STUDY OF FREEZE CASTING PROCESS AND MANUFACTURING OF COLUMNAR ALUMINA THROUGH FREEZE CASTING MANUFACTURING PROCESS

• Main Author: Andika Bangun, Deri
• Format: Theses
• Language: Indonesia
• Online Access: https://digilib.itb.ac.id/gdl/view/54521
• Institution: Institut Teknologi Bandung

The freeze casting manufacturing process is a process that utilizes the growth of ice solids that have dendritic columnar morphology to produce materials that have columnar morphology from materials in the form of a mixture of micro- to nano-sized particles, and a solvent that becomes frozen crystals with a columnar structure. In this study, a literature study was carried out on research that has been carried out reviewing current research up to the past 15 years to conclude areas that have the potential for the freeze casting process and designing a freeze casting apparatus to produce samples with columnar ice morphology. This tool’s design is realized by making a simple freeze casting tool whose main component consists of a cold finger made of copper, a mold made of Teflon, and a cooling agent in the form of liquid nitrogen. Furthermore, using this tool, samples were made using alumina material mixed with a binder in PEG and PVA. The alumina powder size was previously characterized using SEM to determine the alumina powder in the ideal powder size criteria for the freeze casting process. Accordingly, the alumina sample that has been prepared is a mixture of alumina with PEG weight percent of 6wt%, and PVA of 3wt%, 2.25wt%, 1.50wt%, and 0.75wt%. The powder characterization results show that the alumina size is 16,355 ?m, which is smaller than the ideal maximum diameter of alumina for the freeze casting process of 73.54 ?m. The freeze casting results on the alumina sample mixed with binder and water with PVA composition with weight percent (wt%) of the solution were 2.25wt%, 1.50wt%, and 0.75wt% with the characteristics of the distance between the lamellae respectively 58.67 ?m, 126.67 ?m, 84.29 ?m.