東華大學圖書館 |

Role of Machining Parameters and Post-Processing Steps on the Surface Elemental Composition of Femtosecond Laser-Machined Copper Surfaces.

Record Type:	Electronic resources : Monograph/item
Title/Author:	Role of Machining Parameters and Post-Processing Steps on the Surface Elemental Composition of Femtosecond Laser-Machined Copper Surfaces./
Author:	Joy, Nithin.
Published:	Ann Arbor : ProQuest Dissertations & Theses, : 2023,
Description:	176 p.
Notes:	Source: Dissertations Abstracts International, Volume: 85-11, Section: B.
Contained By:	Dissertations Abstracts International85-11B.
Subject:	Photographs. -
Online resource:	https://pqdd.sinica.edu.tw/twdaoapp/servlet/advanced?query=31079024
ISBN:	9798382617923

Role of Machining Parameters and Post-Processing Steps on the Surface Elemental Composition of Femtosecond Laser-Machined Copper Surfaces.
Joy, Nithin.

Role of Machining Parameters and Post-Processing Steps on the Surface Elemental Composition of Femtosecond Laser-Machined Copper Surfaces. - Ann Arbor : ProQuest Dissertations & Theses, 2023 - 176 p.

Source: Dissertations Abstracts International, Volume: 85-11, Section: B.

Thesis (Ph.D.)--McGill University (Canada), 2023.

Over the past few decades, short/ultra-short pulsed laser micro/nano-machining has emerged as a versatile technique in efficiently tailoring the properties of metallic surfaces for numerous applications. Progress in laser machining of metallic surfaces has prompted the importance of controlling the surface elemental composition. These investigations highlighted the transition of surface chemistry over time upon exposure to various conditions and proposed different mechanisms as explanations for the observed evolution. Nevertheless, previous studies conducted laser machining and subsequent exposures under uncontrolled conditions with minimum data stated about the specific working condition were subject to uncertainty. This PhD thesis aims to provide a thorough insight into identifying the individual effects of various machining parameters and post-processing steps that contribute to the final surface chemistry.The thesis begins with a comprehensive review of how surface chemistry contributes to the transition in the wetting response of laser-machined surfaces, summarizes the controversies, and emphasizes the existing gaps in knowledge. Further, we hypothesized that the laser machining in an inert atmosphere led to more reactive sites for further reaction, and the presence of water molecules significantly impacts the kinetics of the surface chemistry transition.The proposed hypothesis was tested on a polished copper substrate, and all experiments were accomplished without exposure to uncontrolled conditions until the surface chemistry analysis was completed. The experiments found that the surface laser-machined in an inert atmosphere, such as Ar, resulted in minimum C/Cu and O/Cu ratios indicating a high number of reactive sites for further reactions. We note the significance of the presence of water molecules in the machining and exposure environments on the modification of surface elemental composition. We found that exposing laser-machined samples to carbon dioxide contributed insignificantly to carbonaceous layer adsorption, while acetylene was effective for quickly depolarizing the surface. Additionally, we show that the surface carbon content of laser-machined samples is maximized by immersing them in a lauric acid-ethanol solution.In the next step, we shifted our focus from surface chemistry experiments to developing an in situ method for collecting nanoparticles (NPs) during femtosecond laser machining, thus providing an outlook on circular waste-free laser processes. We show that laser machining in the presence of an applied electric field or floating potential is a promising technique for collecting the generated NPs. Qualitatively, the collection efficiency depends on the laser scanning directions. As collection efficiency depends on electrical properties, the introduced technique fits metals and semiconductors. Furthermore, we found that laser machining under a floating potential or applied field did not appear to affect the resulting laser-induced structures.Next, we carefully probed how re-deposited NPs affect the surface chemistry of laser-machined surfaces. Compared to the clean laser-induced periodic surface structures, the laser-machined sample with re-deposited NPs has a significantly altered surface chemistry. Additionally, we validate that the ultrasonication of laser-machined samples in ethanol substantially affects the final surface elemental composition. In summary, our results demonstrate that laser machining, preprocessing, and postprocessing steps strongly affect the reproducibility of a sample's desired properties. It is, therefore, imperative that these steps be reported with extreme diligence. Lastly, we characterized the NPs collected using our in situ collection setup. The copper NPs dispersed in ethanol showed remarkable stability confirming the efficacy of the established waste-free laser machining process.

ISBN: 9798382617923Subjects--Topical Terms:

627415
Photographs.

Role of Machining Parameters and Post-Processing Steps on the Surface Elemental Composition of Femtosecond Laser-Machined Copper Surfaces.
LDR:09080nmm a2200385 4500 001 2402193
005 20241028051452.5
006 m o d
007 cr#unu||||||||
008 251215s2023 ||||||||||||||||| ||eng d
020 $a 9798382617923
035 $a (MiAaPQ)AAI31079024
035 $a (MiAaPQ)McGill_vq27zt521
035 $a AAI31079024
035 $a 2402193
040 $a MiAaPQ $c MiAaPQ
100 1 $a Joy, Nithin. $3 3772416
245 1 0 $a Role of Machining Parameters and Post-Processing Steps on the Surface Elemental Composition of Femtosecond Laser-Machined Copper Surfaces.
260 1 $a Ann Arbor : $b ProQuest Dissertations & Theses, $c 2023
300 $a 176 p.
500 $a Source: Dissertations Abstracts International, Volume: 85-11, Section: B.
500 $a Advisor: Kietzig, Anne-Marie.
502 $a Thesis (Ph.D.)--McGill University (Canada), 2023.
520 $a Over the past few decades, short/ultra-short pulsed laser micro/nano-machining has emerged as a versatile technique in efficiently tailoring the properties of metallic surfaces for numerous applications. Progress in laser machining of metallic surfaces has prompted the importance of controlling the surface elemental composition. These investigations highlighted the transition of surface chemistry over time upon exposure to various conditions and proposed different mechanisms as explanations for the observed evolution. Nevertheless, previous studies conducted laser machining and subsequent exposures under uncontrolled conditions with minimum data stated about the specific working condition were subject to uncertainty. This PhD thesis aims to provide a thorough insight into identifying the individual effects of various machining parameters and post-processing steps that contribute to the final surface chemistry.The thesis begins with a comprehensive review of how surface chemistry contributes to the transition in the wetting response of laser-machined surfaces, summarizes the controversies, and emphasizes the existing gaps in knowledge. Further, we hypothesized that the laser machining in an inert atmosphere led to more reactive sites for further reaction, and the presence of water molecules significantly impacts the kinetics of the surface chemistry transition.The proposed hypothesis was tested on a polished copper substrate, and all experiments were accomplished without exposure to uncontrolled conditions until the surface chemistry analysis was completed. The experiments found that the surface laser-machined in an inert atmosphere, such as Ar, resulted in minimum C/Cu and O/Cu ratios indicating a high number of reactive sites for further reactions. We note the significance of the presence of water molecules in the machining and exposure environments on the modification of surface elemental composition. We found that exposing laser-machined samples to carbon dioxide contributed insignificantly to carbonaceous layer adsorption, while acetylene was effective for quickly depolarizing the surface. Additionally, we show that the surface carbon content of laser-machined samples is maximized by immersing them in a lauric acid-ethanol solution.In the next step, we shifted our focus from surface chemistry experiments to developing an in situ method for collecting nanoparticles (NPs) during femtosecond laser machining, thus providing an outlook on circular waste-free laser processes. We show that laser machining in the presence of an applied electric field or floating potential is a promising technique for collecting the generated NPs. Qualitatively, the collection efficiency depends on the laser scanning directions. As collection efficiency depends on electrical properties, the introduced technique fits metals and semiconductors. Furthermore, we found that laser machining under a floating potential or applied field did not appear to affect the resulting laser-induced structures.Next, we carefully probed how re-deposited NPs affect the surface chemistry of laser-machined surfaces. Compared to the clean laser-induced periodic surface structures, the laser-machined sample with re-deposited NPs has a significantly altered surface chemistry. Additionally, we validate that the ultrasonication of laser-machined samples in ethanol substantially affects the final surface elemental composition. In summary, our results demonstrate that laser machining, preprocessing, and postprocessing steps strongly affect the reproducibility of a sample's desired properties. It is, therefore, imperative that these steps be reported with extreme diligence. Lastly, we characterized the NPs collected using our in situ collection setup. The copper NPs dispersed in ethanol showed remarkable stability confirming the efficacy of the established waste-free laser machining process.
520 $a Au cours des dernieres decennies, le micro/nano usinage par laser a impulsions courtes/ultra-courtes s'est impose comme une technique polyvalente permettant d'adapter efficacement les proprietes des surfaces metalliques a de nombreuses applications. Les progres realises dans l'usinage laser des surfaces metalliques ont mis en evidence l'importance du controle de la composition elementaire de la surface. Ces etudes ont mis en evidence la transition de la chimie de surface dans le temps apres exposition a diverses conditions et ont propose differents mecanismes pour expliquer l'evolution observee. Neanmoins, les etudes precedentes ont effectue l'usinage laser et les expositions subsequentes dans des conditions non controlees avec un minimum de donnees sur les conditions de travail specifiques, ce qui est sujet a l'incertitude. Cette these de doctorat vise a fournir un apercu approfondi de l'identification des effets individuels des differents parametres d'usinage et des etapes de post-traitement qui contribuent a la chimie de la surface finale.La these commence par un examen complet de la facon dont la chimie de surface contribue a la transition dans la reponse de mouillage des surfaces usinees au laser, resume les controverses et met l'accent sur les lacunes existantes dans les connaissances. En outre, nous avons emis l'hypothese que l'usinage au laser dans une atmosphere inerte conduisait a des sites plus reactifs pour une reaction ulterieure, et que la presence de molecules d'eau avait un impact significatif sur la cinetique de la transition de la chimie de surface.L'hypothese proposee a ete testee sur un substrat de cuivre poli, et toutes les experiences ont ete realisees sans exposition a des conditions non controlees jusqu'a ce que l'analyse de la chimie de surface soit terminee. Les experiences ont montre que la surface usinee au laser dans une atmosphere inerte, telle que l'Ar, presentait des rapports C/Cu et O/Cu minimaux, ce qui indique un nombre eleve de sites reactifs pour d'autres reactions. Nous notons l'importance de la presence de molecules d'eau dans les environnements d'usinage et d'exposition sur la modification de la composition elementaire de la surface. Nous avons constate que l'exposition au dioxyde de carbone d'echantillons usines au laser contribuait de maniere non significative a l'adsorption de couches carbonees, tandis que l'acetylene etait efficace pour depolariser rapidement la surface. En outre, nous montrons que la teneur en carbone de la surface des echantillons usines au laser est maximisee lorsque immergee dans une solution d'acide laurique et d'ethanol.Dans l'etape suivante, nous transitionnons des experiences de chimie de surface vers le developpement d'une methode in situ pour collecter les nanoparticules pendant l'usinage par laser femtoseconde, offrant ainsi une perspective sur les processus laser circulaires sans dechets. Nous montrons que l'usinage laser en presence d'un champ electrique applique ou d'un potentiel flottant est une technique prometteuse pour collecter les nanoparticules generees. D'un point de vue qualitatif, l'efficacite de la collecte depend des directions de balayage du laser. Comme l'efficacite de la collecte depend des proprietes electriques, la technique introduite convient aux metaux et aux semi-conducteurs. En outre, nous avons constate que l'usinage au laser sous un potentiel flottant ou un champ applique ne semblait pas affecter les structures resultantes.Ensuite, nous avons soigneusement examine comment les nanoparticules redeposees affectent la chimie de surface des pieces usinees au laser. Compare aux structures de surface periodiques propres induites par le laser, l'echantillon usine au laser avec des nanoparticules redeposees presente une chimie de surface significativement alteree. En outre, nous validons que l'ultrasonication des echantillons usines au laser dans l'ethanol affecte considerablement la composition elementaire de la surface finale.
590 $a School code: 0781.
650 4 $a Photographs. $3 627415
650 4 $a Surface chemistry. $3 551428
650 4 $a Nanoparticles. $3 605747
650 4 $a Lasers. $3 535503
650 4 $a Electric fields. $3 880423
650 4 $a Aluminum. $3 735071
650 4 $a Copper. $3 1070053
650 4 $a Hydrophobic surfaces. $3 714069
650 4 $a Contact angle. $3 3320098
650 4 $a Electromagnetics. $3 3173223
650 4 $a Mechanical engineering. $3 649730
650 4 $a Nanotechnology. $3 526235
650 4 $a Optics. $3 517925
650 4 $a Chemistry. $3 516420
690 $a 0607
690 $a 0548
690 $a 0652
690 $a 0752
690 $a 0485
710 2 $a McGill University (Canada). $3 1018122
773 0 $t Dissertations Abstracts International $g 85-11B.
790 $a 0781
791 $a Ph.D.
792 $a 2023
793 $a English
856 4 0 $u https://pqdd.sinica.edu.tw/twdaoapp/servlet/advanced?query=31079024