Phases of Titanium Combustion in Air

Formation of metal oxide nanoparticles in combustion of titanium and aluminum droplets

“…Using this value of δ and the pressure p in , we obtain the nitrogen concentration in the near-surface layer directly before the explosion C N ≈ 8%. This value of the concentration C N estimated as the lower bound agrees with the experimental data of [7], where C N = 10% for a titanium droplet of diameter 240 µm.…”

“…The nitrogen concentration in the droplet reaches 10%(at.) [7], which is not sufficient for the formation of solid-state TiN. In the first 150 msec of combustion, the droplet temperature reaches 2700 K and then declines to 2200 K, and the process is ended in an explosion [7] (see Fig.…”

“…By that time, the mean oxygen concentration in the particle is about 40%(at.) [7]. An increase in the dissolved-oxygen concentration leads to an increase in the phase-transition temperature.…”

“…The combustion of a single metal particle in air at atmospheric pressure is often treated as a simple physical model for the processes involved in particle combustion in energetic formulations or in technical devices. Therefore, the combustion of single particles under controlled conditions has been extensively studied theoretically and experimentally [1,[6][7][8]. A feature of the metal particle combustion mechanism is the formation of condensed oxide, originally in the form of nanosized particles.…”

Combustion of levitated titanium particles in air

“…Molodetsky et al [20] investigated combustion of titanium particles in the size range 240-280 µm in air. The falling particles were formed and ignited using a pulsed micro-arc that melted the edge of a consumable titanium wire electrode.…”