Aluminum alloys intergranular corrosion

H. Kaesche. Pitting Corrosion of Aluminum and Intergranular Corrosion of A1 Alloys, in Localized Corrosion. 1971. Williamsburg, VA NACE, Houston, TX. 

T. Ramgopal, P.I. Gouma, G.S. Frankel, Role of grain-boundary precipitates and solute-depleted zone on the intergranular corrosion of aluminum alloy 7150, Corrosion 58 (2002) 687—697. 

Tests for aluminum and its alloys consist of intergranular corrosion, stress corrosion cracking and corrosion fatigue as detailed below ... 

In aluminum alloys exposed to aqueous chloride solutions, corrosion fatigue cracks frequently originate at sites of pitting or intergranular corrosion. Initial crack propagation... 

F.H. Haynie and S.J. Ketcham, Electrochemical Behavior of Aluminum Alloys Susceptible to Intergranular Corrosion. II. Electrode... 

Austenitic stainless steels are the most significant class of corrosion-resistant alloys for which intergranular corrosion can be a major problem in their satisfactory use. The problem is most often encountered as a result of welding but also may result from stress-relief annealing or incorrect heat treatments. Intergranular corrosion also can occur in ferritic stainless steels and in nickel- and aluminum-base alloys. 

Fig. 7.90 Effect of stressing direction on the intergranular stress-corrosion crack path in susceptible high-strength aluminum alloy. Dark boundaries are representative of ones favored for cracking for indicated direction of applied stress. Source Ref 97...

Zinc alloys with addition of >0.03% aluminum are susceptible to intergranular corrosion attack [2, 39]. 

ASTM Standard G 67, Standard Test Method for Determining the Susceptibility to Intergranular Corrosion of 5XXX Series Aluminum Alloys by Mass Loss After Exposure to Nitric Acid, Annual Book of ASTM, 1999, 03.02. 

GllO-92, Standard practice for evaluating intergranular corrosion resistance of heat treatable aluminum alloys by immersion in sodium chloride + hydrogen peroxide solution. Annual Book of ASTM Standards, ASTM International, Philadelphia, Pa., 2000, p. 481, Vol. 3.02. 

Intergranular corrosion can also occur in other metals and alloys in connection with grain boundary precipitation, for example, in aluminum magnesium (AlMg) 5 alloy, nickel chromium 30 iron (NiCr30Fe), or Ti, and in methanol with traces of water and HCl. Solution annealed austenitic chromium-nickel steels can suffer intergranular corrosion from strong oxidants such as chromium... 

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