|
|
Testing of Solders in Protection Atmosphere
Vala, Radek ; Jankovský, Jaroslav (referee) ; Szendiuch, Ivan (advisor)
The project deals with the overall design and construction of equipment called the desiccators for brazing in a protective atmosphere. The device was designed and manufactured cooling and heating element. For the soldering various temperature profiles have been defined and adjusted, as for SnPb as well for lead-free solders. There was a realization of samples were measured and analyzed. Finally were realized micro sections for lead free solder.
|
|
|
Creep-fatigue models for solder joints reliability prediction
Novotný, Václav ; Šandera, Josef (referee) ; Švecová, Olga (advisor)
This project is focused on utilization of creep-fatigue models for estimate of reliability lead-free solder joints. It describes basic groups of creep-fatigue models, their usage for estimate of reliability solder joint, advantages and disadvantages. There are discusssed properties of single models, which are on different base. Purpose of this project is find optimal creep-fatigue model for lead-free solder and devise a test structure to which the model will be verified. Results are compared with theoretical calculations.
|
|
|
Machanical testing of solder joints
Drab, Tomáš ; Šandera, Josef (referee) ; Szendiuch, Ivan (advisor)
The project contains theoretical research of electrotechnical manufacture for lead-free reflow soldering. It contains characterization of soldering processes. Includes variations of solder paste printing, principles of part placing and also reflow soldering process. The project appoints possibilities of testing solder joints strength, mainly focused on mechanical vibrations. It describes a design and preparation of solder joint strength test methods by mechanical vibrations. It compares influence of vibrations on part types and solder alloys.
|
|
|
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.
|
|
|
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.
|
|
|
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.
|
|
|
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.
|
|
|
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.
|
|
|
Creep-fatigue models for solder joints reliability prediction
Novotný, Václav ; Šandera, Josef (referee) ; Švecová, Olga (advisor)
This project is focused on utilization of creep-fatigue models for estimate of reliability lead-free solder joints. It describes basic groups of creep-fatigue models, their usage for estimate of reliability solder joint, advantages and disadvantages. There are discusssed properties of single models, which are on different base. Purpose of this project is find optimal creep-fatigue model for lead-free solder and devise a test structure to which the model will be verified. Results are compared with theoretical calculations.
|
|
|
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.
|
guest ::
