Article
Chemistry, Physical
Stefan Rung, Niklas Haecker, Ralf Hellmann
Summary: In this study, a comprehensive investigation on laser ablation and micromachining of alumina using a high-power ultrashort-pulsed laser was conducted. The optimal process strategy was determined and discussed based on the variation of laser parameters such as power, pulse duration, repetition rate, and spatial pulse overlap. The results showed that the highest ablation efficiency and ablation rate were achieved at high repetition rate and short pulse duration, while the surface roughness was predominantly affected by the applied laser fluence.
Article
Materials Science, Coatings & Films
Huanzhen Zhang, Lei Zhang, Gaofu Men, Ning Han, Guohua Cui
Summary: Metal matrix composites are widely used in the aerospace industry due to their lightweight and high strength properties. Laser processing techniques are required to overcome the challenges of conventional methods. This study investigated the surface morphology and element distribution of SiC particle-reinforced Al matrix composites using different pulse fluences of laser irradiation, revealing the behavior of the molten matrix and SiC particles under different conditions.
SURFACE & COATINGS TECHNOLOGY
(2022)
Article
Materials Science, Multidisciplinary
Mahmood Alhajj, S. K. Ghoshal
Summary: To meet the demand for biomedicines, diverse biocompatible nanomaterials with improved physiochemical characteristics were developed. New types of silver-copper nanocomposites (AgCuNCs) with fluorescence and localized surface plasmon resonance absorption were synthesized using pulse laser ablation in liquid (PLAL) method. The structure, morphology, and fluorescence properties of these nanocomposites were customized by adjusting the laser fluence. The nanocomposite made at a laser fluence of 14.15 +/- 0.4 J cm-2 exhibited uniform particle size distribution and high fluorescence quantum yield, making it suitable for improved fluorescence-based drug formulation in biomedical applications.
Article
Optics
Ningqiang Wu, Zhaoyang Zhai, Yahui Cui, Yanchao Zhang, Xiaomin Ji, Ruihua Zhang, Jiao Yan
Summary: This study uses simulation and experimental studies to evaluate the temperature field distribution and process law for the pulsed laser processing of stainless steel. The numerical simulation is based on heat transfer theory and explains the subjective temperature field distribution and change process of the stainless steel surface under the influence of laser. The evolution law of machining morphology and size with various parameters are evaluated to provide theoretical support for high-quality processing of stainless steel by a pulsed laser.
OPTICS AND LASER TECHNOLOGY
(2023)
Article
Optics
Simon Schwarz, Stefan Rung, Cemal Esen, Ralf Hellmann
Summary: Rectangular microchannels with vertical sidewalls in fused silica are fabricated using femtosecond laser backside ablation, allowing for control of channel depth and width through applied fluence and number of scans, with focal position adjustment enabling extension of channel depth. The flexibility of the direct writing process is demonstrated by ablating concentric rings.
Article
Optics
Julia Brand, Andrei Rode, Steve Madden, Alison Wain, Penelope L. King, Ludovic Rapp
Summary: This paper investigates the ultrashort pulsed laser ablation of a high heritage value Australian granite and determines the ablation threshold and efficiency of different mineral components. It is relevant to laser cleaning and maintenance of heritage stone surfaces.
OPTICS AND LASER TECHNOLOGY
(2022)
Article
Engineering, Manufacturing
Julian Zettl, Maximilian Klar, Stefan Rung, Cemal Esen, Ralf Hellmann
Summary: This study presents a comprehensive micromachining investigation of rotationally symmetric parts using femtosecond laser, exploring the influences of different parameters on ablation rate and surface roughness. The research achieved the smallest feasible feature sizes and smoothest surfaces, but encountered limitations due to laser induced periodic surface structures and discussed the variation of fluence on curved surfaces, as well as examined heat input into the material.
JOURNAL OF MANUFACTURING PROCESSES
(2021)
Article
Materials Science, Multidisciplinary
Haruyuki Sakurai, Kuniaki Konishi, Hiroharu Tamaru, Junji Yumoto, Makoto Kuwata-Gonokami
Summary: This study develops a new method for analyzing laser ablation morphology without reducing data, spatially correlating the input beam profile and ablated morphology. It is beneficial for extracting well-studied values and dependencies, as well as probing the spatial independence of the process.
COMMUNICATIONS MATERIALS
(2021)
Article
Chemistry, Physical
Daniel Franz, Tom Haefner, Tim Kunz, Gian-Luca Roth, Stefan Rung, Cemal Esen, Ralf Hellmann
Summary: In this study, a comprehensive investigation on laser percussion microvia drilling of FR-4 printed circuit board material using ultrashort pulse lasers is carried out. The effects of different laser parameters on the quality of microvias are analyzed, and the optimal conditions are identified.
Article
Nanoscience & Nanotechnology
Aisha Saddiqa Ahmed, Daniel Wyn Mueller, Stephanie Bruyere, Anne Holtsch, Frank Mueller, Jenifer Barrirero, Kristina Brix, Sylvie Migot, Ralf Kautenburger, Karin Jacobs, Jean-Francois Pierson, Frank Muecklich
Summary: In recent decades, antibiotic resistance has become a crucial challenge for human health. One potential solution is the use of antibacterial surfaces, such as copper and copper alloys. This study investigates the antibacterial properties of brass with topographic surface functionalization via laser interference patterning. The findings reveal the role of chemical modification in the antimicrobial efficiency of the Cu-based alloy within the superficial layers.
ACS APPLIED MATERIALS & INTERFACES
(2023)
Article
Engineering, Manufacturing
Yangzhi Chen, Yanjie Shao, Xiaoping Xiao
Summary: This research proposes a method that combines analytical and simulation approaches to predict the morphology and surface roughness of aluminum alloy grooves. The method accurately tracks the vapor-liquid interface and predicts the ablative morphology of a single pulse. The influence of molten pool flow on surface morphology is also examined through simulations.
JOURNAL OF MANUFACTURING PROCESSES
(2023)
Article
Materials Science, Multidisciplinary
Andreas Tuennermann, Carsten Momma, Stefan Nolte
Summary: Ultrashort pulse lasers have been widely used in precise micromachining. This article presents a brief perspective on the development of this innovative technology from the 1990s until today.
APPLIED PHYSICS A-MATERIALS SCIENCE & PROCESSING
(2023)
Article
Automation & Control Systems
Zhanfei Zhang, Wenhu Wang, Chengcheng Jun, Ruisong Jiang, Yifeng Xiong, Xiaobing Zhang, Zhong Mao
Summary: This study investigates the ablation efficiency and quality of ultrashort pulsed laser ablation of DD6 single crystal alloy. By analyzing both experimental results and theoretical models, the study reveals the impact of laser parameters on ablation rate and efficiency, and proposes a scanning strategy for high efficiency and quality. Theoretical analysis also explains the material removal mechanism and surface morphology formation under different laser conditions.
INTERNATIONAL JOURNAL OF ADVANCED MANUFACTURING TECHNOLOGY
(2021)
Article
Optics
Lisa Ackermann, Matthias Gehring, Clemens Roider, Kristian Cvecek, Michael Schmidt
Summary: Phase-only beam shaping using a spatial light modulator (SLM) improves precision and efficiency in ultrashort pulsed laser materials processing. Speckle noise can be overcome by adding up multiple spot arrays. Changing the individual spot arrays pulse-by-pulse during material ablation is crucial for achieving a uniform high-quality surface. Dividing the SLM into independent sub-sections and sequentially illuminating the corresponding areas allows for rapid changes without changing phase masks on the SLM.
OPTICS AND LASER TECHNOLOGY
(2023)
Article
Chemistry, Multidisciplinary
Luminita Nicoleta Dumitrescu, Eusebiu-Rosini Ionita, Ruxandra Birjega, Andrada Lazea-Stoyanova, Maria-Daniela Ionita, George Epurescu, Ana-Maria Banici, Simona Brajnicov, Florin Andrei, Andreea Matei
Summary: This study presents the deposition of thin films of lamellar clays using laser techniques, focusing on the optimization of deposition parameters to achieve highly oriented crystalline films. The films were characterized using various techniques and different wetting properties were achieved by adjusting the deposition techniques and parameters.