Temperature Effect on Capillary Flow Dynamics in 1D Array of Open Nanotextured Microchannels Produced by Femtosecond Laser on Silicon

Capillary flow of water in an array of open nanotextured microgrooves fabricated by femtosecond laser processing of silicon is studied as a function of temperature using high-speed video recording. In a temperature range of 23–80 °C, the produced wicking material provides extremely fast liquid flow with a maximum velocity of 37 cm/s in the initial spreading stage prior to visco-inertial regime. The capillary performance of the material enhances with increasing temperature in the inertial, visco-inertial, and partially in Washburn flow regimes. The classic universal Washburn’s regime is observed at all studied temperatures, giving the evidence of its universality at high temperatures as well. The obtained results are of great significance for creating capillary materials for applications in cooling of electronics, energy harvesting, enhancing the critical heat flux of industrial boilers, and Maisotsenko cycle technologies.

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Holographic femtosecond laser manipulation for advanced material processing

Advanced Optical Technologies ◽

10.1515/aot-2015-0062 ◽

2016 ◽

Vol 5 (1) ◽

Author(s):

Satoshi Hasegawa ◽

Yoshio Hayasaki

Keyword(s):

Material Processing ◽

Femtosecond Laser ◽

Laser Processing ◽

High Speed ◽

Large Scale ◽

High Energy ◽

Material Surface ◽

Two Photon ◽

Computer Generated Hologram ◽

Femtosecond Laser Processing

AbstractParallel femtosecond laser processing using a computer-generated hologram displayed on a spatial light modulator, known as holographic femtosecond laser processing, provides the advantages of high throughput and high-energy use efficiency. Therefore, it has been widely used in many applications, including laser material processing, two-photon polymerization, two-photon microscopy, and optical manipulation of biological cells. In this paper, we review the development of holographic femtosecond laser processing over the past few years from the perspective of wavefront and polarization modulation. In particular, line-shaped and vector-wave femtosecond laser processing are addressed. These beam-shaping techniques are useful for performing large-area machining in laser cutting, peeling, and grooving of materials and for high-speed fabrication of the complex nanostructures that are applied to material-surface texturing to control tribological properties, wettability, reflectance, and retardance. Furthermore, issues related to the nonuniformity of diffraction light intensity in optical reconstruction and wavelength dispersion from a computer-generated hologram are addressed. As a result, large-scale holographic femtosecond laser processing over 1000 diffraction spots was successfully demonstrated on a glass sample.

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High speed and low roughness micromachining of silicon carbide by plasma etching aided femtosecond laser processing

Ceramics International ◽

10.1016/j.ceramint.2020.04.097 ◽

2020 ◽

Vol 46 (11) ◽

pp. 17896-17902 ◽

Cited By ~ 1

Author(s):

Chen Wu ◽

Xudong Fang ◽

Feng Liu ◽

Xin Guo ◽

Ryutaro Maeda ◽

...

Keyword(s):

Silicon Carbide ◽

Femtosecond Laser ◽

Plasma Etching ◽

Laser Processing ◽

High Speed ◽

Femtosecond Laser Processing

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Superwicking Functionality of Femtosecond Laser Textured Aluminum at High Temperatures

Nanomaterials ◽

10.3390/nano11112964 ◽

2021 ◽

Vol 11 (11) ◽

pp. 2964

Author(s):

Ranran Fang ◽

Xianhang Zhang ◽

Jiangen Zheng ◽

Zhonglin Pan ◽

Chen Yang ◽

...

Keyword(s):

Femtosecond Laser ◽

Capillary Flow ◽

Global Climate ◽

Generation Efficiency ◽

Periodic Surface ◽

Temperature Heat ◽

Inertial Flow ◽

Inertial Regime ◽

Water Spreading ◽

Aluminum Material

An advanced superwicking aluminum material based on a microgroove surface structure textured with both laser-induced periodic surface structures and fine microholes was produced by direct femtosecond laser nano/microstructuring technology. The created material demonstrates excellent wicking performance in a temperature range of 23 to 120 °C. The experiments on wicking dynamics show a record-high velocity of water spreading that achieves about 450 mm/s at 23 °C and 320 mm/s at 120 °C when the spreading water undergoes intensive boiling. The lifetime of classic Washburn capillary flow dynamics shortens as the temperature increases up to 80 °C. The effects of evaporation and boiling on water spreading become significant above 80 °C, resulting in vanishing of Washburn’s dynamics. Both the inertial and visco-inertial flow regimes are insignificantly affected by evaporation at temperatures below the boiling point of water. The boiling effect on the inertial regime is small at 120 °C; however, its effect on the visco-inertial regime is essential. The created material with effective wicking performance under water boiling conditions can find applications in Maisotsenko cycle (M-cycle) high-temperature heat/mass exchangers for enhancing power generation efficiency that is an important factor in reducing CO2 emissions and mitigation of the global climate change.

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