Effect of Mineral Raw Material Addition on the Properties of Cordierite Based Ceramics

The main purpose of the present study is to produce cordierite ceramics using different (traditional ceramic or pressureless and spark plasma sintering) obtaining processes and mineral raw materials of Latvia (dolomites and clays) as the cheap additives. Starting mixtures were composed of synthetic reagents (MgO and Al(OH)3) with the addition of different dolomites, clay and quartz sand. Powder mixtures were sintered at different temperatures both using pressureless and spark plasma sintering methods. It was stated that secondary crystalline phases like anorthite, spinel, corundum are often present together with a glassy phase and final mixtures determine the properties of the obtained ceramics. Suitable densification levels of investigated compositions were attained using different obtaining methods. Mineralogical composition, microstructure and physical properties were detected using XRD, SEM, water immersion and mechanical strength tests. It was stated that properties of cordierite based ceramics are greatly dependent both on the nature of starting materials and sintering method