Functional films with multi-directional wavy microgrooves can be applied to reduce fluid drag in turbulent flow applications. For high-efficiency mass production of functional films through polymer imprinting, it is necessary to machine wavy microgrooves on the surfaces of metal roll molds. When wavy grooves are cut, to reduce the follow-up errors of machine tools, a very low cutting speed is normally used, but the mechanism of this cutting is still unclear. In this study, microgrooving experiments were conducted on three different workpiece materials: brass, oxygen free copper, and aluminum alloy, and their cutting mechanisms were investigated. Distinct differences in chip formation behavior and machined surface integrity were identified among these materials. Aluminum alloy was chosen as the most suitable material for roll mold fabrication. Two-directional wavy microgrooves with form accuracy on 1 μm level and surface roughness of less than 10 nm Ra were obtained.

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