Soft abrasive flow polishing based on the cavitation effect

The fluid medium used for soft abrasive flow (SAF) is of low viscosity and high flow velocity. The conventional SAF processing method is widely used due its ability to avoid damage and its adaptability of the workpiece surface. However, the current SAF method also suffers from limitations such as long polishing times and low processing efficiency. To address these issues, this paper proposes a method based on the cavitation effect to assist the soft abrasive flow polishing, termed CSAF. First, the working mechanism of CSAF is introduced through a schematic diagram. In addition, a CSAF fluid mechanic model is configured on the basis of the mixture multiphase model and cavitation model. Then, the distribution of key flow parameters, such as the velocity, dynamic pressure, and turbulent kinetic energy, is obtained and compared through computational fluid dynamic software. Numerical analysis results show that the flow field assisted by the cavitation effects shows better processing performance than SAF. Finally, particle imaging velocity (PIV) observation and experimental processing platforms are established, and extensive experiments are conducted. The processing comparison experiments showed that the abrasive flow assisted by the cavitation effect can lower the workpiece surface roughness to 3.46 nm with a satisfactory surface quality over a shorter time than the SAF method. The numerical analysis results are aligned with the PIV observation and the polishing experiment results. The SAF polishing method based on the cavitation effect significantly increases the polishing efficiency.