Isotropic etching polishing (IEP), which is based on the merging of hemispherical holes that are formed by isotropic etching, is proposed in this study as a universal metal finishing approach. Modeling of the surface evolution during IEP is also carried out, and the formation of a metal surface is predicted. The etching anisotropy of titanium is experimentally studied, and the results show that isotropic etching can be realized under optimized conditions. Isotropic etching sites originate from a breakdown of the passivation layer. Both the density and growth rate of the holes are affected by the current, and a large etching current is preferred for the realization of highly efficient polishing. IEP has been shown to be effective and efficient for surface finishing of TA2. The surface Sa roughness is drastically reduced from 64.1 nm to 1.2 nm, and a maximum polishing rate of 15 μm/min is achieved under an etching current of 3 A. IEP has also been successfully applied for surface finishing of other metals, including TC4, stainless steel 304, aluminum alloy 6063 and pure nickel, demonstrating that IEP can be considered a universal approach for finishing metals.

在这项研究中，作为一种通用的金属精加工方法，提出了基于各向同性蚀刻形成的半球形孔合并而成的各向同性蚀刻抛光（IEP）。还对IEP期间的表面演变进行了建模，并预测了金属表面的形成。实验研究了钛的刻蚀各向异性，结果表明在最佳条件下可以实现各向同性刻蚀。各向同性的蚀刻部位源自钝化层的击穿。孔的密度和生长速率都受到电流的影响，并且为了实现高效抛光，优选大的蚀刻电流。已经证明，IEP对于TA2的表面处理是有效的。表面Sa 粗糙度从64.1 nm大幅降低至1.2 nm，在3 A蚀刻电流下最大抛光速率为15μm/min。IEP还已成功应用于其他金属的表面精加工，包括TC4，不锈钢304 ，铝合金6063和纯镍，证明了IEP可被视为一种用于金属精加工的通用方法。