Atmospheric Corrosion of Mg Alloy AZ91D Fabricated by a Semi-Solid Casting Technique: The Influence of Microstructure
Journal article, 2015

The atmospheric corrosion behavior of alloy AZ91D produced by a semi-solid metal (SSM) technique and by conventional high pressure die casting (HPDC) was investigated for up to 1176 hours in the laboratory. Alloy AZ91D in the SSM state was fabricated using a rheocasting (RC) technique in which the slurry was prepared by the RheoMetal process. Exposures were performed in 95% RH air at 22 and 4 degrees C. The RC alloy AZ91D exhibited significantly better corrosion resistance than the HPDC material at two temperatures studied. The effect of casting technology on corrosion is explained in terms of the microstructural differences between the materials. For example, the larger number density of cathodic beta phase particles in the HPDC material initially causes relatively rapid corrosion compared to the RC material. During later stages of corrosion, the more network-like beta phase particles in the RC alloy act as a corrosion barrier, further improving the relative corrosion resistance of the RC material.

Author

Mohsen Esmaily

Chalmers, Chemistry and Chemical Engineering, Energy and Material, Environmental Inorganic Chemistry

Nooshin Mortazavi Seyedeh

Chalmers, Applied Physics, Materials Microstructure

Jan-Erik Svensson

Chalmers, Chemistry and Chemical Engineering, Energy and Material, Environmental Inorganic Chemistry

Mats Halvarsson

Chalmers, Applied Physics, Materials Microstructure

D. B. Blucher

SINTEF Materials and Chemistry

A. E. W. Jarfors

School of engineering Jönköping university

M. Wessen

School of engineering Jönköping university

Lars-Gunnar Johansson

Chalmers, Chemistry and Chemical Engineering, Energy and Material, Environmental Inorganic Chemistry

Journal of the Electrochemical Society

0013-4651 (ISSN)

Vol. 162 7 C311-C321

Subject Categories

Materials Chemistry

Corrosion Engineering

DOI

10.1149/2.0341507jes

More information

Latest update

5/14/2018