Kerapatan, Kekerasan dan Koefisien Muai Panas Membran Penghantar Ion Oksigen LaCo 0,8 Fe 0,2 O 3-δ Tersubstitusi Ca 2+ (La 1-x Ca x Co 0,8 Fe 0,2 O 3-δ )

DENSITY, HARDNESSAND THERMAL EXPANSION COEFFICIENTOF Ca 2+ - SUBSTITUTED LaCo0.8Fe0.2O3-δ (La1-xCaxCo0,8Fe0,2O3-δ) OXYGEN ION TRANSPORT MEMBRANE. A dense oxygen ion conductive membrane such as LaCo1-yFeyO3 must be hard and has a low thermal expansion coefficient to survive harsh reaction condition in its application. Substitution of La 3+ with Ca 2+ is expected to improve both properties. Ca 2+ substituted LaCo1-yFeyO3 powders were prepared from their respective metal oxides to become La1-xCaxCo0.8Fe0.2O3-δ (LCCF), where 0.1≤x≤0.4, using the solid state method. X-ray diffraction data indicates that the LCCFs are highly crystalized. The LCCF was then made into a membrane by pressing the powder in a stainless steel mold by applying 6 tonnes load for 10 minutes, followed by sintering the product at 1250°C. SEM analysis results showed that the densities of all LCCF membranes are very high. Average hardnesses of LCCF 9182, 8282, 7382 and 6482 membranes, as measured by the Vicker method,are 902.08, 915.42, 1093, and 1178.6 HV, respectively. Thermal expansion tests showed that LCCF 6482 is a membrane with the lowest thermal expansion coefficient. In addition, it is also evident that the higher the number of Ca 2+ substituents, the higher the hardness and the lower the thermal expansion coefficient. Substitution of La 3+ by Ca 2+ produced denser and harder membranes, as well as low thermal expansion coefficient, which are preferable when they are applied as oxygen ion conductive membranes.