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]

${\displaystyle {\ce {{TiCl4}+4{Na}->[98~^{\circ }\mathrm {C} ]{Ti}+4{NaCl}}}}$