Peel tests environmental testing

The chemical cleaning methods used for aluminum will have slightly different effectiveness with different aluminum alloys. The permanence of these bonds will also depend on the type of alloys used because of their different corrosion rates under extreme environmental conditions. The yield strength of the alloy also has an influence on bond strength when stressed in shear. The peel test is usually considered a more meaningful... 

Section 1.6 1979 Recommended environmental storage conditions for adhesive joints prior to heat resistance or peeling tests. 

Nase, M., Zankel, A., Langer, B., Baumann, H.J., GreUmann, W., Poelt, R Investigation of the peel behavior of polyethylene/polybutene-1 peel films using in-situ peel tests With environmental scanning electron microscopy. Polymer 49, 5458-5466 (2008)... 

Adhesion difficulties due to surface effects and treatments can be present in initial adhesion testing such as lap shear or T-peel. However, it may also be hidden in these tests only to resurface during more demanding adhesion tests, such as hot water immersion (90-100°C) or environmental cycling. When bonding composites in combination with more traditional substrates, it is important to perform a variety of tests to verify results. 

Three main types of test methods are used to determine the physical properties of PSAs peel, tack, and shear (8) (see also Adhesion). Standard test methods are available for all three properties, and numerous additional variations of tests measuring these properties have also heen used (9). Environmental conditions are an extremely important factor in all PSA testing. PSAs are almost always very sensitive to temperature. Many PSAs are also sensitive to humidity, particularly if stored in environments where they can either ahsorh or lose moisture. 

Fig. 24. Specimen and device for testing peel strength under environmental exposure (D-2918).

A paper by Hampel proposes a specification including the peel strength, the electrical resistance of the conductor tracks, and a series of environmental tests... 

The bond between the FRP and concrete has been characterized by using a variety of experimental techniques and a number of studies have been conducted to assess the effects of defects in the substrate, FRP, and the interface as well as environmental conditions prevalent during the application of the FRP. A number of studies have also been conducted using flexural specimens or peel-type tests to assess the effect of environmental exposure on the performance of the rehabilitated beams and fracture toughness, respectively. While these provide useful information regarding the effects of environmental exposure, they do not focus on the critical region of the bond between the concrete and FRP at a level that can be directly of use to the designer or used for field assessment of durability. 

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