Development of cordierite/mullite composites using industrial wastes

Abstract

1 | INTRODUCTION Cordierite (2MgO•2Al 2 O 3 •5SiO 2) is one of the most important phases of the MgO-SiO 2-Al 2 O 3 system, having a low coefficient of thermal expansion, excellent thermal shock resistance, low dielectric constant, high resistivity, high chemical resistance, high refractoriness, and high mechanical strength. 1-7 Cordierite-based materials are used in various industrial fields in applications such as refractories, heat insulation, filters, membranes, heating elements, microwave and electromagnetic wave absorbers. 8 There are various methods used to synthesize cordierite, among which solid-state reaction, sol-gel, and glass crystallization stand out. 9 Cordierite synthesis by solid-state reaction is considered to be the most widely used in industry due to its simplicity and low cost. 10 Regarding the formation of cordierite by solid-state reaction, some researchers 11 described this reaction as occurring through two well-defined steps. In the first step, cordierite begins to form at 1100°C, between mullite, enstatite, and cristobalite, and reaches a peak at 1275°C. In the second stage, previously formed cordierite reacts through a differential fusion mechanism with enstatite and cristobalite, forming a liquid at around 1330°C to 1355°C. This liquid is made up of eutectic cordierite-enstatite-silica. With increasing temperature, the liquid begins to react with the remaining

Controlling the Thermal Stability of Kyanite-Based Refractory Geopolymers

“…In the case of coarser aggregates (RC4), an evident mass loss of 5.3% was observed ( Figure 1 b). The slight exothermic peak at about 800 °C (RB3) was related to the formation of enstatite and amorphous silicate [ 26 ]. Around 970 °C, the presence of mullite crystals, kalsilite, leucite and spinel could be justified by the appearance of an exothermic phenomena (RB1).…”

Mullite-Based Ceramics from Mining Waste: A Review

“…Recently, Pinheiro de Brito et al [138] reported the synthesis of cordierite-mullite composites, suitable for application as refractory materials, from compositions incorporating kaolin wastes together with talc and magnesium hydroxide wastes. ) as crystalline phases.…”

Fabrication of Large-Area Mullite–Cordierite Composite Substrates for Semiconductor Probe Cards and Enhancement of Their Reliability

“…Cordierite (2MgO•2Al 2 O 3 •5SiO 2 ) is a promising material for the probe card substrate due to its attractive properties, which include high thermal shock resistance, high resistivity, high refractoriness, chemical stability, and low TEC. As a result, cordierite has found widespread use in a variety of applications, including electrical insulators, refractories, filters, membranes, integrated circuit board substrates, and microwaves [5][6][7][8]. However, dense cordierite ceramics are difficult to obtain due to cordierites' narrow sintering temperature and difficulty sintering using the solid-state process [9][10][11].…”