Effects of sintering parameters on the structures of Fe–Cr–Al extruded honeycombs

Pure Fe, Cr and Al powders were used to mix with an additive to prepare a powder-mixed paste. Fe–25Cr–5Al honeycombs were fabricated by extruding the powder-mixed paste, then dried and sintered. The volume shrinkage and the apparent density of extruded honeycombs after drying and sintering were measured. The effect of sintering temperature and time on the volume shrinkage, the apparent density and the structure of honeycombs had been studied. The results show that the volume shrinkage and the apparent density of metallic honeycombs increase with temperature, the volume shrinkage ranging from 25% to 53%, and the apparent density ranging from 1.0 g/cm3 to 1.7 g/cm3. When sintering at 1250 °C, the volume shrinkage and the apparent density of metallic honeycombs increase with time, reach a maximum at 35–40 min, then decrease. The structure of sintered honeycombs consists of α-Fe, Fe–Cr–Al compounds and Al2O3.