Armstrong process
The Armstrong process is used to refine titanium. Its output is particle-sized dust which can be sprayed into pattern-molds.[1][2][3] It was patented in 1999.[4] The output of this process has a "coral-like morphology", which differs from the traditional outputs like "spherical gas-atomized powder, mechanically crushed angular particles, or the titanium sponge morphology created during the Kroll process."[3]
History
The Armstrong process was patented in 1999.[4]
In 2016 a paper by MacDonald et al. told that the Armstrong powder was produced directly from the reduction of Titanium tetrachloride "in a continuous liquid loop", and cost only "11-24 USD/kg",[3] or roughly an order of magnitude higher than the price of steel.[5]
Description
The reducing agent for the Armstrong process is sodium, which is liquefied and introduced in a combined stream with titanium tetrachloride.[4]
![{\displaystyle {\ce {{TiCl4}+4{Na}->[98~^{\circ }\mathrm {C} ]{Ti}+4{NaCl}}}}](https://wikimedia.org/api/rest_v1/media/math/render/svg/88eeae85190869a42124cc5721bcda91f77387b9)
References
- ^ Araci, Kerem; Mangabhai, Damien; Akhtar, Kamal (2015). "Production of titanium by the Armstrong Process®". Titanium Powder Metallurgy. pp. 149–162. doi:10.1016/B978-0-12-800054-0.00009-5. ISBN 978-0-12-800054-0.
- ^ W.H.P. Bill, C.A. Blue, J.O. Kiggans, and J.D.K. Rivard, Powder Metallurgy and Solid State Processing of Armstrong Titanium and Titanium Alloy Powders, ITA Annual Conference 2007
- ^ a b c MacDonald, D.; Fernández, R.; Delloro, F.; Jodoin, B. (2017). "Cold Spraying of Armstrong Process Titanium Powder for Additive Manufacturing". Journal of Thermal Spray Technology. 26 (4): 598–609. Bibcode:2017JTST...26..598M. doi:10.1007/s11666-016-0489-2.
- ^ a b c U.S. patent 5,958,106
- ^ "Price History" (PDF). SteelBenchmarker. June 10, 2024. Retrieved 18 June 2024.