Author: Juan Pablo Calderón Urbina Publisher: Springer Nature ISBN: 3662618869 Category : Technology & Engineering Languages : en Pages : 231
Book Description
Ultra-short pulse laser processing of ultra-hard materials requires an accurate and agile experimental and analytical investigation to determine an efficient choice of parameters and settings to optimize ablation. Therefore, this work presents a quality-oriented experimental approach and an analytical approach for the modeling and validation of multi-pulse picosecond laser beam ablation on cemented tungsten carbide. This work starts with a review of literature and state-of-the-art theories of four relevant areas for this research: picosecond lasers, laser beam ablation process, cemented tungsten carbide (WC) and quality-oriented tools. Subsequently, a concept for an efficient material laser beam ablation with a picosecond laser was introduced. Furthermore, two approaches for the investigation are presented from an experimental and analytical perspective, respectively. The first approach introduced a methodology for the identification of influential parameters. It executes a quality-oriented methodology based on the SWOT analysis, cause-and-effect diagram and the variable search methodology. The conclusion of the methodology gave the interaction of pulse repetition rate and scanner speed in the form of pulse overlap and track overlap PO/TO as the most influential parameter in the maximization of the ablation rate. The second most influential factors resulted laser beam power and burst-mode. The second approach, description of the model, executes a theoretical analysis of the picosecond laser beam ablation of cemented WC by the application of the Beer-Lambert law and multi-pulse ablation modeling. The unavailable material properties were obtained by experimental investigations, like in the cases of the incubation factor and the reflectivity factor. Threshold fluence for cemented WC was determined by the application of the heat transfer theory and input power intensity was adapted to a Gaussian beam profile. At the end of the approach, power density visualizations of a picosecond laser pulse under the five available pulse repetition rates were modeled and validated. The findings from the adaptation of the Beer-Lambert law acted as basis for development of the multi-pulse laser ablation model for both single-pulse mode and burst-mode, respectively. Based on the definition of the number of pulses N irradiating the same area, the corresponding threshold fluence for N, the input fluence and incubation factor, ablation depth was modeled and experimentally validated. Finally, results and conclusions of both approaches were discussed and a framework for an efficient laser beam ablation was presented. Recommendations for further actions on research and industry were introduced at the end of the work.
Author: Juan Pablo Calderón Urbina Publisher: ISBN: 9783662618875 Category : Languages : en Pages : 0
Book Description
The development of ultra-short pulse lasers has given laser beam ablation a wider application perspective by granting minimal thermal side-effects, industrial robustness and precision. A rising field of opportunity is the processing of ultra-hard materials. The intersection of reliable ultra-short pulse laser sources and the increasing trend of hardness represents an opportunity for laser beam ablation. This thesis describes the modeling and validation of multi-pulse picosecond laser beam ablation on cemented tungsten carbide (WC) to enable the identification of optimized parameter settings for an efficient ablation process. Thus, a quality-oriented experimental approach based on the variable search methodology was chosen. Within the multi-pulse laser beam ablation model, the Beer-Lambert law, heat transfer fundamentals, incubation and laser burst-mode are considered to accurately describe the process. Content A concise journey through the background and understanding of ultra-short pulse laser technologies Offers versatile application of quality-oriented tools in laser beam material processing Describes a single-pulse and multi-pulse model on cemented tungsten carbide capable to be adapted to other materials and laser systems The author Juan Pablo Calderón Urbina obtained his Bachelor's degree in Industrial Engineering at the Morelia Institute of Technology in Morelia, Mexico (Instituto Tecnológico de Morelia). He specialized in International Production Management at the Hamburg University of Technology (Technische Universität Hamburg) for his Master of Science's degree. Until 2013, he collaborated as a research assistant in several research and industrial projects with the Laser Zentrum Nord GmbH. In 2019, he concluded his scientific research and completed his doctorate at the Hamburg University of Technology, in the Institute of Laser and System Technologies (Institut für Laser- und Anlagensystemtechnik, iLAS).
Author: Dmitriy Mikhaylov Publisher: Cuvillier Verlag ISBN: 3736964463 Category : Technology & Engineering Languages : en Pages : 176
Book Description
High precision, high quality, and high throughput of ultrashort pulse laser ablation of bulk material are the most demanded properties that are required to let this process technology compete with other micro-machining techniques. Previous attempts to increase volumetric ablation rates of ultrashort pulse laser processes were based on the increase of fluence or pulse repetition rates. They run into limitations mainly set by the occurrence of bumpy surfaces due to overheating of bulk material. In this work, the potential of laser beam shaping for the enhancement of ablation rates is studied systematically for the first time. The question regarding the physically shortest possible process time for ablation of 2.5D-structures by means of an ultrashort pulse laser is answered using a heat conduction model, which is extended by the ability to consider spatially shaped beams. The strategy of laser beam stamping is implemented in a novel optical setup and proven both theoretically and experimentally to have a great potential for increasing ablation rates.
Author: Peter Hannaford Publisher: Springer Science & Business Media ISBN: 038723294X Category : Science Languages : en Pages : 350
Book Description
The embryonic development of femtoscience stems from advances made in the generation of ultrashort laser pulses. Beginning with mode-locking of glass lasers in the 1960s, the development of dye lasers brought the pulse width down from picoseconds to femtoseconds. The breakthrough in solid state laser pulse generation provided the current reliable table-top laser systems capable of average power of about 1 watt, and peak power density of easily watts per square centimeter, with pulse widths in the range of four to eight femtoseconds. Pulses with peak power density reaching watts per square centimeter have been achieved in laboratory settings and, more recently, pulses of sub-femtosecond duration have been successfully generated. As concepts and methodologies have evolved over the past two decades, the realm of ultrafast science has become vast and exciting and has impacted many areas of chemistry, biology and physics, and other fields such as materials science, electrical engineering, and optical communication. In molecular science the explosive growth of this research is for fundamental reasons. In femtochemistry and femtobiology chemical bonds form and break on the femtosecond time scale, and on this scale of time we can freeze the transition states at configurations never before seen. Even for n- reactive physical changes one is observing the most elementary of molecular processes. On a time scale shorter than the vibrational and rotational periods the ensemble behaves coherently as a single-molecule trajectory.
Author: Guowei Yang Publisher: CRC Press ISBN: 9814241520 Category : Science Languages : en Pages : 1166
Book Description
This book focuses on the fundamental concepts and physical and chemical aspects of pulsed laser ablation of solid targets in liquid environments and its applications in the preparation of nanomaterials and fabrication of nanostructures. The areas of focus include basic thermodynamic and kinetic processes of laser ablation in liquids, and its applic
Author: Dongfang Yang Publisher: BoD – Books on Demand ISBN: 9535128116 Category : Technology & Engineering Languages : en Pages : 430
Book Description
Laser ablation refers to the phenomenon in which a low wavelength and short pulse (ns-fs) duration of laser beam irradiates the surface of a target to induce instant local vaporization of the target material generating a plasma plume consisting of photons, electrons, ions, atoms, molecules, clusters, and liquid or solid particles. This book covers various aspects of using laser ablation phenomenon for material processing including laser ablation applied for the deposition of thin films, for the synthesis of nanomaterials, and for the chemical compositional analysis and surface modification of materials. Through the 18 chapters written by experts from international scientific community, the reader will have access to the most recent research and development findings on laser ablation through original research studies and literature reviews.
Author: Nicola Cioffi Publisher: Springer Science & Business Media ISBN: 3642244270 Category : Technology & Engineering Languages : en Pages : 563
Book Description
There is a high demand for antimicrobials for the treatment of new and emerging microbial diseases. In particular, microbes developing multidrug resistance have created a pressing need to search for a new generation of antimicrobial agents, which are effective, safe and can be used for the cure of multidrug-resistant microbial infections. Nano-antimicrobials offer effective solutions for these challenges; the details of these new technologies are presented here. The book includes chapters by an international team of experts. Chemical, physical, electrochemical, photochemical and mechanical methods of synthesis are covered. Moreover, biological synthesis using microbes, an option that is both eco-friendly and economically viable, is presented. The antimicrobial potential of different nanoparticles is also covered, bioactivity mechanisms are elaborated on, and several applications are reviewed in separate sections. Lastly, the toxicology of nano-antimicrobials is briefly assessed.
Author: Leon J. Radziemski Publisher: CRC Press ISBN: 1000147371 Category : Technology & Engineering Languages : en Pages : 476
Book Description
This book discusses the physics of plasma initiation and reviews the features of dissipating, propagating plasmas. It deals with advances in diagnostics for high-energy, laser-fusion plasmas. The book reviews the basic physical processes, plasma characteristics of the "continuous optical discharge".
Author: Koji Sugioka Publisher: Springer ISBN: 3642105238 Category : Science Languages : en Pages : 353
Book Description
Miniaturization and high precision are rapidly becoming a requirement for many industrial processes and products. As a result, there is greater interest in the use of laser microfabrication technology to achieve these goals. This book composed of 16 chapters covers all the topics of laser precision processing from fundamental aspects to industrial applications to both inorganic and biological materials. It reviews the sate of the art of research and technological development in the area of laser processing.
Author: William M. Steen Publisher: Springer Science & Business Media ISBN: 1447137523 Category : Technology & Engineering Languages : en Pages : 416
Book Description
New chapters on bending and cleaning reflect the changes in the field since the last edition, completing the range of practical knowledge about the processes possible with lasers already familiar to users of this well-known text. Professor Steen's lively presentation is supported by a number of original cartoons by Patrick Wright and Noel Ford, which will bring a smile to your face and ease the learning process. From the reviews: "...well organized, and the text is very practical...The engineering community will find this book informative and useful." (OPTICS AND PHOTONICS NEWS, July/August 2005)
Author: Juan Pablo Calderón Urbina
Author: Juan Pablo Calderón Urbina
Author: Dmitriy Mikhaylov
Author: Peter Hannaford
Author: Guowei Yang
Author: Dongfang Yang
Author: Nicola Cioffi
Author: Leon J. Radziemski
Author: Koji Sugioka
Author: William M. Steen