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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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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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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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Analysis of Defects on PCB Using Modern Optical Method
Vala, Martin ; Řezníček, Michal (referee) ; Řihák, Pavel (advisor)
This diploma thesis is focused on detecting of defects on BGA (Ball Grid Array) components using of X-ray. Defects are formed during reflow BGA components during assembly, but also later due to mechanical and thermal stress. Therefore, there is an overview of defects and methods of diagnosis of BGA packages eg .: modern X-ray defect detection or micro sections. There is disclosed a device NORDSON DAGE XD7600NT its operation and setup. The device enables advanced methods of scanning called X-plane. For creating 3D models used reconstructive software called CERA, which uses raw data from the method of X-Plane.
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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
Vala, Martin ; Adámek, Martin (referee) ; Szendiuch, Ivan (advisor)
This thesis examines the influence of nitrogen atmosphere on the quality of the solder joint lead-free solder paste. For the solder paste were measured and set temperature profiles. 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 influence of nitrogen atmosphere. The reliability and the quality of the soldered joints were investigated.
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