Sintering Behavior, Thermal Expansion, and Environmental Impacts Accompanying Materials of the Al₂O₃/ZrO₂ System...

This work focuses on research on obtaining and characterizing Al₂O₃/ZrO₂ materials formed via slip casting method. The main emphasis in the research was placed on environmental aspects and those related to the practical use of ceramic materials. The goal was to analyze the environmental loads associated with the manufacturing of Al₂O₃/ZrO₂ composites, as well as to determine the coefficient of thermal expansion of the obtained materials, classified as technical ceramics. This parameter is crucial in terms of their practical applications in high-temperature working conditions, e.g., as parts of industrial machines. The study reports on the four series of Al₂O₃/ZrO₂ materials differing in the volume content of ZrO₂. The sintering process was preceded by thermogravimetric measurements. The fabricated and sintered materials were characterized by dilatometric study, scanning electron microscopy, X-ray diffraction, and stereological analysis. Further, life cycle assessment was supplied. Based on dilatometric tests, it was observed that Al₂O₃/ZrO₂ composites show a higher coefficient of thermal expansion than that resulting from the content of individual phases. The results of the life cycle analysis showed that the environmental loads (carbon footprint) resulting from the acquisition and processing of raw materials necessary for the production of sinters from Al₂O₃ and ZrO₂ are comparable to those associated with the production of plastic products such as polypropylene or polyvinyl chloride.