#TITLE_ALTERNATIVE#

• Main Author: ANDRIANTO WIBISONO (NIM 13702028), RADEN
• Format: Final Project
• Language: Indonesia
• Online Access: https://digilib.itb.ac.id/gdl/view/11185
• Institution: Institut Teknologi Bandung

In alumina sintering it is common to use magnesia and titania as an additives. These additives will affect the shrinkage and mechanical properties of alumina. The purpose of this research is to study the effect of the addition of magnesia or titania to the firing shrinkage and hardness of alumina. Then the shrinkage will be compared with the Firmandika Harda's (2006) research with the same composition through dry pressing. The alumina specimen in this research were produced through slip casting process with three compositions variation, 100% alumina, alumina with 1% magnesia addition, and alumina with 1% titania addition. The specimens were then fired at 1000oC, 1200oC, 1400oC, and 1600oC. At the end of each firing stage, the specimens were measured for firing shrinkage. Hardness testing, microstructure characterization using Scanning Electron Microscope, and X-Ray Diffraction were done after firing at 1600oC. After firing at 1600oC, the shrinkage of 100% alumina is 4,8% in length, 4,6% in width, and 4,4 % in thickness. The addition of 1% magnesia decrease the shrinkage so it become 3,9% in length, 4% in width, and 3,9 % in thickness. The addition of 1% titania increase the shrinkage so it become 16,8% in length, 16,5% in width, and 19,5 % in thickness. The hardness of the 100% alumina specimens is 215 + 7 VHN, and the specimens with magnesia and titania addition are 128 + 9 VHN and 679 + 93 VHN. For the shrinkage comparison between slip casting with dry pressing, dry pressing's shrinkage (1570oC) in diameter is smaller than slip casting's shrinkage (1600oC) in length and width. Dry pressing's thickness shrinkage (1570oC) is bigger than slip casting's (1600oC) except with the composition with titania addition, this is because there was possibly a springback phenomena in the dry pressing process earlier. <br />