Pitting of aluminum alloys occurs if the electrolyte contains a low level of chloride anions, and if the alloy is at a potential above the pitting potential. Intergranular corrosion of coppercontaining aa6xxx almgsi aluminum alloys article pdf available in journal of the electrochemical society 15511. Alloys that have been extruded or otherwise worked heavily, with a microstructure of elongated, flattened grains, are particularly prone to this damage. The aa5xxxseries is a lightweight and relatively high strength family of aluminum alloys that are solid solution strengthened via a supersaturation of the al matrix with up to 5. C for varying durations of time and then mechanically tested in salt water. The alloys containing copper as a major alloying constituent over 1% are somewhat less resistant than the other aluminum base alloys, whereas the alclad alloys are generally the most resistant. Pdf intergranular corrosion of coppercontaining aa6xxx. Effects of mn, zn additions and cooling rate on mechanical. Pdf intergranular corrosion of an aluminummagnesium. Intergranular corrosion of 5xxx series aluminum alloys by mass loss after exposure to nitric acid. The corrosion attack on aluminum alloys in soil depends on the composition and climatic conditions of the soil. Pitting corrosion is very similar to crevice corrosion. Almg alloys 5xxx containing less than 3% mg, are resistant to intergranular corrosion.
Intergranular corrosion sensitivity is studied for the friction stir weld nugget of aluminum alloy 2050t8. Intergranular cracking of aluminum alloys occurs by a variety of processes in a host of structural components. Pitting initiates at defects on the surface of the aluminum, such as at second phase particles or on grain boundaries. Alloys of 7xxx series are prone to intergranular attack because of the formation of a cual. The intergranular intercrystalline corrosion igc of a heattreated aluminummagnesiumsiliconcopper alloy was investigated using scanning electron microscopy sem and transmission electron.
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