Synthesis and Effect of CaTiO3 formation in CaO·Al2O3 by Solid-State Reaction from CaCO3· Al2O3 and Ti

Abstract

CaO⋅Al2O3/CaTiO3 material was synthesized by a solid-state reaction. The effects of CaTiO3 formed into the CaO⋅Al2O3 during the synthesized process on the microstructure and mechanical properties were studied. CaCO3 was obtained from snail shells, Al2O3, and Ti powders were employed as a raw material. A chemical system with a 1:1 M ratio between CaCO3 and Al2O3 was formed, with an addition of 10 wt% Ti metallic particles. The microstructural analysis through optical microscopy, scanning electron microscopy, and X-ray diffraction was realized. The apparent density was determined by the Archimedes method, and the mechanical behavior (hardness, fracture toughness, and transversal elastic modulus) were also determined. XRD analysis revealed the formation of calcium aluminate phases such as CaAl2O4, CaAl4O7, and CaAl12O19; in addition, the CaTiO3 phase was also identified. The in-situ formation of CaTiO3 in the ceramic material, improves the mechanical properties such as the transversal elastic modulus and fracture toughness (48 GPa and 1.32 MPa m1/2, respectively) in comparison to the reference material (55 GPa and 0.43 MPa m1/2, respectively). Changes in the microstructural morphology, bulk density, and hardness values were also observed with a positive effect in the compound material.