Advances in Laser Drilling of Structural Ceramics

The high-quality, high-efficiency micro-hole drilling of structural ceramics to improve the thermal conductivity of hot-end parts or achieve high-density electronic packaging is still a technical challenge for conventional processing techniques. Recently, the laser drilling method (LDM) has become the preferred processing tool for structural ceramics, and it plays an irreplaceable role in the industrialized processing of group holes on structural ceramic surfaces. A variety of LDMs such as long pulsed laser drilling, short pulsed laser drilling, ultrafast pulsed laser drilling, liquid-assisted laser drilling, combined pulse laser drilling have been developed to achieved high-quality and high-efficiency micro-hole drilling through controlling the laser–matter interaction. This article reviews the characteristics of different LDMs and systematically compares the morphology, diameter, circularity, taper angle, cross-section, heat affect zone, recast layer, cracks, roughness, micro–nano structure, photothermal effect and photochemical reaction of the drilling. Additionally, exactly what processing parameters and ambient environments are optimal for precise and efficient laser drilling and their recent advancements were analyzed. Finally, a summary and outlook of the LDM technology are also highlighted.

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Fabrication of Fine Mesh Filter Screen with Pulsed Laser

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.516.54 ◽

2012 ◽

Vol 516 ◽

pp. 54-59

Author(s):

Keiji Ogawa ◽

Heisaburo Nakagawa ◽

Fumiya Murase ◽

Susumu Nishida

Keyword(s):

Small Diameter ◽

Pulsed Laser ◽

Batch Process ◽

Laser Drilling ◽

Hole Drilling ◽

Drilling Process ◽

Diameter Hole ◽

Fine Mesh ◽

Fine Pitch ◽

Filter Screen

This paper proposes a novel manufacturing process of a fine mesh filter screen with a pulsed laser. The fine mesh filter screen, made of stainless steel, has many small diameter holes with high aspect ratio and fine pitch. In the conventional process, an electron beam drills in a vacuum. However, this is very costly because of the expensive equipment required and batch process. Therefore, a laser drilling process for small diameter hole drilling in air with higher flexibility was proposed. The post-processes after the laser drilling completed the fine mesh filter screen.

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Ultrasound-assisted pulsed laser drilling for fabricating high quality microholes

2017 Conference on Lasers and Electro-Optics Pacific Rim (CLEO-PR) ◽

10.1109/cleopr.2017.8119095 ◽

2017 ◽

Author(s):

Houxiao Wang ◽

Naifei Ren ◽

Lin Li ◽

Kaibo Xia ◽

Sukai Zhu ◽

...

Keyword(s):

Pulsed Laser ◽

Laser Drilling ◽

High Quality ◽

Ultrasound Assisted

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Hollow Carbon Fiber Decorated by Nano Structure Surface for High‐Efficiency Water Steam Generation

Advanced Sustainable Systems ◽

10.1002/adsu.202100122 ◽

2021 ◽

pp. 2100122

Author(s):

Xidong Suo ◽

Jie Yang ◽

Yanrong Zhang ◽

Yuting Hao ◽

Jiahui Yang ◽

...

Keyword(s):

Carbon Fiber ◽

High Efficiency ◽

Steam Generation ◽

Nano Structure ◽

Water Steam ◽

Structure Surface ◽

Hollow Carbon

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An Underwater Image Enhancement Algorithm Based on Generative Adversarial Network and Natural Image Quality Evaluation Index

Journal of Marine Science and Engineering ◽

10.3390/jmse9070691 ◽

2021 ◽

Vol 9 (7) ◽

pp. 691

Author(s):

Kai Hu ◽

Yanwen Zhang ◽

Chenghang Weng ◽

Pengsheng Wang ◽

Zhiliang Deng ◽

...

Keyword(s):

Image Quality ◽

Image Enhancement ◽

Quality Evaluation ◽

High Efficiency ◽

Natural Image ◽

High Quality ◽

Generative Adversarial Network ◽

Image Quality Evaluation ◽

Adversarial Network ◽

Underwater Image

When underwater vehicles work, underwater images are often absorbed by light and scattered and diffused by floating objects, which leads to the degradation of underwater images. The generative adversarial network (GAN) is widely used in underwater image enhancement tasks because it can complete image-style conversions with high efficiency and high quality. Although the GAN converts low-quality underwater images into high-quality underwater images (truth images), the dataset of truth images also affects high-quality underwater images. However, an underwater truth image lacks underwater image enhancement, which leads to a poor effect of the generated image. Thus, this paper proposes to add the natural image quality evaluation (NIQE) index to the GAN to provide generated images with higher contrast and make them more in line with the perception of the human eye, and at the same time, grant generated images a better effect than the truth images set by the existing dataset. In this paper, several groups of experiments are compared, and through the subjective evaluation and objective evaluation indicators, it is verified that the enhanced image of this algorithm is better than the truth image set by the existing dataset.

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