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Analysis of Aplication Flux and Solder Paste on PCB for BGA components
Toufar, Michal ; Řihák, Pavel (referee) ; Vala, Radek (advisor)
This thesis deals with rework of BGA components. There are described defects and errors in a solder joints. The current trend is focused on thin packages with fine pitch. It is assembled with smaller and smaller solder balls. It is described effect of different application of flux and solders paste for rework. The main part is focused on dipping and dispensing. These methods are suitable for repair process.
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Influence of printed board surface finishing on solderability with vapour soldering
Matras, Jan ; Starý, Jiří (referee) ; Šandera, Josef (advisor)
Thesis deals with vapor soldering and wetting the surface with solder during the soldering process. It describes in detail the advantages and disadvantages of various surface finishes on the PCB. Generally characterizes the properties of lead-free solders and fluxes. Describes vapor soldering process, including the properties of the liquid itself. It also focuses on a method of evaluating the wettability by using solder balls and its performance on individual samples surface finishes.
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Immersion Tin Surface Finish of PCB
Karzel, Vítězslav ; Zatloukal, Miroslav (referee) ; Starý, Jiří (advisor)
The aim of this work is to study and more deeply understand everything about surface finishing of the printed circuit boards, that are used for lead-free soldering. Mainly we should focus on immersion tin and prepare some fundamental information for future measurement. Therefore, in the first part of the thesis is our main task is to create a~sufficient theoretical background for printed circuit boards, immersion tin and solderability. Then we are able to use previously created theoretical background to measure selected samples. Thereafter the measured data can be used for more strict evaluation, from which the results of measurement can be obtained.
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SMD Rework station
Szabó, Michal ; Roubal, Zdeněk (referee) ; Szabó, Zoltán (advisor)
This thesis describes the theory of solder joint and conditions under which it is formed correctly. Further, methods of hand soldering are discussed, and possibilities of temperature regulation of soldering tip are analyzed. Methods of creating a soldering station and its key features are depicted. In practical part, the solution of how to create a soldering station with soldering iron, desolder gun and heatgun is given and is constructed. While testing a defect is found that prevents the power portion of soldering station to function properly and prevents completion.
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Flux Residues after Reflow Soldering
Uhlář, Vít ; Špinka, Jiří (referee) ; Starý, Jiří (advisor)
The aim of this bachelor thesis is to solve flux residue characteristics on PCBś after reflow soldering and compare different solder pastes. The first part deals with the issue of solder paste application and flux residues. The second part focuses on the process of reflow soldering. The third part is devoted to the measurement methodology of flux residues. Finally, project is a practical part, which is summarized in the production of test samples and contains measurement results.
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Flux Selection for Wave Soldering
Dyntarová, Markéta ; Jan, Čermák (referee) ; Starý, Jiří (advisor)
The theoretical part of diploma thesis „Selection of a suitable type of flux for wave soldering”, is devoted to problematic of fluxes, flux residues and wave soldering. It introduces reader with requirements of company HC electronics and with selection of a suitable types of fluxes for testing. It also contains theoretical comparison and design of flux testing methodologies. The practical part of the diploma thesis is focused on the selection of a suitable flux for the company HC electronics by performing practical tests according to the previously proposed methodologies, which include wetting balance test method, surface insulation resistance measurement, copper mirror test, soldering test of PCB and ROSE method.
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Electromigration of Flux Residues on PCB Surface
Tylich, Ondřej ; Zatloukal, Miroslav (referee) ; Starý, Jiří (advisor)
Diploma thesis introduces the problems of electromigration, fluxes and flux residues. It includes a proposal for methods of measuring surface insulation resistance, information about selected types of fluxes and conformal coatings. It focuses on the influence of temperature, humidity. There are applied conductometric method and method of measuring SIR by IPC-25-B. The thesis describes the practical measurement of SIR and ionic contamination of PCB covered with flux and influence of RH, temperature and applied voltage is evaluated and discussed.
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Lead-Free Voids Cause Mechanisms and Influence on Reliability
Šimon, Vojtěch ; Špinka, Jiří (referee) ; Starý, Jiří (advisor)
The aim of this work is to analyze reliability of lead-free solder join, in particular the voids generated during the soldering process. The main target of the theoretical part of the work is to isolate basic mechanisms of formation of the voids and optimize the soldering process. The practical part of the paper is based on monitoring the count and size of the voids in a solder join. An X-Ray tomograph has been chosen as a non-destructive method of detection. The statistical part of this work compares conventional soldering of the entire board with local soldering by IR radiation.
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Optimization of Gases Flow in Exhaust System of Tractor Engine
Létal, Filip ; Svída, David (referee) ; Dundálek, Radim (advisor)
The subject of this thesis is to optimize the flow of exhaust gases in the particle filter using CFD simulations. The first part is focused on the emissions of diesel engines and emissions reduction systems with a focus on particulate filters. The next section is an analysis of the current state of the specified particle filter using CFD simulation and evaluation following with a proposal of new construction for better flow distribution. At last, the final evaluation is presented.
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Solder Wave Process Optimization
Procházka, Martin ; Brno, Martin Štěpánek HONEYWELL (referee) ; Starý, Jiří (advisor)
This work describes solder wave process and it‘s optimalization. It informs us about wave soldering and describes it’s fragments. Next it is described partition of fluxes and their properties. In practical part is described researching of defects on PCB’s and analysis of possible reason of defects, measurement of the weight of sprayed flux and measurement of solderable profile.
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