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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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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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HAL Technology and Selected Parameters Influence on Quality
Jakub, Miroslav ; Jana, Toulová (referee) ; Starý, Jiří (advisor)
Bachelor thesis describes and deals the problems of printed circuit boards production. It focuses on issues of process of lead – free HAL and influence of selected parameters on quality in production process GATEMA s.r.o. in Boskovice. Bachelor thesis contains analysis of PCB using microsection, optical microscopy and a sample of defects created during this process. Bachelor thesis presents on the test boards quality of solder mask developing, evaluates flux contamination with water, residual water on the PCB and it compares the PCB delay in liquid solder. It also determines the limit of non defective cover with the solder and determines the typical thickness of solder mask on the Cu pads and the ratio between the width of font and solder mask thickness.
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PCBs Cleaning Process Optimization
Smejkal, Jakub ; Tichopádek, Petr (referee) ; Starý, Jiří (advisor)
The diploma thesis introduces readers to the issue of PCB cleanliness by a short analysis of historical approaches to their cleaning. The theoretical part defines what phenomena occur in case of leaving impurities on the PCB and names the different types of impurities with a focus on fluxes. It also deals with types of cleaning fluids and selected technologies suitable for PCB cleaning, including research of specific products and their manufacturers. The practical part analyses the current state of washing processes in the company TESCAN Brno, s.r.o and performs the initial cleanliness test of PCBs from external suppliers and internally assembled PCBs. Based on the performed analysis, the work then focuses on the replacement of the current cleaning fluid and the optimization of the used solder. In connection with the process and results of a series of test measurements performed in both monitored areas, work proposes a methodology for evaluating the current applicability of the cleaning liquid and for testing the surface insulation resistance.
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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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Influence of fluxes on weld metal properties
Holub, Kamil ; Sigmund, Marian (referee) ; Kubíček, Jaroslav (advisor)
This thesis deals with the topic of submerged arc welding – an electric arc method of fusion welding, that uses a layer of granulated flux to shield the weld pool from atmospheric gases. Theoretical part is devoted to the description of the welding method and fluxes currently used. The practical part contains an experiment, which consists of making two weld deposits on structural steel S235JR by using different fluxes. First weld deposit is made with OK 10.62 Flux. The same flux alloyed with the Tribaloy T-800 laser cladding powder is used for the second weld deposit. Test specimens are examined on the basis of influence of fluxes combined with a single electrode wire.
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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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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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