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Abstract

The rebuilding technologies are used to develop surface of ladle. Among many welding methods currently used to obtain surface layer without defects one of the most effective way of rebuilding is using metal arc welding. This additional material gives more possibilities to make expected quality of rebuild surface. Chemical composition, property and economic factors allow to use metal wire. Because of these reasons, solid wire gives opportunity to be wildly used as material to rebuild or repair the surface in different sectors of industry. The paper shows a few ways to rebuild the surface in the massive cast with the use of metal active gas welding for repair. The work presents studies of defect in the massive cast. It contains the pictures of microstructures and defects. The method of removing defects and the results of checking by visual and penetrant testing methods are shown. The paper describes the methodology of repair the ladle with metal active gas welding, preheating process and standards nondestructive testing method.
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Abstract

The paper analyzes, from the geometrical aspect, the quality of the new flux cored wire intended for cladding process in function of changes in cladding parameters such as welding speed, coefficient of thermal conductivity, power source setting, the length of projecting portion of the electrode. The results of bead geometry analysis allows to illustrate the nature of the impact of the examined input variables on parameters of generated surface. The most important parameters here are the depth of penetration and the height of clad. The experimental data were processed using the Plackett-Burman experiment, which describes the impact of technological parameters on the main parameters used during production of resisting panels. It shows mathematical relations describing correlations between the input parameters and the value of depth of penetration and hight of bead made by Flux Cored Arc Welding (FCAW).
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Abstract

The surfacing technologies are used for constitution of protection layer against wear and is destined for obtaining coating with high hardness. Among many weldings methods currently used to obtain the hard surface layer one of the most effective way of hardfacing is using flux cored arc welding. This additional material gives more possibilities to make expected hard surface layer. Chemical composition, property and economic factors obtained in flux cored wire are much richer in comparison to these obtained with other additional materials. This is the reason why flux cored wires give possibilities of application this kind of material for improving surface in different sectors of industry. In the present paper the imperfection in the layers was used for hardfacing process in different situations to show the possible application in the surface layer. The work presents studies of imperfection of the welds, contains the picture of microstructures, macrostructures and shows the results of checking by visual and penetrant testing methods.
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Abstract

The paper presents the capabilities of welding techniques to creating properties of wear resistant high chromium cast iron alloy. The use of the right kind of welding sequence allows you to change the structure and properties of the obtained welds. Tests were conducted for one type of additive material in the form of self shielded core wire. In order to determine the effect of the type of welding sequence on the properties of welds performed welding using string bead and weave bead. The resulting weld was tested on hardness and research structure in an optical microscope. In the following studies have been made erosive tests wear of made hardfacing. String beads gave structure rich in carbides and harder about 270 HV of the weld with weave bead. Also, wear resistance was nearly twice as better for welds made with string beads. In the experiment a decisive role in the resistance to wear plays a high hardness of the deposit and the presence of carbides in its structure. Changes in the basic parameters of the deposition process allows for the formation of structure and properties of hardfacing welds in a wide range.
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Abstract

The welding technologies are widely used for design of protection layer against wear and corrosion. Hardfacing, which is destined for obtaining coatings with high hardness, takes special place in these technologies. One of the most effective way of hardfacing is using self shielded flux cored arc welding (FCAW-S). Chemical composition obtained in flux cored wire is much more rich in comparison to this obtained in solid wire. The filling in flux cored wires can be enriched for example with the mixture of hard particles or phases with specified ratio, which is not possible for solid wires. This is the reason why flux cored wires give various possibilities of application of this kind of filler material for improving surface in mining industry, processing of minerals, energetic etc. In the present paper the high chromium and niobium flux cored wire was used for hardfacing process with similar heat input. The work presents studies of microstructures of obtained coatings and hardness and geometric properties of them. The structural studies were made with using optical microscopy and X- ray diffraction that allowed for identification of carbides and other phases obtained in the structures of deposited materials. Investigated samples exhibit differences in coating structures made with the same heat input 4,08 kJ/mm. There are differences in size, shape and distribution of primary and eutectic carbides in structure. These differences cause significant changes in hardness of investigated coatings.
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