Artículos de revistas
Ceramic coating for refractories protection against carbon oxidation, Part 1: Protection mechanisms
InterCeram: International Ceramic Review, v. 48, n. 2, p. 84-88, 1999.
Universidade Federal de São Carlos (UFSCar)
Cia. Side-RúRgica Nacional
Universidade Estadual Paulista (UNESP)
For retarding carbon oxidation in refractories during the preheating of metallurgical furnaces, a ceramic coating, made mainly of sodium phosphosilicate and clay was developed. The coating presents high adherence to the substrate with no swelling. The coating was characterized by thermal analysis, X-ray diffraction at room temperature (XRD) and at high temperature (HTXRD), X-ray fluorescence and scanning electronic microscopy (SEM). The glass transition temperature is reached at 800 °C and only glassy phase is observed above this temperature. Thus the mechanism of protection seems to be the formation of a glassy phase on the surface of the refractory, and the coating tends to be more efficient at temperatures higher than 800 °C.