2023 年 68 巻 1 号 p. 15-20
Multi-scale texturing and surface modification have the potential to develop higher functions and new functions. As a method for efficiently creating a fine structure, laser-induced periodic surface structure (LIPSS) is attracting attention which is a periodic nanostructure with the periodicity depending on the laser wavelength fabricated in a self-organized manner by ultrashort-pulsed laser ablation on a material surface. It has been reported that LIPSS can control the tribology, wettability and optical properties. However, the functions of LIPSS are limited since the geometry of LIPSS depends on the pulse duration, wavelength and material. Therefore, we developed methods to utilize other processing processes for ultrashort-pulsed laser processing to control nanostructures, fabricate hybrid structures and modify the material surface. The ultra-precision cutting assisted ultrashort-pulsed laser was able to improve the straightness, uniformity, and aspect ratio of LIPSS by promotion of surface plasmons, and to create multiscale structures. Moreover, by compositing electrochemical machining, multi-scale structures can be created with improving the machining efficiency due to the increase of the electric field intensity, and the microstructure can be created while controlling the surface composition.
