Eiki Takeshima

Evaluation of the Service Life of Galvanized Steel Sheet Coated with Silicone Polyester Resin

This paper reports about the evaluation of the service life of a galvanized steel sheet coated with thermosetting silicone polyester resin and intended for an exterior building material. The contents are as follows:(1)A composite cycle test is the best method as an accelerated weathering test because it gives a largest acceleration rate to deterioration and reveals the similar deteriorated condition to the outdoor weathering test.(2) A complex deterioration of the resin proceeds in the film surface layer, with the thickening of remaining silicon dioxide being observed in particular.(3) Complex deterioration factors affect the properties of the material.(4) Appearance change, physical change and decrease in adhesion strength between film and steel sheet are caused by the chemical change of the film.(5) The silicone polyester resin coated galvanized steel sheet has a high abrasion and corrosion resistance.