Papers by Author: Xin Sun

Abstract: Cr-α-Al₂O₃ composite coatings were prepared by direct current deposition experiments from Cr(Ⅲ) plating bath and the thickness of composite coatings could be up to 14 μm. The obtained Cr-α-Al₂O₃ coatings and Cr coatings were characterized by means of EDS, SEM and microhardness measurement. Results revealed that Cr-α-Al₂O₃ coatings exhibit fine-grained structure with uniform surface and the highest microhardness values(692 HV) when the α-Al₂O₃ content of coatings was 15g/L, although some pores and defects are still present in the coatings. Analysis of Tafel curves indicated that the presence of α-Al₂O₃ in the Cr coatings show better features in the corrosion resistance both in H₂SO₄ and NaOH solution than those prepared from the bath without α-Al₂O₃.