The Armstrong process is used to refine titanium. Its output is particle-sized dust which can be sprayed into pattern-molds. It was patented in 1999. 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."
History The Armstrong process was patented in 1999. 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", or roughly an order of magnitude higher than the price of steel.
Description The reducing agent for the Armstrong process is sodium, which is liquefied and introduced in a combined stream with titanium tetrachloride.
TiCl 4 + 4 Na → 98 ∘ C Ti + 4 NaCl {\displaystyle {\ce {{TiCl4}+4{Na}->[98~^{\circ }\mathrm {C} ]{Ti}+4{NaCl}}}}
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