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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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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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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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Visual comparison of lead-free connections for different material combinations
Šula, Matěj ; Starý, Jiří (referee) ; Schnederle, Petr (advisor)
Bachelors thesis describes problems soldering process. It summarizes the knowledge from soldering process, lead-free alloys and solder joint visual testing. The paper compares the influence of protective nitrogen atmosphere to the visual properties of lead-free solders for different base materials. It focuses mainly on assessment of the quality of solder joints in accordance with global standards IPC-A-610.The work includes the recommendations of material combinations.
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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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Investigation of Reliability for Solder Joints in Nitrogen Atmosphere
Šefara, Petr ; Otáhal, Alexandr (referee) ; Szendiuch, Ivan (advisor)
This thesis examines the inuence of nitrogen atmosphere on the quality of the solder joint lead-free solder paste. For the solder paste were measured and set temperature proles. Thesis includes the implementation and measurement of samples in a protective nitrogen atmosphere and without a protective atmosphere. These measurements are compared, and the conclusions were drawn for the inuence of nitrogen atmosphere. The reliability and the quality of the soldered joints were investigated.
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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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Research of the Quality of Solder Joints by BGA and QFN Packages
Otáhal, Alexandr ; Adámek, Martin (referee) ; Szendiuch, Ivan (advisor)
This diplomas thesis deals with specific technologies and manufacture of BGA and QFN packages. Also summarizes the most used test methods for assessing the reliability for. Describes the making of equipment for soldering in a nitrogen atmosphere, followed by comparison solder joints of BGA and QFN forming in different atmosphere. Finally, summarizes knowledge about the process of soldering and desoldering lead-free solders for BGA packages, followed by experimental evaluation of the causes of malfunction of repaired samples.
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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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