Titanium-hydrogen interaction at megabar pressure

TL;DR

This study investigates how titanium particles dissolve in warm dense hydrogen at megabar pressures, revealing rapid dissolution times and a diffusion-driven mixing process, with implications for nuclear energetics.

Contribution

It provides the first detailed thermodynamic and kinetic analysis of titanium ejecta dissolution in high-pressure hydrogen using molecular dynamics methods.

Findings

Titanium particles of 1 μm dissolve in hydrogen within 0.015 μs.

Dissolution follows a diffusion law, leading to homogenized titanium-hydrogen fluid.

The process is applicable under various conditions where titanium and hydrogen are atomic fluids.

Abstract

The process of transport of metal particles ($\mathit{ejecta}$) in gases is the subject of recent works in the field of nuclear energetics. We studied the process of dissolution of titanium ejecta in warm dense hydrogen at megabar pressure. Thermodynamic and kinetic properties of the process were investigated using classical and quantum molecular dynamics methods. We estimated the dissolution time of ejecta, the saturation limit of titanium atoms with hydrogen and the heat of dissolution. It was found that particles with a radius of 1 $\mu m$ dissolve in hydrogen in time of $1.5 \cdot 10^{-2} \ \mu s$, while the process of mixing can be described by diffusion law. The presented approach demonstrates the final state of the titanium-hydrogen system as a homogenized fluid with completely dissolved titanium particles. This result can be generalized to all external conditions under which titanium and hydrogen are atomic fluids.