REACTIVE COATING OF MAGNETITE BY A PBO-B2O3-SIO2 GLASS

The wetting behaviour of a PbO-B2O3-SiO2 glass on a pure magnetite sub strate was studied in air and CO2 atmosphere from room temperature to 600 degrees C. The decrease in contact angle observed at 590 degrees C was explained by considering the formation of an oxidized layer (simi lar to 20 mu m) during the wetting experiment. The final coating was p roved to be free of cracks due to the small residual stress at the int erface because of the low thermal expansion mismatch. (C) 1996 Elsevie r Science Limited.