Studium sklovitých smaltových povlaků na výrobcích zhotovených metodou Selective Laser Melting

Abstract

The dissertation deals with the experimental study of the influence of surface pretreatment of additively manufactured metal components on the quality of vitreous enamel coating. The main objective of the dissertation was to compare the topography of surfaces with different pretreatments of printed metal components and to compare the possible different mechanical and chemical properties of enamel coatings applied to these surfaces. During the course of the thesis, secondary objectives were gradually developed, leading to a better understanding of the issues and improving the possible repeatability of the whole application process. The thesis is divided into three parts. The first one is the theoretical part, where vitreous enamel coatings, their components, mechanical and chemical properties, enameling technology, the most common defects of vitreous enamel coatings and examples of practical applications are described in detail. In the research part there is also a brief overview of additive technologies with a focus on the Selective Laser Melting (SLM) method. An important part of the dissertation is the detailed methodology of experimental work. The second part of the thesis is devoted to the experimental work, which starts with the characterization of the input materials. The metal powder used for 3D printing, the printed samples are specified, then the particle size distribution of the enamel powder is determined. Then, the parameters and types of pretreatment of the sample surfaces are specified. The next section deals with the analysis and topography of already pretreated samples, the rheology of the enamel suspension and the selection of a suitable enamel powder/water ratio. The last part deals with testing the properties of vitreous enamel coatings. At the end of the work, the achieved results are evaluated and contributions are determined. The most significant contribution to practice is the functional sample of a stirrer produced by 3D printing with vitreous enamel coating, which is one of the output of the disertation.