Abstract: An improved method of providing a protective coating on the surface of aluminum or aluminum alloys comprising: alkaline-cleaning the surface using a nonchromated and nonsilicated alkaline cleaner, following by a rinse in hot water; (b) deoxidizing the surface by immersion thereof in a nonchromated deoxidizer at room temperature, followed by a rinse in hot water; and (c) immersing the surface in boiling water for a period of time. Following the immersion step, the aluminum-containing part may be painted, powder-coated, or adhesive-bonded without requiring any wash primers to activate the substrate. Further, the part may be stored indefinitely in an acid-free paper that does not leave any residues. The only treatment required before painting, powder-coating, or adhesive bonding is a removal of any fingerprints in a suitable solvent such as acetone or iso-propyl alcohol.

Abstract: Surface preparation methods and materials that provide corrosion protection for aluminum and its alloys without the use of chromate and that protects aluminum surfaces against corrosion nearly as well as a chromate conversion coating. In accordance with the present methods, aluminum parts are degreased in a general purpose cleaner and rinsed in hot tap water. The parts are then cleaned using alkaline cleaner and then rinsed in cold tap water. The parts are then deoxidized using one of two alternative steps. The parts may be deoxidized using a 20-25 volume percent Smut-Go NC solution at room temperature for 15-25 minutes. The parts may alternatively be deoxidized using a solution of 10% HNO.sub.3 and 3% NaBrO.sub.4 dissolved in water at room temperature for 15-25 minutes. The deoxidized aluminum parts are then rinsed in cold tap water. The parts are then immersed in boiling deionized water and then sealed using a 1% LiNO.sub.3, 10% Al(NO.sub.3).sub.3 and 10% aluminum silicate solution.

Abstract: Bonding of polystyrene foam details together to produce lost foam molds suitable for casting metallic details is accomplished by coating one of the two mating surfaces of the parts with a phenol-formaldehyde adhesive. The two parts are joined together and the mated assembly is placed in a microwave oven. Exposure of the assembly to microwave energy for a pre-selected period of time effects the bonding.