#TITLE_ALTERNATIVE#

• Main Author: ZULHAZMI (NIM : 13707009); Pembimbing Utama Dr. Ir. Aditianto Ramelan, GHAZI
• Format: Final Project
• Language: Indonesia
• Online Access: https://digilib.itb.ac.id/gdl/view/15769
• Institution: Institut Teknologi Bandung

Alumina (Al2O3) is a ceramic materials that have some excellent properties such as high hardness, good resistivity, resistance to corrosion, and relatively easy in processing. Those properties make it widely used for various applications, such as materials for the spark plug insulators, sanitary ware, crucible, cutting tools, wear components, engine parts, ballistic armor, refractory, even as bioceramic for bone substitute material. Seeing this, increasing in the properties of alumina is required to expand and improve the quality of alumina utilization in the human lives. <br /> <br /> <br /> <br /> <br /> This research aims to see the effect of adding two different types of additives on the shrinkage behavior, hardness, and fracture toughness of alumina ceramic system. Alumina powder used had size about 3 &#956;m with 90% purity. Additives are added in the form of 1 w/o titania (TiO2), 1 w/o magnesia (MgO), titania-magnesia alloys respectively 1 w/o. The process of making sample are powder pressing method, with a compacting pressure of 100 MPa. Sintering is carried out until 1750oC for alumina sample alone and 1550oC to alumina plus additives. Mikrovickers method used for hardness testing. Indentation method used for evaluation of fracture toughness and the measurement with Anstis equation. In 1550oC, Maximum shrinkage percentage owned by the shrinkage of alumina with titania additive which is equal to 16.65%, the addition of magnesia additive i.e. 9.32%, adding both additive gives 15,13%, while the lowest is owned by the system without additive i.e. 7,83%. The highest hardness value obtained on alumina with titania additive which is equal to 1377 VHN. The addition of magnesia gives 432 VHN, addition of both additive gives 614 VHN, while the lowest is owned by alumina without additive i.e. 131 VHN. Fracture toughness (K1C) of alumina without additive is 3.7 MPa.m1/2. Addition of alumina with titania produce the lowest value, 2.9 MPa.m1/2. Addition of magnesia increase the K1C up to 3,9 MPa.m1/2. Addition of both additive produces the highest value, 5.4 MPa.m1/2. This study also observed the microstructure using SEM in the fracture area to support data and analysis of the properties above.