Abstract
We made experiments on the durability of various sprayed metal coatings and on the effect of several sealing materials in order to make up for the poor durability of coatings due to their porosity.
Sprayed metals and sealing materials used for this experiment were as follows:
(1) Sprayed metals:
Zinc, aluminum, copper, brass, tin, lead, and 18-8 stainless steel.
(2) Sealing materials:
Phenol resin paint, and epoxy resin paint (heat curing type)
Polyvinylchloride paint, and chlorinated rubber paint (air drying type)
As a result of the experiments zinc and aluminum were suitable for preventing steel from corrosion, while other metals had no rust-preventive effect because of their porosity of coatings.
Though zinc and aluminum were excellent in that effect, sufficient effect could not be expected from them without suitable sealing materials because of the high dissolubility of coatings.
Heat curing paints were the best sealing materials. If only complete coating was obtained, even air drying paints would form ideal rust-preventive layers with their sealing effect and the characteristics of sprayed coatings.
The coatings treated by silicate treatment, when compared with non-treated coatings, showed considerable sealing effect. The practical application of this treatment, however, will be limited, since the treated coating are essentially inferior to paint films.
