Engineering:Armstrong process

From HandWiki

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]

TiCl4+4Na98ACTi+4NaCl

References

  1. 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. 
  2. 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
  3. 3.0 3.1 3.2 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. doi:10.1007/s11666-016-0489-2. Bibcode2017JTST...26..598M. 
  4. 4.0 4.1 4.2 U.S. Patent 5,958,106
  5. "Price History". June 10, 2024. http://steelbenchmarker.com/history.pdf.