Study on phase behavior and mechanical properties of high temperature resistant materials prepared from waste electric porcelain

In this work, high temperature resistant materials based on waste electrical porcelain were prepared successfully by pressureless sintering method using waste electrical porcelain with different particle sizes, flint clay and dolomite as raw materials. Effects of sintering temperature and different amounts of flint clay on the properties of the prepared high temperature resistant materials were investigated. The analysis of XRD suggested that the temperature promoted the calcium aluminum silicate → gehlenite → anorthite phases transformation, which can also be proved from SEM images. The mechanical properties and volume stability of materials were improved by the formation of a large amount of interwoven plate-like anorthite. Besides, excessive sintering temperature (1300 °C) had adverse effects on microstructure and mechanical properties . The appropriate amount of flint clay additions led to more plate-like anorthite productions. With 30 wt% addition of flint clay, the sample exhibited the optimum comprehensive performance after sintering at 1250 °C showing the highest flexural and compressive strengths of 32.83 MPa and 89.59 MPa. The bulk density and apparent porosity of samples were 2.21 g/cm 3 and 3.27%, respectively. This study provides an experimental basis for the large-scale high-value utilization and recycling of waste electric porcelain.