ISSN:
1662-9752
Source:
Scientific.Net: Materials Science & Technology / Trans Tech Publications Archiv 1984-2008
Topics:
Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics
Notes:
Intergranular corrosion is a significant concern for Al-Mg alloys when subjected to acorrosive salt-water environment. To address this issue, the standard composition of a 5XXX seriesaluminum alloy (AA5083) was modified in an attempt to improve the alloy’s overall corrosionresistance through alloying and thermal processing. The concept being that through alloying and heattreatments, desirable precipitate phases such as τ- and/or τ-copper rich phase(s) that are known to offercorrosion resistance would potentially form that could effectively improve intergranular corrosionbehavior. Therefore, the chemical composition of standard AA5083 was modified by adding variousamounts of copper and zinc. Sensitization heat treatments were then performed to determine thespecific conditions under which these phases would form. LOM, SEM, STEM imaging andconventional TEM were used to analyze microstructural features. Corrosion was attributed to anetwork of detrimental Mg-rich grain boundary precipitates in the standard alloy. Alloying with Cu andZn can offer improved intergranular corrosion behavior. The mechanism seems to be either by delayingor eliminating precipitation at the grain boundaries
Type of Medium:
Electronic Resource
URL:
http://www.tib-hannover.de/fulltexts/2011/0528/02/13/transtech_doi~10.4028%252Fwww.scientific.net%252FMSF.519-521.327.pdf
