2001 Volume 42 Issue 7 Pages 1219-1224
Polymer plating of triazine dithiols on magnesium alloys and applications of the plated alloys were investigated, focusing on important factors for improvement of corrosion resistance and adhesion properties of magnesium alloys. Three kinds of triazine dithiols; 6-dihexylamino-1,3,5-triazine-2,4-dithiol monosodium salts (DHN), 6-diallylamino-1,3,5-triazine-2,4-dithiols (DAN), and 6-mercapto-1,3,5-triazine-2 4-dithiol (TTN), were prepared for imparting functions such as corrosion resistance and direct adhesion to magnesium alloys. In polymer plating of DHN, film thickness initially increases with current density, reaches a maximum at 1 A/m2, and then decreases. Film thickness initially increases with DHN concentration, reaches a maximum at 8 mol/m3, and then decreases. Polymer plating of DAN yields good polymer film on magnesium in terms of adhesion when 10 mol/m3 NaOH/Na2CO3 aqueous solution is used as an electrolytic solution. An 8 mol/m3 DHN aqueous solution was found to impart the best corrosion resistance for reaction resistance and corrosion current density. In direct adhesion of EPDM to polymer-plated magnesium alloys, a film thickness of near 100 nm imparts the highest peel strength. In injection molding adhesion of PPS polymer to polymer-plated magnesium alloys, high tensile shear strength is obtained when mold temperature exceeds 140°C.