Synergistic Effect of F⁻and Persulfate in Efficient Titanium Alloy Chemical Mechanical Polishing

Abstract

Titanium alloys require excellent surface quality to achieve superior performance in biomedicine. In this paper, chemical mechanical polishing (CMP) was employed to prepare a satisfactory TC4 alloy surface. F− and persulfate were used as critical additives to improve the CMP efficiency. In comparison with the basic slurry without F− and persulfate, the slurry containing only F−, and the slurry containing only persulfate, the slurries containing both F− and persulfate lead to a noticeable increase in the material removal rate (MRR), which is attributed to the synergistic effect of F− and persulfate. After adding 80 mM NaF and 100 mM (NH4)2S2O8 to the basic slurry, the MRR increases significantly from 11 nm min−1 to 203 nm min−1, and the surface roughness R a reaches 3.4 nm. Moreover, there is no processing damage in the substrate. For the synergistic effect, Ti in TC4 alloy is first oxidized to Ti3+ and Ti4+ oxides by persulfate, and then HF, F− and HF2 − attack the oxides to produce soluble complex compounds, promoting the corrosion and the resultant MRR. This study provides a feasible way to achieve the high-efficiency CMP of titanium alloys via the synergistic effect of complexing agent and oxidizer to enhance the corrosive wear.

Parameters Optimization of Active Flexible Tool‐Assisted Shear Thickening Polishing Method for Concave Surface

“…The number of abrasive particles involved in polishing is increased correspondingly with the decrease of abrasive size under the same mass fraction. However, the research [27][28][29] shows that the peak viscosity of the STP slurry decreases with the decrease of abrasive size, and the removal efficiency of polishing slurry decreases accordingly. It explains why S/N ratio of surface roughness (S a ) exhibits an initial increase followed by a decrease with the increase in abrasive particle size, while S/N ratio of MRR shows an increase with the increase in abrasive particle size.…”

Preparation of the Nanodiamond@SiO2 Abrasive and its Effect on the Polishing Performance of Zirconia Ceramics

“…8 Chemical mechanical polishing (CMP) is an ultra-precision machining technology that combines mechanical grinding and chemical corrosion. [9][10][11] The polishing slurry is a crucial part of CMP, containing abrasives, chemicals, and so on. 12,13 Among them, nanodiamond (ND) abrasives are characterized by ultra-hardness and large specific surface area, which brings to outstanding mechanical polishing effect and high material removal rate.…”