT at room temperature corresponding to bulk diffusion in α-Ti at ~600 °С.

【 授权许可】

Unknown