Production and characterization of CaO ceramics by spark plasma sintering (SPS)

In this study, calcium oxide (CaO) based ceramics, which have potential for high temperature applications, were fabricated by Spark Plasma Sintering (SPS), one of the advanced sintering technologies, and the structural, microstructural and mechanical properties of the samples were systematically investigated. CaO is a suitable ceramic material candidate for various high temperature applications due to its high melting temperature, superior refractory character and chemical stability. However, since it is difficult to obtain compact structures with sufficient density by conventional sintering techniques, the SPS method was used to produce high-density CaO ceramics at lower temperatures and in short times. Within the scope of the study, the sintering process was carried out under different temperature (1500℃, 1550℃, 1600℃, 1650℃), pressure (40 MPa) and dwell time (5 and 10 min.) parameters and optimum sintering conditions were determined. The microstructural properties of the produced ceramics were analysed by Scanning Electron Microscopy (SEM) and the phase compositions were characterised by X-ray Diffraction (XRD). The bulk densities of the samples were calculated by Archimedes' principle. The data obtained revealed that the SPS method is a highly effective method for the rapid, energy efficient and high density production of CaO based ceramics. In this context, the study shows that SPS technique has a high potential in the development of CaO-based ceramics for functional applications. Keywords: CaO, Spark Plasma Sintering (SPS), ceramic, microstructure, characterization, density, XRD, SEM