Paper Title:
Effect of Chrome-Free Chemical Conversion Coating on Corrosion Behavior of Magnesium Alloy AZ91D
  Abstract

The different chrome-free chemical conversion coatings were prepared on AZ91D magnesium alloy and SEM was used to observe the surface. The corrosion behaviors of die-casting AZ91D magnesium alloy with different coating in chloride environment were investigated by hydrogen gas evolution in immersion test, salt spray test and electrochemical measurement. The results showed that the corrosion resistance of magnesium alloy treated with two-step chemical conversion and sealing was the highest and was comparable with that of chromating, and followed by two-step chemical conversion treatment without sealing. The one-step chemical conversion treatment had the lowest corrosion resistance. Polarization and EIS characteristics in 5% NaCl solution depended on the type of surface treatment and correlated well with the order of corrosion resistance. Contrasted with one-step chemical conversion coating, the coating of two-step chemical conversion with sealing on magnesium alloy had more excellent corrosion resistance because the |Z| increased, the corrosion area was decreased and the time of the first pitting occurrence was prolonged. It is expected that this experiment can provide a foundation for designing more super chemical conversion coating to replacing the chromate conversion.

  Info
Periodical
Advanced Materials Research (Volumes 15-17)
Edited by
T. Chandra, K. Tsuzaki, M. Militzer and C. Ravindran
Pages
473-478
DOI
10.4028/www.scientific.net/AMR.15-17.473
Citation
L. Q. Bai, D. Li, B. L. Guo, M. Guo, "Effect of Chrome-Free Chemical Conversion Coating on Corrosion Behavior of Magnesium Alloy AZ91D", Advanced Materials Research, Vols. 15-17, pp. 473-478, 2007
Online since
February 2006
Export
Price
$32.00
Share

In order to see related information, you need to Login.

In order to see related information, you need to Login.

Authors: Xing Wu Qiu
Abstract:AZ91D magnesium alloy were used as the materials in this experiment. The directly electroless nickel plating, the stannate conversion...
698
Authors: Yu Yin Wang, Guo Zhong Li
Abstract:In order to improve the mechanical performance of straw fiber reinforced gypsum composite materials, corn straw fiber was modified by...
299
Authors: Amrin Astuty, Syairah Mohamad Zubir Dalila, Mohd Anuar Liza, Mohd Faim Aezal
Chapter 7: Coatings and Surface Engineering
Abstract:Mechanical fasteners such as screws, nuts, bolts, and washers are integral components in a vehicle. Rust or corrosion mechanisms of fasteners...
560
Authors: Nirada Pintuperakovit, Waleed Mohammed, Patama Visuttipitukul, Sittha Sukkasi, Yuttanant Boonyongmaneerat
Chapter 2: Materials Processing Technology
Abstract:Chromate conversion coating is an important surface finishing process for electroplated zinc coatings that are widely employed in automotive...
161