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TY - THES AU - Hellmann, Kirsten TI - Anwendungsorientierte Glasentwicklung am Beispiel des Systems CaO-Al<sub>2</sub>O<sub>3</sub>-SiO<sub>2</sub>. PB - Rheinisch-Westfälische Technische Hochschule Aachen VL - Dissertation CY - Aachen M1 - RWTH-2016-09866 SP - 1 Online-Ressource (viii, 106 Seiten) : Illustrationen, Diagramme PY - 2016 N1 - Veröffentlicht auf dem Publikationsserver der RWTH Aachen University 2017 N1 - Dissertation, Rheinisch-Westfälische Technische Hochschule Aachen, 2016 AB - Glass fibers are a product with a high potential for development. Regarding process temperatures, mechanical properties or corrosion resistance there are several approaches for optimization, which can be realized successfully by changes in the glass composition. The focus of this work is on the application of fibers as reinforcement; the matrix material may be either plastics or concrete. Considering some parameters, such as a low liquidus temperature, a high modulus of elasticity or alkaline resistance, suitable and processable glass compositions based on the system CaO-SiO2-Al2O3 can be identified via thermodynamic calculations. Therefore, in a first step, the commercial software FactSageTM is used and the theory of crystalline reference phases of inorganic glasses is taken into account. This theory makes use of the fact that it is possible to find similar structural units in the short-range order of a glass like in a crystal. Thus, complex multi-component glasses can be described and some of their properties can be predicted. In this work, the equilibrium of ternary and quaternary oxide compositions is investigated, which is related to the determination of the corresponding liquidus temperature. In the context of fiber production this temperature and the viscosity become important, since fiberization of a glass melt can be successful only if the drawing temperature is higher than the liquidus temperature. After the phasetheoretical predevelopment the glasses were screened practically and relevant properties were determined.The investigated ternary glasses (sample code CAS) could be processed into fibers having promising mechanical properties. This is of great importance for the use in fiber reinforced plastics, because in this case structural elements can be realized, which can withstand greater loads. The tensile strength of the fibers is comparable with commercial fiber glasses, as well as the modulus of elasticity with values in the range of 86 to 88 GPa. The process temperatures vary between 1120 and 1230 °C. This can save energy costs due to the comparatively low drawing temperatures as well as the inexpensive raw materials. The service life of Pt-bushings can be also extended considerably.By the use of glass fibers in a concrete matrix, smaller, and more filigree structural elements can be realized. The challenge consists in the requirement that the glasses remain stable in the strong alkaline environment. So far, so-called alkali-resistant glasses (AR-glass) containing up to 20 LB - PUB:(DE-HGF)11 UR - https://publications.rwth-aachen.de/record/675154 ER -