Abstract: As-cast and corrosive microstructures of AZ91D alloy containing various Ce contents were observed by optical microscope (OM). The phase compositions of the alloys before and after the corrosion were analyzed by X-ray diffraction (XRD). Meanwhile, the corrosion resistance of the alloys was tested b)."""" weight loss and potentiod)wamic polarization curve methods respectively.The results show that rod-like Al4Ce phase is formed in AZglD alloy containing certain Ce content and as-cast microstructures are refined. AZ91D-0.7e alloy has good grain refinement effect. The addition of Ce can reduce the corrosion rate and corrosion current density of AZ91D alloy and those of AZ91D-O.I0e alloy reach the minimum, which are 0.35mg/(cm^2·d) and 2.7611μA/cme with 75and 86reduction, respectively. The increasing volume fraction and reticular degree of fl phase can improve the corrosion resistance of the alloys.

Key words: AZ91D magnesium alloy, Ce modificatioon, microstructure