• Refine Query
  • Source
  • Publication year
  • to
  • Language
  • 3
  • 3
  • Tagged with
  • 7
  • 7
  • 4
  • 4
  • 4
  • 3
  • 3
  • 3
  • 3
  • 3
  • 3
  • 3
  • 3
  • 3
  • 3
  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

Characterization and improvement of copper/glass adhesion

He, Baofeng January 2012 (has links)
The development of glass substrates for use as an alternative to printed circuit boards (PCBs) attracts significant industrial attention, because of the potential for low cost but high performance interconnects and optical connection. Electroless plating is currently used to deposit conductive tracks on glass substrates and the quality of copper / glass adhesion is a key functional issue. Without adequate adhesive strength the copper plating will prematurely fail. Existing studies have covered the relationship between surface roughness and adhesion performance, but few of them have considered the detail of surface topography in any depth. This research is specifically considering the mechanical contribution of the glass surface texture to the copper / glass adhesive bond, and attempting to isolate new ISO 25178 areal surface texture parameters that can describe these surfaces. Excimer laser machining has been developed and used to create a range of micro pattern structured surfaces on CMG glass substrates. Excimer mask dimensions and laser operation parameters have been varied and optimized according to surface topography and adhesion performance of the samples. Non-contact surface measurement equipment (Zygo NewView 5000 coherence scanning interferometry) has been utilized to measure and parameterize (ISO 25178) the surface texture of the glass substrates before electroless copper metallization. Copper adhesion quality has been tested using quantitative scratch testing techniques, providing an identification of the critical load of failure for different plated substrates. This research is establishing the statistical quality of correlation between the critical load values and the associated areal parameters. In this thesis, the optimal laser processing parameter settings for CMG glass substrate machining and the topographic images of structured surfaces for achieving strong copper / glass plating adhesion are identified. The experimental relationships between critical load and areal surface parameters, as well as the discussions of a theoretical approach are presented. It is more significant to consider Sq, Sdq, Sdr, Sxp, Vv, Vmc and Vvc to describe glass substrate surface topography and the recommended data value ranges for each parameter have been identified to predict copper / plating adhesion performance.
2

Mechanical durability of hydrophobic surfaces fabricated by injection moulding of laser-induced textures

Romano, J.-M., Gulcur, Mert, Garcia-Giron, A., Martinez-Solanas, E., Whiteside, Benjamin R., Dimov, S.S. 23 January 2020 (has links)
Yes / The paper reports an investigation on the mechanical durability of textured thermoplastic surfaces together with their respective wetting properties. A range of laser-induced topographies with different aspect ratios from micro to nanoscale were fabricated on tool steel inserts using an ultrashort pulsed near infrared laser. Then, through micro-injection moulding the topographies were replicated onto polypropylene surfaces and their durability was studied systematically. In particular, the evolution of topographies on textured thermoplastic surfaces together with their wetting properties were investigated after undergoing a controlled mechanical abrasion, i.e. reciprocating dry and wet cleaning cycles. The obtained empirical data was used both to study the effects of cleaning cycles and also to identify cleaning procedures with a minimal impact on textured thermoplastic surfaces and their respective wetting properties. In addition, the use of 3D areal parameters that are standardised and could be obtained readily with any state-of-the-art surface characterisation system are discussed for monitoring the surfaces’ functional response. / The full-text of this article will be released for public view at the end of the publisher embargo on 23 Jan 2020.
3

Mechanical durability of hydrophobic surfaces fabricated by injection moulding of laser-induced textures

Romano, J.-M., Gülçür, Mert,, Garcia-Giron, A., Martinez-Solanas, E., Whiteside, Benjamin R., Dimov, S.S. 22 January 2019 (has links)
Yes / The paper reports an investigation on the mechanical durability of textured thermoplastic surfaces together with their respective wetting properties. A range of laser-induced topographies with different aspect ratios from micro to nanoscale were fabricated on tool steel inserts using an ultrashort pulsed near infrared laser. Then, through micro-injection moulding the topographies were replicated onto polypropylene surfaces and their durability was studied systematically. In particular, the evolution of topographies on textured thermoplastic surfaces together with their wetting properties were investigated after undergoing a controlled mechanical abrasion, i.e. reciprocating dry and wet cleaning cycles. The obtained empirical data was used both to study the effects of cleaning cycles and also to identify cleaning procedures with a minimal impact on textured thermoplastic surfaces and their respective wetting properties. In addition, the use of 3D areal parameters that are standardised and could be obtained readily with any state-of-the-art surface characterisation system are discussed for monitoring the surfaces' functional response. / European Commission H2020 ITN programme “European ESRs Network on Short Pulsed Laser Micro/Nanostructuring of Surfaces for Improved Functional Applications” (Laser4Fun) under the Marie Skłodowska-Curie grant agreement No. 675063 (www.laser4fun.eu) and the UKIERI DST programme “Surface functionalisation for food, packaging, and healthcare applications”. In addition, the work was supported by three other H2020 programmes, i.e. the projects on “Modular laser based additive manufacturing platform for large scale industrial applications” (MAESTRO), “High-Impact Injection Moulding Platform for mass-production of 3D and/or large micro-structured surfaces with Antimicrobial, Self-cleaning, Anti-scratch, Anti-squeak and Aesthetic functionalities” (HIMALAIA) and “Process Fingerprint for Zero-defect Net-shape Micromanufacturing” (MICROMAN).
4

Thin-wall injection molding of polystyrene parts with coated and uncoated cavities

Masato, Davide, Sorgato, M., Babenko, Maksims, Whiteside, Benjamin R., Lucchetta, G. 29 December 2017 (has links)
Yes / The paper reports an investigation on the mechanical durability of textured thermoplastic surfaces together with their respective wetting properties. A range of laser-induced topographies with different aspect ratios from micro to nanoscale were fabricated on tool steel inserts using an ultrashort pulsed near infrared laser. Then, through micro-injection moulding the topographies were replicated onto polypropylene surfaces and their durability was studied systematically. In particular, the evolution of topographies on textured thermoplastic surfaces together with their wetting properties were investigated after undergoing a controlled mechanical abrasion, i.e. reciprocating dry and wet cleaning cycles. The obtained empirical data was used both to study the effects of cleaning cycles and also to identify cleaning procedures with a minimal impact on textured thermoplastic surfaces and their respective wetting properties. In addition, the use of 3D areal parameters that are standardised and could be obtained readily with any state-of-the-art surface characterisation system are discussed for monitoring the surfaces' functional response.
5

Kalibrace koherenčního rastrovacího interferometru Talysurf CCI / Calibration of Talysurf CCI coherence scanning interferometer

Varava, Anastasia January 2017 (has links)
This master’s thesis deals with calibration of a coherence scanning interferometer Talysurf CCI Lite. Basic terms related to surface texture evaluation were described along with selected profile and areal surface texture parameters. The working principle and design of the calibrated instrument were explained. Manufacturer’s calibration procedure was analyzed in relation to the definition of calibration in the International vocabulary of metrology. Further calibration steps leading to calculation of measurement uncertainty were presented. Last but not least, measurement uncertainties of areal surface texture parameters Sq and Sz were evaluated. The procedures and results described in this thesis may contribute to wider use of non-contact surface texture measuring instruments.
6

Využití parametrů textury povrchu pro posuzování shody a řízení procesu / Use of Surface Texture Parameters for Conformity Assessment and Process Control

Špačková, Magda January 2018 (has links)
This master‘s thesis deals with using surface texture parameters for conformity assessment and process control. The aim of the thesis was to create an overview of surface texture parameters, an overview of procedures for conformity assessment and process control using surface texture parameters, practical application on an industrial product and practical recommendations. The thesis includes an overview of profile and areal surface texture parameters, including an original translation of terms of the areal method. Methods of conformity assessment and process control in connection with the surface texture parameters are also described. Statistical analysis was performed based on 7200 values of surface parameters and 1843200 values of profile parameters which were measured on parts from serial production. The last chapter includes practical recommendations.
7

Pokročilé metody vyhodnocování topografie povrchu součásti / Advanced methods of surface topography evaluation

Šindelka, Marek January 2019 (has links)
This thesis focuses on a measuring and topography of a components´ surface evaluation and it contains the overview of basic methods which includes the description of contact and non-contact measuring devices. Furthermore, the thesis also describes ways of surface texture evaluation through profiled and areal method, including an outline of ČSN ISO parameters. The practical part of the thesis focuses on the evaluation of metric threads´ M10 surface, crafted by diverse cutting and forming threads. The surface was scanned with the optical device called Alicona IFM G5 and it was evaluated through the profiled and areal method. The 2D and 3D parameters were acquired and then compared during the measuring.

Page generated in 0.0863 seconds