Currently, laser surface treatment (LST) is considered the most promising method available within the industry. It delivers precise control over surface topography, morphology, wettability, and chemistry, making the technique suitable for regulating the corrosion behavior of alloys. In this paper, femtosecond laser texturing with different parameters and atmosphere environments was adopted to clarify the effect of surface treatment on the corrosion resistance of selective laser melted (SLM-ed) 17-4PH stainless steel (SS) in a NaCl solution. The experimental results show that, after the heat treatment, the corrosion resistance of the laser-treated samples was enhanced. With the further laser treatment in an argon atmosphere, the oxidation of nanostructural surfaces was avoided. The Cr, Cu, and other alloying elements precipitated on the laser-ablated surface were beneficial to the formation of a passivation film, leading to an improved corrosion resistance performance.
Many biological surfaces with hierarchical structures exhibit super wetting properties, but a multiscale hierarchical metal surface with superhydrophilic performance is difficult to be fabricated using a simple method. In this work, we report a large area micro/nanotextured superhydrophilic silicon surface fabricated by a laser direct writing technique. The combination of a microscale column structure and randomization-distributed nano-bumps decorated on the column enhances the superhydrophilic properties, with the contact angle reduced substantially from about 46°to 0°, where the droplets are able to spread rapidly within 591 ms. The water wetting orientation can be regulated by controlling the shape of microcolumns on the surface. Moreover, our results show that the fabricated surface with the hierarchical structure has better droplet shape control performance and higher fog collection efficiency compared to a smooth surface. These surfaces have potential applications in heat exchangers, biosensors, cell adhesives, and self-cleaning solar cells.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.