Abstract:
The influence in optimization of processing, calcinations and sintering parameter on the physical properties and characteristic of CaCu3Mn4O12 were investigated. The stoichiometric CaCu3Mn4O12 powders were successfully prepared by the citric gel method. Dried gel with three dimension network consisted of molar ratio of [citrates/metallic ion]; 1:2 was formed. The precursor gel formed was calcined and sintered at range 400 °C to 800 °C. A single-phase CaCu3Mn4O12 fairly well densified at relative low temperature under atmospheric sintering condition. FESEM results turned out that CaCu3Mn4O12 powder particle is submicron in size and highly agglomerates due to high calcinations temperature. The smaller particle size with higher grain boundary and less of porosity were found for the sample sintered at 700 °C to 800 °C. The samples show the ‘superparamagnetism’ behavior where the M-H curves are linear with the field and have a smaller value of coercivity at room temperature. Sintering at 800 °C produced the sample with lowest Hc value due to the phenomenon of over grown magnetocrystallites, grain size and grain boundaries.
