STRUCTURAL APPLICATIONS OF CERAMICS; EFFECT OF MAGNESIA ADDITIVE

Nigeria is a mineral-rich country, from crude oil to natural minerals, despite the abundance, effective utilisation is still a challenge. Kaolin (white China clay) is an essential raw material in ceramics, paper, paint, plastic, and welding electrode industries, but this vital raw material despite its abundance in the country, due to the inability to effectively refine it to the standard requirements for industrial purposes, Nigeria spends around 14.35 million USD annually to meet up with the local demand. This study harnesses the effect of magnesia on this raw material as a ceramic for structural applications using the slip-casting method. Kaolin was analyzed using X-ray fluorescence (XRF), X-ray diffraction (XRD), thermogravimetric analysis (TGA), Fourier Transform Infrared Spectroscopy (FTIR), and Scanning electron microscopy (SEM). The XRF analysis revealed that all samples had SiO 2 (54.41 wt%), Al 2 O 3 (34.05 wt%), and other trace elements as components. Quartz, microcline, and orthoclase were the main mineral phases identified. Sample 30-200 recorded the highest compressive strength (218.MPa) the highest flexural rigidity was observed on sample 15-200, this indicated that higher magnesia composition reduces the compressive and flexural strength of the ceramics. XRF, XRD, and FTIR spectra confirmed the elemental and chemical compositions of the samples, SEM showed the morphology of the structure of the samples; which showed that when the percentage of magnesia (MgO) was increased from 10 to 60%, the void spaces in the samples increases. TGA analysis explored the relationship between %mass loss and temperature variation of the ceramic samples.