Phase Composition and Physico-Mechanical Properties at Different Firing Temperatures of Ceramic Earthquake-Resistant Bricks with the Use of Ferro-Dust

Abstract

Ceramic bricks based on low-melting clay and ferro-dust from self-disintegrating, low-carbon, ferrochrome slags, graded from M100 to M175, respectively, were obtained in the temperature range 950 -1100°C. The highest grades are in bricks fired at the temperatures 1050 and 1100°C, respectively, M150 and M175, which can be used as earthquake-resistant. Studies have shown that hematite, wollastonite, diopside and a liquid phase appear at brick firing temperature 950°C. Raising the firing temperature to 1000°C contributes to the appearance of anorthite and cristobalite. Raising the firing temperature to 1050°C does not bring about any special changes, except for an increase in the content of cristobalite and anorthite and a decrease in the content of feldspar. Subsequent raising of the firing temperature to 1100°C results in higher content of anorthite, diopside and cristobalite. The physicomechanical indicators increase due to the formation of anorthite and diopside in the samples.

Newly Generated Ca-Feldspar during Sintering Processes Enhances the Mechanical Strength of Coal Gangue-Based Insulation Bricks

“…After sintering, a new crystalline Ca-feldspar substance (Figure 3a,b) appeared in the insulation brick, and this was because SiO 2 and Al 2 O 3 in gangue, K-feldspar and fly ash melted into the glassy phase under high temperatures, reacting with CaO and producing Ca-feldspar. Ca-feldspar is a kind of plagioclase with a molecular formula of CaAl 2 Si 2 O 8 , and it generally exists in nonmetallic stable phases [26]. The SEM-EDS image of K15-Ca10 treatment (Figure 4) showed that four elements, Si, Al, O and Ca, are located basically in the same position, which further supports the existence of Ca-feldspar.…”