Low-cost Titanium: 'Affordable Ti': Session I
Sponsored by: TMS Structural Materials Division, TMS: Titanium Committee, TMS: Powder Materials Committee
Program Organizers: Ramana Reddy, University of Alabama; M. Ashraf Imam, George Washington University
Monday 8:00 AM
February 24, 2020
Room: Theater A-8
Location: San Diego Convention Ctr
Session Chair: Ashraf Imam, George Washington University; Ramana Reddy, The University of Alabama
8:00 AM Invited
Electrodeposition of Titanium Aluminide (TiAl) Alloy from AlCl3-BMIC Ionic Liquid at Low Temperature: Pravin Shinde1; Yuxiang Peng1; Ramana Reddy1; 1The University of Alabama
Titanium and its intermetallic titanium aluminide (TiAl) alloys are technologically exciting materials due to their unique thermomechanical properties such as low density, excellent strength, and exceptional corrosion resistance. Herein, we demonstrated a low-cost route to electrodeposit TiAl alloy from liquid (IL) using a 2:1 molar ratio of aluminum chloride (AlCl3) and 1-butyl-3-methylimidazolium chloride (BMIC). The cyclic voltammetry (CV) and chronoamperometry (CA) techniques were used to investigate the electrosynthesis parameters. The electrodeposition of phase-pure TiAl was accomplished on a copper cathode at a constant potential at 100°C in a three-electrode configuration that involved Ti slab counter electrode (anode) as a sacrificial donor source of Ti ions in the IL and titanium wire as a reference electrode. The electrodeposited TiAl alloy electrodes were characterized using scanning electron microscopy, energy dispersive X-ray spectroscopy, and X-ray diffraction methods. The electrodeposited TiAl alloy exhibited uniform, smooth, and compact morphology.
8:40 AM
Calciothermic Synthesis of Fine, Hydrogenated Ti- and Ti-Nb-powder: Inge Lindemann1; Patrick Langhelm1; Margitta Uhlemann1; Annett Gebert1; 1Leibniz Institute for Solid State and Materials Research Dresden
Titanium and its alloys show extraordinary properties but usage is still limited owing to the high cost of the material and demanding processing. Near-net shape processes have promising potential for substantial savings but powder is additionally expensive due to titanium’s high oxygen affinity. Therefore we elucidate an alternative pathway to synthesize hydrogenated Ti- and Ti-Nb-powder by calciothermic low temperature reduction. Especially synthesis of fine powder with particle sizes < 45 µm is interesting because it is only a small fraction after conventional gas atomisation. HDH Ti powder can be produced easily in small size but morphology is angular. Hydrogenated Ti and Ti-Nb powder is made reducing their oxides TiO2 and Nb2O5 with CaH2 in H2 atmosphere. Particle size and morphology can be tailored by size and morphology of the starting materials as well as the activation procedure. The project was funded by the DFG (LI 2536/1-1).
9:00 AM
Production of Fine Titanium and Titanium Alloy Powders by the Shuttle of Disproportion Reaction in Molten Salt: Xin Lu1; Takuya Ono1; Haochen Jiang1; Osamu Takeda1; Hongmin Zhu1; 1Tohoku University
Low cost and high-quality titanium powder is crucial for powder metallurgy (PM) and additive manufacturing (AM) of titanium to significantly decrease the manufacturing cost. In this study, the production of titanium and titanium alloy powders from titanium sponge was studied through the shuttle of disproportionation reaction (Ti(II)→Ti(III)+Ti(powder)) and its backward reaction (Ti(III)+Ti(bulk)→Ti(II)) of Ti ions in molten salt. With the addition of a very small amount of TiCl2, over 7~70 times of titanium powder in mass comparing to the added titanium ion was obtained. Further, by introducing aluminium metal into the salt, fine Ti-Al powder with homogeneous composition and particle size distribution was obtained. The primary particle size of the powder formed was found approximately 1 μm, while the secondary agglomerated particle size was in the range of 25 ~ 50 μm. The proposed method is expected to significantly decrease the production cost of titanium and titanium alloy powders.
9:20 AM
Cost-effective PM Ti Compositions and Processing: Leandro Bolzoni1; 1The University of Waikato
Titanium is the materials of choice for critical and advanced applications (e.g. biomedicine and aerospace) due to both its excellent properties and high cost. Creative fabrication techniques and synthesis of alternative compositions are both aspects that could be considered to achieve more cost-affordable Ti products for its wider adoption in cost-driven industries. The aim of this work is to analyse the potential of manufacturing of newly designed Ti alloys via combining near net shape powder metallurgy processing and low-cost alloying elements. Demonstration of the feasibility and validity of the different methods proposed is addressed using diverse classes of Ti-based materials including alpha, alpha+beta and high strength metastable beta Ti alloys. The characteristics of the microstructural features (residual porosity and phases) can be changed to adjust the mechanical response depending on the requirements. Evidences are provided that through appropriate processing these newly-design cost-effective compositions could be used for structural engineering applications.
9:40 AM Break
9:55 AM Invited
Fast Step 3- Titanium Swarf to Engine Parts in 3 Steps: Martin Jackson1; Ben Thomas1; Nick Weston1; 1The University of Sheffield
This project utilises high value alloyed titanium alloy swarf/turnings as a feedstock to sinter-forge via the new, novel technology FAST-forge process into near net shapes for use in high strength and good fatigue life applications typically required within an automotive engine. The aim is to produce engine components of increasing complexity from both a manufacturing and performance perspective and to undertake functional bench testing.To achieve this a new UK supply chain is being developed, with diversification for companies within traditional metal manufacturing and ‘know-how’ transfer from the University of Sheffield, combined with multiple areas for IP generation. The FAST process has existed for many years but when combined with forging it can release its untapped potential. The process aims to produce titanium at 20% of the cost of current titanium billet and with minimal waste compared to the 70% waste typically generated from current processes.
10:35 AM
Aeration Leaching Process for Producing Synthetic Rutile in a Novel Gas-liquid-solid Reactor: Qiuyue Zhao1; Maoyuan Li1; Zimu Zhang1; Ting-an Zhang1; 1Northeastern University
The Synthetic rutile was prepared by aeration leaching process in a novel gas-liquid-solid reactor and compared with traditional reactor. The effects of aeration leaching on the phase transformation of reduced ilmenite were studied at a liquid-to-solid ratio of 4:1 by XRD, while the microstructure and composition of the reduced ilmenite were characterized by SEM and chemical analysis. The vigorous stirring helped break bubbles and was favorable to the reaction. There exists an optimum value of gas flow rate. Using this process, synthetic rutile containing 0.6% metallic iron and 82.11% titanium dioxide were obtained at 2% ammonium chloride with 1.5% hydrochloric acid and reaction time 1 hour.