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

Autor: Liang Jiang, Linmao Qian, Changbang Deng
Rok vydání: 2021
Předmět:
Zdroj: ECS Journal of Solid State Science and Technology. 10:114003
ISSN: 2162-8777
2162-8769
Popis: 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.
Databáze: OpenAIRE