ABSTRACT

To contribute to quantifying the process of electropolishing, the rates of electropolishing of a horizontal cylinder with active ends were studied under natural convection by measuring the limiting current of the anodic dissolution of copper cylinders in H₃PO₄. Cylinder diameters and H₃PO₄ concentrations were changed to provide a wide range of Sc⋅Gr (Schmidt and Grashof numbers). The data for a horizontal cylinder with active ends for the conditions $8.3\times {10}^4$ < Sc < $3.6\times {10}^5$, 6.5 × 10⁸ < Sc⋅Gr > $1.6\times {10}^{11}$ were correlated by the equation $\mathrm{S}\mathrm{h}=0.049(\mathrm{S}\mathrm{c}.\mathrm{G}\mathrm{r}{)}^{0.3}$. For hollow horizontal cylinders (pipes) the outer surface data fit the equation $\mathrm{S}\mathrm{h}=0.8(\mathrm{S}\mathrm{c}.\mathrm{G}\mathrm{r}{)}^{0.28}$. Comparison of the equations obtained for a horizontal cylinder with the equations obtained by previous studies on vertical cylinders with active ends revealed that the orientation of the workpiece plays an important role in determining the rate of electropolishing.

摘要

为了有助于量化电解抛光过程，通过测量铜圆柱在 H ₃ PO _{4 中}阳极溶解的极限电流，研究了在自然对流下具有活动端的水平圆柱的电解抛光速率。气缸直径和 H ₃ PO ₄浓度已更改，以提供范围广泛的 Sc⋅Gr（施密特数和格拉肖夫数）。条件下具有活动端的水平圆柱体的数据$8.3\times {10}^4$ < Sc < $3.6\times {10}^5$, 6.5 × 10 ⁸ < Sc⋅Gr >$1.6\times {10}^{11}$ 由等式相关 $\mathrm{秒}\mathrm{H}=0.049(\mathrm{秒}\mathrm{C}.\mathrm{G}\mathrm{r}{)}^{0.3}$. 对于中空的水平圆柱（管），外表面数据符合方程$\mathrm{秒}\mathrm{H}=0.8(\mathrm{秒}\mathrm{C}.\mathrm{G}\mathrm{r}{)}^{0.28}$. 将水平圆柱体获得的方程与先前对具有活动端的垂直圆柱体研究获得的方程进行比较，表明工件的方向在确定电解抛光速率方面起着重要作用。