Molecular dynamics simulation of tin diffusion in float glass
Tin penetration occurring during the float glass forming process has great negative impact on the glass quality. And the tin diffusion coefficient is the key parameter for the tin diffusion simulation. Since detailed medium structure information of soda lime silica float glass over a wide composition range is still lacking, tin diffusion in glasses with composition of xNa2O-(1-x)SiO2 and xNa2O-(1-x)CaO-70SiO2 were simulated by molecular dynamics at temperature ranged from 873-1373K. Each simulation involved about 4000 atoms in a cell and Born-Mayer inter-atomic potentials were used. The Einstein equation is applied to compute the stannic ion ’s diffusion coefficient by mean square displacement. The result shows that diffusion coefficient of stannic tin is obviously higher at high temperature region and local diffusion coefficient hump appears at about 1100K. Moreover, the self-diffusion of stannic tin was larger in the sodium silicate glass with less sodium content. As for the sodium calcium silicate glass, it was found that the diffusion coefficient is smaller with less calcium at the same mole ratio of SiO2 in sodium calcium silicate glass. Diffusion coefficient calculated by molecular dynamics is in the same order of the experimental result. Reduced glass near the entrance of tin bath should be controlled strictly in order to avoid the oxidation of tin and the residual time in the high temperature region should be shortened since the temperature has a more obvious influence on the diffusion coefficient.
ZHANG Qin CHEN Ze-Jing LI Zhi-Xin
Key Laboratory for Thermal Science and Power Engineering of Ministry of Education School of Aerospace,Tsinghua University Beijing, China,100084
国际会议
The Ninth Asian Thermophysical Properties Conference(第九届亚洲热物理性能会议 ATPC 2010)
北京
英文
397-401
2010-10-19（万方平台首次上网日期，不代表论文的发表时间）