Abstract
Before enamelling, plates of aluminum alloys were treated anodic oxidation with mono and mixed aqueous solutions of sodium metasilicate, sodium perborate or lithium borate, and the adhesion of enamel was investigated measuring bending, tensile and thermal shock.
(1) Aluminum alloy plates pretreated by anodic oxidation with mono or mixed aqueous solution sodium metasilicate, sodium perborate or lithium borate showed better adhesiveness than those of treated chemically or without treatment.
(2) It was easy to get glossy and transparent enamel by anodic oxidation with mixed aqueous solution.
(3) The strength of test samples by chemical treatment and those without treatment was lower than those by anodic oxidation.
(4) The enamel on the plate chemically pretreated or no treatment showed good resistance for thermal shock.
The enamel was transparent in the case of anodic oxidation, and gray or brown in the case of chemical or no treatment. Hence, by using colored frit from the beginning, a single enamelling process would be sufficient to get proper shade.
