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Temperature Profile in Reflow Soldering and Influence of Different PCBś and ComponentsThermal Capacities
Procházka, Martin ; Špinka, Jiří (referee) ; Starý, Jiří (advisor)
This thesis mainly deals with the prediction of temperature on the components and the PCB during reflow soldering. The theoretical part describes the particular solder reflow process, types of heat transfer and temperature profiles. The practical part is divided into forecasting temperatures if the conveyor is stopped and the temperature predictions when the conveyor is in motion. In both parts of the measured temperature is compared with the predicted temperatures, which show the success rate of prediction. The last part of this work is part of the simulation, which helps in proper understanding of the issues discussed.
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Wetting of lead-free solders on ceramic substrates
Lipavský, Lubomír ; Otáhal, Alexandr (referee) ; Adámek, Martin (advisor)
This master's thesis deals with issue of lead-free soldering in protective atmosphere with focus on wetting test. Theorethical part is focused on the types of lead-free solders, wettability tests performed on solder joints, different types of soldering or comparison of influence of the base material in regards to the wetting of the solder. The goal of practical part is testing and comparison of spreadability of selected lead-free solder on two conductive surfaces with different concentration of oxygen in protective nitrogen atmosphere. Testing has been performed on ceramic substrate which differs this method from others, performed on organic substrate. For an over-melted solder, the crystal-growth on surface in regards to protective atmosphere concentration is shown.
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The strength of soldered joints on ceramic substrates
Jansa, Vojtěch ; Nicák, Michal (referee) ; Adámek, Martin (advisor)
This thesis deals with problematic of lead – free soldering and consequent testing of mechanical characteristics of solder joints. The theoretical part is focused on various types of lead – free solders, influence of protective atmosphere on the solders characteristics and mechanical testing of solder joints. Basic materials and thick - films making technology is mentioned. Practical part contains a design of topology that was used for mechanical strength testing of solder joints connecting SMD component and ceramic substrate. Properties of lead – free solder pastes was investigated on various concentrations of O2 and compared with lead soldering paste.
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Temperature Profiles Measurement of BGA Packages in Reflow Soldering
Tomčáková, Anna ; Bureš, Tomáš (referee) ; Starý, Jiří (advisor)
This graduation thesis addresses questions to thermal profile measurement of PBGA package during solder reflow process. The first part of thesis deals with problem of reflow process and reliability factors of solder joint connection. Next part analyses operation principles of thermocouples that are commonly used for temperature measurement. The experimental part deals with methods of thermocouples fixation during tests and measurements of dummy PBGA package. There was realized a method of dummy PBGA thermal profiles measurement and sample testing with and without simulated thermal load on PBGA package. The end of thesis concerns on possibilities of thermal profiles evaluation by using PWI method and thermal profile optimization of reflow process.
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Design of Reflow Soldering Station for Reballing of BGA Packages
Janiš, Adam ; Szendiuch, Ivan (referee) ; Otáhal, Alexandr (advisor)
This thesis deals with the design of a soldering oven for BGA reballing in a nitrogen protective atmosphere. The principles of reflow soldering, the advantages of a nitrogen protective atmosphere on the quality of solder joints and the types of soldering devices are described. The BGA packages´ part consists of their characteristics, assembling methods, a rework and repair process and solder joint inspection methods. Design of the device, as well as heat flow simulations, are included in the experimental part and particularly it also describes the used structural elements and the principle of function of the individual parts of the device. At the end of this work, the soldering process was measured and the ability of the sample soldering was verified.
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Solder Joint Quality based on Heating Factor
Kučírek, Martin ; Špinka, Jiří (referee) ; Starý, Jiří (advisor)
Master’s thesis in the theoretical part analyses the heating factor (Q), which has significant share on quality of a solder joint. The practical part describes the design and production of test PCB and setting temperature profiles, SMD resistors soldering by using BiSn solder paste. Shear tests of SMD solder joints were realised and evaluated including isothermal ageing samples. At the end of master’s thesis solder joints visual aspects and defects were evaluated, measurement thickness of intermetallic compound by not only optical microscope but also SEM, discussion about results and Q was evaluated.
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The comparison of properties of solder joints on ceramic substrates by shear tests
Lipavský, Lubomír ; Schnederle, Petr (referee) ; Adámek, Martin (advisor)
This thesis deals with issues lead – free soldering in a protective atmosphere with a focus on mechanical tests. The theoretical part is focused on the types of lead-free solders, mechanical tests carried on the solder joints and various methods reflow soldering. It is also discussed reliability and durability of solder joints. Aim of the practical part is to compare the strength of solder joints using shear tests for various sizes of components, various concentrations of protective nitrogen atmosphere and various types of solder pastes. Testing is performed on a ceramic substrate, which differs from the works being carried on an organic substrate. For each type of solder paste is further processed by the percentage occurrences of each type tearing of solder joint.
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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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Lead Free Solder Joint Quality based on Heating Factor
Dosedla, Milan ; Zdeněk, Jurčík (referee) ; Starý, Jiří (advisor)
This bachelor’s thesis deals with influence of the heating factor on the quality of lead free solder joints in the reflow soldering process. It summarizes the basic knowledge and some requirements for soldered joints, analyses reflow profiles and presents some of the results published in the literature. Aim of the practical part is by samples soldered with different size of the heating factor determine and evaluate the impact of this factor to the strength and appearance of the final solder joint and the structure and thickness of the intermetallic layers.
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Inspection and optimization of soldering profiles of reflow furnaces
Flos, Milan ; Zatloukal, Miroslav (referee) ; Bača, Petr (advisor)
This thesis is focused on the implementation of solutions for the control of temperature profiles in an industrial environment. The theoretical part deals with the soldering process itself, individual types of soldering and their possible defects. Furthermore, the problem of temperature profiles, their division and the advantages and disadvantages of individual profiles were discussed. Subsequently, the measurement was performed on several remelting furnaces and its evaluation. Lastly, the design of the holder for the profilometer and the PCB itself was created.
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