No abstract

Diffusivities of nitrogen and argon in a borosilicate glass were determined with two different methods: (1) from gas exchange experiments between molten glass and bubbles containing nitrogen and argon, and (2) from solution rates of nitrogen and argon in glass during saturation experiments. Between 1200°C and 1580°C the diffusion coefficients of nitrogen and argon yielded the following equations:      − = − RT s m DN 134900 exp 10 22 . 1 ] / [ 6 . 2 2 and      − = − RT s m DAr 125300 exp 10 08 . 1 ] / [ 6 . 2 , with R=8.314 J/(mol.K). The solubilities and residual gas concentration in the glass which are necessary for the calculation of the diffusivities were determined with the high temperature vacuum extraction method.