Theoretical and experimental investigation on the radial-fly-cutting process for micro-structured surface fabrication

Radial-fly-cutting (RFC) is a promising technique for the fabrication of micro-structured surfaces. In this paper, the generation of both micro-structured surfaces and hierarchical-structured surfaces under four modes of RFC were theoretically investigated and experimentally validated for the first time. A novel mode of RFC, named servo-assisted helix-feeding radial-fly-cutting (SA-HFRFC) was proposed for fabricating intricate hierarchical -structured surfaces with high efficiency. Considering system configuration and the material removal process during RFC, a novel surface generation algorithm catering for all processing modes was proposed to calculate and predict the intricate micro-structured surfaces. Numerical simulations were conducted to predict the micro -structured surfaces and demonstrate the good effectiveness of the algorithm in the surface calculation. Machining experiments of micro-structured surfaces and hierarchical structured surfaces under four modes of RFC were conducted, which validated the good agreements between the simulations and experiments. Under SA-HFRFC, an intricate primary surface, which is modulated with a 12-cycle sine curve governed by the polar angle, was designed and fabricated, and the secondary microgrooves regularly superimposed on the PS were deter-ministically fabricated. It was demonstrated that RFC features a strong capacity for the fabrication of both micro -structured surfaces and intricate hierarchical-structured surfaces. This work will contribute to studies on the ultra-precision machining process and deterministic fabrication of both micro-structured surfaces and hierarchical-structured surfaces.