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The analysis of Cu-Sn-Sb ternary alloy
Kučera, Jan ; Doubrava, Marek (referee) ; Jan, Vít (advisor)
This bacholor thesis deals with substituting silver-based material, currently used for experimental semi-liquid extrusion. The proposed material is from the Cu-Sb-Sn system. The theoretical part of the work deals with soldering and phase diagrams. The experimental part is devoted to the analysis of three proposed alloys from the Cu-Sb-Sn system, their structural and mechanical properties. Thermal analyzes of the alloys were performed using differential scanning calorimetry (DSC), the microstructure using a light microscope and a scanning electron microscope, and a hardness tester was also used to determine the hardness. The results are summarized in the discussion.
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Optimalization of soldering process on IR-400
Otáhal, Alexandr ; Nicák, Michal (referee) ; Szendiuch, Ivan (advisor)
This project deals with innovation of IR-400 equipment which is based on design and installation of temperature regulation, in both top and bottom side. This innovation enables adjustment of reflow temperature profile for repair and rework of SMD components by lead-free solder materials for both, FR4 and alumina substrates, as assembly of some special packages.
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Reliability of Lead-free Solders and the Selected Methods to Estimate its Lifetime
Švecová, Olga ; Kolařík, Vladimír (referee) ; Urbánek,, Jan (referee) ; Šandera, Josef (advisor)
The doctoral thesis is focused on reliability of lead-free solder SAC 305. Knowledge in the field of fatigue models used in determining the lifetime of solder joints are observed in this thesis. Also such methods of predicting reliability as numerically-analytical methods or reliability experimental tests are mentioned. Practical results of reliability measurement are presented. Experimental data served as the foundation for determining empirical coefficients for the fatigue model based on deformation induced by creep of the solder, which was implemented in the ANSYS environment. Results from different methods were compared and conclusions discussing the suitability of the presented prediction methods are formulated.
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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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Optimizing of QFN Package Assembly Process
Šváb, Martin ; Jankovský, Jaroslav (referee) ; Szendiuch, Ivan (advisor)
The Master thesis deals with technology of mounting QFN packages on to the printed circuits boards. Describes also influence of shape and size of soldering pads and the amount of soldering paste with respect to the quality and the reliability. In first part overview of existing packages is summarised. Second part describes design of testing board and the factors which leads to eliminating errors during manufacturing process.
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Termomechanical reliability soldered connections in electronic
Novotný, Václav ; Psota, Boleslav (referee) ; Šandera, Josef (advisor)
The diploma thesis deals with the sphere of solder joints reliability. The narrower focus is use of lead-free solder alloy SAC305 in the production process and parameters of its reliability. The text describes the main factors, which have the influence on the reliability of solder joints under conditions of thermal cycling. These factors also relate with choice of substrates and technological processes of preparation, which are characterized and described. Another part is devoted to estimating the reliability of soldered connections and are listed the fatigue model to estimate reliability. These fatigue models are categorized based on different physical mechanisms that operate in the soldered joints during operation. Based on the comparison of different models is selected the most appropriate model and in conjunction with simulation in ANSYS is estimated reliability. For this purpose is selected soldered connection of the FR-4 substrate and ceramic substrate via SMD component. They are manufactured test kits and subjected to conditions of temperature cycling. Results obtained from experimental measurements are compared with results obtained by simulation and calculation.
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Lead-Free solder thermal and microstructure analysis
Klepárníková, Eliška ; Molliková, Eva (referee) ; Jan, Vít (advisor)
The bachelor thesis deals with Ag-Sn-Sb system, construction of pseudobinary diagram 90An10Sb – 90Sn10Sb and construction of ternary diagram at 20 C. The theoretical part deals with soldering, phase diagrams and methodics of determination of phase diagrams. The experimental part is focused on describing the creation of five alloys and their further exploration. Alloy analyzes were performed by differential scanning calorimetry (DSC), light microscope and scanning electron microscope. Results from these thermal and microstructural analyzes were processed into the resulting pseudobinary and ternary diagram.
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The possibilities of SMD components soldering by equipment Fritsch
Juračka, Martin ; Šandera, Josef (referee) ; Adámek, Martin (advisor)
This thesis focuses on soldering technology in microelectronics. It describes in detail the basic ways of soldering and repairs in electronics. This piece of work shows the principles of technological equipment for bulk soldering and used repairing devices. In the theoretical part of this work there are also briefly described the packages for integrated circuits that were used in the practical part of the thesis. The practical part of the thesis deals with setting of the heat profiles for hot air repair station Fritsch Mikroplacer for LQFP64, SOIC16, TSSOP14, QFN16 and DSBGA5 packages. The heat profiles for assembly and disassembly of the particular types of the packages on designed and manufactured test printed circuit board were set and tested. The resulting heat profiles are compared with the recommended heat profile of an ordinary solder paste SnAg3Cu0,5 which was used for the test. This thesis can serve as an aid for the further settings of heat profiles in other types of packages not only on Fritsch Mikroplacer devices, but also on other repairing devices of this type.
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Optimalization of repair process in Surface Mount Technology
Vala, Radek ; Řezníček, Michal (referee) ; Szendiuch, Ivan (advisor)
This project deals with utilizing of IR 400 equipment for assembly and repair of SMD components soldered by lead-free solder materials. The part of the work concerns with optimizing of the temperature profile, which is very important in the repair to eliminate the damage of components and PCB. There was added controller R 500 and cooling equipment to allow better control of the temperature during the soldering cycle.
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Manual Soldering Station - Evaluation of Selected Parameters
Němec, Ivo ; Špinka, Jiří (referee) ; Starý, Jiří (advisor)
This semestral work deals with the investigation of different principles of heating elements control in soldering stations and the influence of lead-free solder alloy on the life of soldering tips. The thesis summarizes the description of the sub-elements of the soldering stations and explains their functions. The defects of the soldering tips due to the use of lead-free solder alloys are also described. Last but not least, European directives governing the use of lead-free solder alloys in electronic and electrical products are mentioned.
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