Corrosion-inhibited metal-glass

A corrosion-resistant composite material comprises a sintered intimate mixture of powdered metal and glass particles. The term 'glass' includes enamel and the term 'metal' includes alloys. The glass has softening point below the m.p. of the metal and within \sB 100 DEG C. of the sintering temperature of the metal, and is waterleachable at a rate of 50-10,000 p.p.m. of corrosion-inhibiting ions when agitated in the ratio 1 part glass to 2 parts distilled water for 4 hours at room temperature. Corrosion-inhibiting ions include chromate, tungstate, molybdate, nitrite, nitrate, phosphate, ferrate, and silicate. The glass may contain a colourant. The glass may also contain corrosion inhibitors which release corrosion-inhibiting ions concurrently with those released by dissolution of the glass. Metals include Al, Mg, Zn, Fe and Cu. Articles may be made by dry-mixing the glass and metal powders, preferably finer than 100-mesh, U.S.S. sieve, e.g. 5-41 volume % being glass, cold-pressing to obtain a green compact of 90% theoretical density, and sintering e.g. in an Ar/H2 atmosphere. The hot sintered composite may be mechanically worked, e.g. by forging, rolling or extrusion. Al-glass articles may be etched in 2% NaOH to provide a matte finish. The bodies may be enamelled, and the material may be used as an undercoat for enamelling. Multilayered structures may be made ranging from metal to pure glass with intervening gradations of metal-glass composites.ALSO:A corrosion-resistant composite material comprises a sintered intimate mixture of powdered metal and glass particles. The term "glass" includes enamel and the term "metal" includes alloys. The glass has softening point below the M.P. of the metal and within \sB100 DEG C. of the sintering temperature of the metal, and is water-leachable at a rate of 50-10,000 p.p.m. of corrosion-inhibiting ions when agitated in the ratio 1 part glass to 2 parts distilled water for 4 hours at room temperature. Corrosion-inhibiting ions include chromate, tungstate, molybdate, nitrite, nitrate, phosphate, ferrate, silicate. The glass may contain a colourant. The glass may also contain corrosion inhibitors which release corrosion-inhibiting ions concurrently with those released by dissolution of the glass. Metals include Al, Mg, Zn, Fe and Cu. Articles may be made by dry-mixing the glass and metal powders, preferably finer than 100-mesh, U.S.S. sieve, e.g. 5-41 volume per cent being glass, cold-pressing to obtain a green compact of 9