Preparation of Trivalent Chromium Coating on 6063 Aluminum Alloy

Abstract

Abstract. The trivalent chromium coating was deposited on the surface of 6063 aluminum alloy with Cr 2 (SO 4 ) 3 , H 3 PO 4 and K 2 ZrF 6 . The performances of trivalent chromium conversion coating were analyzed by CuSO4 dropping corrosion test, electrochemical polarization curve, scanning electron microscope (SEM) and energy dispersive X-ray analysis (EDAX). The conversion coating shows gray color and consists of Cr, Zr, K, Al, P, O. The analytical results indicate that the aluminum alloy coated with trivalent chromium exhibits better corrosion resistance than the pure aluminum alloy.