Formation and Evolution of Micro/Nano Periodic Ripples on 2205 Stainless Steel Machined by Femtosecond Laser

Abstract

The preparation of micro/nano periodic surface structures using femtosecond laser machining technology has been the academic frontier and hotspot in recent years. The formation and evolution of micro/nano periodic ripples were investigated on 2205 stainless steel machined by femtosecond laser. Using single spot irradiation with fixed laser fluences and various pulse numbers, typical ripples, including nano HSFLs (‖), nano LSFLs (⊥), nano HSFLs (⊥) and micro grooves (‖), were generated one after another in one test. The morphologies of the ripples were analyzed, and the underlying mechanisms were discussed. It was found that the nano holes/pits presented at all stages could have played a key role in the formation and evolution of micro/nano periodic ripples. A new kind of microstructure, named the pea pod-like structure here, was discovered, and it was suggested that the formation and evolution of the micro/nano periodic ripples could be well explained by the pea pod-like structure model.

Laser Writing of Multilayer Structural Colors for Full‐Color Marking on Steel

“…The formation of LSFL () is generally explained by the interference mechanism, [ 15 ] while the mechanism of the HSFL (‖) is still under debate. [ 16 ] Thereby, at a higher power of 110–120 mW, LIPSS forms clear and vivid colors on the stainless‐steel surface, as marked by the dotted box in Figure 3a. When the laser power continued to increase to 140 mW, as shown in Figure 3d, local excessive ablation or even melting occurs on the metal surface, forming irregular stripes on the metal surface, [ 17 ] and the color also becomes dim under such processing conditions.…”

Corrosion and Biofouling Behaviors of Self‐Organized Structures on Steel Surface Fabricated by Femtosecond Laser

“…[ 12 ] Xu et al obtained micro/nano periodic ripples on stainless steel 2205 using fs laser and investigated their evolution. [ 13 ] These ripples are classified as laser induced periodic surface structure (LIPSS). The formation of LIPSS has been extensively investigated, and the prevailing view believes that LIPSS is formed by self‐organization of surface material under the interference between the incident laser and the surface plasmons.…”