(The) diffusion of hydrogen in pure liquid copper and copper-silicon alloys

Abstract

The diffusivity of hydrogen in pure liquid copper was determined by an unsteady-state gas liquid metal diffusion cell technique. The diffusion cell was formed by immersing an alumina tube containing hydrogen gas at 1 atm. in a bath of stagnant liquid copper. Diffusivities were calculated from the appropriate solution of Fick``s 2nd law. The effect of silicon, an alloying element, on the diffusion of hydrogen was also investigated. The result showed that silicon decreased the hydrogen diffusion coefficient up to 2 wt. pct concentration but more silicon content increased the diffusion coefficient of hydrogen. The absorption of hydrogen in stagnant pure liquid copper has been found to be diffusion controlled. The calculated diffusivities, $D_H$, for hydrogen in pure liquid copper can be discribed by the equation; $$D_H = 5.028 \times 10^{-2}\exp(-2,628\pm 1,290/RT) cm^2/\sec$$ in the temperature range of $1,090\,^\circ\!C - 1,205\,^\circ\!C$.