| 摘要 |
PURPOSE:To contrive improvement in joining strength and antioxidizing properties and prevention of peeling in use at high temperatures for a long period, by forming the first ceramic layer prepared by calcining inorganic scaly particles on the surface of a binding layer formed by reaction of a metallic oxide film with a silicate. CONSTITUTION:For example, a tubular member 3 made of vermicular cast iron for exhaust system equipment of internal combustion engines is treated with heated steam to form an oxide film on the surface thereof. A silicate binder solution is then applied to the resultant oxide film and dried. The above- mentioned binding layer is subsequently coated with a slurry consisting of inorganic scaly particles consisting of pulverized silas balloons, a silicate binder and aluminum phosphate hardener to form the first antioxidizing ceramic layer 5, which is then cured, dried and calcined to form a binding layer 4 by reaction of the afore-mentioned oxide film with the silicate simultaneously with the calcining of the layer 5. A surface, heat insulating, fire-resisting layer or layer of combination thereof may be formed on the layer 5. |
