National Repository of Grey Literature 198 records found  1 - 10nextend  jump to record: Search took 0.00 seconds. 
The influence of welding parameters on the quality and mechanical properties of the weld joint
Vlach, Jan ; Stejskal, Ondřej (referee) ; Kubíček, Jaroslav (advisor)
The Master´s thesis focuses on the possibilities of using MAG welding on carbon steel 1.1221(C60E) without using preheating. It researches the effect of basic welding parameters on the final characteristics with the goal being to find a welding seam without defects, without using preheating.
Renovation of wood flaker rotor blades by flux cored wires
Soldán, Jan ; Kubíček, Jaroslav (referee) ; Sigmund, Marián (advisor)
The bachelor thesis presents a state of renovation of wood flaker rotor blades by flux cored arc welding. The theoretical part of the thesis presents posssible ways of renovations with materials included. Subsequently, in order to find out, which one of two flux cored electrodes are more suitable for this specific renovation, the experiment was made. The flux cored electrodes were compared in heat input, price, micro and macro structure and final hardness of welded material. Due to very high hardness results, the flux cored electrode named Megafil A760M was chosen to be used in the renovation. At the end of the thesis, the specification of welding process was according to EN ISO 15 609-1 standard.
Application of WC grains by brazing
Izák, Josef ; Kubíček, Jaroslav (referee) ; Sigmund, Marián (advisor)
Bachelor thesis is aimed to assessment condition of brazing component barking plate. Solder contains grains of tungsten carbide is applied on steel due to raise hardness of plate. Applied solder with grains, does not only raise the hardness, but also multiply increase lifetime of plate. Technology, which is used to brazing, is oxy – acetylene flame. It will be examined two type of solder. In the first it is provided optical exam and then destruction exams (micro hardness, macrostructure, microstructure, SEM and EDS analysis). In the end It was proposed qualifications of brazer and exams of brazing join.
Welding of pipes made of CrMo steel
Matějek, Martin ; Sigmund, Marián (referee) ; Kubíček, Jaroslav (advisor)
The aim of this diploma thesis is to compare mechanical properties of welded joints on tubes from 32x2 mm. Tubes are made from 25CrMo4 steel, which is used for production of racing kart chassis. The steel has a tensile strength of Rm = 800 MPa and up to 1200 MPa after refinement. For welding of samples are used technologies MAG and TIG.
CMT advanced application in industrial practice
Šoulák, Petr ; Sigmund, Marián (referee) ; Kubíček, Jaroslav (advisor)
In presented diploma thesis is studied problematics of welding of high strength steels. This work also describes arc welding in protective atmosphere CMT Advanced. In experimental part of this work is CMT Advanced method compared with conventional arc welding in protective atmosphere in shortcut mode used for welding of Hardox 450 and Weldox 700 E. Comparing of mechanical properties of weld material are realized via transverse tensile testing and measuring of microhardness. Macrostructure and microstructure of weld was evaluated too. In the last part of this thesis is a brief economical assessment of both studied methods.
Stick welding carbon and high-alloy steels
Hendrych, Marek ; Vaněk, Mojmír (referee) ; Kubíček, Jaroslav (advisor)
This thesis deals with analysis of manual metal arc welding method or method 111. In the research part of this thesis are discused principles of this method, welding power sources and additional welding material-coated elecrodes. Further the thesis is focused on the weldability of steels, especially carbon steels and austenitic stainless steels. In the experimental part was accomplished measurement of operational characteristics of coated electrods. Measurement was carried out on sample of cabon steel S235JR according to ČSN EN and austenitic stainless steel X5CrNi18-10 accordig to ČSN EN. The evaluation envolves a comparison of the results and their justifications.
Comparison of the welding productivity MAG and FCAW
Kutil, Petr ; Sigmund, Marián (referee) ; Kubíček, Jaroslav (advisor)
This thesis is focused on arc welding with MAG and FCAW methods. The first part contains a brief description of these technologies. Emphasis is laid on the principle of arc welding in active shielding gas and on additional materials, especially on solid and flux-cored tubular wires. The second, experimental part, centres on the comparison of MAG (135) and FCAW (136 and 138) methods in terms of the productivity, costs and, last but not least, the quality of fillet welds made in PF welding position. Based on the calculated and measured figures obtained from the experiment, the most suitable method for the given welding position was chosen.
Study of the influence of process parameters on welding properties of ferritic stainless steel in laser oscillation welding
Křepela, Petr ; Kubíček, Jaroslav (referee) ; Mrňa, Libor (advisor)
The aim of this work was to carry out an experiment to assess the influence of the individual welding parameters in the laser welding method with the beam wobbling on the made weld, respectively. welds. The material which was welded was ferritic stainless steel with the designation 1.4016, which, like all ferritic steels, is susceptible to coarse grains and the resulting brittleness which leads to degradation of the mechanical properties of the weld. The welds were compared to a sample welded without wobbling an between themselves. Unfortunately, however, the evaluation of the test samples did not bring significant differences from laser welding without wobbling, however some changes are evident, such as grain orientation, weld defects, or uniformity of mechanical properties over the weld length, where wobbling frequency is most important. Further research should focus on limiting the porosity at higher wobbling frequencies in the shape of a circle or ellipse.
Study of the influence of process parameters on welding properties of ferritic stainless steel and carbon steel in laser oscillation welding
Rýznarová, Martina ; Kubíček, Jaroslav (referee) ; Mrňa, Libor (advisor)
In the thesis, the influence of the shape of the beam wobbling geometry and the spot vibration frequency on the properties of the heterogeneous weld of X12Cr13 martensitic stainless steel with carbon steel S355MC in laser oscillation welding is investigated. Macroscopic control was performed on the samples, which were focused on weld size and heat affected areas, weld defects, weld shape and cant / drop face and weld joint root. Subsequent microscopic inspection determined both the weld metal structure and the heat affected area and base material. The last was a Vickers microhardness test. Based on the experiment, it was found that the spot process frequency is an important process parameter.
Study of properties of laser welds of Domex 460 MC material using arc preheating
Novotný, Michal ; Kubíček, Jaroslav (referee) ; Mrňa, Libor (advisor)
This diploma thesis deals with weldability of Domex 460 MC material. There are two welding methods and three other welded materials in heterogenous connection which will be researched in this diploma thesis. The welding methods are fiber solid-state laser and a new method of hybrid welding called laser – TIG. The other materials are Domex 700 MC, S355J2 and DC01. Domex 460 MC is a high-strenght steel with fine-grained structure. During the welding process the imput heat decreases mechanical properties of the materials. This effect is caused by material seeds growing. From these samples (which were produced by welding) were created metallographic cuts. These metallographic cuts were analysed focusing on their makrostructure, microstructure, mikrohardnest and Mn arrangement in welded heterogenous samples using electron microscope and EDX analysis.

National Repository of Grey Literature : 198 records found   1 - 10nextend  jump to record:
See also: similar author names
1 Kubíček, J.
20 Kubíček, Jan
9 Kubíček, Jaromír
3 Kubíček, Jindřich
1 Kubíček, Jiří
1 Kubíček, Josef
1 Kubíček, Jovan
20 Kubíček, Ján
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