Generation of structural colors on pure magnesium surface using the vibration-assisted diamond cutting

The light metal magnesium has wide applications in automotive, electronics, and biomedical industries attributing to its superior properties. However, the fabrication of the micro/nanostructures on its surface, especially in the generation of structural colors, remains a challenge. Here we report the generation of structural colors on pure magnesium surface using the vibration-assisted diamond cutting (VADC) process in which the diamond cutting tool regularly vibrates on the pure magnesium surface to fabricate the microstructures using the controllable vibration frequency. The periodic saw-tooth-like microstructures with the spacing of 1.65 μm and 1.45 μm are successfully fabricated by the VADC process. The fabricated microstructures act as the diffraction grating that induces the generation of structural colors. Two groups of structural colors (coral color and green color; blue color and magenta color) are clearly observed at the viewing angle of 50° and 65°, respectively. Moreover, a detailed analysis is conducted to demonstrate the relationship between the spacing of grating and the cutting force.