Signification et utilisation
5.1 La méthode de test a été initialement développée à des fins de recherche et développement; Cependant, dans des spécifications de matériaux spécifiques, it is referenced to evaluate production materials (see section 14 on accuracy and deviation).

5.2 Using this test method can effectively predict the spalling corrosion behavior of these alloys in various types of outdoor services, especially in Marine and industrial environments. The four-test solution is highly corrosive and represents a more stringent type of environmental service, and certainly does not include unusual chemicals that are unlikely to be encountered in the natural environment.

5.3 Exfoliation grades were chosen arbitrarily in this test to illustrate the wide range of resistance to exfoliation. Cependant, it remains to be determined whether a correlation can be established between EXCO test ratings and the actual conditions of use for a given alloy. The Aluminium Alloy Peeling Corrosion Working Group (G01.05.02.08) is conducting an activity to conduct outdoor exposure testing for this purpose. Par exemple, it has been reported that Al-Zn-Mg-Cu alloy samples rated EA or P in the 48-hour EXCO test did not experience more than a small amount of early peeling (EA) during six to nine years of exposure to the coastal atmosphere, while in most cases ED grade materials showed significant peeling within a year in the coastal atmosphere. It is expected that more comparisons will be provided as outdoor testing expands.

Méthode d'essai ASTM G34-2020 pour la corrosion cyclique par chaleur humide

Rayon
1.1 This test method covers a constant immersion exfoliation corrosion (EXCO) test procedure for high strength 2XXX and 7XXX series aluminum alloys.

Note 1: This test method was originally developed for research and development purposes; Cependant, dans des spécifications de matériaux spécifiques, it is referred to as applicable for evaluating production materials (see section 14, “Accuracy and Deviation”).

1.2 This test method is applicable to all forged products, such as sheets, plates, extrusions and forgings produced by conventional ingot metallurgy processes.

1.3 The test method can be used on any form of sample or part that can be immersed in the test solution.

1.4 Cette norme n'est pas destinée à répondre à tous les problèmes de sécurité, si seulement, associé à son utilisation. Il est de la responsabilité des utilisateurs de cette norme d'établir des mesures de sécurité appropriées., pratiques sanitaires et environnementales et pour déterminer l’applicabilité des restrictions réglementaires avant utilisation.

1.5 Cette norme internationale est basée sur les principes de normalisation internationalement reconnus établis dans la Décision sur les principes pour l'élaboration de normes internationales., Lignes directrices et recommandations émises par le Comité des obstacles techniques au commerce de l'OMC.