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Design of an experiment to investigate the influence of mechanical vibrations and electric current during the soldering process
Nohel, David ; Jankovský, Jaroslav (referee) ; Otáhal, Alexandr (advisor)
This bachelor thesis focuses on the investigation of the effects of electrical current and mechanical vibrations on the process of forming a solder joint. The goal was to explore these effects together with the synergy of these two factors and their impact on the mechanical strength and microstructure of solder joints. An experiment was designed and conducted, involving the use of a mechanical vibration device and soldering apparatus with the capability of applying electrical current. The results demonstrated that mechanical vibrations can positively influence the strength of the solder joint, while electrical current significantly affects the structure of intermetallic layers. These findings could contribute to the further development of technologies and materials used in electronic soldering.
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Design of an experiment to investigate the influence of the frequency of mechanical vibrations on the structure of a solder joint
Podolák, Šimon ; Košelová, Zuzana (referee) ; Otáhal, Alexandr (advisor)
The main goal of this bachelor's thesis is to study the influence of vibrations on the structure of solder joints, specifically SAC305 solder paste droplets. The thesis consists of three parts: theoretical, practical, and evaluation of results. The theoretical part focuses primarily on solder joints and the phenomena surrounding them, such as diffusion, voids, crystal morphology, and others. It also describes vibrations and everything related to them, including ultrasound and its use in the field of soldering. The practical part deals with designing workstations for creating individual samples, specifically without vibrations, with 5 kHz vibrations, and with ultrasonic vibrations. This is followed by the process of preparing the samples and modifying them to a state suitable for microscopic examination. The final part involves evaluating the results obtained and comparing the samples with each other.
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Lead-free solder joint and environmental impacts
Kudláček, František ; Zatloukal, Miroslav (referee) ; Starý, Jiří (advisor)
The aim of this bachelor thesis is to determine the effect of low-temperature lead-free solder during the aging process. The theoretical part deals with the types of lead-free solders and solder pastes used for the production of electrical circuits. In the practical part we deal with the design and measurement of the PCB. For our analysis, we pay more attention to the solder paste type Sn42Ag1Bi57 and its temperature profile. A four-point measurement method is used for evaluation, which shows us the difference between the measured values.
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Production process optimization
Habásko, Jakub ; Koška, Petr (referee) ; Fiala, Alois (advisor)
HABÁSKO Jakub: Production process optimization. The Master´s thesis of Master degree, second grade, school year 2008/2009, FME Brno University of Technology, Institute of Metrology and Quality Assurance Testing, October 2009, pages 68, pictures 40, tables 2, supplements 4. The project elaborated in frame of the Master degree, study branch Metrology and Quality Assurance Testing. This Master´s thesis deals with optimization of process plan. In virtue of submission was created an analysis present condition using of statistical methods and it was created suitable statistical methods applicable in production organization. Then is here described the problem of brazing bells, because in this place is originating the most of uptightness. Then the thesis brings recommendation and findings, which can help with optimization this process.
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Structual welding of aluminium alloy
Blahák, Petr ; Hála, Michal (referee) ; Kubíček, Jaroslav (advisor)
The project elaborated in frame of engineering studies branch 2303R002 presents a project that contains welding a structure made of aluminium alloy. There were two usable methods selected, based on literal study of welding aluminium alloys, TIG welding and friction welding, and these were compared with alternative methods of joining, hard soldering and bonding. A work procedure was made for TIG method, soldering and bonding and four experimental joins were made thereafter. Project compares these methods mainly in economical way, also in way of technological difficulties and in way of observance the strength of base materials. Project also deals with problems with lowering strength of base material in heat affected area, burn out of thin material, tendency of aluminium to fill with hydrogen, quick oxidation and consequent hard surface layer emerging on the aluminium.
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Laser brazing in the car industry
Podstavek, Michal ; Mrňa, Libor (referee) ; Kubíček, Jaroslav (advisor)
The project elaborated in frame of engineering studies of the subject M-STG Mechanical Engineering describes elementary methods of joining in the automotive industry. Moreover, it inquires into optimization of laser brazing on the back cover ŠKODA Superb. During the optimization of the process six samples were designed, and the adjustment of the brazing parameters were performed. Consequently, the samples were evaluated by tensile and metallographic tests. Finally, EDS analysis was performed and visual assessment as well.
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Optimization of surface treatment of stainless steels
Mačátová, Lucie ; Žák, Ladislav (referee) ; Kubíček, Jaroslav (advisor)
The project deals with the processes of degreasing industry and testing new laser cleaning process, which has been experimentally verified and tested in the production process. Project also deals with soldering in general as a technology of joining metals. Included are the main components of the soldering, such as solder, flux, the types of connections and their use, ways of soldering and last but not least the soldering corrosion-resistant steel.
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Analysis of Influence of Manufacturing Technology on Utility Properties of a Reducing Valve Part
Novotný, Michal ; Sigmund, Marian (referee) ; Řiháček, Jan (advisor)
The present work is focused on the comparison of the currently used technology for the production of reducing resistors, i.e. electroerosive machining in combination with soldering on one side and the use of a suitable additive technology on the other hand. In addition to the purely technological aspects, such as the individual production processes or their preparation, economic aspects are also compared, supplemented by an assessment of the delivery times of the finished parts. The analysis is carried out The environmental impact of both production approaches is also analysed. The individual comparisons form the basis for to assess whether the replacement of the conventional manufacturing approach by additive manufacturing is advantageous in this case. The results of this assessment can then be used for future applications of the considered additive manufacturing approaches for similar components.
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THE APPLICATION OF NANOMATERIALS FOR LEAD FREE SOLDERS DEVELOPMENT
Pešina, Zbyněk ; Pinkas, Jiří (referee) ; Spousta, Jiří (referee) ; Sopoušek, Jiří (advisor)
The present dissertation is motivated by the search for alternatives of lead-free soldering by nanoparticles of metals and their alloys. The research focuses on the possibility of replacing lead-free solders by nanoparticles. This issue is currently being addressed by the use of lead-free solders but their properties are not entirely equivalent to properties of lead-tin based alloys. The theoretical part of the dissertation first summarizes up-to date knowledge on the development of lead-free alloys currently used for soldering in the electronics. The work compares these lead-free solder candidates with previously used Pb-Sn alloys. The second section of the theoretical part is devoted to nanotechnology that offers possible solutions of problems associated with the use of lead-free solders. The text contains a description of the properties of nanocrystalline materials in comparison with those of compact alloys having the same chemical composition. The possibility of preparation of nanoparticles and potential problems associated with small particle sizes are also presented. Introduction of the experimental part focuses on the preparation of nanoparticles of pure metals and alloys by chemical and physical ways as well as on an instrumentation for characterisation and analysis. Attention is focused on the silver in nanoparticle form that exhibits the low temperature sintering effect, which is thermally activated by decomposition of oxide envelope covering the Ag nanoparticles. This factor is critical for low-temperature sintering and thus also for possible future applications. The thermal effects of the low sintering process were studied by methods of thermal analysis. The preparation of the Cu / Ag nano / Cu joints was carried out in-situ in inert atmosphere and under the action of atmospheric oxygen. In both cases varying conditions of thermal treatment were used. The cross sections of the prepared joints were then used for the metallographic analysis of the local mechanical properties of the resulting silver layer, for the chemical composition evaluation of the resulting layers of the joint, and for the microstructure study. Strength characteristics are represented by testing shear strength of individual joints.
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