Slip Casting of Alumina: Optimizing Rheological and Processing Parameters for High-Density Ceramics

Slip casting is a well-established technique for shaping traditional ceramics, offering high green density, low shrinkage, and effective densification. However, its application in engineering ceramics, particularly alumina, remains limited due to the material’s processing sensitivity and performance demands. This study presents a novel approach by adapting slip castingtypically not used for advanced ceramics- to produce high-density alumina bodies, positioning it as a cost-effective and geometrically versatile alternative to conventional methods such as hot pressing. The research systematically optimizes critical rheological and processing parameters including pH, solid loading, deflocculation, and viscosity. Through precise control of slurry behavior, dense and homogeneous alumina ceramics with hardness values reaching up to 1640 Vickers Pyramid number (HV) were achieved. This work demonstrates that, with appropriate parameter tuning, slip casting can be a viable route for engineering applications of alumina, expanding the potential of this low-cost processing technique. Additionally, the study identifies the detrimental role of iron inclusions, highlighting areas for further refinement in processing quality. Major Findings: The study highlights the critical role of advanced ceramic materials in high-temperature and structural applications due to their exceptional thermal stability, mechanical strength, and corrosion resistance. It identifies key processing techniques such as sintering, coating methods, and the integration of nanomaterials that enhance ceramic performance. The review also emphasizes the growing importance of ceramic composites and surface engineering in expanding industrial applications.